JPH08304456A - Conductive rod-like single crystalline worked body and assembly for measuring electric characteristic using the body - Google Patents

Abstract

PURPOSE: To achieve positionally accurate connection and sufficient conduction with a body to be tested and measure with high accuracy and high density, by setting a diameter and a length of rod-like single crystal body and a thickness of a coating conductive film, etc., within a specific range. CONSTITUTION: A rod-like single crystal body is formed so that a ratio (aspect ratio) of a length l and a diameter (d) becomes 1-500. Side faces of the body 1 are coated with a conductive film 2 of a thickness of 0.1-10μm. A relationship of a distance L(μm) between a fixed face and a front end of a worked body 3 of the conductive rod-like single crystal and the diameter (d) (μm) is set to hold 10<=L<=3000, 0.1<=d<=600, d<-2.4> .L<3.8> >=5.0×10<4> . More preferably, the diameter (d) is 1-50μm, the length l is 200μm-5mm and the thickness of the conductive film 2 is not larger than d×0.4μm and not smaller than 0.1μm, and at the same time, at least a surface of the conductive film is formed of Pd. A surface of the worked body 3 is coated with an insulating film 4 of a thickness of 0.1-10μm except a front end part thereof. As a result, the worked body 3 and an assembly for measuring electric characteristics are formed accurately with high density.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe pin for measuring electric characteristics of a semiconductor integrated circuit, a micro vacuum device, an electron gun,
Alternatively, the present invention relates to a conductive rod-shaped single crystal processed body that can be used as a probe of a scanning probe microscope such as a scanning tunnel microscope or an atomic force microscope, and an assembly for measuring electrical characteristics using the same.

[0002]

2. Description of the Related Art Conventionally, it has been used for probe pins for measuring electrical characteristics of semiconductor integrated circuits, micro vacuum devices, electron guns, and probes for scanning probe microscopes such as scanning tunnel microscopes and atomic force microscopes. Various types of materials having properties and electron emissivity are used. For example, a probe pin for measuring electrical characteristics of a semiconductor integrated circuit is
It is used in a probe card for measuring electrical characteristics for removing defective products in the manufacturing stage of semiconductor integrated circuits. Hereinafter, the case of the probe pin for measuring the electrical characteristics of the semiconductor integrated circuit will be specifically described. In the manufacture of LSIs, measurements are made to test the operation of the circuit elements that make up each chip at the stage when the circuit elements are manufactured in the wafer, and then the chips cut from the wafer are placed in a package. , The TAB tape is mounted and the measurement for performing the operation test is performed again. Of these, the former usually uses a probe card having a probe pin made of a metal such as tungsten. The latter is often performed using a socket into which outer leads are inserted, but in the case of TAB, a probe card may be used. In most of these probe cards, a probe pin made of a tungsten wire is used, and the tip of the probe pin is bent into a dogleg shape so as to be brought into contact with the evaluation electrode portion of the semiconductor. Generally, in a probe card, in order to bring a plurality of probe pins into contact with the evaluation electrode of the semiconductor, the flatness of the tip of the probe pin, the flatness of the evaluation electrode portion of the semiconductor, and both when incorporated in the evaluation device Errors such as parallelism must be absorbed, and therefore the probe pin is designed to bend in the case of a tungsten wire. The amount by which the probe pin is bent is called overdrive. In a probe card using a tungsten wire, this overdrive is applied up to 100 μm. In the current probe card, such probe pins are arranged one by one so that they are aligned with the position of the semiconductor evaluation electrode.
Although it was manufactured by fixing the position, with the rapid miniaturization of semiconductors, it is difficult to fix the probe pins with high precision and high density, and the production of the probe card is limited.

Therefore, there has been devised a probe card in which fine probe pins are planted on a substrate vertically or at an appropriate inclination angle. For example, a method has been proposed in which a single crystal whose position is controlled on a silicon substrate is manufactured by the VLS method and applied to a probe pin for a probe card (Japanese Patent Laid-Open No. Hei 5).
-198636, JP-A-5-215774, and JP-A-5-218156). In these methods, a single-crystal pin whose position is controlled is grown on a Si substrate, and a substrate using a conductive rod-shaped single-crystal processed body which is made conductive by plating or the like is used as a probe card as it is. (Hereinafter, the electroconductive rod-shaped single crystal processed body of the present invention includes a probe pin for a probe card, and an assembly for measuring electrical characteristics using the same includes a probe card, which may be referred to as a probe pin and a probe card, respectively. Good).

