Probe card and its manufacturing method

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a probe card used for testing a plurality of semiconductor integrated circuits formed on a semiconductor wafer in a wafer state, such as energization, and a method for manufacturing the probe card.

【0002】

[Conventional technology]

In recent years, remarkable progress has been made in miniaturization of electronic devices, and there is an increasing demand for miniaturization of semiconductor integrated circuits mounted on electronic devices. In response to such demands, a method of mounting a semiconductor integrated circuit directly on a circuit board has been developed in a state of being cut out from a semiconductor wafer, that is, in a state of a bare chip. Therefore, it is desired to supply bare chips with guaranteed quality.

【0003】

In order to guarantee the quality of bare chips, it is necessary to perform burn-in screening of all semiconductor integrated circuits in the state of bare chips. In order to carry out this process efficiently, it is required to perform burn-in screening in a batch in the state of the wafer before cutting out the bare chip. In order to perform burn-in screening for bare chips in a wafer state at once, it is necessary to simultaneously apply a power supply voltage and a signal to a plurality of chips formed on the same wafer to operate the plurality of chips. .. For this purpose, it is necessary to prepare a probe card having several thousand or more probes, but there is a problem that the conventional needle type probe card cannot cope with the number of pins and the price.

【0004】

Therefore, a probe card in which a fine spring is formed on a substrate by wire bonding is disclosed in Japanese Patent Application Laid-Open No. 10-506197 and JP-A-2000-67953. The probe of this probe card is formed by plating a soft metal at a time after being formed by wire bonding, so that some parts of the probe formed in thousands are defective or used repeatedly. When a later partial defect occurs, only the defective part cannot be partially repaired.

【0005】

[Problems to be Solved by the Invention]

In order to solve the above problems, the applicant proposed in Japanese Patent Application No. 2000-186584 a probe card in which a probe as shown in FIG. 4 is soldered to a pad formed on a wiring board. In FIG. 4, 1 is a wiring board, 2 is a pad, 3 is a probe, 3a is a fixed part, 3b is a deformed part, 4 is a solder, and an appropriate amount of solder 4 is pre-applied on the pad 2. .. Specifically, for example, in a state where the solder 4 is melted by a heating means (not shown) using a laser beam or the like, the solder 4 is formed into a shape having a fixed portion 3a and a deformed portion 3b in advance, and then the solder wettability is improved and oxidation prevention is performed. The probe 3 plated with gold for the purpose is held by a holding means (not shown), lowered while controlling the position, inclination, and height, and after confirming the position and inclination height on the pad 2, it is heated. The probe 3 is joined to the pad 2 by stopping the means.

【0006】

However, in such a probe card, since the area of the wiring board 1 is larger than that of the probe 3, the temperature of the probe 3 rises faster than that of the pad 2 of the wiring board 1 due to heating by the heating means. Therefore, as shown in FIG. 5, most of the solder 4 runs up to the fixed portion 3a of the probe 3, and the remaining amount on the pad 2 is small, so that the bonding strength is weakened.

【0007】

An object of the present invention is to provide an appropriate strength for bonding a pad and a probe in a probe card for batch inspection of wafers in which a part of the probes can be repaired.

【0008】

[Means for solving problems]

In order to solve the above problems, the invention according to claim 1 is, for example, as shown in FIG. 1, a probe card for testing a plurality of semiconductor integrated circuits formed on a semiconductor wafer, and is used for each inspection of the semiconductor wafer. A plurality of connecting members (for example, a probe 3) to be connected to an electrode and a wiring means (for example, a wiring substrate 1) electrically connected to the connecting member are provided, and the connecting member is formed on the wiring means. A wettability reducing portion (for example) that reduces the wettability of the solder to the fixed portion (3a) that is soldered to the joint portion (for example, pad 2) and is soldered to the joint portion of the connecting member. It is characterized by providing a hole 3c).

【0009】

Here, the connecting member may be any one that connects the wiring means and the semiconductor integrated circuit so that a power supply voltage, a signal, or the like can be simultaneously applied to a plurality of semiconductor integrated circuits from the wiring means, for example, a probe or the like. Can be mentioned. The wiring means may be, for example, a wiring board or the like that is wired so as to conduct a power supply voltage, a signal, or the like to each semiconductor integrated circuit. The joint portion may be any one that has electrical conductivity and can join the connecting members by soldering or the like, and examples thereof include a metal pad.

