JP2000338134A - Probe card and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe card with superior heat-proof stress and the rigidity by adhering and integrating the carbon fiber reinforced-plastic(CFRP) on both surfaces of a core board to reinforce the same. SOLUTION: A disc-shaped metallic or plastic thin plate of approximately 0.5-1.0 mm of thickness is used as a core board 10, and a rectangular through opening 12 for confirming a position is formed on a center of the core board 10. A through-hole 13a for power source ground and a through-hole 13b for needle are formed at both sides of the opening 12, a through-hole 13c for relay and a through-hole 13d for a pogo seat are formed on the outer circumference, and a small hole 14 for mounting or positioning is further formed. The CFRP 20 to be adhered to the front and back surfaces of the core board 10 has approximately 0.2-0.5 mm thickness and the shape same as the core board 10, and is provided with a window hole 22 corresponding to the opening 12 to enable it to be seen through. Window holes 23 are formed corresponding to the through- holes 13a, 13b, and the window holes 23c are formed corresponding to the through-holes 13c, 13d in advance to prevent the electric conduction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe card and a method of manufacturing the same, and more particularly, to an improvement of a probe card used for a tester or a prober for electrically evaluating a device formed on a semiconductor wafer, particularly to an improvement of a core substrate and its improvement. It relates to a manufacturing method.

[0002]

2. Description of the Related Art An outline of a conventionally known tester or prober A will be described with reference to FIG. 1. The prober A includes a wafer chuck 1, a test head 2, and a probe card 3. The wafer chuck 1 holds the semiconductor wafer 4, positions each chip on the wafer, and can move in the horizontal direction and the vertical direction. The test head 2 has a plurality of pin cards 5 built therein. A contact pin 6 attached to the tip is detachably connected to the probe card 3. The probe card 3 is disposed above the wafer 4 and has on its bottom surface a number of probes 7 that are in contact with the electrodes of each chip on the wafer 4. Each probe 7 is formed on the surface and inside of the probe card 3. The connection is made to the contact pins 6 of the pin card 5 through the printed wirings.

[0003]

The above-mentioned probe card 3
Is formed by laminating a wiring substrate for forming the printed wiring on a metal or plastic core substrate in a multilayer shape. In a probe test, inspection is often performed under an extreme temperature environment. For example, in a high-temperature test,
For example, it is placed under a rapid change in the environmental temperature ranging from 5 to 150 ° C., or is placed in a state where there is a temperature difference between the front and back surfaces. Therefore, in the conventional probe card,
There was a problem that the core substrate and the wiring substrate were distorted by thermal stress. In addition, although the number of electrodes has increased in recent semiconductor wafer chips, the probe card 3 has also been required to have a larger number of pins by increasing the number of the probes 7 in response to the increase in the number of electrodes. When connecting the needle 7 to the tip electrode, the contact pressure (load) applied to the probe card 3 increases. However, the core board of the probe card 3 has an upper limit in thickness in order to reduce the weight, and it is difficult to secure a large rigidity. There was also a problem that the core substrate was distorted by the load.

If the probe card 3 is distorted during the test, a misalignment occurs between the set probe 7 and the chip electrode of the semiconductor wafer 4, which causes an inspection error such as poor contact. In particular, in a multi-pin configuration in which the pitch between the electrodes is extremely small, even a slight distortion causes a contact failure, and the reliability of the probe test is significantly reduced. The present invention has been made in view of the above circumstances, and has as its object to provide a probe card which is excellent in heat stress resistance, has high rigidity, and improves reliability of inspection accuracy by reinforcing a core substrate. Another object of the present invention is to provide a manufacturing method capable of manufacturing a robust probe card with good workability.

[0005]

The probe card of the present invention is characterized in that a carbon fiber reinforced plastics layer (CFRP layer) is adhered to both surfaces of a core substrate and integrally formed and reinforced. That is, the present invention is characterized in that a composite material reinforced with fibers having pseudo-isotropic properties is attached to both surfaces of the core substrate to prevent the probe card from being distorted. The above CFRP is a biaxial woven fabric as long as the fibers are arranged to have pseudo-isotropic properties.
It is not limited to the weaving structure such as a triaxial woven fabric and a quadriaxial woven fabric, but preferably, a single-layered triaxial woven fabric having pseudo-isotropic properties satisfies the requirements of the core substrate for light weight and high rigidity. (Claim 2).

