Optoelectronic converter and process of manufacturing

0001The invention relates to an optoelectronic converter with a radiation-emitting and / or receiving Body which is mounted on a carrier unit. It refers especially to such an optoelectronic Converter in which the radiation-emitting and / or receiving body a correspondingly formed semiconductor chip or a polymer luminescent or -Laserdiode is.

0002Such optoelectronic transducer is, for example, known from European Patent EP 4 12 184 B1 and shown in FIG 12th In this known optoelectronic Converter is a radiation detector assembly, which a detector device 39, such as a Photodiode, a common carrier 33, an insulator 34, a fixing member 35, a lens holder 36 and a Lens 37 for focusing of the detector subassembly 39 received radiation. The detector device 39 is with its Bottom mounted on the insulating body 34, which in turn is fastened to the common carrier 33rd The attachment member 35 is adjacent to the insulating body 34 on the common Carrier 33. In the fixing part 35 is by means of a fixing layer 38 of the lens support 36 37 fixed with the lens such that the lens 37 via the beam entrance surface 40 of the detector device 39.

0003The assembly of the individual components of such an optoelectronic Converter is very expensive. It requires a large number of process steps and the adjustment of the Lens 37 is very difficult. In addition, generally occur due to the air gap between the lens 37 and the detector device 39 large reflection losses or aberrations within the on transducer.

0004Furthermore, from the German Offenlegungsschrift DE 43 23 681 discloses an optoelectronic transducer, in which on one side of a light-transmitting support, an optical Receiving or transmitting element and on the other side the carrier, a deflection mirror arrangement and a parallel to Carriers longitudinal axis extending optical fiber are arranged. aüsgesandte The example of an optical transmission element Light penetrates the common carrier, is at the Deflection mirror by 90 ° in the direction of the optical fiber deflected and coupled into this. In the case of a receiving element is the incoming light signal through the optical fiber at the deflection mirror 90 ° towards receiving element distracted, then penetrates the joint Carrier and is coupled into the receiving element.

0005requires also the preparation of these already known arrangement a high installation and adjustment. Conventional Methods for the mounting of semiconductor devices on a PCB can not be used in this arrangement.

0006In addition, an opto-electronic converter with the Known features according to the preamble of claim 1. This previously known converter has a recess in a Carrier plate, in which a radiation emitting body fixed (cf.. JP 05102531).

0007The invention is therefore based on the object, an optoelectronic to DEVELOPED transducer of the type mentioned, the conventional methods of the component mounting mountable insbesondnere suitable for surface mounting , that is in SMD (Surface mounted device) on a printed circuit board can be mounted.

0008At the same time these optoelectronic transducer in a simple Way to produce in large quantities and over other optical devices accurately without great effort be adjustable as well as high efficiency of light extraction exhibit.

0009This object is achieved by an optoelectronic converter with the features of claim 1.

0010Advantageous developments of the invention are the dependent claims 2 to 9. Preferred processes for making a plurality of optoelectronic invention Converters are the subject matter of claim 10.

0011The inventive optoelectronic transducer has over the known optoelectronic described at the outset Transducers has the advantage that it in a simple manner a PCB (z. B. board, ceramic substrate or hybrid substrate) can be fixed by it with its pads set to conductor tracks of the circuit board and the pads by means of an electrically conductive binder be connected to the conductor tracks. The converter therefore such example mounted on a circuit board, that the body between the support member and the circuit board is arranged.

0012In the opto-electronic converter according to the invention is the Radiation-emitting and / or receiving body so on the support unit mounted that its directed radiation outlet surface to mounting surface is. The carrier unit here consists of at least one for a portion of the radiation emitted from the body and / or received radiation permeable material.

0013This has the special tion modifiers leads advantage that the radiation emitted by the body and / or received radiation without much reflection losses and losses due to aberrations in an optical fiber or in a different optical arrangement or in the Body can be coupled.

0014In addition, the invention in which optoelectronic transducer provided that the support unit comprising a carrier plate with a recess, that on a bottom surface of the recess, the mounting surface is provided and that at least partial regions of side walls of the recess are used as connecting parts.

0015The advantage of this feature is, in particular, that in a simple manner, a plurality of the invention optoelectronic converters in composite disk simultaneously can be produced. A separate accurate positioning and mounting of the connecting parts on the carrier plate is not necessary.

