JPH0381669A - Probe for probe card - Google Patents

Abstract

PURPOSE:To put the probe in stable contact with an electrode pad even if the probe wears by forming a drum part which has the same or approximate section from nearby a bent part, formed at a halfway part of a stylus main body to the tip of the stylus. CONSTITUTION:The stylus main body 2 is formed while tapered toward the tip side at a constant angle and provided with the bent part 14 at its halfway part and has the drum part 16 formed from nearby the bent part 14 to the stylus tip 8, and the stylus main body 2 and drum part 16 are formed integrally of an electrode material such as tungsten. The drum part 16 is formed of a columnar body which has the same section as the stylus tip 8 or approximate section through a curved surface 18 which is formed slightly arcuately the part on the side of the stylus tip 8 slightly from the bent part 14. The angle of the bent part 14 corresponds to the direction angle of the stylus main body 2 to a semiconductor device 4 to be measured, the drum part 16 is perpendicular to the surface of the electrode pad 6, and the stylus tip 8 forms a parallel plane with the electrode pad 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a probe for a probe card used to measure the electrical characteristics of a semiconductor device in the process of being manufactured.

[Conventional technology]

Conventionally, as shown in FIG. 6, in probe cards for probe cards, a needle body 2 is formed of an electrode material made of tungsten or the like and has a conical shape that tapers at a certain angle on the tip side. The needle tip 8 is bent toward the electrode pad 6 of the semiconductor device 4.

In the semiconductor device 4, a large number of functional elements 12 such as transistors and resistors are formed on a semiconductor substrate 1i10 whose negative side is several millimeters, and terminals are formed to connect the internal circuit and external circuit. Therefore, a large number of fine electrode pads 6 are formed.

So, with the probe card! ! In order to measure the electrical characteristics of the semiconductor device 4 under manufacture and determine whether it is good or bad, a large number of probes are provided to contact each electrode pad 6 at the same time. The tip 8 of each probe is set to have the same shape in order to maintain constant measurement accuracy.

[Problems to be Solved by the Invention] By the way, making the tip diameter of a certain conical probe the same makes the adjustment work complicated, which affects the product price.

In addition, since the needle tip 8 is in mechanical contact with the electrode pad 6, even if it is made of a hard electrode material, it will wear out, and with a probe that is supposed to have a conical shape, the tip diameter will gradually decrease due to the tip abrasion. As a result, the area of contact with the electrode pads 6 varies, and there are disadvantages such as partial contact failure.

-i, according to the standard for the probe used for the 100 μm electrode pad 6, the needle tip 8 needs to fit within a range of 70 μm inside the electrode pad 6. The needle tip 8 is set to have a diameter of about 50 μm, but if the amount of slippage of the needle tip 8 during contact with the electrode pad 6 is 15 μm, the effective occupied area of the needle tip 8 on the electrode pad 6 is 65 μm. .

However, as the density of semiconductor devices 4 has increased, the − side has become 80
If a small electrode pad 6 of μm or 60 μm is used, it is difficult for a conventional probe to meet the standards, and if the diameter of the needle tip 8 increases due to wear, the needle tip 8 will come off from the electrode pad 6, resulting in poor contact. wake up

Conventionally, for example, according to JP-A-52-115187 "Measuring needle for probe card", a three-dimensional curved probe as shown in FIG. 7 has been proposed. Although it has advantages such as uniform bending stress, large amount of deflection, and uniform contact pressure to the electrode pad, it is not suitable for small electrode pads 6 because the needle tip 8 tends to enlarge due to wear. .

Accordingly, the first object of the present invention is to provide a probe for a probe card, in which the tip of the probe maintains its initial state even when worn, and a stable contact state can be obtained even with small electrode pads.

A second object of the present invention is to provide a probe for a probe card in which the mechanical strength of the body is increased when the body has a cross-sectional shape that is the same as or similar to the tip of the needle.