Further, according to the manufacturing method of the present invention, at least a predetermined through hole is formed in the core substrate, and an opening including the through hole and a window hole for exposing an expected opening area are opened in the prepreg of CFRP. CF such that the window holes correspond to the opening including the through hole and the expected opening area.
It is characterized in that a prepreg of RP is superimposed on a core substrate and heated and pressed. That is, by opening the window holes in the CFRP in the state of the prepreg, the opening operation is facilitated, and the prepreg is heat-pressed to improve the integration with the core substrate. The core substrate requires a central opening, etc., in addition to drilling a predetermined through-hole in advance, and these openings are drilled in advance in the same manner as the through-hole, or a CFRP prepreg. May be pierced after thermocompression bonding, that is, after the probe card is completed. In the case of the latter method, the portion to be perforated later is set as the planned opening area, and the CFRP is also included including the planned area.
The window hole is opened in the prepreg. On the core substrate, a wiring substrate is laminated in a multilayer shape in order to form a printed wiring. As one of the substrate manufacturing, when a prepreg of CFRP is superimposed on the core substrate, the wiring substrate is placed on the prepreg. Are laminated in a multilayer shape, and they are preferably thermocompression-bonded (claim 4).

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows a main part of a probe card of the present invention. Specifically, a main part of a probe card 3 shown in FIG. 1 is enlarged. FIG. The probe card 3 is a core substrate
Are laminated in multiple layers on one side or both sides of the base 10, and a large number of probes 7 are attached to the lowermost wiring board as described above. In FIG. 2 shows a state in which the wiring substrates are stacked one by one on the upper and lower sides of the core substrate 10 and other wiring substrates and the probe 7 are omitted.

Although a thin metal plate or a thin plastic plate is generally used for the core substrate 10, this embodiment shows a metal core using aluminum. As shown in detail in FIG. 3, the core substrate 10 has a disk shape with a thickness of 0.5 to 1.0 mm for a probe card, a rectangular opening 12 is provided at the center thereof, and Further, a through hole 13 and a small hole 14 for mounting or positioning are formed at predetermined positions on the outer periphery. The central opening 12 is a see-through window for position confirmation at the time of attaching a probe or at the time of a probe test. The through-holes 13 are provided with power supply ground through-holes 13a disposed on both sides of the opening 12, 13b are needle base through-holes, and a plurality of reference numerals 13c disposed on the outer periphery are relay through-holes, 13d. Is a through hole for Pogo seat. CFRP (carbon fiber reinforced plastics) 20 is integrally bonded and reinforced on both front and back surfaces of the core substrate 10.

Since the CFRPs 20 bonded on the front and back sides have the same structure, both will be described using the same reference numerals. CFRP20
Is 0.2 to 0.5 mm thinner than the core substrate 10
And a disk shape having the same shape as the core substrate 10. The CFRP 20 has a window hole 22 at a position corresponding to the opening 12 of the core substrate 10 and a window hole 23a at a position corresponding to the through holes 13a and 13b.
23c and 23d are previously opened at positions corresponding to c and 13d, respectively. The CFRP 20 has a notch 24
Is opened so as to face the small hole 14 of the core substrate 10. The window 22 is provided so as not to block the upper and lower portions of the opening of the core substrate 10 serving as a see-through window.
23a to 23d are to avoid electrical conduction with the conductive material formed in the through hole 13 because the carbon fiber of the CFRP 20 has conductivity.

The CFRP 20 will be described in more detail. The material 20 'of the CFRP 20 is formed by stamping and forming a thin circular plate from a CFRP sheet in a prepreg state (see FIG. 4). Window hole 22,
The CFRP 20 is manufactured by opening the openings 23a, 23c, 23d and the notch 24. The window holes 22, 23a, 23c, 23d and the notch
By opening 24 from the CFRP prepreg, these window holes and the like can be easily processed. The openings of the window holes 22, 23a, 23c, 23d and the notch 24 are C
The blank 20 'may be processed at the same time when the blank 20' is stamped and formed from the FRP sheet. In addition, the carbon fiber 20a of the CFRP 20 is woven into a triaxial (± 60 °) fabric as shown in FIG.

