JP3318891B2 - Membrane type probe device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane type probe device used for inspecting a semiconductor device having a plurality of electrodes.

[0002]

2. Description of the Related Art In recent years, the degree of integration in semiconductor devices has increased dramatically, and the number of electrodes taken out of the semiconductor devices has been steadily increasing. Further, wiring and the like of a printed circuit board on which these semiconductor devices are mounted are becoming more complicated.

[0003] For example, this type of semiconductor device is finally sold in the form of being enclosed in a package. Among these semiconductor devices, DIP (Dual Inline Packag)
e), in a semiconductor device having a configuration such as a QFP (Quad Flat Package), leads are drawn out as electrodes on predetermined sides or on each side of each package, and the distance between these leads (ie, , Pitch) becomes 1 mm or less in many cases with an increase in the degree of integration. Here, a case where the leads are arranged so as to cross the side along the side is referred to as a one-dimensional array of electrodes.

Further, a semiconductor device required to have a higher density employs a configuration called a CSP (Chip Size Package). In this case, electrodes taken out from each chip are formed in a ball grid array. , And are two-dimensionally arranged vertically and horizontally. The diameter of the spherical projection used in such a ball grid array is 350 μm-750.
The distance between the balls is about 1 μm or less.

Therefore, wiring according to the electrode configuration of each semiconductor device must be provided also on a mounting substrate such as a printed circuit board on which the above-described semiconductor device is mounted.

On the other hand, these semiconductor devices are inspected before they are shipped to see if they operate normally. At the time of inspection, a method is employed in which a probe is brought into contact with each electrode of a semiconductor device to input an electric signal to each electrode and monitor an output signal with an IC tester.

Among the semiconductor devices described above, DIP, QF
In the semiconductor device having the structure of P, the inspection is performed by contacting an extremely fine needle probe with each lead. However, when the pitch between the leads becomes 200 μm or less, it is very difficult to form the needle probe itself. It becomes difficult. Therefore, it is common practice to extend the lead interval of the portion located outside the package and in contact with the needle probe in accordance with the needle probe used for inspection.

However, as described above, the test in which the needle probe is individually brought into contact with the leads constituting the electrodes has a disadvantage that it takes much time as the number of leads increases. .

In Japanese Patent Publication No. 8-33413,
A test probe using a flexible membrane member (hereinafter referred to as a membrane-type test probe) is disclosed. The disclosed membrane-type test probe is:
The contact pads are formed on the flexible membrane member, and these contact pads are electrically connected to external contact pads via lead wires.

In the membrane-type test probe having this configuration, the flexible membrane member is bent so that the contact pads are brought into contact with the leads on the semiconductor device, and a signal is input / output to each lead to test the semiconductor device. can do. Since this test probe can test a semiconductor device using a large number of contact pads at the wafer stage before packaging, it is economically advantageous as compared with the case of testing after packaging.

[0011]

However, when the leads or pads constituting the electrodes are arranged one-dimensionally in a line on the semiconductor device, the above-mentioned membrane-type test probe has an electrode. The semiconductor device can be tested by contacting the contact pads.

However, in the case of a semiconductor device such as a CSP in which a plurality of ball grid arrays are arranged in a predetermined direction, for a ball array arranged on the outermost periphery of the ball grid array, Although the test can be performed by contacting the contact pads, the contact pads cannot be brought into contact with the ball rows arranged inside the outermost periphery.

An object of the present invention is to provide a membrane-type probe device capable of testing a semiconductor device in which a plurality of rows of electrodes are arranged.

Another object of the present invention is to provide a membrane-type probe device capable of testing a semiconductor device comprising a plurality of semiconductor elements formed on a wafer including a plurality of chips on a wafer-by-wafer basis.

[0015] Still another object of the present invention is to provide a semiconductor device having an electrode spacing of 10
An object of the present invention is to provide a membrane-type probe device capable of performing a test even when the thickness is 0 μm or less.

Another object of the present invention is to provide a membrane-type probe device utilizing a technique for forming fine tungsten spheres.

[0017]

According to the present invention, there is provided a membrane-type probe device used for inspecting a semiconductor device having a configuration in which a plurality of electrodes are arranged, comprising: a membrane member; and an electrode on the semiconductor device. A membrane-type probe device having a conductive spherical projection provided on the membrane member so as to be able to directly contact each other. Here, the conductive spherical protrusion is formed of a ball including a core made of tungsten, and the ball has a size of 60 μm.
m and a diameter variation of +3 μm or less.

Further, in the membrane-type probe device according to the present invention, a pressing element for individually pressing the spherical projections is provided on the membrane member, and each of the pressing elements is provided. Is made of a metal material having elasticity provided in a through hole provided in the membrane member, and the metal material has a surface opposite to the surface of the membrane member on which the spherical projections are arranged. It is connected to the electric wiring formed on the surface.