However, the conventional VLS method probe pin has the following problems. In order for many probe pins to come into contact with the object to be inspected, for example, the semiconductor evaluation electrode part with good position accuracy and reliability, and proper evaluation can be performed, an appropriate amount of overdrive (deformation amount) due to buckling deformation of the probe pin is performed. It was not known that the influence on the reliability of the measurement and its factors are the aspect ratio, the diameter, and the protruding length from the fixed surface. Therefore, it is difficult to bring all the probe pins into contact with high positional accuracy and reliability, and there is a problem of lack of reliability. For example, the ratio of the tip diameter of the probe pin to the pin length is called the aspect ratio.If this aspect ratio is small, the overdrive cannot be applied to the probe pin, and when measuring with multiple probe pins, all probe pins cannot be loaded. Cannot contact the evaluation electrode portion of the semiconductor. Further, buckling deformation in the elastic region of the probe pin due to overdrive cannot be expected, and the probe pin is easily damaged. If the aspect ratio is too large, the workability during manufacture and use will be poor, the probe pins will be easily damaged, and the probe pins will buckle and come into contact with each other, and the load when contacting will be small and stable conduction will be obtained. I can't. If the diameter of the probe pin is too small, the probe pin is easily damaged, and if it is too large, it becomes impossible to cope with the high density of semiconductor terminals. Further, even if the protruding length of the probe pin from the fixed surface is too short or too long, an appropriate overdrive amount cannot be obtained. If the material of the conductive film is not appropriate, the conductive film at the tip of the probe pin will be peeled off by tens of thousands of contact, and the life of the probe pin will be shortened. If the coating thickness of the conductive plating is too thin, the resistance value of the probe pin becomes high, while if it is too thick, the elasticity of the probe pin is impaired and the probe pin is likely to be deformed. Further, the single crystal grown on the substrate by the VLS method can be made conductive and can be used as it is as a probe pin for a probe card. However, when a larger overdrive is required, it becomes easier to break than the root of the probe pin. , Reinforcement of the root was required, but the proper fixing method was not known. If the probe pin is not properly inclined with respect to the semiconductor terminal, the probe pin may slip on the terminal when it comes into contact with the semiconductor terminal. If the probe pins are composed of multiple pins with a narrow pitch,
The wiring from the probe pins can be pulled out from the current glass,
In the photolithography processing technology using an insulating substrate using epoxy or the like, it is very difficult to process the insulating substrate wiring at a fine pitch equivalent to that of the LSI by the semiconductor technology, and even if possible, the cost is high. turn into.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. It is hard to break and can be brought into contact with an object to be inspected with a high degree of positional accuracy. Uses a conductive rod-shaped single crystal processed body that is sufficiently conductive with the body, and further, the conductive rod-shaped single crystal processed body formed at a desired position with high accuracy and high density, and this conductive rod-shaped single crystal processed body It is an object of the present invention to provide an assembly for measuring an electric characteristic. In order to obtain the above-mentioned conductive rod-shaped single crystal processed body and an assembly for measuring electrical characteristics using the same, the inventors of the present invention have an aspect ratio (length / diameter d at the tip) of the conductive rod-shaped single crystal processed body, As a result of diligent study on methods and conditions such as the distance L (μm) between the fixed surface of the conductive rod-shaped single crystal processed body and the tip, the thickness t of the conductive film, the method for reinforcing and fixing the conductive rod-shaped single crystal processed body, An assembly for electrical property measurement that can be used to easily obtain an electrically conductive rod-shaped single crystal processed product of the present invention having good performance that has not been obtained in the past and that can be used for electrical property measurement for probe cards and the like. It came to complete the thing.

[0006]

The features of the present invention are VLS.
At least a side surface of a rod-shaped single crystal having an aspect ratio of 1 to 500 formed by a growth method or a rod-shaped single crystal having its tip alloy portion removed is coated with a conductive film having a thickness of 0.1 to 10 μm. The relationship between the distance L (μm) between the fixed surface of the electroconductive rod-shaped single crystal processed body and the tip and the diameter dμm of the rod-shaped single crystal is 10 ≦ L ≦ 3000, 0.1 ≦ d ≦ 600, d.
^A conductive rod-shaped single crystal processed product having a range of ^−2.4 · L ^2.8 ≧ 5.0 × 10 ⁴ and an assembly for measuring electrical characteristics using the same.

The thickness of the conductive film of the processed rod-shaped single crystal is preferably 0.1 to 10 μm, and the diameter d of the rod-shaped single crystal of the processed rod-shaped single crystal is 1 to 50 μm.
And the thickness of the conductive film is d × 0.4 μm or less,
More preferably, it is 0.1 μm or more. Further, it is preferable that at least the surface of the conductive film is Pd.

Further, it is preferable that the surface of the conductive rod-shaped single crystal processed body is covered with an insulating film having a thickness of 0.1 to 10 μm except at least the tip portion thereof.

The distance between the fixed surface of the electroconductive rod-shaped single crystal processed body and the tip is the distance between the substrate surface and the tip when the rod-shaped single crystal is formed integrally with the substrate. When the single crystal processed body is embedded in an insulating material or fixed by another method, it means the distance between the surface (tip side) of the insulating material and the tip.

The limit overdrive amount of these electroconductive rod-shaped single crystal processed bodies is preferably 1000 μm or less. Further, it is preferable that these electroconductive rod-shaped single crystal processed bodies are fixed at an angle of 80 ° to 90 ° with respect to the surface of the substrate or the surface of the insulating material.

The thickness of the fixing insulating material is 0.1.
The insulating material is preferably an epoxy resin, or a low melting point glass having a thermal expansion coefficient (1 / ° C) at 30 ° C to 250 ° C of 3.0 x 10 ^{-6 to} 8.0 x 10 ^-6. Is preferred.

