JP2000055936A - Contactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contactor which has a high degree of freedom in the arrangement of its probe terminals, is capable of arranging the probe terminals according to any electrode arrangement of a body to be inspected and further simultaneously inspecting a plurality of elements formed in a body to be inspected, is seldom thermally affected at the time of inspection, is superior in contacting/property, performs accurate and reliable contact, and is capable of performing highly accurate inspection. SOLUTION: This contactor 1 is simultaneously brought into contact with 16 or 32 pieces of chips and performs electric inspection on a wafer a few times. The contactor 1 is provided with a plurality of first electrodes 3 arranged on the surface of a silicon substrate 2 and probe terminals 4 each provided for the electrodes 3. The probe terminal 4 comprises a conductive supporting column 7 erected on the first electrode 3, a cantilever spring 8 conduction-freely cantilevered and supported at the upper end of the conductive supporting column 7, a bump 9 supported at the free end part of the cantilever spring 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contactor used for inspecting electrical characteristics of a device under test.

[0002]

2. Description of the Related Art An object to be inspected, such as a semiconductor wafer (hereinafter, referred to as a semiconductor wafer)
Simply referred to as "wafer". When an electrical characteristic test is performed on an IC chip such as a memory circuit or a logic circuit formed in a large number of times, a probe card is used as a contactor. The probe card plays a role of relaying the transmission and reception of the test signal between the tester and the IC chip when the probe card comes into contact with the electrode pad of the wafer during the test. This probe card has, for example, a plurality of probe needles corresponding to a plurality of electrode pads formed on an IC chip, and inspects the IC chip by electrically contacting each probe needle with each electrode pad. Like that.

In recent years, the integration degree of IC chips has increased, and the number of electrode pads has rapidly increased, and the pitch of the electrode pads has been increasingly narrowed. Along with this, the number of probe needles of the probe card has rapidly increased, and the pitch has been narrowed. In addition, the number of IC chips in the wafer increases rapidly with the increase in the diameter of the wafer, and a long time is required for inspection, and shortening the inspection time has become an important issue. Therefore,
When testing with a probe card, instead of testing each IC chip one by one,
The number of chips (same number) is increased to shorten the inspection time.

[0004]

However, in the conventional probe card, since a plurality of probe needles are individually supported in a cantilever manner, when the electrode pads are arranged in a plurality of rows, the support structure of the probe needles becomes extremely large. Become complicated,
It is difficult to change the arrangement of the probe needles according to the various arrangements of the electrode pads, and the degree of freedom of the arrangement of the probe needles is low.
In addition, there is a problem that the tip position of the probe needle is likely to be out of order due to the thermal influence at the time of inspection.

The present invention has been made to solve the above-mentioned problems, and has a high degree of freedom in the arrangement of probe terminals, and can arrange probe terminals in accordance with an arbitrary electrode arrangement of a device under test. Moreover, a contactor capable of simultaneously inspecting a plurality of elements formed on an object to be inspected, being less susceptible to thermal effects during the inspection, having excellent contact properties, and being capable of performing accurate and reliable contact and performing a highly accurate inspection. It is intended to provide.

[0006]

According to a first aspect of the present invention, there is provided a contactor comprising a plurality of first electrodes arranged in a central region of one surface of a substrate, and probe terminals provided on these electrodes, respectively. And a plurality of second electrodes arranged in a peripheral region of the other surface of the substrate corresponding to the probe terminals and the first electrodes, and electrically connecting the second electrodes and the wiring substrate on the tester side. An elastic connection member to be connected, a contactor performing an electrical characteristic test of the device under test by contacting a plurality of elements formed on the device under test a plurality of times, wherein the probe terminal is a It has a conductive support member erected on one electrode, an elastic support plate supported at the upper end of the conductive support member in a cantilever manner so as to be conductive, and a bump supported at a free end of the elastic support plate. It is characterized by .