[Means to solve the problem]

(Claim 1) That is, in order to achieve the above object, the probe card probe of the present invention is brought into contact with the electrode pad (6) of the semiconductor device (4) to be measured.
A body part (16) is formed from the middle part of the needle body (2) to the needle tip (8) side and has a cross section that is the same as or similar to the needle tip surface, and the needle tip is formed by bending the middle part of the needle body. A bent portion (14) facing the electrode pad is provided.

(Claim 2) Furthermore, in order to achieve the second object, the probe for a probe card of the present invention is such that the body portion is held perpendicularly to the electrode pad using the bent portion.

(Claim 3) Furthermore, in order to achieve the second object, the probe for a probe card of the present invention includes a large diameter portion ( 16a) and a small diameter portion (16b) having a cross section that is the same as or similar to the needle tip.

[Function] (Claim 1) In the probe for a probe card of the present invention, the body formed between the vicinity of the bent part formed in the middle part of the needle body and the tip of the needle has the same or similar cross section. Therefore, even if the needle tip is formed at any location on the body, the same needle tip can be obtained.

Therefore, if the bodies of a plurality of probes are made cylindrical, for example, and set to have the same diameter, the needle tip diameters will inevitably be set to the same diameter, making it easier to set the needle tip diameters. In manufacturing, it is easy to set the body part as a cylinder with the same diameter, so setting the needle tip diameter is easier than in the conventional case.

In such a probe, the cross-sectional shape of the body is the same as or similar to the shape of the tip of the needle, so the tip of the needle is
Even after wear, the same or similar shape is obtained by the body, so the initial state is maintained and stable contact with the electrode pad is maintained.

(Claim 2) The needle body is formed to have a sufficient thickness to maintain needle pressure, and the body has a cross-sectional shape that is the same or similar to the needle tip corresponding to the electrode pad of the semiconductor device to be measured. is formed. Therefore, the body is thinner than the needle main body, and its mechanical strength is lower than that of the needle main body.

Therefore, in the probe for a probe card of the present invention, a bent portion is formed on the needle body side, and the bent portion is used to set the body portion perpendicularly to the electrode pad. In this way, when the electrode pad is contacted, the direction of the stress on the body coincides with the axial direction of the body, and no horizontal stress is applied to the body. As a result, the body is protected from bending, breaking, etc., and a stable state of contact with the electrode pad can be maintained for a long period of time.

(Claim 3) Furthermore, the mechanical strength of the body is increased by forming the body with a large-diameter portion and a small-diameter portion having a cross section that is the same as or similar to that of the needle tip.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIGS. 1 and 2 show an embodiment of a probe for a probe card according to the present invention.

The needle body 2 is formed thinner at a certain angle toward the tip side, and a bent part 14 is provided in the middle of this needle body 2, and a body part 16 is formed between the vicinity of this bent part 14 and the needle tip 8. is,
The needle body 2 and the body 16 are integrally formed of an electrode material such as tungsten.

The needle body 2 is formed into a conical shape with a thickness that is sufficient to withstand stress in order to obtain sufficiently high mechanical strength and needle pressure of the probe, and whose tip end tapers at a certain angle.

Further, the body portion 16 is a columnar body having a cross-sectional shape that is the same as or similar to the shape of the needle tip 8 through a curved surface 18 formed with a gentle arc from a portion slightly on the needle tip 8 side from the bent portion 14. It is formed.

For example, if the needle tip surface is made circular, the body 16 will be
It is formed into a columnar body with a circular cross section of the same or similar size. In other words, the needle tip 8 is formed by the end surface of the body portion 16 and, like the surface of the electrode base 6, is in a horizontal plane.

The angle of the bent portion 14 is determined according to the angle at which the needle body 2 is directed toward the semiconductor device 4 to be measured, so that the body portion 16 is perpendicular to the surface of the electrode pad 6, and the needle tip 8 is set perpendicular to the surface of the electrode pad 6.
It is set so that parallel planes are affected.

Although not shown, the rear end side of the needle body 2 is fixed to a probe card and electrically connected to a measuring device.