In the electroconductive rod-shaped single crystal processed body of the present invention, for example, a rod-shaped single crystal body having a desired size and shape in which L and d described above fall within the scope of the present invention is formed on a substrate, and the surface is electrically conductive. May be formed integrally with the substrate by forming a conductive film, and the base of the conductive rod-shaped single crystal processed body and its periphery are exposed on the substrate on which the conductive rod-shaped single crystal processed body exists. Manufacturing is also performed by arranging a barrier plate having such a shape, covering the exposed portion of the base surface of the conductive rod-shaped single crystal processed body and the surrounding substrate surface with a fixing material made of an insulating material, and hardening and fixing the covering material. You can

When glass is used as the insulating material, the conductive rod-shaped single crystal processed body is present on the substrate at 30 ° C. to 250 ° C.
Thermal expansion coefficient (1 / ° C) at ℃ is 3.0 × 10 ^-6 ~
A low melting point glass of 8.0 × 10 ⁻⁶ is placed and melted by heating,
It can be manufactured by cooling.

The assembly for measuring electrical characteristics of the present invention is
The root of the conductive rod-shaped single crystal processed body is embedded and fixed with an insulating material, and the end of the processed body close to the insulating material is joined to the wiring of the wiring board. The electrically conductive rod-shaped single crystal processed body and the electrical characteristic measuring assembly obtained by joining the end portion close to the electrically conductive rod-shaped single crystal body and the wiring of the wiring board are manufactured as follows, for example. First, a dam plate having a shape such that the base of the conductive rod-shaped single crystal processed body and its periphery is exposed is arranged on the substrate on which the conductive rod-shaped single crystal processed body is present, and the conductive rod-shaped single crystal processed body is processed. An exposed portion of the substrate surface between the base of the body and the dam plate is covered with a fixing material made of an insulating material and hardened, and embedded in the insulating material to prepare a fixed conductive rod-shaped single crystal processed body.

Next, for example, by the following steps (1) to (4), the end of the conductive rod-shaped single crystal processed body, which is embedded and fixed by this insulating material, close to the insulating material and the wiring of the wiring board are connected. Bonding is performed to produce an assembly for measuring electrical characteristics. (1) A step of applying and curing an epoxy composition having an acid anhydride as a curing agent on a substrate on which a conductive rod-shaped single crystal processed body is present to form a cured product. (2) A step of removing the entire substrate. (3) A step of treating the cured product with an alkaline aqueous solution to expose both ends of the conductive rod-shaped single crystal processed body. (4) A step of joining the end face of the conductive rod-shaped single crystal processed body exposed by (3) to the wiring of the wiring board.

The electrical characteristic measuring assembly of the present invention is
It may be composed of the conductive rod-shaped single crystal processed body of the present invention and a semiconductor chip having a wiring for external extraction.

The present invention will be described in detail below. In the present invention
The conductive rod-shaped single crystal processed body used is shown in Fig. 1 (a).
The aspect ratio formed by the VLS growth method
(Rod length of the rod-shaped single crystal / the tip diameter d) is a rod of 1 to 500
-Shaped single crystal body 1 or the tip alloy part of the rod-shaped single crystal body is removed
At least the side surface of the container 1 has a conductivity of 0.1 to 10 μm.
One coated with film 2 or adjacent conductive rod-shaped single crystal
As shown in Fig. 1 (b) to avoid electrical contact between the work bodies
The thickness of the conductive rod-shaped single crystal processed body 3 excluding the tip.
A structure covered with an insulating film 4 of 0.1 to 10 μm
As shown in FIG. 1C, a substrate 5 on which a rod-shaped single crystal is formed,
It may be integrated, or the substrate may be removed
As shown in FIG. 1 (d), a desired conductive rod-shaped single crystal processed body 3 is desired.
The position of may be embedded and fixed by the insulating material 6.
Then, the fixed surface of the conductive rod-shaped single crystal processed body (for example, the above
The surface of the substrate 5 or the surface embedded and fixed with the insulating material 6) and the tip
To the distance L (μm) and the diameter d (μ
The relationship of m) is 10 ≦ L ≦ 3000, 0.1 ≦ d ≦ 60.
0, d ^-2.4× L^2.8≧ 5.0 × 10^FourBe in the range
is important.

VLS (Vapo) which is a method for forming a rod-shaped single crystal
r-liquid-Solid) growth method is RSWagner and WC El
lis: Appl. Phys Letters 4 (1964) 89. According to the method according to this document, a Si single crystal substrate on which Au particles are placed is heated to a temperature equal to or higher than the melting point of a Si-Au alloy in an atmosphere of a gas containing Si such as SiH4 and SiCl4, and Au on the Si single crystal substrate is heated. A rod-shaped Si single crystal is epitaxially grown on the particle mounting portion.

This method is applied not only to the case of Si single crystal, but also to the growth of other single crystals. For example, the growth of a LaB ₆ single crystal has a high melting point of 2530 ° C., a high evaporation rate, a high reactivity, and is not necessarily suitable for melt growth. From such a viewpoint, VLS growth capable of crystal growth at lower temperatures has been attempted (Journal of Crystal Gr
owth 51 (1981) 190-194). By the way, instead of placing Au particles, by combining photolithography, plating, vapor deposition, etching, etc.
By patterning the pads at arbitrary positions and performing VLS growth, it is possible to form a plurality of rod-shaped single crystal bodies standing at desired positions on the substrate, and this can be used as probe pins for measuring electrical characteristics. it can.