A contactor according to a second aspect of the present invention includes a plurality of first electrodes arranged in a central region on one surface of a substrate, a probe terminal provided on each of these electrodes, A plurality of second arrays arranged in a peripheral region of the other surface of the substrate corresponding to the probe terminals and the first electrodes
An electrode, and an elastic connecting member for electrically connecting the second electrode to the wiring board on the tester side. A contactor for inspecting an electrical characteristic of a body, wherein the probe terminal includes a conductive support member erected on a first electrode, and a tip end approaching each other at an upper end of the conductive support member so as to be conductive. It has a pair of elastic support plates held and supported, and a pair of bumps supported at the free end of each elastic support plate.

The contactor according to a third aspect of the present invention is the contactor according to the first or second aspect,
A locking member is provided for restricting the free end of the elastic support plate from approaching the substrate.

A contactor according to a fourth aspect of the present invention includes a plurality of first electrodes arranged in a central region on one surface of a substrate, probe terminals provided on these electrodes, and A plurality of second arrays arranged in a peripheral region of the other surface of the substrate corresponding to the probe terminals and the first electrodes
An electrode, and an elastic connecting member for electrically connecting the second electrode to the wiring board on the tester side. A contactor for inspecting electrical characteristics of a body, wherein the probe terminal comprises: a conductive support member erected on a first electrode; a conductive annular plate supported on an upper end of the conductive support member; It has a conductive annular plate and a bump formed integrally and supported at the center of the elastic erection part.

Hereinafter, the present invention will be described with reference to the embodiments shown in FIGS. As shown in FIGS. 1 and 2, for example, the contactor 1 according to the present embodiment has a plurality of rectangular first electrodes arranged in a matrix on the surface of a silicon substrate 2 and made of a conductive metal such as nickel or a nickel alloy. 3 and
A plurality of probe terminals 4 respectively disposed on these electrodes 3, each probe terminal 4 including an inspection electrode pad (not shown) made of a conductive metal such as aluminum or copper formed on a wafer; Contact, for example, a plurality (eg, 16
Or 32 IC chips can be inspected simultaneously. The silicon substrate 2 is formed in a circular shape as shown in FIGS. The central region 2A having a square shape on the surface of the silicon substrate 1 is shown in FIG.
The probe terminals 4 are arranged in a matrix as shown in FIG. 2A, and the peripheral region 2B on the back surface thereof has a second electrode electrically connected to the first electrode 3 as shown in FIG. The electrodes 5 are arranged in a circular shape. The first electrode 3 and the second electrode 5 are electrically connected to each other via wires 6 made of the same kind of metal as the electrodes 3 and 5 formed in the silicon substrate 2 as shown in FIGS. Connected.

Here, the probe terminal 4 will be described in more detail. As shown in FIG. 1 and FIG. 2, the probe terminal 4 includes a pair of conductive support columns 7 having the same height and erected at opposing corners of the first electrode 3, respectively. 7. An elastic support plate (hereinafter, referred to as a "cantilever spring") 8, which is cantilevered at the upper end so as to be able to conduct horizontally horizontally, and is conductively supported at a free end of the cantilever spring 8 And the bump 9 formed.
The plane shape of the cantilever spring 9 is not limited to the U-shape, but may be a U-shape. That is, the cantilever spring 8 is connected to the upper ends of the pair of conductive support columns 7 at the base ends of two sides facing each other, and the free end of the other side is close to the adjacent cantilever spring 8. A bump 9 is fixed to the center of the free end of the cantilever spring 8. As shown in FIGS. 1 and 2, the bump 9 has a columnar portion 9A which is a support portion formed in a substantially columnar shape, and the columnar portion 9A.
A and a truncated quadrangular pyramid 9B, which is a contact portion connected to and integrated with the upper surface of A. And, for example, the cantilever spring 8 is formed of a conductive metal having a spring force and toughness such as nickel or a nickel-cobalt alloy.
Therefore, when the bump 9 comes in contact with the electrode pad of the wafer, the bump 9 is pressed against the electrode pad by the spring force of the cantilever spring 8 so as to achieve conduction between the bump 9 and the electrode pad and absorb the height difference between the electrode pads. It is. Further, the bump 9 has, for example, a cylindrical portion 9 </ b> A made of the same conductive metal as the cantilever spring 8, and a truncated square pyramid portion 9.
B is formed of a material having a higher hardness than the electrode pads of the wafer, for example, a conductive metal such as tungsten carbide. Then, for example, gold,
It is coated with a highly conductive metal such as rhodium or an alloy thereof.

