Submounts for semiconductor light emitting devices and methods of forming packaged light emitting devices including dispensed encapsulants

CROSS-REFERENCE TO RELATED APPLICATION

0001This application is a divisional of and claims priority to U.S. patent application Ser. No. 11/197,096, filed on Aug. 4, 2005.

FIELD OF THE INVENTION

0002This invention relates to semiconductor light emitting devices and methods of fabricating semiconductor light emitting devices, and more particularly to packaging and packaging methods for semiconductor light emitting devices.

BACKGROUND

0003Light emitting diodes and laser diodes are well known solid state electronic devices capable of generating light upon application of a sufficient voltage. Light emitting diodes and laser diodes may be generally referred to as light emitting devices (“LEDs”). Light emitting devices generally include a p-n junction formed in an epitaxial layer grown on a substrate such as sapphire, silicon, silicon carbide, gallium arsenide and the like. The wavelength distribution of the light generated by the LED generally depends on the material from which the p-n junction is fabricated and the structure of the thin epitaxial layers that make up the active region of the device.

0004Typically, an LED includes a substrate, an n-type epitaxial region formed on the substrate and a p-type epitaxial region formed on the n-type epitaxial region (or vice-versa). In order to facilitate the application of a voltage to the device, an anode ohmic contact is formed on a p-type region of the device (typically, an exposed p-type epitaxial layer) and a cathode ohmic contact is formed on an n-type region of the device (such as the substrate or an exposed n-type epitaxial layer).

0005In order to use an LED in a circuit, it is known to enclose an LED in a package to provide environmental and/or mechanical protection, color selection, focusing and the like. An LED package also includes means, such as electrical leads or traces, for electrically connecting the LED chip to an external circuit. In a typical package <b>10</b> illustrated in <figref idref="DRAWINGS">FIG. 1A</figref>, an LED <b>12</b> is mounted on a reflective cup <b>13</b> by means of a solder bond or conductive epoxy. One or more wirebonds connect the ohmic contacts of the LED <b>12</b> to leads <b>15</b>A, <b>15</b>B, which may be attached to or integral with the reflective cup <b>13</b>. The reflective cup may be filled with an encapsulant material <b>16</b> containing a wavelength conversion material such as a phosphor. Light emitted by the LED at a first wavelength may be absorbed by the phosphor, which may responsively emit light at a second wavelength. The entire assembly is then encapsulated in a clear protective resin <b>14</b>, which may be molded in the shape of a lens to collimate the light emitted from the LED chip <b>12</b>. While the reflective cup may direct light in an upward direction, optical losses may occur when the light is reflected (i.e. some light may be absorbed by the reflector cup instead of being reflected).

0006In another conventional package <b>20</b> illustrated in <figref idref="DRAWINGS">FIG. 1B</figref>, a plurality of LED chips <b>22</b> are mounted onto a printed circuit board (PCB) carrier <b>23</b>. One or more wirebond connections are made between ohmic contacts on the LEDs <b>22</b> and electrical traces <b>25</b>A, <b>25</b>B on the PCB <b>23</b>. Each mounted LED <b>22</b> is then covered with a drop of clear resin <b>24</b>, which may provide environmental and mechanical protection to the chips while also acting as a lens. The individual packaged LEDs <b>22</b> may then be separated by sawing the PCB carrier <b>23</b> into small squares, each of which contains one or more LED chips <b>22</b>.

SUMMARY

0007Embodiments of the invention provide a submount for mounting an LED including a substrate having an upper surface, a die attach pad configured to receive an LED chip on the upper surface of the substrate. A first meniscus control feature on the substrate surrounds the die attach pad defines a first encapsulant region of the upper surface of the substrate. A second meniscus control feature on the substrate surrounds the first encapsulant region and defines a second encapsulant region of the upper surface of the substrate. In some embodiments, the first and second meniscus control features are substantially coplanar with the die attach pad.

0008In other embodiments, the substrate is a printed circuit board (PCB). The die attach pad and the first and second meniscus control features may be formed as metal traces on the substrate. In some embodiments, the meniscus control features may include a material different than the die attach pad. For example, the meniscus control features may include a polymer such as a solder mask material and/or polyimide. In some embodiments, the die attach pad and the first and second meniscus control features include the same material. Further, the first and/or second meniscus control features may include a plated copper or other metal film formed directly on the substrate. The first and/or second meniscus control feature may include a corner of a patterned feature on the substrate. Further, the die attach pad may include a metal stack on the metal trace.

0009In further embodiments of the invention, a wirebond pad on the substrate is disposed within the second encapsulant region. The wirebond pad may be disposed within the first encapsulant region. The substrate may include a lower surface opposite the upper surface of the substrate, and the submount may further include an electrode on the lower surface of the substrate. A conductive via may extend through the substrate from the electrode to the die attach pad. Further, a conductive via may extend through the substrate from the electrode to the wirebond pad.

0010In other embodiments, an electrode may be on the upper surface of the substrate. The electrode may be formed of the same material as the first and second meniscus control features. Further, a conductive via may extend through the substrate from the lower electrode to the electrode on the upper surface of the substrate.

0011In yet further embodiments, the submount may also include a third meniscus control feature disposed within the first encapsulant region and surrounding the die attach pad. The third meniscus control feature may define a third encapsulant region within the first encapsulant region. The first meniscus control feature and the third meniscus control feature may together define a region in the first encapsulant region surrounding the third encapsulant region. The region of the first encapsulant region defined by the first meniscus control feature and the third meniscus control feature may be ring-shaped.

0012In other embodiments, the submount may include at least one surface feature on the substrate between the first meniscus control feature and the second meniscus control feature. The submount may include a one or more surface features on the substrate between the first meniscus control feature and the second meniscus control feature, wherein a path extending in a radial direction from the first meniscus control feature to the second meniscus control feature is interrupted by at least one surface feature. The surface feature(s) may be continuous or discontinuous and may be formed of the same material as the first and second meniscus control features. For example, the surface feature(s) may include a metal film such as a plated copper film. In some embodiments, the surface feature(s) may include a material different than the die attach pad. For example, the surface feature(s) may include a polymer such as a solder mask material and/or polyimide.

0013In yet other embodiments, a submount for mounting an LED includes a substrate having an upper surface and a conductive pattern on the upper surface of the substrate. The conductive pattern includes a portion configured to receive an LED chip. A first meniscus control feature on the substrate surrounds the submount and defines a first encapsulant region of the upper surface of the substrate. A second meniscus control feature on the substrate surrounds the first encapsulant region and defines a second encapsulant region of the upper surface of the substrate.