The rod-shaped single crystal body of the present invention comprises Si, LaB ₆ , GaAs, GaP, WO ₂ and S.
iC and the like, and particularly preferably Si and LaB ₆ . Alloys with these elements or compounds are Au, Pt, Ag, Cu, Pd, and Ga,
Particularly preferred are Au and Pt. The shape of the rod-shaped single crystal body used in the present invention is preferably a columnar shape or a shape close to it in consideration of the buckling load and the flexibility at the time of measuring electric characteristics, and the diameter d is 1 to 1 at the tip of the rod-shaped single crystal body. 600
μm, more preferably 5 to 300 μm, still more preferably 1 to 50 μm. The length of the rod-shaped single crystal is
10 μm or more, more preferably 200 μm to 5 m
m, and when it exceeds 5 mm, a large number of kinks and branches are generated when the rod-shaped single crystal body is formed by the VLS growth method. The rod-shaped single crystal body preferably has an aspect ratio of 1 to 500.
If the aspect ratio is less than 1, the rod-shaped single crystal is too short,
It cannot be used as a probe pin for measuring electrical characteristics, and if it exceeds 500, workability during manufacture and use is poor, the probe pin is easily damaged, buckling load is reduced, and stable conduction cannot be obtained. Further, the distance L (μm) between the fixed surface of the conductive rod-shaped single crystal processed body and the tip and the diameter d (μ
It is more preferable to select an aspect ratio in which m) is in the range of d ^−2.4 × L ^2.8 ≧ 5.0 × 10 ^{4 because} an appropriate limit overdrive amount can be obtained.

The rod-shaped single crystal formed by the VLS growth method necessarily has a tip alloy portion, but it is used for an electrical characteristic measuring assembly such as a probe card for measuring the electrical characteristic of a semiconductor integrated circuit. In this case, since the tip alloy part is relatively easily crushed, it is more preferable to use the tip alloy part from which it is removed in order to reduce the deformation. In addition, in order to improve the length accuracy of the plurality of conductive rod-shaped single crystal processed bodies, the rod-shaped single crystal bodies near the tip alloy portion may be simultaneously removed when the tip alloy portion is removed. The removal of the tip alloy portion can be performed at any stage of the process. For example, (1) V
After forming a rod-shaped single crystal by the LS growth method, (2) after forming a conductive film, (3) after embedding with an insulating material, and the like.
Further, when removing the tip alloy portion in any step, a part of the rod-shaped single crystal body may be removed at the same time as described above.

The tip alloy portion can be removed by various methods, and it is particularly preferable to remove it by a polishing method. Specific examples of the polishing method include polishing using a polishing pad or polishing abrasive grains. As the polishing pad, a pad to which abrasive grains such as aluminum oxide, silicon carbide and chromium oxide are attached is usually used. Also,
At the time of polishing, it is preferable to embed the rod-shaped single crystal body with polishing wax or the like and polish it in order to prevent the rod-shaped single crystal body from being broken.

As the substrate for VLS growth, a single crystal substrate made of the same material as the single crystal to be grown, or a substrate having a single crystal film made of the same material as the single crystal to be grown on an insulating substrate, etc. Can be used. For example,
A single crystal silicon substrate, a substrate in which single crystal Si is formed on the oxidized surface of the single crystal silicon substrate (SOI substrate), or the like is used. In addition, a substrate having a single crystal film formed on an insulating material such as sapphire can be used, but an SOI substrate is industrially easily obtained, which is preferable.

In the present invention, the SOI technique is premised on growing a rod-shaped crystal on an SOI substrate. As the SOI technology used in the present invention, a method of implanting oxygen ions in a single crystal Si substrate to form an oxidized region directly under the single crystal region (SIMOX; Porc.ISIAT
'83 1983 p.1855), a method of bonding a single crystal Si substrate to the oxidized surface of a surface-oxidized single crystal Si support substrate by heat treatment (Digest of the IEEE Int. Elec. Devices Meeti
ng (IEDM) 1985 p.684) and the like can be used.

The conductive rod-shaped single crystal processed body has a rod-shaped single crystal body formed by the VLS growth method in which at least the side surface has a thickness of 0.
It is coated with a conductive film having a thickness of 1 to 10 μm. When the thickness of the conductive film is 0.1 μm or less, the conductive film is torn or peeled off due to friction. Is not possible, and the cost is high. Particularly when the tip diameter d of the rod-shaped single crystal is 1 to 50 μm, the thickness of the conductive film is more preferably d × 0.4 μm or less.

This conductive film is formed by a method of coating the surface of the rod-shaped single crystal body using a vapor deposition method, a plating method, a dipping method or the like. Specifically, the rod-shaped single crystal body has N
An underlayer such as iP or Cr is formed by a plating method or a vapor deposition method, and then Au, Au-Ni, Au-C having excellent conductivity is formed.
There is a method of forming a film of a metal such as o, Au—Cr, Au—Cu, or Rh by a plating method. The material of the surface layer of this conductive film is P
The use of d is more preferable because the plating film at the tip of the probe pin is easily formed, the plating film is less likely to peel off, and the abrasion resistance is large. The conductive film covers at least the side surface of the rod-shaped single crystal body, but it is more preferable that the tip portion of the rod-shaped single crystal body is also coated with the conductive film.