A membrane-type probe device according to another embodiment of the present invention includes spherical projections arranged on the membrane member so as to be able to directly contact electrodes on a plurality of chips.

The ball used as the above-mentioned spherical projection is selected from a material having at least less electric conductivity (specific resistance) than tungsten, as in the case where tungsten is conventionally used for an inspection probe of a semiconductor device. And is made of tungsten which has a sufficiently higher hardness than copper and has a higher thermal conductivity than 42 alloy, stainless steel or the like. Further, it was also found that the tungsten is less likely to cause pores in a subsequent step.

[0021]

Embodiments of the present invention will be described below.

Referring to FIG. 1, a description will be given of a semiconductor device which can be tested by the membrane type probe device according to the present invention. Although the illustrated semiconductor device is a multi-chip module (MCM) type semiconductor device, it may be a CSP type semiconductor device or a semiconductor device including a plurality of chips formed on a wafer.

The illustrated semiconductor device has a substrate 10 and bump pads 11 arranged in a plurality of rows and columns on one surface of the substrate 10, and these bump pads 11 are provided inside the substrate 10. It operates as an electrode electrically connected to the element. A conductive bump is attached to each bump pad 11. The illustrated bump pad 11 includes a pad row 11A arranged on the outermost periphery, and pad rows 11B and 11C arranged on the inner side of the substrate 10 from the outermost pad row 11A. Note that the interval (ie, pitch) between the pads is 0.7-0.8 mm.

As shown, the bump pads 11
Are connected to a conventional membrane-type test probe (for example, Japanese Patent Publication No. 8-3341).
It is very difficult to test with the test probe described in Japanese Patent Publication No. This is because when the test probe described in the publication is used, the contact pads of the test probe can be brought into contact with the pad row 11A arranged on the outermost periphery in FIG. This is because the contact pads cannot be brought into contact with the pad rows 11B and 11C.

Taking this into consideration, the membrane type probe device 20 according to the present invention has a contact pad portion at the center as shown in FIG. 2 and takes into consideration the connection with the IC tester. And has a circular outer shape. A contact pad 21 having the same arrangement as the arrangement of the bump pads of the semiconductor device is provided in advance in the center contact pad portion. More specifically, the illustrated contact pads 21 of the membrane type probe device 20 include a contact pad row 21A corresponding to the outermost peripheral pad row 11A shown in FIG. 1 and a pad row 11B arranged inside. , 11C are arranged corresponding to the contact pad rows 21B, 21C, respectively.
The number and pitch of 1C are the pad rows 11A and 11
B, 11C. In this case, if each contact pad constituting the contact pad row can contact a corresponding pad on the substrate 10, the size of each contact pad will be larger than that of the corresponding substrate 1.
It may be slightly different from the size of the pad above zero.

The contact pads 21 provided on the contact pads of the membrane type probe device 20 are formed on a transparent resin, for example, polyimide or the like.
1 is electrically connected to tester connection electrodes 22 arranged on the outer periphery of the membrane type probe device 20 via electric wiring 23 (broken line).

Referring to FIG. 3, there is shown a positional relationship between the membrane type probe device 20 shown in FIG. 2 and the substrate 10 shown in FIG. As shown in FIG. 3, bump pads 11 are arranged on a substrate 10 of a semiconductor device, while a
The contact pads 21 arranged in the center of the substrate 10 are arranged one-to-one with the bump pads 11 on the substrate 10. The illustrated contact pad 21 is constituted by spherical projections 25 having a tungsten core, and each spherical projection 25 is provided on the transparent membrane member 2 of the membrane type probe device 20.
6 (for example, polyimide), the membrane-type probe device 20
Can be brought into contact with the bump pads 11 of the corresponding substrate 10.

Specifically, the illustrated spherical projection 25
Is a through hole 27 formed in the membrane member 26.
Through the electrical wiring 2 on the other surface of the membrane member 26
3 is electrically connected.

Here, as shown in FIG.
5 comprises a spherical tungsten core 36, a base plating layer 37 provided thereon, and a solder coating layer 38 provided on the surface. The illustrated tungsten core 36 had a diameter D1 of 60 μm, and its diameter accuracy was ± 2 μm or less. It has been confirmed that a tungsten core having a diameter of about 80 μm can be used, and a diameter accuracy of ± 3 μm or less can be used practically. Further, the base plating layer 37
It is formed of a nickel layer having a thickness of 0.1-0.3 μm, and the solder coating layer 38 has a thickness of 7-8 μm.
Is formed by a PbSn layer having a thickness of Thus, the overall diameter D2 of the illustrated spherical projection 25
Was 75 μm. The solder coating layer 38 is made of AgS
n, CuSn or the like. The method of manufacturing these spherical projections 25 was described in detail in Japanese Patent Application No. 10-62782 filed by the present inventors.
I won't explain again.