0016is In an advantageous development of the invention the carrier plate of an insulating material or is the Carrier plate, optionally in the recess and on the Connecting parts at least partially insulating with a Layer. In the recess and on the connection parts is a number of the electrical contacts of the Radiation-emitting and / or receiving body is connectable, electrically conductive connection tracks provided are structured such that on the connecting portions a number of pads that for surface mounting of the device is suitable formed. This has particular the advantage that the electrically conducting connection tracks in a simple manner by means of conventional methods of semiconductor technology (Mask art + vapor deposition or sputtering of Metal layers, etc.) can be prepared.

0017In a particularly preferred embodiment of the invention optoelectronic transducer, the carrier unit a means for focusing the radiation, whereby advantageously the radiation emitted or received radiation without large losses by total internal reflection at interfaces are coupled to the transducer or eingkoppelt in this can.

0018In another advantageous development of the invention, and their embodiments, the carrier plate an electrically insulating material or is at least partially provided with an insulating layer and are on the carrier plate or on the insulating layer at least applied two structured metallization, arranged on which electrically conductive connecting parts are.

0019This has the particular advantage that the dimensions and the Positions of the electrically conductive connecting parts in a simple located as the dimensions of the mounting surface on the Radiation-emitting and / or receiving body optionally including the connection conductors and / or covering can be adapted to the body.

0020In a further preferred embodiment of the invention optoelectronic transducer is on the body- opposite side of the carrier plate another Plate provided.

0021This makes it possible to the carrier unit of materials having produce different refractive indices, thereby the body height and the optical imaging of the optoelectronic Converter to optimize. In addition, advantageously the other plate means for focusing the radiation exhibit.

0022In a particularly preferred embodiment of the invention optoelectronic transducer is at least the Radiation-emitting and / or receiving body with a Plastic cover or a different type of coverage provided. This is a simple way of body moisture and protected against mechanical damage.

0023Further features, advantages and expediencies of the invention result from the following description of exemplary embodiments in connection with Figures 1, 2 and 6 to 11th

0024Show it:<sl><li>Figure 1 is a schematic sectional view through a first Embodiment of the invention optoelectronic transducer with a recess in a Support plate;</li><li>Figure 2 is a schematic representation of a plan view of the optoelectronic transducer of Figure 1;</li><li>Figure 3 to better understand and to compare a schematic cross sectional view showing an optoelectronic Converter without a recess in the carrier plate;</li><li>Figure 4 is a schematic representation of a plan view of the optoelectronic transducer of Figure 3;</li><li>figure 5 for better understanding and comparison is a schematic sectional view through a further opto-electronic transducer without a recess in the Support plate;</li><li>Figure 6 is a schematic sectional illustration of a second Embodiment of an inventive optoelectronic converter;</li><li>Figure 7 is a schematic representation of a plan view of the optoelectronic transducer of Figure 6;</li><li>Figure 8 is a schematic sectional view of a third Embodiment of an inventive optoelectronic converter; </li><li>Figure 9 is a schematic diagram for explaining a Process sequence for producing a plurality of the invention optoelectronic transducers according to Figure 8 and</li><li>Figures 10 and 11 are schematic diagrams for explaining a method of manufacturing a plurality of the invention optoelectronic transducers according to FIG. 6</li></sl>

0025In the figures, like components are of different Embodiments with the same reference characters provided.

0026has The optoelelektronischen converter of Figure 1 and 2 the support unit 2 a support plate 7 having a trapezoidal Recess 8. On the bottom surface 9 and the side faces 10,11 of the recess 8 and on the upper sides 24, 25 the connecting parts 4.5 are two separate electrically conductive connection tracks 12,13 example in the form applied by metallization. On the connecting parts 4.5 are characterized two pads 16,17 of the optoelectronic Converter formed.

0027On the bottom surface (9) of the Recess 8 is a radiation emitting and / or receiving body 1 mounted such that its bottom-contact 22 at least partially on the electrically conductive connecting web 12 rests and with this for example by means of an Au-Sn solder or by means of a joined other suitable electrically conductive binder is. A top contact 23 of the body 1 by means a connection conductor 26 (eg. as a bonding wire) with the electrically conductive connecting web 13.

0028The body 1 is for example a light emitting diode, a photo diode (PIN Fotodoide) or a Vertical Cavity Surface Emitting Laser (VCSEL).

0029The carrier plate 7 is electrically insulating and is, for example from a for the radiation emitted by the body 1 or received radiation transmissive glass, plastic, sapphire, Diamond or semiconductor material. For wavelengths λ> 400 nm, for example, SiC, for λ> 550 nm GaP for λ> 900 nm GaAs and for λ> 1100 nm, silicon can be used. The recess 8 is, for example, by etching, sawing or milling produced. Likewise, an electrically conductive Carrier plate 7 used be, but then the in the recess and on the connecting parts 4.5 at least partially with an insulating layer provided 15 (z. B. an oxide layer or plastic layer, etc.) is.