If the wiring for external extraction is formed on the substrate on which the rod-shaped single crystal is grown, the conductive rod-shaped single crystal processed body can be used as it is as an assembly for measuring electrical characteristics in an integrated state with the substrate. You can This not only simplifies the production of the electrical characteristic measuring assembly, but also enables the production of the electrical characteristic measuring assembly in which a plurality of conductive rod-shaped single crystal processed bodies are accurately arranged. Further, according to this method, when used in a test such as a burn-in test of a semiconductor integrated circuit, which is subject to a heat load, the VLS growth substrate material is selected to be the same as the substrate material of the DUT, so that the difference in thermal expansion coefficient is increased. It is possible to greatly improve the positional deviation between the terminal of the object to be inspected and the probe pin. When the conductive rod-shaped single crystal processed body and the substrate are not used in an integrated state, the conductive single crystal processed body is reinforced by embedding the base of the conductive single crystal processed body with an insulating material (Fig. 1 (d))
Can be used in.

As the insulating material for embedding the conductive rod-shaped single crystal processed body in the present invention, resin, glass, ceramics or the like can be used. As the resin, as the thermosetting resin which is a thermosetting resin and a thermoplastic resin, there are an epoxy resin, an acrylic resin, a silicon resin, a urethane resin, a polyimide resin, and the like, and as the thermoplastic resin, Examples include olefin resins and styrene resins. An epoxy resin is particularly preferable. An inorganic filler can be added to these resins and used. As the inorganic filler, Si
O ₂ , Al ₂ O ₃ or the like is used.

The thickness (T in FIG. 1D) of embedding with an insulating material such as resin or glass is not particularly limited, but is 0.1.
˜2000 μm is preferred. If the thickness is too thin, the strength is insufficient, and if it is too thick, the position accuracy of the tip of the conductive rod-shaped single crystal processed body tends to be deteriorated, and the length of the single crystal processed body becomes too long, which makes it difficult to manufacture. become. 0.5-2m
A thickness of m is more preferable because it is easy to manufacture and an appropriate fixing strength can be obtained. Also, L is 10 to 3000 μ
m, that is, the side of the conductive rod-shaped single crystal processed body embedded with the insulating material that contacts the object to be inspected is 10 from the surface of the insulating material.
-3000 μm is projected. If it is less than 10 μm, the electroconductive rod-shaped single crystal processed body is easily damaged, and if it is longer than 3000 μm, the amount of overdrive is large and it is difficult to manufacture and use, which is not preferable.

Further, FIG. 1 (e) shows a state in which the end portion of the conductive rod-shaped single crystal processed body according to the present invention is pressed against the object to be inspected. The conductive rod-shaped single crystal processed body depends on the load in the pressing direction. To transform. This deformation amount δ is called an overdrive amount.
When the load is increased, the load and the amount of deformation change in proportion to each other in the initial stage, but eventually the load becomes constant and finally the fracture occurs. The drive amount at this time is the limit overdrive amount (δ
_max ) and the load at this time is called buckling load. Furthermore,
As shown in FIG. 1 (f), the conductive rod-shaped single crystal processed body is fixed at an angle of 80 ° to 90 ° with respect to the surface of the substrate or the insulating material (here, the substrate 5 is shown). It is preferable. As a result, the measurement surface of the semiconductor integrated circuit and the conductive rod-shaped single crystal processed body come into contact with each other at an angle of 80 ° to 90 °. For example, the conductive rod-shaped single crystal processed body of the present invention is attached to the probe pin of the probe card. When used as
Longer probe pin life. Further, the probe pin has good positional accuracy, and is particularly effective as an electrical characteristic measuring assembly for a high density and fine probe card. Further, when the angle of inclination is 80 ° or more and less than 90 °, the bending directions are the same, and even if the bending amount is large, there is no contact between the probe pins and reliable conduction can be obtained.

After the base of the conductive single crystal processed body formed on the substrate is embedded with an insulating material, the substrate is removed and the conductive single crystal processed body fixed with the insulating material is assembled into an assembly for measuring electrical characteristics. When it is used as a product, it is preferable to use it by joining it to a wiring board 9 for external drawing as shown in FIG. FIG. 2 (a) shows a schematic view of an electrical characteristic measuring assembly produced by joining the end portion of the conductive rod-shaped single crystal processed body to the wiring 8 of the wiring board, and FIG. 2 (b) shows a cross section thereof. The figure is shown.

Next, a method for manufacturing an assembly for measuring electrical characteristics using the processed conductive single crystal of the present invention will be described. A manufacturing method in the case of embedding a conductive rod-shaped single crystal processed body using a resin as an insulating material will be described below with reference to FIG.