Returning to FIG. 3, the membrane member 20 includes
A through hole 27 having a diameter of about 70 μm is provided corresponding to each spherical projection 25, that is, each bump pad 11. In each through hole 27, a spherical projection 25 is formed in the bump pad 11 of the substrate 10. A wire rod 30 of a metal material having elasticity is inserted as a pressing element for pressing down. The wire 30 is formed of, for example, a gold-plated wire of maraging steel, beryllium copper alloy, or the like, or a conductive wire having a spring property is formed in a ribbon shape, and one end of the wire 30 is spherical. Protrusion 25
It is fixed to.

According to experiments by the present inventors, as a method of fixing the wire 30 to the minute spherical protrusion 25, a laser pulse of 0.4 Joule is applied for 2 milliseconds and the spherical protrusion 25 and the wire 30 are fixed.
It was confirmed that laser welding could be performed by irradiating the tip of the sample. Also, the wire 30 in the through hole 27
May be in the form of a ribbon. In this case, the wire 30 in the form of a wire or a ribbon is subjected to one or a few minute embossings in order to exert a spring function in the length direction in advance, and when a compressive force is applied, the wire 30 is stretchable and stretchable. Exercise function can be provided. Therefore, at the time of contact, complete continuity is obtained with respect to the bump pad 11 side, and unnecessary extra torque can be avoided and absorbed to prevent damage to the electrode portion.

When the wire 30 is formed in a ribbon shape, one (30 in the figure) or two
Since it can be inserted and attached by more than the book (30 '), it is also effective for adjustment and reinforcement of the minute spring portion.

The other end of the wire 30 included in the through hole 27 is connected to a metal material for forming the electric wiring 23, for example, copper by a brazing material or the like. Therefore,
Each spherical projection 25 is connected to a tester connection electrode 22 shown in FIG. 2 via a wire 25 and an electric wiring 23.

When a semiconductor device is tested using the membrane type probe device 20 shown in FIG. 3, the membrane type probe device 20 is mounted on the bump pad 11 of the substrate 10 of the semiconductor device as shown in FIG. It is positioned in.
At this time, the membrane-type probe device 20 is positioned such that the spherical projections 25 are one-to-one with the bump pads 11 on the substrate 10. In order to facilitate this alignment, it is desirable that the membrane member 26 be formed of a transparent material.

Here, the surface of the substrate 11 of the semiconductor device is
Usually, the projections and depressions have a roughness of about 2 μm, so that the distance between the surface of the substrate 11 and the spherical projection 25 is kept at about 6 μm. In this state, the clamp member 31 made of silicone or the like is used for the electric wiring 23 of the membrane member 26.
And the membrane member 26 is pressed by the clamp member 31. Due to this pressing, the wire 30 in the through hole 27 connected to the electric wiring 23 becomes 1
Each of the spherical protrusions 25 extends downward by about 0 μm in FIG.
1 was fully in contact. Further, according to the experiment, the wire 30 could be configured to be able to extend up to 20 μm.

As described above, the bump pads 1 on the substrate 11
1 and the spherical projection 25 are in contact with each other, and the IC tester is connected to the tester connection electrode 22, the semiconductor device becomes
Can be tested by a tester.

The illustrated membrane probe device 20
Since the spherical projection 25 operating as a probe of the above is spherical, the contact with the bump pad 11 of the substrate 11 is as close as possible to a point and the tip is not sharp, so that the contact between the spherical projection 25 and the bump pad 11 There is an advantage that the bump pad 11 is not damaged by the contact.

In the above-described embodiment, the membrane-type probe device for testing the multi-chip module has been described. However, the present invention is not limited to this. The present invention can be applied to various semiconductor devices by changing the arrangement of the pads 21 according to the pads of the semiconductor device to be tested or the electrode arrangement. Therefore, the semiconductor device to be tested is FC
/ BGA (Flip Chip Ball Grid Array), Ball Grid Array (BGA), FC-C
For testing such as SP (flip chip-chip size package) etc., the membrane type probe device according to the present invention
Can be used.

Further, in the embodiment shown in FIG. 3, the case where the membrane member 26 is a single layer has been described, but if a material having heat resistance and flexibility is used, the membrane member 2 can be used.
It is also possible to make 6 a multilayer structure, in which case
It is also possible to test a semiconductor device having more electrodes, for example, an entire wafer, with a single membrane probe device.