0014The conductive pattern may include a conductive trace directly on the substrate, and may further include a wirebond pad disposed within the second encapsulant region. The wirebond pad may be disposed within the first encapsulant region. The conductive pattern may additionally include an electrode disposed outside the second encapsulant region.

0015In some embodiments, a packaged LED includes a submount as described above and further includes an LED chip on the die attach pad, a first encapsulant on the substrate within the first encapsulant region, and a second encapsulant on the substrate within the second encapsulant region and covering the first encapsulant.

0016A packaged LED according to some embodiments of the invention may further include a wirebond connection between the LED chip and the wirebond pad. In addition, a packaged LED may further include an electrostatic discharge (ESD) protection chip on the die attach pad. The first and/or second encapsulant may include a silicone gel and/or an epoxy resin. In addition, the first and/or encapsulant may include a wavelength conversion material such as, for example, a phosphor and/or a nanocrystal.

0017In some embodiments a packaged LED includes a submount as described above, and further includes an LED chip on the die attach pad. A first encapsulant is provided on the substrate within the region of the first encapsulant region defined by the first meniscus control feature and the second meniscus control feature. A second encapsulant is provided on the substrate within the third encapsulant region. A third encapsulant is provided on the substrate within the second encapsulant region covering the first encapsulant and the second encapsulant.

0018In yet other embodiments, methods of forming LED submounts and packaged LEDs are provided including depositing a metal layer on a substrate and patterning the metal layer to form a die attach pad, a first meniscus control feature that surrounds the die attach pad and defines a first encapsulant region of the upper surface of the substrate, and a second meniscus control feature that surrounds the first encapsulant region and defines a second encapsulant region of the upper surface of the substrate.

0019Some methods of forming a packaged LED include depositing a metal layer on a substrate and patterning the metal layer to form a die attach pad, a first meniscus control feature, and a second meniscus control feature. The first meniscus control feature may surround the die attach pad and define a first encapsulant region of the upper surface of the substrate. The second meniscus control feature may surround the first encapsulant region and define a second encapsulant region of the upper surface of the substrate.

0020Other methods according to the invention further include mounting an LED chip on the die attach pad on the substrate. A first encapsulant material may be dispensed onto the substrate and the mounted LED chip within the first encapsulant region, and the first encapsulant material may be cured. After curing the first encapsulant material, a second encapsulant material may be dispensed onto the substrate within the second encapsulant region, and the second encapsulant material may be cured. A quantity of encapsulant material may be pre-dispensed adjacent the LED chip prior to dispensing the first encapsulant material. In some embodiments, a sufficient quantity of the first encapsulant material may be dispensed to substantially cover the LED chip.

0021In some embodiments, patterning the metal layer includes patterning the metal layer to form a wirebond pad within the second encapsulant region. The method may further include forming a wirebond connection between the LED chip and the wirebond pad.

0022In some embodiments, the first encapsulant material includes a wavelength conversion material, such as a phosphor and/or a nanocrystal. Patterning the metal layer may further include forming at least one surface feature between the first and second meniscus control features. The surface features may help the encapsulant material adhere to the surface of the substrate and/or cling to the meniscus control features.

0023Methods of forming a packaged LED according to further embodiments of the invention include depositing a metal layer on a substrate and patterning the metal layer to form a die attach pad, a first meniscus control feature, a second meniscus control feature and a third meniscus control feature. The first meniscus control feature may surround the die attach pad and define a first encapsulant region of the upper surface of the substrate. The second meniscus control feature may surround the first encapsulant region and define a second encapsulant region of the upper surface of the substrate. The third meniscus control feature may be formed within the first encapsulant region and may surround the die attach pad to thereby define a third encapsulant region within the first encapsulant region. The first meniscus control feature and the third meniscus control feature may together define a region in the first encapsulant region surrounding the third encapsulant region. The first encapsulant material may be dispensed in a shape corresponding to a shape of the region surrounding the third encapsulant region. For example, in some embodiments of the invention, the shape of the region surrounding the third encapsulant region is annular, and the first encapsulant material may be dispensed by moving a dispensing needle in a circular motion.

0024In other embodiments, an LED chip is mounted on the die attach pad and a first encapsulant material is dispensed within the region in the first encapsulant region defined by the first meniscus control feature and the third meniscus control feature. The first encapsulant material may then be cured and a second encapsulant material may be dispensed onto the substrate within the third encapsulant region. The second encapsulant material may then be cured. A third encapsulant material may be dispensed within the second encapsulant region, and the third encapsulant material may be cured. The dispensed first encapsulant material may define a cavity around the LED chip, and dispensing the second encapsulant material may include dispensing the second encapsulant material into the cavity around the LED chip after curing the first encapsulant material. The first encapsulant material, the second encapsulant material and/or the third encapsulant material may include a wavelength conversion material.

0025In further methods, a meniscus extension feature may be formed outside the second encapsulant region. The meniscus extension feature may surround the second encapsulant region and define a encapsulant extension area of the upper surface of the substrate. A fourth encapsulant material may be dispensed in the encapsulant extension area after curing the second encapsulant material and curing the fourth encapsulant material. The encapsulant extension area may have a peripheral shape that is different from a peripheral shape of the second encapsulant region. For example, the encapsulant extension area may have a peripheral shape that is oval, circular, rectangular and/or generally square. In some embodiments, the meniscus extension features may include a material different than the die attach pad. For example, the meniscus control features may include a polymer such as a solder mask material and/or polyimide.