On the substrate 5 on which the conductive rod-shaped single crystal processed body 3 is present, the barrier plate 10 having a shape such that the base of the conductive rod-shaped single crystal processed body and its periphery is exposed (FIG. 3).
(A)). Next, the base of the conductive rod-shaped single crystal processed body and the exposed portion of the substrate surface around the base are covered with the fixing material 11 and cured to fix the conductive rod-shaped single crystal processed body (FIG. 3).
(B)). It is also possible to form the wiring for external drawing on the substrate as it is in a state of being integrated with the substrate and use it as an electrical characteristic measuring assembly, but after removing the substrate (see FIG. 3).
(C)) Alternatively, the wiring board 9 manufactured separately may be connected and used (FIG. 3 (d)).

At this time, the end of the insulating material, which embeds the electroconductive rod-shaped single crystal processed body obtained in the above step, on the wiring board side, preferably the end surface as it is, or after attaching a gold bump, or , After the insulating material is etched so that the end of the conductive rod-shaped single crystal processed body is slightly projected, the end surface of the conductive rod-shaped single crystal processed body is left as it is, or after the gold bump is attached, it is bonded to the wiring of the wiring board. Then, an electrical characteristic measuring assembly as shown in FIG. 3D is obtained.

Here, the reason why the dam plate is used for fixing with a fixing material is that if the dam plate is not used and only the fixing material is used for fixing, the space between probe pins may not be filled or the reverse may occur due to the viscosity of the fixing material. There are problems such as crawling up to the tip of the probe pin and flowing out to the outside. The barrier plate may be made of any material that is chemically stable and has a high reinforcing effect. For example, heat-resistant resin such as epoxy resin, polyimide resin, polyphenylene oxide (PPO), or insulating material such as glass or ceramics can be used.

In these methods, it is ensured that the end of the conductive rod-shaped single crystal processed body embedded with the insulating material on the side in contact with the wiring board is projected from the surface of the resin cured product and the wiring of the wiring board. This is to achieve proper joining. The protruding length is 10-1
00 μm is preferable. If it is less than 10 μm, it is difficult to bond it to the wiring of the wiring board, and if it is more than 100 μm, it is likely to cause a positional deviation, and in any case, a conduction defect between the conductive rod-shaped single crystal processed body and the wiring board occurs and the manufacturing yield deteriorates. Let

Further, an assembly for measuring electrical characteristics, which is one of the present invention, comprising a conductive rod-shaped single crystal processed body and a semiconductor chip having wiring for external extraction is a conductive rod-shaped single crystal arranged at a narrow pitch. It is possible to easily establish electrical continuity with the outside of the processed body, and it is possible to easily form a substrate made of the same material as the inspection object, such as Si or GaAs, by using an LSI processing technique.
Particularly in the case of a multi-type probe card that simultaneously measures a plurality of objects to be inspected in the state of a wafer, when it is difficult to arrange the wiring for external extraction, it is possible to easily deal with it by forming the wiring of the semiconductor chip in multiple layers. .

[0038]

The present invention will be described in detail with reference to the following examples.

Example 1 and Comparative Example 1 The same pattern as the wiring board was formed on the SOI substrate in which the single crystal Si 18 was formed on the oxide film (SiO ₂ ) 17 of the single crystal Si substrate 16 by using the photolithography method. The Au vapor deposition film 19 having a shape was formed to a thickness of 0.03 μm (FIG. 4A). next,
Strong acid etchant (HF / HNO ₃ / CH ₃ COOH
Si) of the exposed portion is removed by etching, and then the Au deposition film 19 is removed by an etching solution (mixed solution of KI / I / H ₂ O) (FIG. 4).
(B)). Then, at a predetermined position where the rod-shaped single crystal is grown, an Au base film 20 having the same shape as the rod-shaped single crystal is formed with a thickness of 0.03 μm by using a photolithography method, and the Au-shaped film having the same shape is formed thereon. The pad 21 was formed by 2 μm electroless plating (FIG. 4 (c)). 95 in the reaction tube
The mixture was heated to 0 ° C. and a mixed gas of silicon tetrachloride and hydrogen was flowed to obtain a rod-shaped single crystal body 22. In this case, Au with a diameter of 30 μm
300 pads were arranged at a pitch of 60 μm (only three pads are shown in the figure). VLS growth was carried out for about 6 hours until the rod-shaped single crystal 22 had a length of 1.5 mm.
At that time, the diameter of the tip is 9 μm and the length is just 1.5.
mm. Next, the polishing wax 24 was poured into the rod-shaped single crystal body 22 until it was filled and solidified (FIG. 4).
(D)). The Si-Au alloy 23 side of this rod-shaped single crystal is wet-polished, the Si-Au alloy 23 is removed, the surface formed by the tip of the rod-shaped single crystal is further flattened, and then the polishing wax 24 is removed with acetone. did. The length of the obtained rod-shaped single crystal was 1000 ± 2 μm, the length accuracy was good, and the diameter of the tip was 10 μm. Next, the Ni—P underlayer film 25 is selectively formed in a thickness of 0.5 μm by electroless plating only on the exposed portion of Si.
An Au film 26 of 2 μm is formed on the surface of the No. 2 by electroplating, and a Pd film 27 of the outermost surface is further formed by 0.5 μm of electroplating (FIG. 4 (e)). 2, 4, 11 and 12 conductive rod-shaped single crystal processed bodies were produced ( Indicates a comparative example, and the same applies hereinafter). Furthermore, the aspect ratio, the diameter of the Au pad, the pitch, the growth time, and the Ni-P, A of the conductive film.
Similar conductive rod-shaped single crystal processed bodies (Nos. 7 and 14 in Table 1) were produced by changing the film thicknesses of u and Pd. And further,
The same conductive rod-shaped single crystal processed body (No. 1 in Table 1) was formed by changing the aspect ratio, the diameter of the Au pad, the pitch, the growth time, and the thickness of the conductive film without applying Pd plating to the outermost layer.
3, 5, 6, 8, 15 ) were produced. In addition, No. 1 in Table 1
In Nos. 1, 9 and 10 , the conductive film was formed only by the vapor deposition film of Au. The conductive rod-shaped single crystal processed bodies have the same size Table 1
No. 2 and No. Although 3 is the difference only in the presence or absence of Pd plating of the outermost layer, these conductive rod-shaped single crystal processed bodies were joined to a wiring board to prepare an assembly for measuring electrical characteristics, and a durability test was conducted. No. with Pd plating on the outermost layer No. 2 has durability. It was confirmed that it was improved several times as compared with 3. In this durability test, the conductive rod-shaped single crystal processed body and the Au vapor-deposited film of the object to be measured were brought into contact with each other with an overdrive of 10 μm, and the tip plating film of the conductive rod-shaped single crystal processed body was peeled tens of thousands of times. I decided what would happen in.