As shown in FIGS. 1 and 2, a locking member 12 is provided below the bumps 9 on the surface of the silicon substrate 2 so that each bump 9 comes into contact with an electrode pad of the wafer. The free ends of the cantilever springs 8 are locked by the locking members 12 as shown by the dashed lines in FIG. 2 so that the bumps 9 are not pushed in more than necessary, so that the cantilever springs 8 are prevented from being damaged. is there. For example, the locking member 12 is formed in a fence shape as shown in FIG.
, The free ends of the plurality of cantilever springs 8 arranged in a row are simultaneously locked. This locking member 12 may be formed as a pillar-shaped locking member adjacent to each first electrode 3 instead of the fence shape.

As shown in FIG. 2, a printed wiring board 11 such as a performance board is connected to the back surface of the silicon substrate 2 via a ribbon-shaped elastic connecting member 10 made of, for example, a gold alloy. The contactor 1 is connected to a tester (not shown) via the cable 11. The ribbon-shaped elastic connection member 10 has a bent surface 10A as shown in the figure, and the bent surface 10A is connected to the second electrode 5 arranged in the peripheral region 2B on the back surface of the silicon substrate 2, and the other end is printed. Electrode 11 of wiring board 11
A is connected. The surface of the elastic connecting member 10 is formed of a conductive metal film having a spring force and a toughness, such as nickel or a nickel-cobalt alloy, so that it can be automatically connected to the second electrode 5 by a ribbon-compatible bonding device. It is.

Next, a method for manufacturing the contactor 1 of the present embodiment using the LIGA (Lithographie, Galvanoformung, Abformung) process will be described with reference to FIGS. 5 and 6, for example. First, as shown in FIG. 5A, after a silicon oxide film 21A is formed on the surface of the silicon substrate 21, a resist film 22 is formed on the surface. Next, after exposing through a photomask 23 conforming to the pattern of the bumps 9, the resist film 22 is subjected to development processing, and a rectangular hole 22A is formed in the resist film 22 as shown in FIG. Subsequently, after removing the silicon oxide film 21A in the portion of the hole 22A, the silicon substrate 21 is subjected to anisotropic etching, and as shown in FIG. The resist film 22 and the silicon oxide film 21A are removed. Further, as shown in FIG.
An oxide film 24 is formed on the surface of the substrate, and a titanium film 25 is formed on the surface.
To form Then, a resist is applied, and the resist film corresponding to the hole 21B is removed by exposure and development to open the hole 21B. Then, a tungsten carbide-cobalt alloy is sputtered, and as shown in FIG. The hole 21B of the silicon substrate 21 is filled with a tungsten carbide-cobalt alloy to form a portion corresponding to the truncated pyramid portion (contact portion) 9B of the bump 9 of the probe terminal 4.
The silicon oxide film 24 serves as a separation layer when separating the truncated pyramid portion 9B of the bump 9 from the hole 21B of the silicon substrate 21, and the titanium film 25 prevents metal diffusion of the tungsten carbide-cobalt alloy forming the truncated pyramid portion 9B. Barrier layer.

