JP2000155131A - Contact probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent contact pins from having deformation variation at overdriving. SOLUTION: This probe 1 is constituted by forming pattern wires 3 on the surface of a film body 2 and projecting the tips of the pattern wires from the tip part of the film body as contact pins 3a. Here, a belt-like film 4 is provided, which supports the contact pins 3a by connecting them with one another at their intermediate parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact probe which is used as a probe pin, a socket pin, or the like, and performs an electrical test by contacting each terminal of a semiconductor IC chip, a liquid crystal device, etc. For inspecting ICs on the wafer of the surface-arranged terminals.

[0002]

2. Description of the Related Art Generally, a probe card is used to perform an electrical test by contacting a semiconductor chip such as an IC chip or an LSI chip or each terminal of an LCD (liquid crystal display).

[0003] As this type of probe card, the one shown in Fig. 10 has been conventionally known. That is, in this probe card, an opening is provided at a measurement position of the card on the glass epoxy plate, and a contact pin (needle) is provided at this position.
Are provided in a protruding form. As a material of the needle, a tungsten (W) material having a small degree of wear is generally used. The probe card shown in this figure has a cantilever shape in which contact pins extend obliquely downward, and is called a horizontal needle type.

As shown in FIG. 9, as terminals to be inspected by a probe card, there are peripherally arranged terminals having terminal electrodes formed only around the chip, and terminal electrodes formed over the entire surface of the chip. And surface-arranged terminals. Here, the horizontal needle type probe card can cope with the peripherally arranged terminals, but cannot cope with the surface arranged terminals, and there is a limit in increasing the number of pins. Further, the horizontal needle probe card has a limit in the height of the measurement frequency because the total length of the contact pins is as long as about 40 to 30 mm.

Therefore, instead of the horizontal arrangement type, FIG.
The vertical arrangement type shown in FIG. According to this vertical needle type probe card, it is possible to cope with surface-arranged terminals and to realize a multi-pin configuration. In addition, the length of the contact pins is relatively short, about 11 to 7.5 mm. Be improved.

[0006] However, the vertical arrangement type has the following problems. For needles that use high rigidity such as parinai, a curved part is provided in the middle of the needle and these needles are positioned by a holder with holes in ceramics etc. Due to limitations on the needle diameter, pitches below 100 μm cannot be accommodated.

On the other hand, for example, Japanese Patent Publication No. 7-82
No. 027 proposes a contact probe technique in which a plurality of pattern wirings are formed on a resin film, and the tips of the pattern wirings are arranged so as to protrude from the resin film and serve as contact pins. In this technology example, by using the contact pins at the tips of a plurality of pattern wirings, it is possible to arrange a plurality of contact pins with high precision, to achieve a narrower pitch of multiple pins and to eliminate the need for a large number of complicated components. It is assumed that.

A conventional contact probe 100 is shown in FIG.
As shown in FIG. 2, the IC probe is cut into a predetermined shape as an IC probe, and has a structure in which a pattern wiring 103 made of Ni (nickel) or a Ni alloy is adhered to the surface of a polyimide resin film 102. The end of the pattern wiring 103 protrudes from the end of the film 102 to form a contact pin 103a.

In recent years, it has been proposed to incorporate this contact probe into a vertical needle type probe card. That is, with the recent high integration, the electrode pitch of LSIs and the like is also becoming narrower, and in order to cope with this, the contact pins of the above-mentioned contact probes are vertically arranged, and the two-dimensional needle arrangement is performed at a narrower pitch. Is what makes it possible.

Meanwhile, the surface of each electrode terminal (pad) of an IC chip or the like formed of an Al (aluminum) alloy or the like is oxidized in the air and is covered with a thin aluminum surface oxide film. ing. Therefore, in order to conduct an electrical test of the pad, the surface oxide film of aluminum on the surface is peeled off and the aluminum inside is exposed,
It is necessary to ensure conductivity.

Therefore, by applying overdrive while making the contact pin contact the surface of the pad,
The tip of the contact pin must scrape off the aluminum oxide film on the pad surface to expose the aluminum inside. The work described above is a scrub
This is called (scrub) and is important in ensuring electrical testing.

