JP2006098064A - Probe card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein dispersion of a height position of a probe pin is very difficult to be secured, because a test area for measuring concurrently a large number of items is widened in a wafer test of a semiconductor device and because a probe unit gets thereby large to make the probe unit very difficult to be fixed in parallel. <P>SOLUTION: A gel sheet or a gel interposer sheet containing a gel substance is interposed between the probe unit 11 and a polyimide substrate to fix the probe unit and the polyimide substrate 12. The gel substance is formed into a uniform thickness in a contact face between the probe unit and the polyimide substrate to secure precisely parallelism of the both and to bring further an effect to be fixed stably by adhesion due to surface tension and adhesive force of the gel substance. This probe card 100 of the present invention for measuring concurrently the large number of items capable of making constant a height of the probe pin 10 is provided by this constitution. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a measurement probe card, and more particularly to a probe card capable of simultaneously measuring a large number.

  In the manufacturing process of LSI and VLSI, there is a wafer test process in which after manufacturing a large number of chips on a semiconductor substrate, each chip is tested to be non-defective or defective. In the wafer test process, a test is performed in a state where a probe card is connected to an apparatus called a prober and probe pins of the probe card are connected to electrodes (pads) on the chip surface.

  In these wafer test processes, test efficiency is improved by simultaneously measuring a large number of chips. With the recent VLSI of semiconductor devices, the size of one chip has also increased, and the number of these VLSI chips to be measured simultaneously has increased, so the area to be measured has increased.

  In the wafer test, it is necessary to bring the probe pin of the probe card into contact with the electrode (pad) on the chip surface and make it electrically conductive. To this end, keep the probe card parallel to the semiconductor substrate and adjust the height of the probe pin. It is important to keep it constant. Due to the increase in the number of pins per chip of a semiconductor device and the expansion of a test area for simultaneous measurement of a large number of probes, the probe unit has become enormous and it has become very difficult to fix the probe unit in parallel. As a result, it is very difficult to guarantee the variation in pin height position.

  FIG. 3 shows a conventional probe card for simultaneous measurement of a large number. The multiple simultaneous measurement probe card 101 includes a probe unit 21, probe pins 20, a polyimide substrate 22, and unit fixing screws 23. The semiconductor substrate 50 on which the chip 51 is formed is fixed to the stage 60 by suction. The probe pins 20 are respectively arranged corresponding to the electrodes (pads) of the chip 51.

  The polyimide substrate 22 is provided with wiring for guiding an electrical signal from an electrical test apparatus (tester) (not shown), and is connected to the probe unit 21 by a wiring electrode land. The probe unit 21 provided with the probe pins 20 is fixed to the polyimide substrate 22 with a unit fixing screw 23 and connected to the wiring electrode land of the polyimide substrate 22 by the unit electrode land. Since the unit fixing screw 23 is used as a means for fixing the probe unit 21 to the polyimide substrate 22, when the screw is fixed, if the amount of torque is large, the probe unit 21 is distorted. Varies in height. On the other hand, when the amount of torque is small, fixing of the probe unit 21 to the polyimide substrate 22 becomes unstable and electrical conduction becomes insufficient. For this reason, the management of the torque amount is important, but the management is difficult.

  For example, when N chips are measured simultaneously, the probe unit 21 may have N probe units each having probe pins corresponding to one chip, and may include probe pins corresponding to N / 4 chips. Four probe units may be configured, and one probe unit including probe pins corresponding to N chips can be configured.

  In the wafer test, the stage 60 aligns the probe pin 20 and the corresponding pad of the chip 51 by the stage 60, and then the stage 60 moves up to bring the probe pin 20 and the pad of the chip 51 into contact with each other. This is done by signal. Thereafter, the stage 60 is lowered, step-and-repeat to the position of the next chip to be tested, and then raised again to test the next chip. By repeating these steps, all chips are tested and quality is determined.

  In these tests, if the continuity between the probe pin 20 and the tip electrode is insufficient, the tip is determined to be defective, and it is necessary to ensure a reliable continuity. It becomes important. However, there is a problem that it is difficult to manage when fixing with a unit fixing screw.

  As a solution to these problems, Patent Document 1 discloses a technique in which a reinforcing member is provided at a screw mounting portion of a probe unit. Patent Document 2 discloses a technique for improving contact with a tester side substrate by interposing an elastic sheet between the probe unit and the substrate. In these documents, a probe pin with a coil spring is used, and the height of the probe pin is adjusted by a coil spring or an elastic member and a cylindrical member.