BRIEF DESCRIPTION OF THE DRAWINGS

0026<figref idref="DRAWINGS">FIGS. 1A and 1B</figref> are cross-sectional side views illustrating conventional light emitting device packages;

0027<figref idref="DRAWINGS">FIG. 2A</figref> is a cross-sectional view illustrating a light emitting device submount according to some embodiments of the invention;

0028<figref idref="DRAWINGS">FIG. 2B</figref> is a top view illustrating the light emitting device submount of <figref idref="DRAWINGS">FIG. 2A</figref>;

0029<figref idref="DRAWINGS">FIG. 2C</figref> is a cross sectional view illustrating a light emitting device package according to some embodiments of the invention utilizing the submount of <figref idref="DRAWINGS">FIG. 2A</figref>;

0030<figref idref="DRAWINGS">FIG. 3A</figref> is a cross-sectional view illustrating a light emitting device submount according to further embodiments of the invention;

0031<figref idref="DRAWINGS">FIG. 3B</figref> is a top view illustrating the light emitting device submount of <figref idref="DRAWINGS">FIG. 3A</figref>;

0032<figref idref="DRAWINGS">FIG. 3C</figref> is a cross sectional view illustrating methods of forming a light emitting device package according to some embodiments of the invention utilizing the submount of <figref idref="DRAWINGS">FIG. 3A</figref>;

0033<figref idref="DRAWINGS">FIG. 3D</figref> is a cross sectional view illustrating a light emitting device package according to some embodiments of the invention utilizing the submount of <figref idref="DRAWINGS">FIG. 3A</figref>;

0034<figref idref="DRAWINGS">FIGS. 4A-4C</figref> are cross sectional views illustrating methods of forming a light emitting device package according to some embodiments of the invention;

0035<figref idref="DRAWINGS">FIG. 5</figref> is a top view illustrating a light emitting device submount according to further embodiments of the invention;

0036<figref idref="DRAWINGS">FIG. 6A</figref> is a top view illustrating a light emitting device submount according to further embodiments of the invention;

0037<figref idref="DRAWINGS">FIG. 6B</figref> is a cross sectional view illustrating a light emitting device package according to some embodiments of the invention utilizing the submount of <figref idref="DRAWINGS">FIG. 6A</figref>;

0038<figref idref="DRAWINGS">FIG. 6C</figref> is a perspective view of a light emitting device package according to some embodiments of the invention utilizing the submount of <figref idref="DRAWINGS">FIG. 6A</figref>;

0039<figref idref="DRAWINGS">FIG. 7</figref> is a top view illustrating a light emitting device submount according to further embodiments of the invention;

0040<figref idref="DRAWINGS">FIG. 8</figref> is a schematic illustration of a system for dispensing an encapsulant material for use in packaging a light emitting device according to some embodiments of the invention; and

0041<figref idref="DRAWINGS">FIGS. 9-11</figref> are flowcharts illustrating methods according to some embodiments of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

0042The present invention now will be described more fully with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout.

0043It will be understood that when an element such as a layer, region or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. It will be understood that if part of an element, such as a surface, is referred to as “inner,” it is farther from the outside of the device than other parts of the element. Furthermore, relative terms such as “beneath” or “overlies” may be used herein to describe a relationship of one layer or region to another layer or region relative to a substrate or base layer as illustrated in the figures. It will be understood that these terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures. Finally, the term “directly” means that there are no intervening elements. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, the common abbreviation “e.g.”, which derives from the Latin phrase “exempli gratia,” may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. If used herein, the common abbreviation “i.e.”, which derives from the Latin phrase “id est,” may be used to specify a particular item from a more general recitation.

0044It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

0045Embodiments of the invention are described herein with reference to cross-sectional, perspective, and/or plan view illustrations that are schematic illustrations of idealized embodiments of the invention. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments of the invention should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as a rectangle will, typically, have rounded or curved features due to normal manufacturing tolerances. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region of a device and are not intended to limit the scope of the invention.

0046Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and this specification and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

0047Various embodiments of the present invention for packaging a semiconductor light emitting device will be described herein. As used herein, the term semiconductor light emitting device may include a light emitting diode, laser diode and/or other semiconductor device which includes one or more semiconductor layers, which may include silicon, silicon carbide, gallium nitride and/or other semiconductor materials, a substrate which may include sapphire, silicon, silicon carbide and/or other microelectronic substrates, and one or more contact layers which may include metal and/or other conductive layers. In some embodiments, ultraviolet, blue and/or green light emitting diodes may be provided. Red and/or amber LEDs may also be provided. The design and fabrication of semiconductor light emitting devices are well known to those having skill in the art and need not be described in detail herein.

0048For example, the semiconductor light emitting device may be gallium nitride-based LEDs or lasers fabricated on a silicon carbide substrate such as those devices manufactured and sold by Cree, Inc. of Durham, N.C. The present invention may be suitable for use with LEDs and/or lasers as described in U.S. Pat. Nos. 6,201,262; 6,187,606; 6,120,600; 5,912,477; 5,739,554; 5,631,190; 5,604,135; 5,523,589; 5,416,342; 5,393,993; 5,338,944; 5,210,051; 5,027,168; 5,027,168; 4,966,862 and/or 4,918,497, the disclosures of which are incorporated herein by reference as if set forth fully herein. Other suitable LEDs and/or lasers are described in published U.S. Patent Publication No. US 2003/0006418 A1 entitled Group III Nitride Based Light Emitting Diode Structures With a Quantum Well and Superlattice, Group III Nitride Based Quantum Well Structures and Group III Nitride Based Superlattice Structures, published Jan. 9, 2003, as well as published U.S. Patent Publication No. US 2002/0123164 A1 entitled Light Emitting Diodes Including Modifications for Light Extraction and Manufacturing Methods Therefor. Furthermore, phosphor coated LEDs, such as those described in U.S. Patent Publication No. 2004/0056260 A1, entitled Phosphor-Coated Light Emitting Diodes Including Tapered Sidewalls and Fabrication Methods Therefor, the disclosure of which is incorporated by reference herein as if set forth fully, may also be suitable for use in embodiments of the present invention. The LEDs and/or lasers may be configured to operate such that light emission occurs through the substrate. In such embodiments, the substrate may be patterned so as to enhance light output of the devices as is described, for example, in the above-cited U.S. Patent Publication No. US 2002/0123164 A1.

0049Referring to the embodiments of <figref idref="DRAWINGS">FIGS. 2A-2C</figref>, a submount <b>100</b> for mounting an LED chip <b>114</b> is illustrated. A submount <b>100</b> includes a substrate <b>110</b> having an upper surface <b>110</b>A and a lower surface <b>110</b>B. The substrate <b>110</b> may include a printed circuit board (PCB), an aluminum block, an alumina, aluminum nitride or silicon wafer, or any other suitable substrate material, such as T-Clad thermal clad insulated substrate material, available from The Bergquist Company of Chanhassen, Minn.