0030The electrically conductive connection tracks 12, 13 consist, for example, of aluminum, of an aluminum-based alloy or from a Au multilayer system. It is also conceivable that in The case of using a support plate 7 made of a semiconductor material in the recess 8, as well as on the upper sides 24, 25 of the connecting parts 4, 5 by means of suitable doping Connecting tracks are formed. For producing such Doping can the ordinary skill today known methods of semiconductor technology, such as Ion implantation may be used.

0031Between the radiation exit and / or -eintrittsfläche 6 of the body 1 and the support plate 7 is to improve the light extraction from the body 1 or from the Support plate 7, an optical coupling medium 29, for example, a casting resin. based Improving light outcoupling , Occurs due to an increase of the angle at which total reflection. As essential feature, the coupling medium 29 only a low absorption of from 1 Halbbleiterchip emitted and / or received radiation.

0032The sake of completeness should be mentioned at this point that the radiation exit and / or 6 of -eintrittsfläche Radiation emitting body 1 is the surface by which the largest percentage of the radiation generated in the body 1 emerging therefrom. Analogously, the radiation entrance area a radiation receiving body 1 that surface, through which a received radiation into the body 1 enters.

0033The pads 16,17 define a contact plane (Indicated by the dashed line 14), whose distance to the bottom surface 9 is greater than the maximum height of the Body 1 including connecting conductors 26 and an optional provided chip cover 27, for example, from a with quartz beads or flakes filled resin or from an acrylate. The chip cover 27 serves in particular to the body 1 against humidity and mechanical to protect damage.

0034On its recess 8 opposite side, the Support plate 7 a means 21 for focusing of the body 1 emitted and / or received radiation, eg. B. a spherical lens, an aspherical lens or a diffractive optics. This can, for example, by etching or Loops formed in the carrier plate 7 or prepared separately and for example by soldering, adhesive bonding or anodic Bonding be applied to the carrier plate. 7

0035The optoelectronic shown in the figures 3 and 4 converter, the part of the invention is not, , the carrier plate 7 is a planar top 28 , on which the electrically conducting connection tracks 12, 13 are applied. The support plate 7 can be made of an electrically insulating material be fabricated (eg. B. Material as in the above embodiment of Figure 1 and 2) his or electrically conductive, then at least partially with an electrically insulating layer (eg. B. Oxide layer or plastic layer, etc.) is provided.

0036As in the embodiment of Figures 1 and 2 Also here the body 1 in such a manner on a mounting surface 3 of the Carrier plate 7 is fixed, that it comprises at least a portion its base contact 22 on the electrically conductive Connecting track 12 rests with these electrically conductive connected is. On the electrically conductive connection tracks 12,13 for example, by soldering or gluing connection parts 4 ', 5' are fastened, which are electrically conductive so that the top sides 24, 25 of the connecting parts 4 ', 5', the electrical Pads 16 ', 17' of the optoelectronic converter form.

0037The connecting parts 4 ', 5' for example consist of high conductivity Silicon, metal or other material having high electrical conductivity. As a binder between the connecting parts 4 ', 5' and the electrically conducting connection tracks 12,13 For example, a metallic solder or an electrically conductive plastic is used. As well can the connecting parts 4 ', 5' by means of eutectic bonding be attached to the connecting tracks 12,13.

0038As materials for the support plate 7 and the electrically conductive connection tracks 12, 13 are, for example correspondingly with respect to the former embodiment, specified materials.

0039The carrier plate 7 has also on its body 1 opposite A side means 21 for focusing of the body of the emitted and / or received radiation. Representative of this is shown a diffractive optics in FIG. 3

0040Moreover, also in this embodiment the Body 1 by means of a chip covering 27 against moisture be and protected against mechanical damage (Materials for the chip cover 27 as indicated above to Figure 1).

0041The embodiment of Figure 5, the part of the invention is not, differs from the of Figures 3 and 4, characterized in that on the mounting surface opposite side of the support plate 7, a further Plate 18 is arranged. The other plate 18 is for example, from a different material as the carrier plate 7. With a suitable selection of these materials, eg. As glass for the support plate 7 and silicon for another plate 18, , the high frequency characteristics of the transducer improves and reduce the capacity of the optoelectronic converter will. In addition, by different refractive indices the other plate 18 and the support plate 7, the height of and the optical image of the opotelektronischen converter be optimized.