[0040]

[Table 1]In addition, No. 1 to No. 15 conductive rod-shaped single crystals
The processed body is bonded to the wiring board as described above, and the electrical characteristics
Make a measurement assembly and evaluate other characteristics by the following methods.
The results obtained are shown in Table 2. The diameter of the single crystal is 0.0
Create a conductive rod-shaped single crystal processed product with a length of 5 μm and a length of 50 μm
However, the conductive film could not be formed properly. Single bond
If the crystal diameter is 650 μm, the length should be 5000 μm.
Even d ^-2.4× L^2.8Is 4.0 x 10³And small, over the limit
-The amount of drive is small, and you can obtain only low reliability.
won.

[0041]

[Table 2]

(Limit Overdrive Amount) A load was applied to the electrical characteristic measuring assembly in this example, and the pushing amount until the first probe pin was broken was measured, and the value was taken as the limit overdriving amount. Here, this limit overdrive amount was measured using a digital displacement meter (accuracy ± 1 μm). (Position Accuracy) The position of the tip of the probe pin was measured with an optical microscope, and the amount of positional deviation from the design value was obtained. (Height accuracy) The height of the probe pin tip was measured with an optical microscope, the plane formed by the pin tip was determined, and the maximum deviation from that plane was defined as the height accuracy. (Deformation of Probe Pin) After the probe pin was subjected to buckling deformation 10 times with overdriving of 10 μm by the above-mentioned limit overdrive measuring device for probe pin, the presence or absence of deformation was examined with a microscope. (Surface property of probe pin) Scanning electron microscope (SEM)
The presence or absence of defects in the plating film on the side surface of the probe pin was determined by using. (Short circuit between probe pins) Alumina plate, which is an insulator, is pressed against the pins to check if insulation between different probe pins is maintained with a 10 μm overdrive. It was judged by measuring. At this time, when the resistance between the probe pins was 1 MΩ or less, it was determined that the pins were in contact with each other and were electrically short-circuited. (Conductivity test) Using a commercially available multimeter, it was judged from the resistance value whether the tip of the pin and the wiring of the wiring board were electrically connected. When this resistance value was 50Ω or more, it was determined that there was no conduction.