[0012]

The above-mentioned conventional probe technology has the following problems. That is, when the overdrive is applied, the vertically arranged contact pins may be bent and deformed in a direction different from the predetermined scrub direction, and an accurate needle position may not be obtained. That is, even if the contact pins are bent in a predetermined scrub direction to have directionality, there is an inconvenience that the contact pins bend in a lateral direction with respect to the predetermined scrub direction.

The present invention has been made in view of the above-mentioned problems, and has as its object to provide a contact probe capable of preventing variation in deformation of contact pins during overdrive.

[0014]

The present invention has the following features to attain the object mentioned above. That is, in the contact probe according to the first aspect, a plurality of pattern wirings are formed on the surface of the film main body, and the respective tips of the pattern wirings are arranged so as to protrude from the front end of the film main body and become contact pins. In this case, a technique is employed in which a belt-shaped guide film is provided to connect and support the contact pins at their intermediate portions.

In this contact probe, a strip-shaped guide film is provided to support the respective contact pins by connecting them to each other at an intermediate portion thereof, so that the adjacent contact pins are connected to each other to provide a predetermined scrub. Direction (for example, contact pin arrangement direction)
This deformation is suppressed even if it is attempted to bend separately in different directions (lateral directions).

In the contact probe according to the second aspect,
2. The contact probe according to claim 1, wherein each of the contact pins employs a technique in which a curved portion is formed between the guide film and the film main body.

In this contact probe, since a curved portion is formed between the guide film of each contact pin and the film main body, the contact pin is divided into a curved portion and a tip portion on the tip side of the guide film. It is possible to bend in two parts, and it becomes possible to control the bending in two steps with respect to the load.

In the contact probe according to the third aspect,
The contact probe according to claim 1 or 2,
The guide film employs a technique in which a metal film is directly attached.

In this contact probe, even if the guide film is, for example, a resin film or the like that easily expands by absorbing moisture, a metal film is directly attached to the film, so that the metal film is Thereby, elongation of the guide film is suppressed. In other words, the distance between the contact pins is less likely to be shifted, and the tip portion is accurately and accurately contacted with the object to be measured.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a contact probe according to the present invention will be described below with reference to FIGS. In these figures, reference numeral 1 denotes a contact probe, 2 denotes a resin film main body (film main body), 3 denotes pattern wiring, and 4 denotes a guide film.

As shown in FIG. 1, the contact probe 1 of this embodiment has a structure in which a pattern wiring 3 made of metal is attached to one surface of a polyimide resin film main body 2. The distal end of the pattern wiring 3 protrudes from the distal end to form a contact pin 3a. Each of the contact pins 3a is provided with a guide film 4 which is a belt-like polyimide resin film and supports the contact pins 3a by connecting them at an intermediate portion thereof.

Further, the contact pin 3a has a distal portion 3b on the distal side from the guide film 4 formed of a curved portion provided on the proximal side and a beam portion extending tangentially from the curved portion. The beam portion of the tip 3b is formed obliquely at a predetermined angle in the scrub direction.

Since the distal end portion 3b has the above-described shape, the stress at the time of overdrive is transmitted to the curved portion via the beam portion, absorbed and reduced by the entire curved portion, and the stress on the pattern wiring is reduced. A beam portion having an oblique axis is easily pushed out in the axial direction, and is likely to skid. That is, stress concentration during overdrive does not occur, and the beams can slide sideways. The guide film 4 has a width, a connecting position, and the like set so that the spring property of the contact pin 3a is not impaired.

As shown in FIGS. 2 to 4, the probe device 70 (the surrounding printed circuit board is not shown) moves the contact probe 1 against a contact surface Pa of a terminal electrode (measurement object) P. A plurality of the resin films 2 are arranged so as to be substantially vertical, and are juxtaposed between the respective surfaces of the resin film 2 via a spacer 2e. The spacer 2 e is made of, for example, a non-conductive material such as ceramics, and also functions as a support for supporting the contact probe 1. A positioning hole 2h is provided in a side portion of the resin film main body 2, and the contact probe 1 is positioned by inserting a ceramic rod 2j into the positioning hole.