0042As shown in Figure 5, here the support plate 7, but the other plate 18, a means 21 for focusing of the radiation, in this case, a spherical or a aspherical lens 28.

0043The embodiment of Figures 6 and 7 differs from the embodiment shown in Figures 1 and 2 characterized in that the recess in the carrier plate 8 7 of a nascent form of the narrower from top to bottom Grube has, for example, produced by etching is. When connecting parts 4.5 Here are portions of the Sidewall of the pit used. This has the advantage that the Pads 16, 17 in beliegiger arrangement on top the side wall of the pit may be arranged, whereby For example, the design of the tracks on a the optoelectronic transducer associated PCB is less restricted.

0044On the connection tracks 12,13 can electrically conductive connecting parts 4 ', 5' (z. B. called silicon jumper chips) with pads 16 ', 17' may be mounted, the pads realized 16 ', 17', for example in the form of metal layers are.

0045On the opposite side of the pit of the support plate 7 is in this embodiment as a means 21 for focusing the radiation a separately prepared spherical or aspherical lens, for example, applied by gluing. Instead of the spherical or aspherical lens applied a diffractive optics separately produced or be formed in the carrier plate. 7 The latter is of course, to the spherical or aspherical Lens.

0046In the embodiment of Figure 8, the support plate 7 is substantially identical to the carrier plate of Figure 1 formed (compare the related description). Similarly, the carrier plate can analogous to the embodiment be embodied by FIG. 6 and 7 In addition to the support plate 7, the support unit 2 here, however, another plate 18 on, in which a means 21 adapted for focusing the radiation is or can be applied.

0047Using the plots shown in Figure 9 is the following the procedure for the simultaneous production a plurality of optoelectrochemical Sichen transducers according to the Figure 8 illustrates:<ul><li>First, in a support disk 30 made of the material for the support plates 7 (here, for example, glass) is, for example, by etching or milling a Plurality of recesses made. 8</li><li>Below are some areas on the surface of the Carrier disk 30, for example by means of a mask technique and Vapor deposition or sputtering, a plurality of connecting tracks 12,13 applied.</li><li>As the next step in the recesses 8 a plurality fixed body 1 and their contacts with 22,23 the connection tracks 12,13 z. B. by an electrically conductive solder or by means of connecting conductors 26 (bonding wires) electrically connected.</li><li>If necessary, then the gaps between are the radiation exit faces of the body 1 and the carrier plate 30 each with a coupling medium 29 (z. B. resin) filled. This can, for example, by means of a micro dosing done with the coupling medium directly into the intermediate space is injected.</li><li>can subsequently, if provided, the recesses 8 are filled with a casting resin or with an acrylate, so that the body 1 including connecting conductors 26 each are provided with a chip covering 27th</li><li>Separately from the preparation of the support disk 30 with the Bodies 1, a disk 31 of material from the Disk 18 of Figure 8, eg., Silicon, is, with a provided plurality of means 21 for focusing the Stahlung (Manufacturing process as indicated above) are.</li><li>The disc 31 is then mixed with the carrier plate 30, for example, by soldering, gluing or anodic bonding connected. but Also the disk 31 before already mounting the body 1 on the carrier disk 30 with this get connected. The composite disk is then z. B. sporadically by means of sawing.</li><li>Before the separation of the laminated structure the optoelectrochemical Sichen can Transducers are electrically tested and visually.</li></ul>

0048In the illustrated below with reference to Figures 10 and 11 A method for fabricating a plurality of electro-opto Sichen For transducers according to Figures 6 and 7 is analogous to the above The method described a carrier disc 30 initially with a plurality of recesses 8 provided on the top the support sheet 30 a plurality of connecting tracks 12,13 applied and in the recesses a plurality of body 1 attached. As regards connection of the electrical contacts the body 1 with the connecting tracks and with regard to the coupling medium and chip cover applies also the same as in Reference given to FIG. 9

0049The difference from the aforementioned method is firstly that here the means 21 for focusing the radiation formed in the support disk or applied to this be and secondly in pairs on the connection webs together connected electrically conductive connecting parts 4 ', 5' (Connecting part couples 32) with connecting surfaces 16 ', 17' (For example, metal layers) are applied. subsequently the carrier plate 30 together with the connector pairs 32 possibly after electrical and / or optical testing the converter singulated into individual optoelectronic converter.