Japanese Patent Laid-Open No. 11-064440 JP 2003-084047 A Japanese Patent Laid-Open No. 08-015316 Japanese Patent Laid-Open No. 11-125646

  However, since these conventional techniques are all fixed with screws, there is a problem that the distortion of the substrate due to the screws cannot be completely eliminated. Further, the probe pin of the prior art includes a coil spring between the first and second probe pins, and the height adjustment between the probe pin and the tip electrode is performed by the coil spring. These probe pins with coil springs are expensive, and the size thereof is larger than that of probe pins without coil springs, and it is difficult to use probe pins with coil springs for highly integrated VLSI. is there. Furthermore, there is a problem that the structure is complicated when the height of the probe pin and the tip electrode is adjusted by an elastic member and a cylindrical member.

  An object of the present application is to solve these problems and provide a probe card capable of simultaneously measuring a large number of probe pins whose height can be adjusted at low cost using probe pins without coil springs.

  The probe card used when testing the semiconductor chip of the present invention has a gel layer between a substrate for transmitting an electric signal from an electric test apparatus and a probe unit having a probe pin.

  The probe card of the present invention is characterized in that the gel layer is provided with a conductive wiring penetrating the gel layer to conduct the probe unit and the probe unit.

  In the probe card of the present invention, the probe unit is fixed to the substrate by a unit fixing jig.

  In the probe card of the present invention, the gel layer has a certain thickness and holds the substrate and the probe unit in parallel.

  In the probe card of the present invention, the gel layer is a modified silicone resin.

  In the probe card of the present invention. The gel layer has a viscosity of 25 Pa · s to 100 Pa · s.

  The probe card used when testing the semiconductor chip of the present invention is a gel card between a substrate for transmitting an electrical signal from an electrical test apparatus and a probe unit having a probe pin in the probe card for testing a semiconductor chip. It is characterized by having.

  In the probe card according to the present invention, the gel sheet is characterized in that the substrate and the probe unit are held in parallel, and further, conductive wiring is provided for conducting the probe unit and the probe unit.

  A probe card used for testing a semiconductor chip of the present invention is a probe card for testing a semiconductor chip, in which a gel is placed between a substrate for transmitting an electrical signal from an electrical test apparatus and a probe unit having probe pins. It has an interposer sheet.

  In the probe card of the present invention, the gel interposer sheet includes a region having a conductive pogo pin for conducting the probe unit and the probe unit, and a gel wall region for holding the substrate and the probe unit in parallel. The substrate and the probe unit are held in parallel by the gel wall region.

  The gel sheet or gel interposer sheet provided between the probe unit on which the probe pin is arranged and the polyimide substrate have the same thickness on the contact surface of both members of the probe unit and the polyimide substrate. In addition to ensuring the degree of accuracy, the gel sheet can be stably fixed by the surface tension phenomenon and adhesive force (adhesive force) of the gel sheet. By bonding the probe unit and the polyimide substrate using a gel sheet or a gel interposer sheet, a probe card for simultaneous measurement can be obtained in which the height of the probe pin can be made constant in a wide area.

  The probe card of the present invention will be described below with reference to the drawings.

  A first embodiment of the present invention will be described with reference to FIG. FIG. 1A is a schematic diagram of a probe card, and FIG. 1B is an enlarged view of a gel sheet.

  The multiple simultaneous measurement probe card 100 of the present invention shown in FIG. 1 (A) includes a probe unit 11, probe pins 10, a polyimide substrate 12, a unit fixing jig 13, and a gel sheet 15. The semiconductor substrate 50 on which the chip 51 is formed is fixed to the stage 60 by suction.

  The polyimide substrate 12 is provided with wiring for guiding an electrical signal from an electrical test apparatus (tester) (not shown), and is further connected to the conductive wiring 17 of the gel sheet 15 by wiring electrode lands. The gel sheet 15 is composed of an insulating medium 16 made of a gel substance and a conductive wiring 17, and is provided between the probe unit 11 and the polyimide substrate 12. The conductive wiring 17 electrically connects the unit electrode land on the upper surface of the probe unit 11 and the wiring electrode land of the polyimide substrate 12. The conductive wiring 17 can be formed as a flexible structure such as a spring or a spring. The insulating medium may be composed of a plurality of layers containing a gel substance.