As shown in FIG. 3, on the back surface of the resin film main body 2 where the pattern wiring 3 is formed,
A metal film 500 is provided. Similarly,
The guide film 4 is also provided with a strip-shaped metal film 500 on the surface opposite to the contact pins 3a.

FIG. 4 is a diagram showing a contact probe 1 cut out into a predetermined shape as an IC probe.
FIG. 5 is a cross-sectional view along the pattern wiring 3 of the contact probe 1. As shown in FIG. 4, the resin film main body 2 is provided with a positioning hole 2h for inserting the rod 2j. As shown in FIGS. 4 and 6, the pattern wiring 3 is connected to one end of a flexible substrate (FPC) 9 via a lead wiring 10, and the other end of the flexible substrate 9 is connected to a printed circuit board 20. Thus, the probe device 70 is configured.

The probe device 70 configured as described above
When performing a probe test or the like of an IC chip having surface-arranged terminals by using the probe device 70, the probe device 70 is mounted on a prober and electrically connected to a tester. In this state, the contact pins 3a of the contact probe 1 are connected to the terminals. The contact surface Pa of the electrode (measurement object) P is brought into contact by overdrive. Further, by sending a predetermined electric signal from the contact pin 3a of the pattern wiring 3 to the IC chip on the wafer, an output signal from the IC chip is transmitted from the contact pin 3a to the tester, and the electric characteristics of the IC chip are measured. Is done.

At the time of the above measurement, since the contact probe 1 is provided with the belt-like guide film 4 for connecting and supporting the respective contact pins 3a at their intermediate portions, a predetermined scrub direction (that is, the contact pins 3a) is provided. Of the adjacent contact pins 3 even if they attempt to bend in the lateral direction with respect to the
a is connected to each other via the guide film 4, deformation in the lateral direction is suppressed.

Further, even if the guide film 4 is a polyimide resin film PI which easily absorbs moisture and stretches, since the guide film 4 is provided with the metal film 500 directly attached thereto, The film 500 suppresses the elongation of the guide film 4.
That is, the gap t between the contact pins 3a is less likely to be shifted, and the tip 3b is accurately and accurately contacted with the terminal of the IC chip to be measured.

Preferably, the metal film 500 is not easily deformed by heat and moisture.
Any of Ni alloy, Cu and Cu alloy is suitable.

Next, referring to FIG. 7, the steps of manufacturing the contact probe 1 will be described in the order of the steps.

[Base Metal Layer Forming Step] First, as shown in FIG. 7A, a base metal layer 6 is formed on a stainless supporting metal plate 5 by Cu (copper) plating.

[Plating Step] (Pattern Forming Step) After a photoresist layer (mask) 7 is formed on the base metal layer 6, FIG.
As shown in FIG.
Then, a photomask 8 having a predetermined pattern is applied to the substrate, and the photoresist layer 7 is exposed, and as shown in FIG. Opening (unmasked part)
7a is formed.

At this time, the shape of the portion corresponding to the contact pin 3a in the opening 7a is formed by bending the distal end side so that the curved distal end 3b is formed as shown in FIG. Keep it.

In the present embodiment, the photoresist layer 7 is formed of a negative photoresist, but a desired opening 7a is formed by employing a positive photoresist.
May be formed. Further, the means for forming the opening 7a is not limited to the one in which the opening 7a is formed through the exposure and development steps using the photomask 8 like the photoresist layer 7 of the present embodiment. For example, a film or the like in which a hole is formed in advance in a portion to be plated (that is, the film is formed in advance in a state indicated by reference numeral 7 in FIG. 7C) may be used. When such a film or the like is used as a mask, the pattern forming step in the present embodiment is unnecessary.

(Electroplating Step) Then, FIG.
As shown in FIG. 7, after the Ni or Ni alloy layer N to be the pattern wiring 3 is formed in the opening 7a by plating, the photoresist layer 7 is formed as shown in FIG.
Is removed.

