JP2002040051A - Probe card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe card conformable to a measuring matter chip such as a miniaturized, highly dense and highly integrated present-day LSI chip. SOLUTION: This probe card used for the measurement of electric characteristics of an LSI chip 900 that is the measuring matter comprises a main board 200 having a main conductive pattern 210 formed thereon; a probe 100 having a contact part 110 to make contact with the electrode pad 910 of the LSI chip 900 at the tip and a sharpened connection part 120 at the rear end; a sub-board 300 interposed between the probe 100 and the main board 200 and having a sub-conductive pattern 310 for connecting the probe 100 to the main conductive pattern 210 of the main board 200; and a conductive spring 400 to be fitted to a via hole 320 opened in the sub-board 300 for exposing one end 312 of the sub-conductive pattern 310 and brought into contact with the one end 312. The connection part 120 at the rear end of the probe 100 is connected to the spring 400.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a probe card using a semiconductor integrated circuit such as an LSI as an object to be measured.

[0002]

2. Description of the Related Art Conventional probe cards are roughly divided into:
There are two types, a horizontal type called a cantilever type and a vertical type called a vertical type. This cantilever type has many excellent performances, but in recent years, it has been adapted to the fineness of LSIs, the advancement of high speed, high integration, the simultaneous measurement of multiple devices due to the multiplexing of measuring instruments, etc. Can not.

[0003] For this reason, a vertical type capable of coping with these, as shown in FIG. 4, has been spotlighted. This vertical type probe card includes a substrate 600 which is a multilayer substrate having more than ten layers on which conductive patterns are formed, a probe 610 having a bent portion 613 whose middle portion is bent in a substantially rectangular shape, and Substrate 6
And a probe support 620 having a first guide plate 621 and a second guide plate 622 with the bent portion 613 interposed therebetween. The connection portion 612 at the rear end of the probe 610 is soldered to the conductive pattern 602 on the front surface through a through hole 601 formed in the substrate 600. Further, the first guide plate 621 and the second guide plate 62
2 have through holes 621A and 621A through which the probe 610 passes.
22A are respectively established. The planar arrangement of the probe 610 is designed in accordance with the arrangement of the electrode pads 910 of the LSI chip 900 to be measured.

[0004]

However, the above-described conventional vertical probe card has the following problems. First, in this type of probe card, when the probe 610 is damaged, the bent portion 61 is attached to the probe 610.
3, the first and second guide plates 621,
622A through the through holes 621A and 622A.
Some vertical probe cards are very expensive, using thousands to tens of thousands of probes 610. There is a problem that the probe 610 damaged in this way cannot be pulled out and cannot be replaced.

[0005] As a vertical type probe card which solves such a problem, there is one as shown in FIG. This vertical probe card has a probe 61 curved in an arc shape.
Since 0 is used, only the damaged probe 610 can be pulled out. However, since the connection portion 612 at the rear end of the probe 610 is separate from the conductive pattern 602 of the substrate 600, the probe 610 and the substrate 600 are assembled in a separated form.

Recently, as shown in FIG. 6, a probe card in which a sub-substrate 630 called an interposer is interposed between a probe 610 and a substrate 600 has been developed. If the interposer is used, the substrate 600 and the sub-substrate 630 have the same flatness and dimensions, and therefore the conductive patterns 602 and 63 of the substrates 600 and 630 are used.
1 can be easily connected. However, the flatness of the connection portion 612 at the rear end of the probe 610 may be 200
Since there are irregularities of about μm, it is extremely difficult to connect the connection portions 612 of all the probes 600 and the conductive patterns 631 of the sub-substrate 630.

As shown in FIG. 7, a probe card in which an anisotropic conductive sheet 640 is interposed between a sub-substrate 630 and a connecting portion 612 of a probe 600 has been developed to solve such difficulties. However, due to recent demands for miniaturization and high density, the arrangement of the probes 600 has also been increased, so that it is no longer possible to cope with the isomerically conductive sheet 640. In addition, when the conductive area of the isomerically conductive sheet 640 increases, it becomes difficult to apply a load to the entirety on average. For example, there is a tendency that the pressing force concentrates on the peripheral portion and the pressing force on the central portion becomes insufficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a probe card which can support a measurement object such as a modern LSI chip which is miniaturized, densified, and highly integrated. I have.