  The probe unit 11 having the probe pins 10 arranged corresponding to the electrode positions of the chip 51 is fixed to the polyimide substrate 12 by the unit fixing jig 13 and connected to the conductive wiring 17 of the gel sheet 15 by the unit electrode land. . The unit fixing jig 13 is formed in an L shape and fixes the probe unit 21 to the polyimide substrate 22 as a hook. Furthermore, the gel sheet 15 provided between the probe unit 11 and the polyimide substrate 12 has a uniform thickness over the entire contact surface between the probe unit 21 and the polyimide substrate 22 with respect to a constant contact pressure by the unit fixing jig 13. Both parallelisms can be assured with high accuracy and can be stably fixed by the surface tension phenomenon and the adhesive force of the gel.

  A probe capable of stably fixing the probe unit 11 by using the unit fixing jig 13 so as to fix the entire surface of the probe unit 11 with an equal amount of force as the means for fixing the probe unit 11 and utilizing the surface tension phenomenon of the gel sheet 15. The height of the probe pin of the unit 11 can be made constant.

  The probe unit 11 may have, for example, N probe units each having probe pins corresponding to one chip when N chips are simultaneously measured, and probe pins corresponding to N / 4 chips. Four probe units may be configured, and one probe unit including probe pins corresponding to N chips can be configured.

  An electrical signal from the electrical test apparatus (tester) is transmitted to the electrode of the chip 51 via the wiring of the polyimide substrate 12 and the wiring electrode land, the conductive wiring 17 of the gel sheet 15, and the probe pin 10.

  Here, after the alignment between the probe pin 10 and the corresponding pad of the chip 51 is performed by the stage 60, the stage 60 is raised, the probe pin 10 and the pad of the chip 51 are brought into contact with each other, Test by signal. Thereafter, the stage 60 is lowered, step-and-repeat to the position of the next chip to be tested, and then raised again to test the next chip. By repeating these steps, all chips are tested and a pass / fail judgment is made.

  As described above, the peripheral portion of the probe unit 11 is lightly fixed to the polyimide substrate with the gel sheet 15 interposed by the unit fixing jig 13. In order to lightly fix the peripheral portion of the probe unit 11, no distortion is caused by fixing the probe unit 11. Further, by holding the probe unit 11 and the polyimide substrate 12 by the surface tension and adhesive force of the gel sheet 15 interposed between the probe unit 11 and the polyimide substrate 12, the probe unit 11 and the polyimide substrate 12 become parallel. By making the probe unit 11 and the polyimide substrate 12 parallel, the probe pins 20 of the probe unit 11 come into contact with the electrodes of the chip 51 at a constant height, and complete conduction is obtained.

  In this embodiment, the gel sheet 15 is interposed between the probe unit 11 and the polyimide substrate 12, and the probe unit 11 and the polyimide substrate 12 are fixed. Since the gel sheet 15 has a uniform thickness over the entire contact surface between the probe unit 11 and the polyimide substrate 12 due to a constant contact pressure by the unit fixing jig 13, it is possible to guarantee the parallelism between the two with high accuracy, and further, the gel sheet. There is an effect that can be stably fixed by the adhesive force of. With these configurations, a plurality of probe cards for simultaneous measurement can be obtained in which the height of the probe pins can be made constant.

  Example 2 of the present application is shown in FIG. 2A is a plan view, and FIG. 2B is a cross-sectional view taken along line A-A ′. The second embodiment is an improved embodiment of the first embodiment, and uses the gel interposer sheet 30 instead of the gel sheet 15 in the first embodiment. The gel interposer sheet 30 includes a conductive pogo pin 38, a gel wall 39, and a holding sheet 37. The gel interposer sheet 30 is installed between the polyimide substrate 12 and the probe unit 11.

  The conductive pogo pin 38 has the same function as that of the conductive wiring 17 of the first embodiment in connecting the wiring electrode land on the lower surface of the polyimide substrate 12 and the unit electrode land of the probe unit 11. However, the conductive pogo pins 38 are held by the holding sheet 37, and the insulating medium gel wall 39 made of a gel substance does not exist in the region where the conductive pogo pins 38 exist. An area where the conductive pogo pins 38 do not exist is filled with an insulating medium gel to form a gel wall 39. The holding sheet 37 may be made of the same material as that of the gel wall 39, or may be made of a different material, as long as the material has an insulating property.

  A recent VLSI has a narrow pitch between pins, and inevitably a narrow pitch between conductive pogo pins 38. When the gel is filled into the conductive pogo pins having a narrow pitch, the gel rises along the conductive pogo pins, and the gel thickness may not be uniform. For this reason, the insulating medium gel wall 39 is not formed in the region where the conductive pogo pins 38 are present. The gel wall 39 maintains the parallelism between the polyimide substrate 12 and the probe unit 11.