[Film Adhering Step] Next, FIG.
As shown in FIG. 2, the resin film main body 2 is bonded to the Ni or Ni alloy layer N with an adhesive 2a except for the tip portion of the pattern wiring 3 shown in FIG. Glue. Further, the belt-shaped guide film 4 is bonded with an adhesive 2a so that the intermediate portion of the contact pin 3a, that is, the base end portion of the portion to be the front end portion 3b is connected to each other.

The resin film body 2 and the guide film 4 are made of a metal film (copper foil) 50 made of polyimide resin PI.
Reference numeral 0 denotes a two-layer tape provided integrally. In particular, in the resin film main body 2, before the film attaching step, the copper surface 500 of the two-layer tape is subjected to copper etching using a photoengraving technique to form a ground surface.
In this film attaching step, the resin surface PI of the two-layer tape is bonded to the Ni or Ni by the adhesive 2a.
It is deposited on the alloy layer N. In addition, the metal film 500
In addition to the copper foil, Ni, Ni alloy or the like may be used.

Further, a method may be adopted in which the guide film 4 is separated from the resin film main body 2 after being applied by using a film in which the resin film main body 2 and the guide film 4 are integrated. For example, a film in which the resin film main body 2 and the guide film 4 are integrally formed is applied via a connecting portion formed only of the polyimide resin, and after the film attaching step, a connecting portion without a metal film is applied by a laser beam or the like. May be burned off to separate the guide film 4 from the resin film main body 2. In this case, by performing copper etching using a photoengraving technique in advance to form a connecting portion of only the polyimide resin, it is possible to accurately and easily separate the two. As described above, in the method of selectively forming the portion to be the guide film 4 by the photolithography technique, a highly accurate guide film 4 can be formed.

It should be noted that Au is previously placed on the metal film 500.
Although a plating layer (not shown) is applied to protect the substrate from Cu etching in a separation step described later, the connecting portion between the resin film main body 2 and the guide film 4 is covered with a tape or the like and is not Au-plated. This portion of the metal film 500 may be removed together with the base metal layer 6 by etching, and only the polyimide resin may be used.

[Separation Step] Next, as shown in FIG. 7 (g), the portion composed of the resin film main body 2, the guide film 4, the pattern wiring 3 and the base metal layer 6 is separated from the supporting metal plate 5. After that, only the pattern wiring 3 is adhered to the resin film main body 2 via Cu etching. By this separating step, the contact pins 3a are formed so as to protrude from the resin film main body 2, and the respective contact pins 3a are connected to the guide film 4 at an intermediate portion thereof.

[Gold Coating Step] Then, as shown in FIG.
Plating is applied to form an Au layer AU on the surface. At this time, the Au layer AU is formed on the entire surface of the contact pin 3a protruding from the resin film main body 2 over the entire periphery of the tip 3b. Thereafter, the contact probe 1 is cut into a predetermined shape as an IC probe.

In the method of manufacturing the contact probe 1, in the plating process, the portion corresponding to the contact pin 3a is formed by using the photolithography technique. Contact pins 3a can be formed simultaneously and with high precision.

That is, since the mask exposure technique is used,
With respect to the tip 3b of the contact pin 3a, the curvature of the curve, the pin width, and the like can be accurately adjusted, and as a result, the direction and amount of bending can be accurately controlled. Moreover, once the photomask 8 is manufactured,
Since it can be used repeatedly, it is possible to mass-produce a higher-precision product, for example, as compared with a method in which a contact pin is bent using a jig or the like after the production of the contact pin.
Further, the tip 3b can be easily formed not in the shape of the curved portion and the beam portion but in another shape, for example, a shape bent obliquely and linearly at a predetermined angle.

Next, a second embodiment of the contact probe according to the present invention will be described with reference to FIG.

The second embodiment is different from the first embodiment in that the contact pin 3a of the first embodiment has a straight line between the guide film 4 and the resin film body 2, whereas the contact pin 3a of the first embodiment has a straight line. Contact probe 3 of 2 embodiment
In the contact pin 32a of FIG. 1, the curved portion 3 has a predetermined curvature between the guide film 4 and the resin film main body 2.
2c is formed.