【0010】

According to the invention of claim 1, since the probe card includes a connecting member and a wiring means, and the connecting member is joined to a joint formed on the wiring means, the probe card may be used repeatedly. As a result, when a defect occurs in a part of the connecting members, only the defective connecting member can be easily removed from the joint portion, and a new connecting member can be easily joined to the joint portion. Therefore, it is possible to repair the defective connecting member one by one without removing all the connecting members from the wiring means. Further, by providing a wettability reducing portion on the connecting member and joining the connecting member to the joint portion by soldering, the wettability of the solder is reduced, the run-up of the solder is appropriately suppressed, and the connecting member is surely suppressed. Can be joined to the joint.

【0011】

The invention according to claim 2 is the probe card according to claim 1, wherein the joining member is formed by molding a hard metal into a predetermined shape and plating the probe card.

【0012】

Examples of hard metals include metals such as nickel, chromium, and iron, or alloys containing them as main components.

【0013】

According to the invention of claim 2, since the connecting member according to claim 1 is formed by molding a hard metal into a predetermined shape and plating it, a soft metal such as gold is formed and plated by wire bonding. Unlike the connecting member formed by the treatment, even when a partial defect occurs in the connecting member, only the defective part can be partially repaired.

【0014】

The invention according to claim 3 is the probe card according to claim 1 or 2, characterized in that, for example, as shown in FIG. 1, the connecting member has a structure that elastically deforms (for example, a deformed portion 3b). It is supposed to be.

【0015】

According to the invention of claim 3, since the connecting member according to claim 1 or 2 is an elastically deformable probe card, the connecting member sufficiently applies the pressure generated by pressure contact between the semiconductor integrated circuit and the connecting member. Can be absorbed. From this, it is possible to absorb more pressure than necessary and bring the connecting member into contact with the semiconductor integrated circuit at an appropriate pressure.

【0016】

The invention according to claim 4 is the probe card according to claim 3, wherein the connecting member has a substantially S-shaped shape, for example, as shown in FIG.

【0017】

According to the invention of claim 4, since the connecting member according to claim 3 is a probe card having a substantially S-shaped shape, not only the pressure due to pressure contact but also the force acting in the direction orthogonal to the pressure direction is applied. Can be sufficiently absorbed.

【0018】

The invention according to claim 5 is the probe card according to claim 1, for example, as shown in FIG. 1, the wettability reducing portion is a hole (3c) formed on a side surface of the fixed portion. It is a feature.

【0019】

According to the invention of claim 5, by providing the hole in the connecting member, the heat for melting the solder is dissipated in the hole and prevented from being transmitted to the connecting member. Therefore, the wettability of the solder is reduced, and the run-up of the solder can be appropriately suppressed.

【0020】

The invention according to claim 6 is the probe card according to claim 1, for example, as shown in FIG. 3, the wettability reducing portion is a partially plated portion or a partially coated portion (3d) applied to the fixed portion. It is characterized by being.

【0021】

According to the invention of claim 6, the run-up of the solder can be appropriately suppressed by partially plating or partially coating with a material that reduces the wettability of the solder.

【0022】

The invention according to claim 7 is a method for manufacturing a probe card for testing a plurality of semiconductor integrated circuits formed on a semiconductor wafer, which comprises a step of forming a connecting member to be connected to each inspection electrode of the semiconductor wafer. It is characterized by having a step of joining the formed connecting member to the joint portion formed on the wiring means.

【0023】

According to the invention of claim 7, since the probe card is manufactured by having a connecting member forming step and a joining step, the connecting member can be formed and formed one by one without being joined to the wiring means. The connected connecting members can be joined to the joint in units of one. As a result, the defective joining member can be replaced or repaired one by one.

【0024】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

【0025】

<Example of First Embodiment> In FIG. 1, 1 is a wiring board (wiring means), 2 is a pad (joint portion), 3 is a probe (contact member), and 4 is solder.