0050As illustrated in <figref idref="DRAWINGS">FIGS. 2A-2C</figref>, a plurality of patterned metal features are formed on the upper surface <b>110</b>A of the substrate <b>110</b>. The patterned metal features may include, for example, a die attach pad <b>112</b>, a wire bond pad <b>120</b>, a first meniscus control feature <b>116</b>, a second meniscus control feature <b>118</b>, and/or electrodes <b>124</b>. The conductive features on the top surface <b>110</b>A of substrate <b>110</b> may be formed, for example, using a plating process. A plating process may be used to plate a thin or thick metallic film on a substrate. In a typical plating process, a titanium adhesion layer and a copper seed are sequentially sputtered onto a substrate. Then, approximately 75 microns of copper are plated onto the copper seed. Thus, a plating process may be utilized to form a metal film having a characteristic stricture. A deposited metal film may be patterned using standard lithographic processes to produce metal films on the substrate having desired patterns. Alternatively, the adhesion layer and seed may be sputtered using, for example, a metal mask to form a desired pattern. A plating process may also be used to form conductive metal vias through a substrate.

0051In some embodiments of the invention, the first and second meniscus control features <b>116</b>, <b>118</b> may be formed of a material different from the die attach pad <b>112</b> and/or the wirebond pad <b>120</b>. For example, the meniscus control features <b>116</b>, <b>118</b>, <b>210</b> may comprise a polymer such as a solder mask material including for example polyimide. In particular, a polymer such as polyimide may provide a suitable material for use as a meniscus control feature since polyimide may have a high surface energy, which may provide better meniscus control properties.

0052The conductive vias may provide electrical contact between features formed on opposite sides of a substrate. Accordingly, respective conductive features formed on the upper surface of substrate <b>110</b> may be formed of the same material. For example, the conductive features may include copper deposited using a plating process. However, in some embodiments, some features may include additional metals. For example, the die attach pad <b>112</b> may be plated and/or coated with additional metals and/or other materials to make the die attach pad <b>112</b> more suitable for mounting an LED chip <b>114</b>. For example, the die attach pad <b>112</b> may be plated with additional layers such as, for example, additional adhesive, bonding, reflector and/or barrier layers (not shown).

0053As illustrated in the embodiments of <figref idref="DRAWINGS">FIG. 2B</figref>, the die attach pad <b>112</b> may be generally centrally located on the upper surface <b>110</b>A of the substrate <b>110</b>. The die attach pad <b>112</b> may be generally circular in shape, or may have any other desired shape. As further shown in <figref idref="DRAWINGS">FIG. 2B</figref>, the first meniscus control feature <b>116</b> formed on the substrate <b>110</b> surrounds the die attach pad <b>112</b> and defines a first encapsulant region <b>115</b> on the upper surface <b>110</b>A of the substrate <b>110</b> within the periphery of the first meniscus control feature <b>116</b>. The second meniscus control feature <b>118</b> surrounds the first encapsulant region <b>115</b> and defines a second encapsulant region <b>125</b> on the upper surface <b>110</b>A of the substrate <b>110</b> within the periphery of the second meniscus control feature <b>118</b>. As illustrated in <figref idref="DRAWINGS">FIG. 2B</figref>, the second encapsulant region <b>125</b> may enclose and encompass the first encapsulant region <b>115</b>.

0054The wirebond pad <b>120</b> may be formed on the upper surface <b>1110</b>A of substrate <b>110</b> within the first encapsulant region <b>115</b> and/or within the second encapsulant region <b>125</b>. One or more of the electrodes <b>124</b> may also be formed on the upper surface <b>110</b>A of the substrate <b>110</b>. In addition, one or more lower electrodes <b>126</b> may be formed on a lower surface <b>110</b>B of the substrate <b>110</b> as shown in <figref idref="DRAWINGS">FIG. 2A</figref>.

0055One or more conductive vias <b>122</b> may connect one or more of the lower electrodes <b>126</b>A, <b>126</b>B to various features on the upper surface <b>110</b>A of the substrate <b>110</b>. For example, one of the conductive vias <b>122</b> may electrically connect the electrodes <b>124</b>A, <b>124</b>B with respective lower electrodes <b>126</b>A, <b>126</b>B. Likewise, one of the conductive vias <b>122</b> may electrically connect the wire bond pad <b>120</b> with the lower electrode <b>126</b>A, and/or one of the conductive vias <b>122</b> may electrically connect the die attach pad <b>112</b> with the lower electrode <b>126</b>B.

0056As illustrated in the embodiments of <figref idref="DRAWINGS">FIG. 2C</figref>, an LED chip <b>114</b> mounted on the die attach pad <b>112</b> may be covered with an encapsulant material <b>130</b>. The encapsulant material <b>130</b> may be dispensed onto the upper surface <b>110</b>A of the substrate <b>110</b> using, for example, an automated dispense system, as described more fully below. The encapsulant material <b>130</b> may include a liquid silicone, an epoxy resin, and/or another suitable optical encapsulant material. The encapsulant material <b>130</b> may include a wavelength conversion material, such as a phosphor and/or a nanocrystal, therein to convert a wavelength of light emitted by the LED chip <b>114</b> to a second wavelength.

0057As illustrated in <figref idref="DRAWINGS">FIG. 2C</figref>, the first encapsulant material <b>130</b> is dispensed within the first encapsulant region <b>115</b> defined by the first meniscus control feature <b>116</b>. When the first encapsulant material <b>130</b> is dispensed within the first encapsulant region <b>115</b>, it may form a liquid meniscus (i.e. a curved bubble or dome) over the LED chip <b>114</b>. Surface tension in the liquid encapsulant material <b>130</b> may cause it to cling to the first meniscus control feature <b>116</b>. For example, the liquid encapsulant material <b>130</b> may cling to a corner <b>116</b><i>a </i>of the first meniscus control feature <b>116</b> and/or a surface of the first meniscus control feature <b>116</b>. For example, as illustrated in <figref idref="DRAWINGS">FIG. 2C</figref>, the encapsulant material <b>130</b> may cling to a corner <b>116</b><i>a </i>of the meniscus control feature <b>116</b> that is farthest from the center of the dome of the encapsulant material <b>130</b>. The dispensed first encapsulant material <b>130</b> may be cured, for example, by heating at an appropriate temperature for an appropriate time, to cause the first encapsulant material to harden over the LED chip <b>114</b>. It will be appreciated that a cure step may include a full and/or partial curing of an encapsulant material. A full cure may cause the liquid encapsulant material to harden completely, while a partial cure may cause the liquid encapsulant to only partially harden. For example, it may be desirable to partially cure a dispensed liquid encapsulant sufficient to permit a subsequent dispense and/or other process steps to be performed. A full cure may be performed after some or all subsequent dispenses have been performed. Alternatively, it may be desirable to perform a full cure after each dispense step.

