KR200221077Y1 - Conductive polymer probe card - Google Patents

Abstract

The present invention relates to a probe card for determining whether an electronic component is normal or defective, and integrated with an IC chip integrated in a wafer in a semiconductor production process. The present invention comprises an elastic conductive polymer probe and an electrical connection means. It is characterized by. The elastic conductive polymer probe of the present invention sufficiently withstands the overdrive applied to the probe during the wafer test process. In addition, since the conductive polymer probe of the present invention is disposed in a mirror image with the bonding pad of the IC chip, there is no limitation in the arrangement of the bonding pad to be measured. The probe card having the conductive polymer probe and the connecting means according to the present invention has one or more IC chips having a high-density bonding pad, and more preferably, wafer level probing.

Description

Conductive polymer probe card

The present invention relates to a probe card for determining whether an electronic component is normal or defective, and more widely, an integrated circuit (IC) chip integrated in a wafer in a semiconductor production process. After the semiconductor integrated circuit is implemented on the wafer, the wafer test is performed to verify the operation state of the IC chip in the wafer state. The probe card used for this purpose is the part that connects the test pad of the IC chip with the test equipment.

The purpose of the wafer test process using a probe card is to select IC chips for defects and remove them in a subsequent process, improve the yield by repairing chips that can be repaired among the chips in which the defects occur, and analyze the cause of each unit to analyze the cause of each unit. This is done in order to prevent a large amount of defects by feedback, and to reduce the cost of assembly and inspection of subsequent processes by removing the defective IC chip.

Probe cards should have the following characteristics: First, the probe on the probe card must be stressed enough to apply sufficient force to the IC pad to be measured. A natural oxide film is formed on the IC chip pad made of aluminum. For testing, this oxide layer must be drilled and contacted with the underlying metal. Therefore, the probe card must be able to apply enough force to the IC pad to penetrate this oxide layer. Second, the probe card should have a short distance from the contact with the IC pad to be measured to the input of the test equipment. The longer the length, the more difficult the impedance adjustment and the larger the reflection noise, which distorts the input and output waveforms of the tester, making it impossible to test at high frequencies, especially during AC testing. Third, each contact must make a perfect contact individually when in contact with the IC pad. If this is not guaranteed, it can be determined that the circuit is open and a good chip can be wrongly judged as defective. Fourth, the probe card should have a constant and small contact resistance and impedance. If the impedance changes during the test, the input of the chip will change, which will prevent accurate testing. Fifth, since a probe card is a consumable, it should have a long life. Probe cards are in constant physical contact with the pads of the IC chip being measured, resulting in mechanical wear. Therefore, if the probe card has a short lifespan, the test cost will increase.

1 is a plan view illustrating a conventional probe card. The probe tip 2 is connected to the IC chip pad 1 formed on the IC chip of the semiconductor element, and the probe tip is fixed to the probe card 3 by an adhesive such as epoxy. The above-described probe card is a horizontal probe card, which is difficult to adjust the position of the probe due to the manual manufacturing process, and the production time is long and the defect rate is not suitable for mass production. In addition, as the size of the device becomes relatively small according to the high function and integration of the semiconductor device, the size of the pad and the spacing between the pads are narrowed. There is a limit in reducing the size of the bonding pad with a conventional horizontal probe card. Conventional horizontal probe cards allow the tip of the probe to be stressed so that each probe tip can withstand the overdrive applied to make a perfect contact individually with the multiple pads of the IC chip. It is bent, and it is very difficult to control the stress of the probe, and due to the length of the probe, it is easy to generate reflection noise due to poor impedance control.

An object of the present invention is to provide a proof card that satisfies all the characteristics of the probe card as described above using a conductive polymer as a probe, and solves the problems of the prior art.

1 is a plan view of a conventional probe card

2 is a cross-sectional view of a probe card having conductive polymer probes and electrical connection means;

3 is a rear plan view of the photosensitive glass substrate;

4 is a cross-sectional view of the probe card deposited with a metal film on top of the conductive polymer

5 is a cross-sectional view of a mirror image of a probe card and an IC chip bonding pad.

(1) IC chip pad

(2) probe tip

(3) probe card

(4) photosensitive glass substrate

(5) conductive polymer

(6) metal swabs

(7) metal wiring

(8) metal film

(9) wafer

The present invention for achieving the above object is a probe card body consisting of a photosensitive glass substrate, a probe made of a conductive polymer and a metal film formed on one surface of the probe card body, which is a means for connecting the probe and external test equipment Provided is a probe card characterized by a metal swab penetrating the body of the probe part card.

The probe card proposed in the present invention to satisfy the characteristics required by the probe card is shown in FIG. 2. In detail, a probe 5 made of a conductive polymer and a metal swab 6 and a metal wiring 7 serving as a means for connecting the probe to external test equipment are formed on the body of the probe card made of the photosensitive glass substrate 4. It can be seen that it is formed.

4 shows metal wiring formed on one surface of the photosensitive glass substrate. The probe can be adjusted in the formation position and number according to the position and the number of the pad to be corresponding.

As described above, in order for the plurality of probes to be electrically connected to the pads of the IC chip, an overdrive must be applied to the probe card because the heights of the probes do not coincide exactly. Conventional probe cards bend the tip of the needle (Needle) or form a probe on a thin, elastic membrane (Membrane) to allow the probe to have a stress. In the present invention, the conductive polymer having such stress can be used as a probe to withstand the overdrive applied from the outside, and the connection between the probe and the external test equipment is made by using a metal swab formed on the probe card main body. The short distance to the input of the test equipment was solved and the electrical connection problem was solved.

An example of a process for manufacturing a probe card for semiconductor device inspection proposed in the present invention is as follows. Photolithography and wet etching are performed on the probe card body made of the photosensitive glass substrate to form a metal swab that serves as a connection means between the probe and the external measuring equipment to form a hole penetrating the photosensitive glass substrate. Silk printing or plating is used to form metal swabs and metal wirings are formed on one side of the photosensitive glass substrate. Probes made of a conductive polymer are formed on the top of the metal swab on the other side of the photosensitive glass substrate using a dispensing method or photolithography. At this time, the metal film 8 may be deposited on the top of the probe in order to improve electrical contact between the IC chip pad and the probe on the top of the probe made of the conductive polymer. This is shown in FIG. 4. The one-to-one correspondence between the probe card for semiconductor device inspection and the IC chip pad proposed in the present invention is shown in FIG. 5.

In the present invention, the fabrication of the probe card for semiconductor device inspection is performed by using a conductive polymer so that the overdrive applied to the probe card during the wafer test process can be sufficiently to verify the operation state of the IC chip. Probe formation is made using technology, which enables the manufacture of probe cards that can be directly matched one-to-one with the pad to be tested, regardless of the type or shape of the IC chip. In addition, the use of the photosensitive glass substrate as the main body of the probe card has the advantage of easy alignment with the IC chip. In addition, since the wafer can be manufactured in units of wafers, the wafer-level test can be performed with a high density of probes.

Claims (4)

With the probe card body, A through hole formed in the probe card body, A metal swab filled in the through hole, A conductive polymer probe connected to one side of the metal swab, A probe card comprising a metal wire connected to the other side of the metal swab The probe card of claim 1, wherein the probe card body is made of glass. The probe card according to claim 2, wherein the probe card body is made of photosensitive glass. The probe card according to claim 1, wherein a metal film is formed on top of the conductive polymer probe.