[0009]

SUMMARY OF THE INVENTION A probe card according to the present invention is a probe card used for measuring various electrical characteristics of an object to be measured, the probe card being in contact with a main substrate on which a main conductive pattern is formed. The portion contacts the electrode pad of the object to be measured, and the connection portion at the rear end is sharpened, and the probe is interposed between the probe and the main substrate to connect the probe to the main conductive pattern of the main substrate. A sub-substrate having a sub-conductive pattern, and a spring having conductivity provided in the sub-substrate and fitted into a via hole in which one end of the sub-conductive pattern is exposed and in contact with the one end. And a connection portion at a rear end of the probe is connected to the spring.

[0010]

FIG. 1 is a schematic sectional view of a probe card according to an embodiment of the present invention, FIG. 2 is a schematic sectional view of a main part of the probe card according to an embodiment of the present invention, and FIG.
FIG. 2 is a schematic sectional view of a main part of the probe card according to the embodiment of the present invention. Note that the ratio of the dimensions of each part is not correct due to the drawing.

A probe card according to an embodiment of the present invention is a probe card used for measuring various electrical characteristics of an LSI chip 900 to be measured, and includes a main substrate 200 on which a main conductive pattern 210 is formed. And a probe 100 in which a contact portion 110 at the front end contacts the electrode pad 910 of the LSI chip 900 and a connection portion 120 at the rear end is sharpened.
00, the probe 100 and the main substrate 200
Conductive pattern 3 connecting main conductive pattern 210
And a sub-substrate 300 having a sub-pattern 10, and one end 312 of the sub-conductive pattern 310 is fitted into the exposed via hole 320 to be in contact with the one end 312. And a connecting portion 120 at the rear end of the probe 100 is connected to the spring 400.

The main substrate 200 is a multilayer substrate having more than ten layers in which a main conductive pattern 210 is formed over each layer. The lowermost layer of the main substrate 200 has a main conductive pattern 21.
0, and the end 211 of the main conductive pattern 210 is exposed in the uppermost layer.

The sub-substrate 300 has a plurality of via holes 320 on the back side. The via hole 320 is set, for example, to have a diameter of 100 μm and a depth of 1 mm, and a spring 400 described later fits therein. The via hole 320 is set equal to the arrangement of the conductive pads 910 of the LSI chip 900 to be measured.

One end 311 of sub-conductive pattern 310 is exposed on the front side of sub-substrate 300, that is, on the surface facing the lowermost layer of main substrate 200. This one end 3
11 is an exposed end 21 of the main conductive pattern 210
1 is set to be equal to the arrangement.

The other end 312 of the sub-conductive pattern 310 is exposed inside the via hole 320. Therefore, the via holes 320 correspond to the arrangement of the conductive pads 910 of the LSI chip 900 and are densely arranged, but the front end 311 of the sub-conductive pattern 310 is arranged more sparsely. .

The front surface of sub-substrate 300 is in contact with the back surface of main substrate 200, and is provided at end 211 of main conductive pattern 210.
And the end 311 of the sub-conductive pattern 310 corresponding thereto, electrically connecting the conductive pattern 210 and the sub-conductive pattern 310.

A probe support 500 is provided on the back side of the main board 200. The probe support portion 500 includes a hanging member 530 hanging from the back side of the main board 200, and a first guide plate 510 and a second guide plate 5 attached to the hanging member 530 with a certain interval.
20.

First guide plate 510 and second guide plate 520
Are provided with through holes 511 and 521, respectively. The through holes 511 and 521 are provided in the LSI chip 900
Corresponds to the arrangement of the electrode pads 910. Therefore, the through hole 511 of the first guide plate 510 and the corresponding through hole 521 of the second guide plate 520 are located on the same perpendicular line. Further, as shown in FIG. 2 and the like, the probe 100 is fixed by an insulative synthetic resin 540 filled on the upper surface of the first guide plate 510, for example, silicon rubber.

The probe 100 has a contact portion 110 having a sharpened tip, and a connecting portion 12 having a sharpened rear end.
It is 0. The probe 100 is formed, for example, by processing a thin wire of tungsten, and has a diameter of about 90 to 90.
It is 100 μm. The connecting portion 120 of the probe 100 is sharpened by being tapered by 500 μm.

The spring 400 fitted into the via hole 320 has an outer diameter of about 100 μm and an inner diameter of about 50 μm.
m and a length of about 1 mm. Such a spring 40
0 is inserted into the via hole 320 by about 400 μm so that the rest protrudes from the via hole 320.
The spring 400 is made of a conductive material. The spring 400 is connected to the via hole 320
Is electrically connected to one end 312 of the sub-conductive pattern 310 exposed in the via hole 320.

The probe 100 is connected to the connecting portion 12 at the rear end.
0 is inserted into the spring 400 by 500 μm.