Thereafter, as shown in FIG. 6A, a highly transparent resist containing polymethyl methacrylate (PMMA) is applied to form a sacrificial layer 26, which is exposed and developed. Then, a circular or square hole 26A is formed in the corresponding portion of the truncated pyramid portion 9B of the bump 9 by performing the processing.
To form By using PMMA having high transparency, light rays such as X travel straight through the sacrifice layer 26 and pass through to form holes 26A having a high aspect ratio. Next, as shown in FIG. 6B, the holes 26 are formed by electroforming, for example, with a nickel alloy.
A is filled, and a columnar portion 9A of the bump 9 is formed. Next, a separation layer of a titanium film is formed on the surface of the sacrifice layer 26 and the surface of the cylindrical portion 9A made of a nickel alloy as shown in FIG. 6B, and a resist film is further formed on the surface thereof. Then, the corresponding portion of the cylindrical portion 9A made of a nickel alloy is opened, and the titanium film in the portion is removed by etching to make the nickel alloy of the cylindrical portion 9A solid. Further, after applying a resist containing PMMA to the surface thereof to form a sacrificial layer 27, a predetermined pattern is opened by exposure and development to form a concave portion corresponding to a cantilever spring in the sacrificial layer 27, and FIG. As shown in (1), the concave portion is filled with a nickel alloy by electroforming to form the cantilever spring 8, and the cantilever spring 8 and the cylindrical portion 9A are integrated. 6C, the sacrificial layer 28 made of the same resin as the sacrificial layer 26, its cylindrical hole 28A, and the fence-shaped groove 28 corresponding to the locking member 12. Next, as shown in FIG.
B are respectively formed. Then, the sacrificial layer 28 is masked leaving the fence-shaped grooves 28B, and the fence-shaped grooves 28B are filled with, for example, polysilicon to form the locking members 12, and then the nickel alloy is filled in the cylindrical holes 28A by electroforming. 6D, the conductive support pillars 7 are formed, and as a result, the probe terminals 4 and the locking members 12 can be formed in the sacrificial layers 26, 27, 28 on the surface of the silicon substrate 21. Next, the silicon substrate 21 is joined to the silicon substrate 2 for the contactor, the conductive support pillar 7 is connected to the first electrode 3 of the silicon substrate 2 and the locking member 12 is
The two silicon substrates 2 and 21 are integrated in a state adjacent to the electrode 3. Next, the probe terminal 4 is treated with hydrofluoric acid or the like.
From the sacrificial layers 26, 27, 28.

Further, the elastic connection member 10 is connected to the second electrode 5 of the silicon substrate 2 using a bonding device, and at the same time, for example, wax or the like is applied as a sacrifice layer to this surface, and the elastic connection member 10 is embedded in the sacrifice layer. . Next, the surface of the sacrifice layer is polished, the free ends of the elastic connection members 10 are aligned at the same height, and then joined to the printed wiring board 11, and the free ends of the elastic connection members 10 are connected to the electrodes 11A of the printed wiring board 11. Then, the printed wiring board 11 is integrated with the silicon substrate 2, and as a result, the silicon substrate 2 and the printed wiring board 11 are integrated. After that, when the wax is removed, the contactor 1 connected to the printed wiring board 11 is produced.

Next, the operation of the contactor 1 when the contactor 1 is mounted on a probe device will be described. For example, as shown in FIG.
The wafer W is placed on the mounting table 30 movable in the Y, Z and θ directions.
After the mounting, the mounting table 30 is moved to a position directly below the contactor 1, and the positioning of each probe terminal 4 and each electrode pad of the wafer is performed using a positioning mechanism. Next, when the mounting table 30 is raised, 16 or 3 wafers formed on the wafer W are formed.
The electrode pads of the two IC chips contact all the probe terminals 4 of the contactor 1 at a time. Further, when the mounting table 30 is overdriven, a stylus pressure acts on the probe terminal 4. At this time, even if there is a height difference between the electrode pads of the wafer W, the cantilever spring 8 is elastically deformed according to the height of each electrode pad to absorb the height difference, and the bumps 9 of the probe terminals 4 are absorbed. Is surely cut into each electrode pad by the spring force of the cantilever spring 8 and makes electrical contact with the electrode pad, and conducts between the tester and each IC chip.
Inspect the IC chip. At this time, as shown by a dashed line in FIG.
Of the cantilever spring 8 is prevented from being excessively deformed toward the silicon substrate 2 side. Thereafter, the mounting table 30 is lowered, moved in the X direction or the Y direction, and index-feeds the wafer, and the next 16 or 32 ICs are mounted.
Inspect the chip. Further, in the present embodiment, since the contactor 1 and the printed wiring board 11 such as a performance board are connected by the elastic connection member 10, the height difference of the electrode pads of the wafer can be absorbed by the elastic connection member 10. In addition, a force for pushing the bump 9 into the electrode pad can be applied. Further, if the probe device equipped with the contactor 1 of the present embodiment is incorporated into a semiconductor manufacturing process and is inlined, defective products can be screened at an early stage of the process.