0058As further illustrated in <figref idref="DRAWINGS">FIG. 2C</figref>, a wirebond connection <b>128</b> may be formed between the LED chip <b>114</b> and the wire bond pad <b>120</b>. The wirebond connection <b>128</b> may be made before dispense of the first encapsulant material <b>130</b>, so that when it is cured, the first encapsulant material <b>130</b> may harden around the wirebond connection <b>128</b>.

0059After the first encapsulant material <b>130</b> has been cured, a second encapsulant material <b>140</b> may be dispensed within the second encapsulant region <b>125</b> of the upper surface <b>110</b>A of the substrate <b>110</b>, i.e. over the cured first encapsulant material <b>130</b>. The second encapsulant material <b>140</b> may form a meniscus dome over the second encapsulant region <b>125</b>. As with the first encapsulant material <b>130</b>, the second encapsulant material <b>140</b> may cling to a corner <b>118</b><i>a </i>or a surface of the second meniscus control feature <b>118</b> due, for example, to surface tension in the encapsulant material <b>140</b>. The second encapsulant material <b>140</b> may include a clear silicone gel, an epoxy resin, and/or any other optically clear encapsulant material. The dispensed second encapsulant material <b>140</b> may be cured, for example, by heating the encapsulant material to a suitable temperature for a suitable time period, to cause the second encapsulant material <b>140</b> to harden. The second encapsulant material <b>140</b> may accordingly form an optically transparent lens over the cured first encapsulant material <b>130</b> and the LED chip <b>114</b>.

0060An LED chip <b>114</b> packaged in accordance with some embodiments of the invention may approximate an ideal point source of light. Thus, the design of secondary optics (not shown) for the packaged LED may be simplified. In addition, light output of the packaged LED may be improved as optical losses associated with mounting an LED chip inside a reflector cup may be avoided when an LED chip <b>114</b> is packaged in accordance with some embodiments of the invention.

0061Referring to <figref idref="DRAWINGS">FIGS. 3A-3D</figref>, further embodiments according to the invention are illustrated. As illustrated in <figref idref="DRAWINGS">FIG. 3A</figref>, a submount <b>200</b> for mounting an LED chip <b>114</b> includes a substrate <b>110</b> having an upper surface <b>110</b>A and a lower surface <b>110</b>B. A plurality of metal features are formed on the upper surface <b>110</b>A of the substrate <b>110</b>, for example, by a plating process. For example, as with the embodiment illustrated in <figref idref="DRAWINGS">FIGS. 2A-2C</figref>, the submount <b>200</b> may include a die attach pad <b>112</b>, a wire bond pad <b>120</b>, a first meniscus control feature <b>116</b> defining a first encapsulant region <b>115</b>, and a second meniscus control feature <b>118</b> defining a second encapsulant region <b>125</b>. In addition, embodiments of the invention may further include a third meniscus control feature <b>210</b> formed within the first encapsulant region <b>115</b> surrounding the die attach pad <b>112</b> and defining a third encapsulant region <b>215</b>. In addition, the first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b> define a region <b>225</b> within the first encapsulant region <b>115</b> surrounding the third encapsulant region <b>215</b>. As noted above, the meniscus control features <b>116</b>, <b>118</b>, <b>210</b> may include a material different from the die attach pad <b>112</b> and the wirebond pad <b>120</b>. For example, the meniscus control features <b>116</b>, <b>118</b>, <b>210</b> may include a polymer such as polyimide.

0062As illustrated in <figref idref="DRAWINGS">FIG. 3B</figref>, the first meniscus control feature <b>116</b>, second meniscus control feature <b>118</b> and third meniscus control feature <b>210</b> may be generally circular in shape. Accordingly, the region <b>225</b> defined between the first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b> may be generally annular or ring-shaped. An encapsulant material may be deposited in an annular region <b>225</b> in for example, a circular pattern, by moving a dispensing needle in a circular motion as discussed in more detail below. In this manner, the desired pattern may be “drawn” onto the substrate with the needle.

0063Other shapes may be possible for the first, second and third meniscus control features <b>116</b>, <b>118</b>, <b>210</b>. For example, the meniscus control features could be generally oval and/or rectangular in shape. In some embodiments, the meniscus control features may be continuous features formed on the upper surface <b>110</b>A of the substrate <b>110</b>. If the meniscus control features are not continuous features, encapsulant material dispensed within regions defined by the meniscus control features may be more likely to fail to be confined within a desired region.

0064As illustrated in <figref idref="DRAWINGS">FIG. 3A</figref>, a first encapsulant material <b>230</b> may be dispensed within the region <b>225</b> defined by the first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b>. As illustrated in <figref idref="DRAWINGS">FIG. 3A</figref>, the first encapsulant material <b>230</b> may cling to a corner <b>116</b><i>a </i>of the first meniscus control feature <b>116</b> and a corner <b>210</b><i>a </i>of the third meniscus control feature <b>210</b> that are distant from the center of region <b>225</b>. That is, when it is dispensed, the encapsulant material <b>230</b> may flow outward until it reaches an outer corner of the respective first and third meniscus control features <b>116</b>, <b>210</b> where it may be held in place, for example, by surface tension. The dispensed first encapsulant material <b>230</b> may be cured, for example, by heating the encapsulant material for a suitable period of time at a suitable temperature, by allowing the dispensed encapsulant to sit for a suitable period of time at room temperature, by exposure to UV light, and/or with the aid of a catalyst. The cured first encapsulant material <b>230</b> may thereby form a hardened ring surrounding the third encapsulant region <b>215</b> including the die attach pad <b>112</b> and the LED chip <b>114</b> mounted thereon. In some embodiments, the first encapsulant material <b>230</b> may define a cavity <b>220</b> surrounding the LED chip <b>114</b>. The height of the first encapsulant material <b>230</b> may be greater than, equal to, or less than the height of the mounted LED chip <b>114</b> on the die attach pad <b>112</b>.

0065As illustrated in <figref idref="DRAWINGS">FIG. 3C</figref>, a second encapsulant material <b>240</b> may be dispensed into the cavity <b>220</b> defined by the first encapsulant material <b>230</b>. In some embodiments, the second encapsulant material <b>240</b> may include a wavelength conversion material, such as a phosphor and/or nanocrystal. The dispensed second encapsulant material <b>240</b> may be cured in the manner described above. Next, as illustrated in <figref idref="DRAWINGS">FIG. 3D</figref>, a third encapsulant material <b>250</b> may be dispensed within the second encapsulant region <b>125</b> (i.e. over the first encapsulant material <b>230</b> and the second encapsulant material <b>240</b>). The third encapsulant material <b>250</b> may form a domed meniscus lens above the LED chip <b>114</b>, the first encapsulant material <b>230</b> and the second encapsulant material <b>240</b>. The dispensed third encapsulant material <b>250</b> may be cured as described above.