That is, the contact portion 110 of the probe 100
From the probe 100 to the end 212 of the main board 200.
Contact portion 110 → connecting portion 120 of probe 100 → spring 400 → one end 312 of sub-conductive pattern 310 → sub-way conductive pattern 310 → one end 311 of sub-conductive pattern 310 →
One end 211 of main conductive pattern 210 → main conductive pattern 3
10 → one end 212 of the main conductive pattern 310.

The probe card thus configured is
The electrical characteristics of the LSI chip 900 are measured as follows.

A plurality of LSI chips 900 in a wafer state are vacuum-adsorbed on the upper surface of a table 950. Table 95
The probe card is lowered toward zero, and the contact portions 110 of all the probes 100 are brought into contact with the electrode pads 910 of the LSI chip 900. Further, the probe card is lowered even after the contact portion 110 contacts the electrode pad 910. Then, the probe 100 is connected to the synthetic resin 540.
Is deformed upward, and the connecting portion 120 at the rear end is securely brought into contact with the spring 400 (see FIG. 3).

Here, the flatness of the main substrate 200 and the sub-substrate 300 is 100 μm or less, and often converges to 50 μm or less. The plane formed by the connecting portions 120 of the many probes 100 is 200 μm, no matter how precisely the probe 100 and the probe supporting portion 500 are assembled.
It is difficult to fit below. Therefore, the probe 10
If the spring 400 is interposed between the contact hole and the sub-conductive pattern 310, the spring
If 0 is interposed in a state of protruding by about 600 μm, the spring 400 can absorb the displacement of the probe 100 in the height direction. In addition, it is possible to absorb a deviation in the planar direction by a difference between the inner diameter of the spring 400 and the diameter of the connection portion 120 of the probe 100.

[0026]

The probe card according to the present invention is a probe card used for measuring electrical characteristics of an object to be measured, wherein a main substrate on which a main conductive pattern is formed and a contact portion at the tip end are to be measured. A probe having a sharpened connection portion at the rear end while being in contact with the electrode pad of the object; and a sub-conductive pattern interposed between the probe and the main substrate and connecting the probe and the main conductive pattern of the main substrate. A sub-substrate having a conductive spring that is opened on the sub-substrate, is fitted into a via hole where one end of the sub-conductive pattern is exposed, and contacts the one end,
A connection portion at the rear end of the probe is connected to the spring.

By the spring interposed between the probe and the sub-substrate, it is possible to secure a reliable conduction while absorbing the displacement in the height direction and the plane direction of the probe. In addition, there is an advantage of using the sub-substrate, that is, exchanging the sub-substrate and the probe support portion, thereby enabling measurement of another type of LSI chip while keeping the expensive main substrate. The cost required for forming the spring and the via hole is less than about 2 yen per probe, so that the cost does not increase significantly.

The connecting portion at the rear end of the probe is sharpened, and the inner diameter of the spring is such that the connecting portion can be inserted, so that the connection between the probe and the spring is more reliable.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a probe card according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a main part of the probe card according to the embodiment of the present invention.

FIG. 3 is a schematic sectional view of a main part of the probe card according to the embodiment of the present invention.

FIG. 4 is a schematic sectional view of a conventional probe card.

FIG. 5 is a schematic sectional view of a main part of a conventional probe card.

FIG. 6 is a schematic sectional view of a main part of a conventional probe card.

FIG. 7 is a schematic sectional view of a main part of a conventional probe card.

[Explanation of symbols]

 100 Probe 200 Main board 300 Sub-board 400 Spring

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroshi Iwata 2-5-13-1 Nishi-Nagasu-cho, Amagasaki-shi, Hyogo Japan Electronic Materials Co., Ltd. F-term (reference) 2G003 AA07 AG03 AG08 AG12 AG19 AH05 2G011 AA02 AA15 AA17 AB01 AB04 AC05 AC14 AD01 AE03 4M106 AA02 BA01 CA01 DD04 DD06 DD10 DD18 DD30

Claims (2)

[Claims] In a probe card used for measuring various electrical characteristics of an object to be measured, a main substrate on which a main conductive pattern is formed and a contact portion at the tip contact an electrode pad of the object to be measured. A probe whose end connection portion is sharpened, a sub-substrate having a sub-conductive pattern interposed between the probe and the main substrate and connecting the probe and the main conductive pattern of the main substrate, And a conductive spring that fits into the via hole where one end of the sub-conductive pattern is exposed, and is in contact with the one end, and the connection part at the rear end of the probe is the spring. A probe card, which is connected to a probe card. 2. The probe card according to claim 1, wherein a connection portion at a rear end of the probe is sharpened, and an inside diameter of the spring is such that the connection portion can be inserted.