That is, the curved portion 32 is provided between the guide film 4 of each contact pin 32a and the resin film main body 2.
c, the contact pin 32a is connected to the distal end portion 32b on the distal end side of the guide film 4 and the curved portion 32.
c can be bent at the two divided portions, and the bending can be controlled in two steps with respect to the load. For example,
When the load during overdrive is up to 3g, the tip 32b
Only when the load exceeds 3 g, the bending portion 32c can be set to be further bent.

In order to manufacture the contact probe 31, for example, in the above-described plating process, the curved portion 32 is formed on the photoresist layer 7 by photolithography.
A photomask having a pattern having a curved portion is applied to a portion corresponding to c. After the exposure / development process, an opening 7a having the curved portion is formed in the photoresist layer 7, and a Ni or Ni alloy layer N is formed in the opening 7a by plating. A pin 32a is obtained.

In each of the above embodiments, the contact probe 1 is used for the probe card. However, the contact probe 1 may be used for another measuring jig or the like. For example, the present invention may be applied to an IC chip test socket or the like mounted on an IC chip burn-in test device or the like for holding and protecting the IC chip inside.

[0050]

According to the present invention, the following effects can be obtained. (1) According to the contact probe of the first aspect, since the belt-shaped guide film for connecting and supporting each contact pin at an intermediate portion thereof is provided, the contact pins are different from each other due to the connection by the guide film. The deformation in the direction can be suppressed, and the movement of the needle position due to the variation in deformation can be prevented.

(2) According to the contact probe of the second aspect, since the curved portion is formed between the guide film of each contact pin and the film main body, the contact pin is formed by the tip portion and the curved portion. It is possible to bend in steps, and various deflection controls can be set for the load.

(3) According to the contact probe of the third aspect, even if the guide film is a resin film or the like which easily expands by absorbing moisture, a metal film is provided directly on the film. Therefore, the elongation of the guide film is suppressed by the metal film, the gap between the contact pins is less likely to occur, and the contact pins can be accurately and accurately contacted with the object to be measured.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of an essential part showing a probe device in a first embodiment of the contact probe according to the present invention.

FIG. 3 is a cross-sectional view along a pattern wiring showing a probe device in a first embodiment of the contact probe according to the present invention.

FIG. 4 is a plan view showing a first embodiment of the contact probe according to the present invention.

FIG. 5 is a cross-sectional view taken along the pattern wiring of the contact probe in FIG.

FIG. 6A is a plan view showing a probe device according to a first embodiment of the contact probe according to the present invention,
(B) is the same side view.

FIG. 7 is a fragmentary cross-sectional view showing a method of manufacturing the contact probe according to the first embodiment of the present invention in the order of steps.

FIG. 8 is an enlarged plan view of a main part showing a second embodiment of the contact probe according to the present invention.

9A and 9B show types of arrangement of electrode terminals, wherein FIG. 9A shows peripheral arrangement terminals, and FIG. 9B shows surface arrangement terminals.

FIG. 10 is a side view showing a horizontal needle type probe card.

FIG. 11 is a side view showing a vertical needle type probe card.

FIG. 12 is a perspective view of a main part showing a conventional example of a contact probe according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 31 Contact probe 2 Resin film main body (film main body) 3 Pattern wiring 3a, 32a Contact pin 3b, 32b Tip part 4 Guide film 32c Curved part 70 Probe device 500 Metal film

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideaki Yoshida 12th Techno Park, Mita-shi, Hyogo F-term (reference) 2M011 AA16 AA17 AB01 AB07 AC06 AE03 AE22 AF06 4M106 AD01 AD11 AD26 BA01 DD03 DD09 DD13

Claims (3)

[Claims] 1. A contact probe in which a plurality of pattern wirings are formed on a surface of a film main body, and each end of the pattern wirings is arranged so as to protrude from the front end of the film main body and is used as a contact pin. A contact probe, comprising a belt-shaped guide film for connecting and supporting the contact pins at an intermediate portion thereof. 2. The contact probe according to claim 1, wherein each of said contact pins has a curved portion formed between said guide film and said film main body. 3. The contact probe according to claim 1, wherein a metal film is directly attached to the guide film.