0066Further embodiments of the invention are illustrated in <figref idref="DRAWINGS">FIGS. 4A-4C</figref>. In the embodiments of <figref idref="DRAWINGS">FIGS. 4A-4C</figref>, a single patterned surface feature <b>308</b> provides the first meniscus control feature <b>116</b> at a first corner <b>308</b><i>a </i>of the feature <b>308</b> and the third meniscus control feature <b>210</b> at the opposite corner <b>308</b><i>b </i>of the feature <b>308</b>. The first corner of the feature <b>308</b> may correspond to an outer circumference of a generally ring shaped feature. The second corner of the feature <b>308</b> may correspond to an inner circumference of the feature <b>308</b>. The first encapsulant material <b>230</b> may be dispensed by dispensing an encapsulant material above the feature <b>308</b>. The encapsulant material <b>230</b> may flow outward on the feature <b>308</b> and cling to the inner and outer peripheral edges of the feature <b>308</b> (i.e., the first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b>, respectively). As shown in <figref idref="DRAWINGS">FIG. 4B</figref>, the second encapsulant material <b>240</b> may be dispensed within the cavity <b>220</b> defined by first encapsulant material <b>230</b>. The third encapsulant material <b>250</b> may be dispensed within the second encapsulant region <b>125</b> to form a dome-shaped meniscus lens above the LED chip <b>114</b>.

0067As illustrated in <figref idref="DRAWINGS">FIG. 5</figref>, some embodiments according to the invention may include one or more surface features <b>310</b> formed on the upper surface <b>110</b>A of substrate <b>110</b> between the first meniscus control feature <b>116</b> and the second meniscus control feature <b>118</b>. The surface features <b>310</b> may include a plurality of patterned features arranged to overlap one another such that an arbitrary path <b>325</b> extending in a radial direction from the first meniscus control feature <b>116</b> to the second meniscus control feature <b>118</b> is interrupted by at least one surface feature <b>310</b>. The surface features <b>310</b> may perform a number of functions. First, the surface features <b>310</b> may provide a patterned feature on the upper surface <b>110</b>A of the substrate <b>110</b> to which an encapsulant material dispensed over the surface may grip, which may provide a better, more mechanically robust connection between the encapsulant material and the upper surface <b>110</b>A of the substrate <b>110</b>. In addition, the surface features <b>310</b> may slow the flow of liquid encapsulant material across the surface of the region in which the surface features <b>310</b> are formed so that, for example, the liquid encapsulant material may be more likely to cling to a meniscus control feature as desired. For example, when an encapsulant material is dispensed within the second encapsulant region <b>125</b>, if the material flows too quickly within region <b>125</b>, it may flow over the meniscus control feature <b>118</b> and out of the second encapsulant region <b>125</b>. However, when the flow of the second encapsulant material <b>140</b> is limited by the surface features <b>310</b>, the encapsulant material may more reliably cling to the second meniscus control feature <b>118</b>. The surface features <b>310</b> are illustrated between the first meniscus control feature <b>116</b> and the second meniscus control feature <b>118</b> in <figref idref="DRAWINGS">FIG. 5</figref>. However, it will be understood by those skilled in the art that the surface features <b>310</b> could be formed in any region of the upper surface <b>110</b>A on which encapsulant material is to be dispensed Moreover, it will be understood that while the surface features <b>310</b> are illustrated as being discontinuous, the surface features <b>310</b> could be continuous provided they are small enough or formed with an appropriate shape and/or thickness such that encapsulant material will not undesirably cling to an edge or surface of the surface feature <b>310</b>.

0068Referring now to <figref idref="DRAWINGS">FIGS. 6A-6C</figref>, further embodiments according to the invention are illustrated. As shown in <figref idref="DRAWINGS">FIG. 6A</figref>, one or more meniscus extension features <b>300</b>A, <b>300</b>B may be formed on the upper surface <b>110</b>A of substrate <b>110</b> outside the second meniscus control feature <b>118</b>. As illustrated in <figref idref="DRAWINGS">FIG. 6A</figref>, the meniscus extension features <b>300</b>A, <b>300</b>B may have peripheral geometries different from the peripheral geometry of the second meniscus control feature <b>118</b>. In the embodiment illustrated in <figref idref="DRAWINGS">FIG. 6A</figref>, the second meniscus control feature <b>118</b> has a generally circular shape, while the meniscus extension features <b>300</b>A, <b>300</b>B have generally elliptical shapes with sequentially increasing axis lengths and eccentricities (i.e. increasing ratios of major axis length to minor axis length). After deposition and curing of the second encapsulant material <b>140</b>, the shape of the lens formed by the second encapsulant material <b>140</b> may be modified by dispensing additional encapsulant material within the regions defined by the encapsulant extension features <b>300</b>A and <b>300</b>B. Thus, the ultimate shape of the lens covering the LED chip <b>114</b> may be determined by the shape of the encapsulant extension features <b>300</b>A, <b>300</b>B, as well as the number of dispense/cure steps employed. Multiple encapsulant extension features <b>300</b>A, <b>300</b>B may be employed to gradually increase the size and/or change the shape of the lens while limiting the amount of encapsulant material that needs to be dispensed in any given dispense/cure cycle. Although two encapsulant extension features <b>300</b>A, <b>300</b>B are illustrated in <figref idref="DRAWINGS">FIGS. 6A-6C</figref>, it will be appreciated that more or less encapsulant extension features may be provided. The surface features <b>310</b> and/or the meniscus extension features <b>300</b>A, <b>300</b>B may include patterned metal films that may be formed concurrently with the formation of the die attach pad <b>112</b>. In some embodiments of the invention, the surface features <b>310</b> and/or the meniscus extension features <b>300</b>A, <b>300</b>B may include a different material such as a polymer such as polyimide.