With the above configuration, since the body portion 16 is formed to have the same diameter as the needle tip 8, the body portion 16 having the same diameter is formed by machining or the like.
It is possible to easily produce multiple probes with The length of the body 16 can be adjusted by arbitrarily cutting the body 16, and any probe corresponding to the semiconductor device 4 can be easily manufactured.

In this way, in a probe in which the body 16 is formed with a cross-sectional shape that is the same as or similar to that of the needle tip 8, even if the needle tip 8 wears out, it is possible to maintain the same shape of the needle tip 8. be able to.

Since the body part 16 is held perpendicular to the electrode pad 6 by setting the angle of the bent part 14, the contact stress coincides with the axial direction of the body part 16 when contacting the electrode pad 6. Therefore, the body portion 16 is protected from damage such as bending or other deformation due to horizontal stress, or breakage, and can maintain a stable contact state with the electrode pad 6 over a long period of time.

Next, FIGS. 3 to 5 show other embodiments of the probe for a probe card according to the present invention.

In the embodiment described above, the body portion 16 is formed from the vicinity of the bent portion 14 via the curved surface 18, but as shown in FIG. The body 16 having the same diameter as the needle tip 8 may be formed by forming the stepped portion 20 parallel to the surface of the needle tip 8, and the same effect as in the embodiment described above can be obtained.

Further, as shown in FIG. 4, the bent portion 14 side of the body portion 16 formed with the stepped portion 20 is made into a large diameter portion 16a, and the large diameter portion 16a is provided with a stepped portion 22 to form the needle tip 8. A small diameter portion 16b having the same diameter may be provided. In this way, the small diameter portion 16b, which has the same diameter as the needle tip 8, can be set to the minimum necessary length, so that the mechanical strength of the body portion 16 can be increased.

In addition, as shown in FIG. 5, the large diameter portion 16 shown in FIG.
The large-diameter portion 16a may be formed into a conical portion 24, except for the step portions 20.22 at both ends of a.

In the embodiment, the body 16 has a cross-sectional shape that is the same as or similar to the needle tip 8, but for example, the wear length of the needle tip 8 is set to 1.
When the diameter is 00 μm, the shape of the needle tip 8 may have a gentle conical shape to the extent that the change in shape is within an allowable range.

〔Effect of the invention〕

As explained above, according to the present invention, the following effects can be obtained.

(a) There is no need to adjust the needle tip, which reduces manufacturing costs.Furthermore, even if it wears out, the needle tip is formed by the body, so the initial state can be maintained, and the electrode A stable state of contact with the putt can be maintained.

(b) Since the body is held vertically, the body can be protected from deformation such as bending and damage such as breakage, and stable contact with the electrode pad can be maintained for a long period of time. I can do it.

(C) Since the body is provided with a large diameter portion, the mechanical strength of the body is increased, deformation such as bending, damage such as breakage can be prevented, and the state of contact with the electrode pad can be stabilized.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the probe card probe of the present invention, FIG. 2 is a vertical sectional view of the probe card probe and semiconductor device shown in FIG. 1, and FIGS. 3 to 5 The figure is a longitudinal sectional view showing another embodiment of the probe for a probe card according to the present invention, and FIGS. 6 and 7 are perspective views showing the conventional probe for a probe card. 2... Needle body 4... Semiconductor device 6... Electrode pad 8... Needle tip 14... Bent part 16... Body part 16a... Large diameter part 16b... Small diameter Part diagram diagram

Claims (1)

[Claims] 1. In a probe for a probe card that is brought into contact with an electrode pad of a semiconductor device to be measured, the probe is formed from the middle part of the needle body to the needle tip side and has a cross section that is the same as or similar to the needle tip surface. A probe for a probe card, comprising: a body portion; and a bent portion that bends a midway portion of the needle body to direct the tip of the needle toward the electrode pad. 2. The probe for a probe card according to claim 1, wherein the body is held vertically by the electrode pad at the bent portion. 3. The body portion is characterized by comprising a large-diameter portion that is continuous with the bent portion on the needle body side and a small-diameter portion that has a cross section that is the same as or similar to the needle tip. The probe for a probe card according to claim 1 or 2.