As described above, according to the present embodiment,
The probe terminals 4 are electrically conductive support columns 7 erected on the first electrodes 3 formed on the entire surface of the silicon substrate 2.
And a cantilever spring 8 that is cantilevered at the upper end of the conductive support column 7 so as to be conductive, and a bump 9 that is supported by the cantilever spring 8, so that the pitch of the electrode pads on the wafer is reduced, and the IC chip Even if the arrangement of the electrode pads is arranged in a plurality of rows, the probe terminals 4 can be freely arranged corresponding to the arrangement of the electrode pads, and even if heat is generated during the inspection, the thermal influence of the probe terminals 4 can be reduced. There is no displacement between all the probe terminals 4 and the electrode pads without any displacement, and accurate and reliable contact is achieved. In addition, the cantilever spring 8 absorbs the difference in the height of the electrode pads caused by the warpage of the wafer and provides good contact characteristics. And a high-precision inspection can be performed. Further, since the contactor 1 of the present embodiment is connected to the printed wiring board 11 such as a performance board via the elastic connecting member 10, even if the wafer has a warp or the like, the warp is absorbed through the elastic connecting member 10. In addition, the contact property of the contactor 1 can be further improved. Also, cantilever spring 8
Of the cantilever spring 8 can be prevented from being excessively deformed and prevented from being damaged, and the operation of attaching the probe terminal 4 to the silicon substrate 2 can be automated. be able to.

Next, another embodiment of the present invention will be described with reference to FIGS. The contactors shown in FIGS. 7 and 8 are basically configured according to the above embodiment except that the probe terminals are different, and therefore the same or corresponding parts as those in the above embodiment are denoted by the same reference numerals. I do. The probe terminal 4 shown in FIG. 7 is supported by a pair of conductive support columns 7 erected at diagonal corners on the first electrode 3 having a square shape, and the upper end of the conductive support column 7. A support plate 8 having a square frame shape;
And a bump 9 supported at the center of a bridge portion 8A integrally formed on the diagonal line of the bridge. As shown in the figure, the bump 9 is formed in a columnar shape having a flat surface at the tip. In the case of the probe terminal 4, since all the ends are not sharp as in the case of the above-described embodiment, the probe terminal 4 can be suitably used when inspecting a wafer having a solder bump formed on an electrode pad. That is, since the tip of the bump 9 is a flat surface, the probe terminal 4 comes into contact with the solder bump, and even if overdrive is applied, the bump 9 of the probe terminal 4 does not bite into the solder bump, and The IC chip can be inspected by making electrical contact, and the height difference of the solder bumps can be absorbed by the elastic deformation of the erection portion 8A, and the same operation and effect as in the above embodiment can be expected. it can. Therefore, since the bumps 9 are pressed vertically against the solder bumps, the solder bumps can be returned to the original form without dust or the like entering the solder bumps during reflow after inspection, and each IC chip can be flip-chip mounted. Can be provided as a KGD.

The probe terminal 4 shown in FIG. 8 is used for an aluminum pad. This probe terminal 4 is composed of a pair of cantilever spring portions 8B cut at the center of the bridging portion 8A of the support plate 8 shown in FIG. , 8B, and a small gap is formed between the respective tips. Then, split bumps 9A, 9A having two rectangular or columnar bumps 9 in the vertical direction at the free ends of the pair of cantilever spring portions 8B, 8B.
Has been fixed. In the case of the probe terminal 4, when the probe terminal 4 comes into contact with the aluminum pad, the split bumps 9A, 9A are pushed toward the second electrode 3 against the spring force of the cantilever spring portions 8B, 8B, and the split bumps 9A are pressed. , 9A are in contact with the aluminum pad as one bump by the contact of the divided surfaces, and the same inspection as the contactor shown in FIG. 7 can be performed, and the same operation and effect can be expected. .

In the above embodiment, the case where the probe terminal 4 is manufactured based on nickel is described, but a noble metal such as palladium may be used. In the above embodiment, titanium is used as the separation layer, but silver or the like can be used instead of titanium. The bumps shown in FIGS. 7 and 8 may be formed as bumps having truncated pyramids shown in FIGS.
May be protected by an insulating film, and the shape and arrangement of the probe terminals are not limited to the above embodiment, and may be any shapes and arrangements utilizing the elasticity of the cantilever spring 8. . Alternatively, the bumps themselves may be directly provided on a substrate such as a silicon substrate as probe terminals.