【0026】

The wiring board 1 has a plurality of wirings (leads) for simultaneously applying a power supply voltage, a signal, or the like for testing energization of a plurality of semiconductor integrated circuits formed on a semiconductor wafer to the semiconductor integrated circuits. doing. Further, as shown in FIG. 1, a plurality of (for example, several thousand) pads 2 are formed on the surface of the wiring board 1, and each wiring corresponds to the corresponding pads 2 so that the test can be appropriately performed. It is connected to the.

【0027】

The pad 2 is joined to a probe 3 described later, and a metal layer is coated on the surface of the wiring board 1. Further, the pads 2 are formed at positions corresponding to the semiconductor integrated circuits so that all the plurality of semiconductor integrated circuits formed on the semiconductor wafer can be easily tested.

【0028】

The probe 3 is in pressure contact with each inspection electrode of the semiconductor wafer, and supplies a signal or the like output from the wiring board 1 to each semiconductor integrated circuit. As shown in FIG. 1, the probe 3 is formed of a hard metal such as nickel or an alloy thereof, and is formed on a semiconductor wafer with a fixed portion 3a bonded to the pad 2 and a deformed portion 3b that deforms when pressure is applied. It has a pressure contact portion 3e that makes pressure contact with the semiconductor integrated circuit. The pad joint portion 3a has a flat bottom surface and is thickly formed so as to extend downward so that it can be easily joined to the pad 2, and a hole (wetness reducing portion) 3c is formed on the side surface. The deformed part 3b is curved and has a substantially S-shape. The pressure contact portion 3e has a flat upper surface and a shape that protrudes upward so as to facilitate pressure contact with the semiconductor integrated circuit.

【0029】

The probe 3 is molded into the above shape with a hard metal such as nickel or its alloy, and then metal-plated by electroplating, electroless plating, etc. in order to prevent oxidation and improve solder wettability. Formed by

【0030】

Since the probe 3 has the above-mentioned shape and is made of a hard metal, the probe 3 elastically deforms when an external force is applied to the probe 3. That is, the probe 3 has elasticity. Since the probe 3 has elasticity, the pressure acting in the direction perpendicular to the contact surface when the probe 3 comes into pressure contact with the semiconductor integrated circuit on the semiconductor wafer is absorbed by the elastic deformation of the probe 3. Therefore, the probe 3 can come into contact with the semiconductor integrated circuit at an appropriate pressure by absorbing more pressure than necessary. Further, since the probe 3 has the above-mentioned shape, the force acting in the direction orthogonal to this pressure is sufficiently absorbed. As a result, the contact surface between the pressure contact portion 3e of the probe 3 and the semiconductor integrated circuit is not displaced.

【0031】

Next, a method of joining the probe of the probe card will be described. First, as shown in FIG. 1, an appropriate amount of solder 4 is applied to the pad 2 on the wiring board 1, and the solder 4 is melted by a heating means (not shown) such as a laser beam. The hard metal is molded in advance as described above, the probe 3 independently formed by the plating method is held by a holding means (not shown), and the probe 3 is lowered while controlling the position, inclination, height, etc. Contact with molten solder 4. After confirming the position, inclination, height, etc. on the pad 2, the probe 3 is joined to the pad 2 by stopping the heating means.

【0032】

At this time, the heat is blocked by the hole 3c formed in the fixed portion 3a of the probe 3, and the heat is suppressed from being transferred to the upper part of the probe 3. As a result, the wettability of the solder 4 is reduced, the solder 4 forms a fillet between the fixed portion 3a and the pad 2 as shown in FIG. 2, and the probe 3 is securely joined to the pad 2. The probe 3 may be joined to the pad 2 one by one or a plurality of probes 3 at a time.

【0033】

<Example of Second Embodiment> In FIG. 3, the wiring board (wiring means) 1, the pad (joint) 2, the probe (contact member) 3, and the solder 4 are the same as those in the first embodiment. In this embodiment, a partially plated portion plated with a material that reduces the wettability of solder such as nickel or a coated partially coated portion 3d is formed on the upper portion of the fixed portion 3a of the probe 3.

【0034】

That is, when joining the probe 3 of the probe card, the wettability due to the thermal melting of the solder 4 is reduced by the partially plated portion or the partially coated portion 3d provided on the fixed portion 3a of the probe 3, and the first embodiment example. Similarly, the solder 4 forms a fillet between the fixed portion 3a and the pad 2, and the probe 3 is securely joined to the pad 2.