0069As illustrated in <figref idref="DRAWINGS">FIG. 6B</figref>, after deposition and curing of the second encapsulant material <b>140</b>, a quantity of encapsulant material <b>330</b>A may be dispensed within the region <b>315</b>A bounded by the encapsulant extension feature <b>300</b>A. The encapsulant material <b>330</b>A may be cured to form a hardened dome <b>332</b>A having a different peripheral shape than the dome formed by the second encapsulant material <b>140</b>. If desired, a second quantity of the encapsulant material <b>330</b>B may be dispensed within the region <b>315</b>B defined by the encapsulant extension feature <b>300</b>B. The dispensed encapsulant material <b>330</b>B may be cured to form a hardened lens <b>332</b>B over the LED chip <b>114</b> having a different peripheral shape than second encapsulant material <b>140</b> or the dome <b>332</b>A. This process may be repeated as desired until a desired shape of meniscus lens is formed above the LED chip <b>114</b>.

0070<figref idref="DRAWINGS">FIG. 6C</figref> is a perspective view of a resulting LED package <b>350</b>, including a substrate <b>110</b> on which is formed a hardened dome lens <b>332</b>A.

0071As shown in <figref idref="DRAWINGS">FIG. 7</figref>, the encapsulant extension regions may have shapes other than circular or oval. In particular, the encapsulant extension features <b>300</b>A, <b>300</b>B may have peripheral shapes that are generally square and/or rectangular. Other shapes are possible and may be used to produce different shaped lenses as desired.

0072The ability to deliver small volumes of fluids accurately may be important in the manufacture of packaged LEDs according to the invention. A variety of different fabrication operations in the semiconductor industry utilize sub-microliter control of fluid dispensing. Such uses may utilize accurate, repeatable and rapid dispensing of precise amounts of fluids. Inaccurate dispensing may adversely impact the yield of a fabrication process.

0073As discussed above, after the light-emitting device <b>114</b> is mounted on the substrate <b>110</b>, a microliter quantity of an encapsulant material, such as liquid silicone gel, is dispensed into one or more encapsulant regions. In dispensing the encapsulant material, a bead of the material is typically formed on a dispensing needle and then contacted to surfaces of the substrate <b>110</b> and/or the light-emitting device <b>114</b>. When the needle is withdrawn, the surface tension between the encapsulant material and surfaces on the substrate <b>110</b> and gravity may cause the encapsulant material to tear-off from the dispensing needle and remain on the substrate <b>110</b>. In some embodiments, the encapsulant material may be dispensed in a desired pattern, for example, a circular pattern, by moving the needle in a circular motion after contacting the bead to the surface of the substrate. In this manner, the desired pattern may be “drawn” onto the substrate with the needle.

0074A system <b>400</b> for dispensing an encapsulant material for use in packaging a light emitting device according to some embodiments of the invention is illustrated in <figref idref="DRAWINGS">FIG. 8</figref>. The system <b>400</b> includes a frame <b>402</b>, which may be attached to an articulated arm (not shown) configured to controllably move the frame <b>402</b> in the X, Y, and Z dimensions. A needle mount member <b>404</b> is mounted on the frame <b>402</b>, and an encapsulant supply line <b>406</b> is coupled to the needle mount member <b>404</b> for supplying a quantity of encapsulant material to a hollow dispensing needle <b>408</b> mounted on the needle mount member <b>404</b>. A bead of encapsulant <b>410</b> may be formed at the tip of the dispensing needle <b>408</b>. As discussed above, the bead of encapsulant <b>410</b> may be dispensed onto the substrate <b>110</b> and/or the LED chip <b>114</b> by contacting the bead <b>410</b> to a surface of the substrate <b>110</b> and/or the LED chip <b>114</b>. Moreover, the shape of the dispensed encapsulant may be controlled by moving the frame <b>402</b> in the X and Y dimensions as the encapsulant is being dispensed. For example, the encapsulant may be effectively dispensed into an annular region by moving the frame in a circular pattern after contacting the bead <b>410</b> to a surface of the substrate <b>110</b> within the annular region.

0075The viscosity and/or other properties of the material used for a dispense may be selected such that, for example, wetting occurs without bubble formation. In further embodiments of the present invention, coatings may be applied to surfaces contacted by the dispensed material to speed/retard the wetting rate. For example, using certain known cleaning procedures that leave microscopic residue, selected surfaces may be treated and, thus, used to engineer the dynamics of the wetting action.

0076Due to the surface properties of the substrate <b>110</b>, the LED chip <b>114</b> and of the encapsulant material <b>410</b>, the dispensed encapsulant material may flow in a manner that could cause bubbles to form therein. In particular, the encapsulant material may move or “wick” more rapidly around the sidewalls of the LED chip <b>114</b> faster than over the top of the LED chip <b>114</b>. As a result, a bubble could be trapped on a side of the LED <b>114</b> opposite from the side where the encapsulant material is dispensed when the side-flowing encapsulant material meets, and then encapsulant material flows over the top of the LED chip <b>114</b>. Accordingly, when encapsulant material is dispensed into an encapsulant region including the LED chip <b>114</b>, such as, for example, the encapsulant region <b>115</b> illustrated in <figref idref="DRAWINGS">FIG. 2B</figref>, the encapsulant may be pre-dispensed in a first dispense portion adjacent the LED chip <b>114</b> selected to substantially cover the LED chip <b>114</b> and a second dispense portion selected to fill the encapsulant region <b>115</b>. The quantity of the first portion of dispensed encapsulant material may be selected to reduce or prevent the risk of forming bubbles around the LED chip <b>114</b>. As such, as used herein, reference to “substantially” covering the LED chip <b>114</b> refers to covering enough of the structure of the LED chip <b>114</b> so that such a bubble will not generally result when the remaining portion of the encapsulant material dispensed. After the initially dispensed portion of encapsulant material is allowed to settle, the second portion of the encapsulant material may be dispensed into the encapsulant region.

0077Methods of forming LED submounts and packaged LEDs according to some embodiments of the invention are further illustrated in <figref idref="DRAWINGS">FIGS. 9-11</figref>. The methods illustrated in <figref idref="DRAWINGS">FIGS. 9-11</figref> are described with reference to the embodiments illustrated in <figref idref="DRAWINGS">FIGS. 2A-8</figref> above. As illustrated in <figref idref="DRAWINGS">FIG. 9</figref>, some methods <b>500</b> of forming an LED submount according to some embodiments of the invention includes depositing a metal layer on a substrate <b>110</b> (block <b>510</b>); and patterning the metal layer to form a die attach pad <b>112</b>, a first meniscus control feature <b>116</b> surrounding the die attach pad <b>112</b> and defining a first encapsulant region <b>115</b> of the upper surface of the substrate <b>110</b>, and a second meniscus control feature <b>118</b> surrounding the first encapsulant region <b>115</b> and defining a second encapsulant region <b>125</b> of the upper surface of the substrate <b>110</b> (block <b>520</b>).