[0022]

According to the first to fourth aspects of the present invention, the degree of freedom in the arrangement of the probe terminals is high, and the probe terminals are arranged in accordance with an arbitrary electrode arrangement of the device under test. It is possible to inspect a plurality of elements formed on the device under test at the same time. Can be provided.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view showing a main part of a contactor according to an embodiment of the present invention.

FIG. 2 is a side view showing the contactor shown in FIG.

FIG. 3 is a plan view showing the entire surface of the contactor shown in FIG. 1;

FIG. 4 is a plan view showing the entire back surface of the contactor shown in FIG. 1;

5 (a) to 5 (d) are views showing steps for manufacturing a bump portion of the probe terminal shown in FIG.

6 (a) to 6 (d) are views showing steps of manufacturing a portion other than the bump portion of the probe terminal shown in FIG.

FIGS. 7A and 7B are diagrams showing a main part of another embodiment of the contactor of the present invention, wherein FIG. 7A is a plan view and FIG. 7B is a side view of FIG.

FIG. 8 is a view showing a main part of still another embodiment of the contactor of the present invention, wherein (a) is a plan view thereof, and (b) is a side view of (a).

[Explanation of symbols]

 Reference Signs List 1 contactor 2 silicon substrate 3 first electrode 4 probe terminal 5 second electrode 7 conductive support column 8 cantilever spring, elastic support plate 8A erection portion 8B cantilever spring portion 9 bump 9A cylindrical portion (support portion) 9B square pyramid portion ( Contact part) 10 elastic connecting member 12 locking member

Continued on the front page F-term (reference) 2G011 AA16 AA21 AB01 AB06 AB08 AC14 AE03 AF01 4M106 AA01 AA02 BA01 BA14 DD03 DD04 DD09 DD10 DD16 DJ32

Claims (4)

[Claims] 1. A plurality of first electrodes arranged in a central region of one surface of a substrate, probe terminals respectively provided on these electrodes, and the substrate corresponding to the probe terminals and the first electrodes. A plurality of second electrodes arranged in a peripheral region of the other surface of the first surface, and an elastic connection member for electrically connecting the second electrodes to a wiring board on the tester side, and formed on the device under test. A contactor for performing an electrical characteristic test on the device under test by contacting a plurality of elements in a plurality of times, wherein the probe terminal comprises: a conductive support member erected on a first electrode; A contactor comprising: an elastic support plate supported at the upper end of a flexible support member in a cantilever manner so as to be conductive; and a bump supported by a free end of the elastic support plate. 2. A plurality of first electrodes arranged in a central region on one surface of a substrate, probe terminals provided on these electrodes, and the substrate corresponding to the probe terminals and the first electrodes. A plurality of second electrodes arranged in a peripheral region of the other surface of the first surface, and an elastic connection member for electrically connecting the second electrodes to a wiring board on the tester side, and formed on the device under test. A contactor for performing an electrical characteristic test on the device under test by contacting a plurality of elements in a plurality of times, wherein the probe terminal comprises: a conductive support member erected on a first electrode; A contactor comprising: a pair of elastic support plates supported at the upper ends of the elastic support members with their ends close to each other so as to be freely conductive and cantilevered; and a pair of bumps supported at the free ends of the respective elastic support plates. . 3. The contactor according to claim 1, further comprising a locking member for restricting the free end of the elastic support plate from approaching the substrate. 4. A plurality of first electrodes arranged in a central region on one surface of the substrate, probe terminals provided on these electrodes, and the substrate corresponding to the probe terminals and the first electrodes. A plurality of second electrodes arranged in a peripheral region of the other surface of the first surface, and an elastic connection member for electrically connecting the second electrodes to a wiring board on the tester side, and formed on the device under test. A contactor for performing an electrical characteristic test on the device under test by contacting a plurality of elements in a plurality of times, wherein the probe terminal comprises: a conductive support member erected on a first electrode; A contactor comprising: a conductive annular plate supported at an upper end of a flexible support member; and a bump supported at the center of an elastic erection portion formed integrally with the conductive annular plate.