As a spherical projection used in the present invention, a tungsten core having a diameter of 80 μm or less, preferably 60 μm or less and having an isotropic structure has been developed. However, a membrane-type probe device for testing semiconductor devices arranged at intervals of 100 μm or less can also be manufactured.

Further, as a pressing element for pressing the spherical projection, not only an elastic wire, but also an electrostrictive element or the like can be used.

[0042]

As described above, according to the present invention,
According to the electrodes of the semiconductor device to be tested, conductive spherical protrusions are arranged on the membrane member, and the spherical protrusions are directly contacted with the electrodes of the semiconductor device, and a membrane-type probe device for performing a test is used. can get. Therefore, the probe device according to the present invention has an advantage that a semiconductor device having a complicated electrode arrangement can be easily tested. Furthermore, since the spherical projection is used as the contact probe, even if it comes into contact with the electrode of the semiconductor device to be tested, there is an effect that the electrode is not damaged. Further, since the spherical projections themselves can be extremely miniaturized, even if the pitch or interval of the electrodes of the semiconductor device becomes extremely narrow, each spherical projection can be individually contacted with each electrode one by one. Further, the membrane-type probe device according to the present invention,
Since the quality of the semiconductor device can be determined before the semiconductor device is sealed in the package, the cost required for the package can be reduced. In the state of the semiconductor wafer,
Since it is possible to determine pass / fail for each chip, it is possible to omit processing for a defective chip.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a semiconductor device that can be tested by a membrane-type probe device according to one embodiment of the present invention.

FIG. 2 is a plan view illustrating a membrane-type probe device according to one embodiment of the present invention.

FIG. 3 is a partial cross-sectional view showing a positional relationship between a membrane-type probe device according to an embodiment of the present invention and a semiconductor device to be tested.

FIG. 4 is a cross-sectional view for explaining a configuration of a spherical projection used in the membrane-type probe device according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Substrate of semiconductor device 11, 11A, 11B, 11C Bump pad 20 Membrane type probe device 21, 21A, 21B, 21C Contact pad 22 Tester connection electrode 25 Spherical protrusion 26 Membrane member 27 Through hole 30 Wire 31 Clamp member 36 Tungsten core 37 Base plating layer 38 Solder coating layer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiko Mizukami 2nd Iwase Koshi-cho, Toyama-shi, Toyama Pref. Toyama Works, Tokyo Tungsten Co., Ltd. (72) Inventor Yoshihiko Doi 5-24-8 Higashi-Ueno, Taito-ku, Tokyo Tokyo Tungsten Co., Ltd. (56) References JP-A-7-211753 (JP, A) JP-A-7-20150 (JP, A) JP-A-4-330749 (JP, A) JP-A-7-288271 (JP, A) JP-A-8-304462 (JP, A) JP-A-9-101326 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 1/06-1 / 073 G01R 31/26 H01L 21/66

Claims (8)

(57) [Claims] In a membrane type probe device used for inspecting a semiconductor device having a configuration in which a plurality of electrodes are arranged, a membrane member and an electrode on the semiconductor device can be directly contacted with each other. A conductive spherical projection provided on the membrane member, and a pressing element provided on the membrane member and coupled to the spherical projection, for individually pressing the spherical projection, The element is made of a metal material having elasticity provided in a through hole provided in the membrane member, and the metal material is on a side opposite to a surface of the membrane member on which the spherical protrusions are arranged. A membrane-type probe device, which is connected to electric wiring formed on the surface of the probe. 2. The membrane-type probe device according to claim 1, wherein said electric wiring is connected to a tester connection electrode arranged around said membrane member. 3. The membrane-type probe device according to claim 1, wherein the conductive spherical projection is formed by a ball including a core made of tungsten. 4. The claim 1, wherein the ball has a feature that it is formed by a tungsten core having a diameter of less than 80 [mu] m, and and have a diameter of less than accuracy ± 2 [mu] m Membrane-type probe device. 5. The one of claims 1 to 4, wherein the semiconductor device is constituted by a plurality of chips formed on the wafer, the electrode on the plurality of chips,
The membrane-type probe device, wherein the spherical protrusions are arranged on the membrane member so as to be able to make direct contact. In any one of claims 6] claims 1 to 5, wherein the arrangement of the spherical projections, the arrangement of the electrodes on the semiconductor device, a membrane type probe device which is a same. 7. The membrane-type probe device according to claim 1, wherein the spherical projections are arranged in a plurality of rows in a predetermined direction on a surface of the membrane member. 8. The method of claim 7, wherein the spherical projection are also a direction that intersects the predetermined direction, the membrane type probe device characterized by being a plurality of rows arranged.