  In this embodiment, an electrical signal from the electrical test apparatus (tester) is transmitted to the electrode of the chip 51 via the wiring of the polyimide substrate 12 and the wiring electrode land, the conductive pogo pin 38 of the gel interposer sheet 30, and the probe pin 10. As a result, the electrical signal from the tester is transmitted to the chip for testing.

  In the present embodiment, the gel interposer sheet 30 is interposed between the probe unit 11 and the polyimide substrate 12, and the probe unit 11 and the polyimide substrate 12 are fixed. Since the gel interposer sheet 30 has a uniform thickness on the contact surface between the probe unit 11 and the polyimide substrate 12 by a constant contact pressure by the unit fixing jig 13, it becomes possible to guarantee the parallelism between the two with high accuracy. Furthermore, there is an effect that the gel wall can be stably fixed by adhesion by surface tension and adhesive force. By adopting these configurations, a plurality of probe cards for simultaneous measurement capable of keeping the height of the probe pins constant can be obtained.

  As a third embodiment of the present invention, a gel material used for the gel sheet and the gel interposer sheet 30 will be described.

  As a material for forming the gel of the present application, a silicon-based resin called a silicone resin can be used. The silicone resin is a silicone resin (silicone rubber) in which an organic group is attached to an inorganic framework such as silicon (Si) and oxygen (O), and these are formed into a polymer. The viscosity is preferably about 20 Pa · s to 100 Pa · s. Here, in order to further enhance the adhesive effect, it may be mixed with another resin (for example, urea type). Furthermore, you may mix a pigment | dye and can mix other resin and a substance as needed, and these are called a modified silicone resin.

  As a method for producing the gel sheet, for example, the gel sheet in Example 1 can be obtained by making silicone rubber into a sheet shape, penetrating metal thin wires through the sheet, coating the gel on both sides thereof, and curing them at about 120 ° C. . Moreover, the gel interposer of Example 2 is obtained by filling a gel in a region where pins are not arranged using a jig surrounding the conductive pogo pins and curing them at about 120 ° C.

  By using the gel substance of the present embodiment, the polyimide substrate and the probe unit can be kept in parallel, and can be stably fixed by adhesion by the surface tension and adhesive force of the gel. Since they can be fixed in parallel, a plurality of probe cards for simultaneous measurement in which the height of the probe pins can be made constant can be obtained.

  Although the present invention has been specifically described above based on the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments and can be variously modified without departing from the gist thereof.

It is the schematic in Example 1 of this application, (A) Whole figure, (B) It is sectional drawing of a gel sheet. It is the schematic of the gel interposer sheet in Example 2 of this application, (A) A top view, (B) It is sectional drawing. It is the schematic in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 20 Probe pin 11, 21 Probe unit 12, 22 Polyimide board 13 Unit fixing jig 15 Gel sheet 16 Insulating medium 17 Conductive wiring 23 Unit fixing screw 30 Gel interposer sheet 37 Holding sheet 38 Conductive pogo pin 39 Gel wall 50 Semiconductor substrate 51 Chip 60 Stage 100, 101 Probe card

Claims (10)

  A probe card used for testing a semiconductor chip, comprising a gel layer between a substrate for transmitting an electrical signal from an electrical test apparatus and a probe unit having probe pins.   2. The probe card according to claim 1, wherein the gel layer is provided with a conductive wiring penetrating the gel layer to make the probe unit and the probe unit conductive.   The probe card according to claim 1 or 2, wherein the probe unit is fixed to the substrate by a unit fixing jig.   The probe card according to claim 3, wherein the gel layer has a certain thickness and holds the substrate and the probe unit in parallel.   The probe card according to claim 1, wherein the gel layer is a modified silicone resin.   The probe card according to claim 5, wherein the gel layer has a viscosity of 25 Pa · s to 100 Pa · s.   A probe card used for testing a semiconductor chip, comprising a gel sheet between a substrate for transmitting an electrical signal from an electrical test apparatus and a probe unit having probe pins.   The probe card according to claim 7, wherein the gel sheet is provided with conductive wiring that holds the substrate and the probe unit in parallel and further conducts the probe unit and the probe unit.   A probe card used for testing a semiconductor chip, comprising a gel interposer sheet between a substrate for transmitting an electrical signal from an electrical test apparatus and a probe unit having probe pins. The gel interposer sheet includes a region having conductive pogo pins for conducting the probe unit and the probe unit, and a gel wall region for holding the substrate and the probe unit in parallel. The probe card according to claim 9, wherein the probe unit is held in parallel.

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