Next, a method of manufacturing the probe card 3 will be described. CFRP 20 in a prepreg state is provided on both the front and back surfaces of the core substrate 10 with the opening 12, the through holes 13a to 13d and the small hole 14 being provided with the window hole. Parts 22, 23a, 23
Polymerization is performed so as to be exposed from c, 23d and the notch 24 (see FIG. 3). Then, on each of the CFRPs 20, a wiring board 11, 11 ′ is interposed via an insulating adhesive layer (prepreg).
Are sequentially laminated in a multilayer shape so as to form a predetermined wiring circuit (see FIG. 2). Thereafter, the core substrate 10, CF
The RP 20 and the wiring boards 11 and 11 'are heated and pressed to adhere to each other to produce a laminated integrated structure.

Instead of this manufacturing process, the core substrate 10 and the front and back CFRP 20 are first heat-pressed to produce a core substrate, and then heat-pressing is performed while forming a circuit for each of the front and back surfaces. Then, a method of laminating the wiring boards may be used. In the above manufacturing process, the core substrate 10
Although the case where the opening 12 was previously drilled was described,
The opening 12 may be opened together with the openings of the wiring boards 11, 11 'after the core substrate 10, the CFRP 20, and the wiring boards 11, 11' have a laminated integrated structure.

[0013]

According to the present invention, both surfaces of the core substrate are CF
Since the substrate and the probe card are reinforced by the RP layer, the rigidity of the substrate and the probe card are increased, and the thermal stress resistance is improved. Therefore, at the time of the probe test, the occurrence of distortion due to the bending and deformation of the probe card can be prevented, and the reliability of the wafer inspection can be improved. In particular, by using a triaxial woven fabric as the carbon fiber, the light weight and high rigidity of the probe card can be ensured, and further reliability can be ensured (claim 2).

Further, according to the manufacturing method of the present invention, since the CFRP which needs to open the window hole is opened in the state of the prepreg, the window hole is easily punched by pressing or the like. It can be removed and has excellent workability,
Since the prepreg is superimposed on the core substrate and heated and pressed, the integrity of the core substrate and the CFRP is ensured, and a high-strength core substrate can be manufactured. According to the fourth aspect, it is possible to manufacture a highly reliable probe card with good workability simply by adding a step of attaching a prepreg to the conventional probe card manufacturing process.

[Brief description of the drawings]

FIG. 1 is a front view showing a schematic configuration of a prober using a probe card of the present invention.

FIG. 2 is an enlarged cross-sectional view of a probe card of the present invention with a part omitted.

FIG. 3 is an exploded perspective view of a core substrate.

FIG. 4 is a perspective view showing a material of CFRP.

FIG. 5 is a sectional view taken along the line (5)-(5) in FIG.

[Explanation of symbols]

3: Probe card 10: Core board
11, 11 ': Wiring board 12: Opening 20: CFRP (carbon fiber reinforced plastics) 13: Through hole 22, 23a, 23c, 23d:
Window hole

Claims (4)

[Claims] 1. A probe card in which a wiring board is laminated in a multilayer shape on a core substrate, wherein a carbon fiber reinforced plastics layer (CFRP layer) is adhered to both surfaces of the core substrate to be integrally formed. card. 2. The probe card according to claim 1, wherein said CFRP is formed using a carbon fiber triaxial woven fabric. 3. A core substrate is provided with at least a predetermined through-hole, and an opening including the through-hole and a window opening for exposing an expected opening area are opened in a prepreg of CFRP. A method of manufacturing a probe card, wherein a prepreg of CFRP is superimposed on a core substrate so as to correspond to an opening portion and an expected opening region including the above, and the resulting substrate is heated and pressed. 4. The method of manufacturing a probe card according to claim 3, wherein a wiring board is laminated in a multilayer shape together with the CFRP prepreg, and they are heated and pressed.