【0035】

In this way, it is possible to appropriately suppress the solder running up to the probe due to the difference in heat dissipation between the probe 3 and the wiring board 1, so that the probe 3 can be reliably joined. In addition, since the probe 3 is joined to the pad 2 formed on the wiring board 1, when a defect occurs in some of the probes 3 such as when the probe card is used repeatedly, only the probe in which the defect occurs Can be easily removed from the pad 2, and the newly formed probe 3 can be easily joined to the pad 2. As a result, the defective probe 3 can be repaired one by one without removing all the probes 3 from the wiring board 1.

【0036】

In the above embodiments, the hard metal is nickel, an alloy thereof, or the like, but the present invention is not limited to this, and other hard metals may be used. Further, although nickel plating is used as the partial plating portion or the partial coating portion, partial plating or partial coating may be performed using another material that reduces the wettability of the solder. In addition, it goes without saying that the specific detailed structure and the like can be changed as appropriate.

【0037】

[Effect of the invention]

According to the invention of claim 1, the connecting member and the wiring means are provided, and the connecting member is joined to the joint portion formed on the wiring means, so that the connecting member can be attached to a part of the connecting member of the probe card. When a defect occurs, only the defective connecting member can be easily removed from the joint, and a new connecting member can be easily connected to the joint, so that all the connecting members do not have to be removed from the wiring means. In addition, there is an advantage that the defective connecting member can be repaired one by one. In addition, the connecting member is joined to the joint by soldering, and the connecting member is provided with a wettability reducing portion that reduces the wettability of the solder, so that the run-up of the solder is suppressed and the connecting member is reliably joined. It also has the advantage of being able to join to the part.

【0038】

According to the invention of claim 2, in addition to the effect obtained by the invention of claim 1, the connecting member is formed by molding a hard metal into a predetermined shape and plating. Unlike the connecting member formed by forming the soft metal by wire bonding and plating, it has the advantage that even when a partial defect occurs in the connecting member, only the defective part can be partially repaired. ..

【0039】

According to the invention of claim 3, the connecting member can sufficiently absorb the force generated by the pressure contact between the semiconductor integrated circuit and the connecting member due to the elastic deformation of the connecting member. In addition to the effects obtained by the invention described in 1 or 2, it is possible to obtain an advantage that the connecting member can come into contact with the semiconductor integrated circuit at an appropriate pressure by absorbing more pressure than necessary.

【0040】

According to the invention of claim 4, since the connecting member has a substantially S-shaped shape, in addition to the effect obtained by the invention of claim 3, it acts in a direction orthogonal to the pressure direction due to pressure contact. It has the advantage of being able to absorb enough force.

【0041】

According to the invention of claim 5, since the hole of the connecting member blocks the heat of melting the solder, the upper part of the connecting member is not unnecessarily warmed. As a result, the wettability of the solder is reduced, so that there is an advantage that the run-up of the solder can be appropriately suppressed and the connecting members can be reliably joined.

【0042】

According to the invention of claim 6, the run-up of the solder can be appropriately suppressed by the partially plated portion or the partially coated portion using a material that reduces the wettability of the solder. This has the advantage that the connecting members can be reliably joined.

【0043】

According to the invention of claim 7, the connecting member can be formed one by one in a state where the connecting member is not joined to the wiring means by the connecting member forming step and the joining step, and one connecting member is formed. Since it can be joined to the joint in units, there is an advantage that the defective connecting member can be replaced or repaired one by one.

[Simple explanation of drawings]

[Figure 1]

As an example of the first embodiment to which the present invention is applied, it is a partial perspective view which shows the structure of the probe card using the probe provided with a hole.

[Figure 2]

It is sectional drawing which shows the bonding state with the pad of the probe in FIG.

[Fig. 3]

As an example of the second embodiment to which the present invention is applied, it is a partial perspective view which shows the structure of the probe card using the probe which was partially plated or coated.

[Fig. 4]

It is a partial perspective view which shows the structure of the probe card which is a premise.

[Fig. 5]

It is sectional drawing which shows the bonding state with the pad of the probe in FIG.

[Explanation of symbols]

1 Wiring board (wiring means) 2 pads (joints) 3 Probe (connecting member) 3a fixed part 3c hole 3d partial plating or partial coating 4 solder