0078Methods of forming a packaged LED according to some embodiments of the invention are illustrated in <figref idref="DRAWINGS">FIG. 10</figref>. As illustrated therein, methods <b>600</b> according to some embodiments of the invention may include depositing a metal layer on a substrate <b>110</b> (block <b>610</b>) and patterning the metal layer to form a die attach pad <b>112</b>, a first meniscus control feature <b>116</b>, and a second meniscus control feature <b>118</b> (block <b>620</b>). The first meniscus control feature surrounds the die attach pad <b>112</b> and defines a first encapsulant region <b>115</b> of the upper surface of the substrate <b>110</b>, and the second meniscus control feature <b>118</b> surrounds the first encapsulant region <b>115</b> and defines a second encapsulant region <b>125</b> of the upper surface of the substrate <b>110</b>.

0079The method <b>600</b> further includes mounting an LED chip <b>114</b> on the die attach pad <b>112</b> on the substrate <b>110</b> (block <b>630</b>). A first encapsulant material <b>130</b> is then dispensed onto the substrate <b>110</b> and the LED chip <b>114</b> within the first encapsulant region <b>115</b> (block <b>640</b>), and the first encapsulant material <b>130</b> is cured (block <b>650</b>).

0080After curing the first encapsulant material, a second encapsulant material <b>140</b> is dispensed onto the substrate <b>110</b> within the second encapsulant region <b>125</b> (block <b>660</b>), and the second encapsulant material <b>140</b> is cured (block <b>670</b>).

0081In some embodiments, patterning the metal layer includes patterning the metal layer to form a wirebond pad <b>120</b> within the second encapsulant region <b>125</b>. In some embodiments, the method further includes forming a wirebond connection between the LED chip <b>114</b> and the wirebond pad <b>120</b>.

0082As discussed above, some embodiments of the invention include pre-dispensing a quantity of encapsulant material adjacent the LED chip <b>114</b> prior to dispensing the first encapsulant material <b>130</b>. Moreover, a sufficient quantity of the first encapsulant material <b>130</b> may be pre-dispensed to substantially cover the LED chip <b>114</b>. In some embodiments, the first encapsulant material <b>130</b> includes a wavelength conversion material such as a phosphor or a nanocrystal.

0083Patterning the metal layer may further include forming at least one surface feature <b>300</b> between the first and second meniscus control features <b>118</b>. As discussed above, the surface features <b>300</b> may help the encapsulant material adhere to the surface <b>110</b>A of the substrate <b>110</b> and/or cling to the meniscus control features <b>116</b>, <b>118</b>.

0084Referring now to <figref idref="DRAWINGS">FIG. 11</figref>, further methods <b>700</b> of forming a packaged LED according to some embodiments of the invention are illustrated that include depositing a metal layer on a substrate <b>110</b> (block <b>710</b>). The metal layer is patterned to form a die attach pad <b>112</b>, a first meniscus control feature <b>116</b>, a second meniscus control feature <b>118</b> and a third meniscus control feature <b>210</b> (block <b>720</b>). As discussed above, the first meniscus control feature <b>116</b> may surround the die attach pad <b>112</b> and define a first encapsulant region <b>115</b> of the upper surface of the substrate <b>110</b>. The second meniscus control feature <b>118</b> may surround the first encapsulant region <b>115</b> and define a second encapsulant region <b>125</b> of the upper surface of the substrate <b>110</b>. The third meniscus control feature <b>210</b> is formed within the first encapsulant region <b>115</b> and may surround the die attach pad <b>112</b> to thereby define a third encapsulant region <b>215</b> within the first encapsulant region <b>115</b>. The first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b> define a region <b>225</b> in the first encapsulant region <b>115</b> surrounding the third encapsulant region <b>215</b>. It will be understood that for a feature to “surround” a region, the feature need not be continuously formed around the region. Although the figures illustrate continuous features, it may be possible for a meniscus control feature to include gaps or voids therein which do not affect the meniscus control function of the feature.

0085The methods <b>700</b> may further include mounting an LED chip <b>114</b> on the die attach pad <b>112</b> (block <b>730</b>) and dispensing a first encapsulant material <b>230</b> within the region <b>225</b> in the first encapsulant region <b>115</b> defined by the first meniscus control feature <b>116</b> and the third meniscus control feature <b>210</b> (block <b>740</b>). The dispensed first encapsulant material <b>230</b> is cured (block <b>750</b>) and a second encapsulant material <b>240</b> is dispensed onto the substrate <b>110</b> within the third encapsulant region <b>215</b> (block <b>760</b>). The dispensed second encapsulant material <b>240</b> may be cured (block <b>770</b>).

0086Continuing with the discussion of <figref idref="DRAWINGS">FIG. 11</figref>, the methods <b>700</b> may further include dispensing a third encapsulant material <b>250</b> within the second encapsulant region <b>125</b> (block <b>780</b>), and curing the third encapsulant material <b>250</b> (block <b>790</b>).

0087As illustrated above, the dispensed first encapsulant material <b>230</b> may define a cavity <b>220</b> around the LED chip <b>114</b>, and dispensing the second encapsulant material <b>240</b> may include dispensing the second encapsulant material <b>240</b> into the cavity <b>220</b> around the LED chip <b>114</b> after curing the first encapsulant material <b>230</b>. The first encapsulant material <b>230</b>, the second encapsulant material <b>240</b> and/or the third encapsulant <b>230</b> material may include a wavelength conversion material.

0088Some methods of the invention include forming a meniscus extension feature <b>300</b> outside the second encapsulant region <b>125</b> surrounding the second encapsulant region <b>125</b> and defining a encapsulant extension area <b>315</b> of the upper surface of the substrate <b>110</b> (block <b>800</b>), and dispensing a fourth encapsulant material <b>330</b> in the encapsulant extension area <b>315</b> after curing the second encapsulant material <b>140</b> (block <b>810</b>) and curing the fourth encapsulant material <b>330</b> (block <b>820</b>).

0089As discussed above in reference to <figref idref="DRAWINGS">FIGS. 6A-7</figref>, the encapsulant extension area <b>315</b> may have a peripheral shape that is different from a peripheral shape of the second encapsulant region <b>125</b>. For example, the encapsulant extension area <b>315</b> may have a peripheral shape that is oval, circular or generally square or rectangular.

0090The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the appended claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.