(Example 2) At a predetermined position where a rod-shaped single crystal body is grown on the single-crystal Si substrate 5, a photolithography method is used, and an Au base film 20 having the same shape as the rod-shaped single crystal body is used.
With a thickness of 0.03 μm, on which Au of the same shape is formed.
The pad 21 was formed by 2 μm electroless plating (FIG. 5).
(A)). This Si substrate 5 is HF / HNO ₃ / CH ₃ C
Etching was performed using a mixed solution of OOH to form a mesa shape 28 of Si and a gold pad 21 was placed on the mesa shape 28 (FIG. 5B). This was heated to 950 ° C. in a reaction tube and a mixed gas of silicon tetrachloride and hydrogen was caused to flow to obtain a rod-shaped single crystal body 22. In this case, 6 Au pads with a diameter of 35 μm are used.
300 pieces were arranged at a pitch of 0 μm (only three pieces are shown in the figure), and the VLS-grown rod-shaped single crystal body 22 had a length of 2500 μm and a tip diameter of 24 μm. Next, the polishing wax 24 was poured into the rod-shaped single crystal body 22 until it was filled and solidified (FIG. 5C). The Si-Au alloy 23 side of this rod-shaped single crystal body was wet-polished to obtain Si.
After removing the Au alloy 23 and flattening the surface formed by the tip of the rod-shaped single crystal body, the polishing wax 24 is added with acetone.
Was removed (FIG. 5 (d)). The rod-shaped single crystal obtained had a length of 2000 ± 2 μm, and the tip diameter was 25 μm.
It was m. After that, the rod-shaped single crystal Ni-P base film 2
5 is deposited by electroless plating to a thickness of 0.5 μm, an Au film 26 is deposited on the surface of the Ni—P undercoat film 25 by electrolytic plating to a thickness of 4 μm, and an outermost Pd film 27 is deposited by 0.5 μm by electrolytic plating. (Fig. 5 (e)). Next, on the substrate of the conductive rod-shaped single crystal processed body obtained as shown in FIG. 5, the conductive rod-shaped single crystal processed body 3 (here, the rod-shaped single crystal body and the conductive film is the conductive rod-shaped single crystal processed body 3 is formed).
(Fig. 3A), a barrier plate 10 having a shape such that the base portion of the conductive rod-shaped single crystal processed body 3 and the periphery thereof are exposed is arranged (Fig. 3A). The plate was made of semi-cured epoxy resin and adhered onto the substrate with uncured epoxy resin. Next, a fixing material made of an uncured epoxy resin is applied to the base portion of the conductive needle-like single crystal body 3 and the portion exposed between the barrier plates 10. Next, this epoxy resin was heated and cured to prepare a cured product 11 (FIG. 3 (b)).
The epoxy resin composition in this case was made by mixing 100 g of bisphenol A type epoxy resin with 80 g of methyltetrahydrophthalic anhydride, 2 g of 2.4.6-trisphenol, and 100 g of kaolin clay powder. The semi-cured epoxy resin used for the barrier plate is made by curing the above-mentioned epoxy resin composition in an oven at 100 ° C. for 50 minutes, and after applying the uncured epoxy resin, the entire heat curing is not performed. It was performed at 100 ° C. for 5 hours. At this time, the length of the conductive rod-shaped single crystal processed body protruding from the epoxy resin surface was 1000 μm. Next, the Si substrate 5 was removed by polishing using wet polishing (FIG. 3C). At this time, the thickness of the epoxy resin was about 1000 μm, and the lower end portion of the conductive rod-shaped single crystal processed body was projected by 50 μm from the epoxy resin surface as measured by an optical microscope. The lower end face of this conductive rod-shaped single crystal processed body and the wiring 8 on the wiring substrate 9
And No. 3 in Table 3 are adhered to each other. The electrical characteristic measuring assembly shown in FIG. 25 could be produced (FIG. 3 (d)). By the same method, the aspect ratio, the Au pad diameter, the pitch, the growth time, the thickness of the conductive film and the film forming method were changed to prepare the conductive rod-shaped single crystal processed body shown in Table 3.

[0044]

[Table 3]

These were joined to a wiring board to prepare an assembly for measuring electrical characteristics. As a result of evaluating these in the same manner as in Example 1, the results shown in Table 4 were obtained.

[0046]

[Table 4]

(Embodiment 3) As shown in FIG.
(No. 2 in Table 1) A masking tape 29 is attached to a portion of the conductive rod-shaped single crystal processed body that is connected to the external wiring (FIG. 6A), and a solution of a polyamic acid that is a precursor of polyimide. The conductive rod-shaped single crystal processed body was left in a Petri dish 31 containing 30 with the tip thereof facing upward so that one-third of the length of the conductive rod-shaped single crystal processed body was immersed (FIG. 6).
(B)). Then, the solution crawls to the tip of the pin due to surface tension (Fig. 6 (c)), but about 100μ from the tip.
When the solution has climbed up to about m, it is taken out of the solution, the masking tape 29 is peeled off, and heat curing (250
(° C, 30 minutes) (FIG. 6 (d)). Thus, the polyimide insulating film 32 having a thickness of 0.1 μm is formed on the surface of the conductive rod-shaped single crystal processed body.
o. The electrically conductive rod-shaped single crystal processed body shown in FIG. 4 could be produced. In addition, by changing the concentration of polyamic acid by the same method, No. 1 in Table 1 was changed. The conductive rod-shaped single crystal processed bodies shown in Nos. 6 and 8 were produced. This method can also be applied to the second embodiment. In the case of Example 2, the insulating film is formed by using the above-described method before disposing the dam plate on the obtained conductive rod-shaped single crystal processed body. In this case, no masking tape is required because no wiring is provided. After that, a weir plate was used in Example 2.
The same process as above is performed, and the same process is performed thereafter, and the conductive rod-shaped single crystal processed body (Table 3
No. 15, 20, 26-29) could be made. The conductive rod-shaped single crystal processed body thus obtained was joined to a wiring board to prepare an assembly for measuring electric characteristics, and the assembly was evaluated by the same method as in Example 1. As a result, the results shown in Tables 2 and 4 were obtained. Was obtained.

(Embodiment 4) An embodiment of an assembly for measuring electrical characteristics, which is composed of a conductive rod-shaped single crystal processed body and a semiconductor chip having a wiring for external extraction, will be described below with reference to FIG. FIG. 7A is a schematic view of the electrical characteristic measuring assembly obtained in this example, and FIG. 7B is a sectional view thereof. The conductive rod-shaped single crystal processed body 3 was produced in the same manner as in Example 2. At this time, the conductive rod-shaped single crystal processed body had a pitch of 50 μm, and a total of 600 pieces were produced within a 5 mm square (only 16 pieces were shown in FIG. 7). The external lead wiring semiconductor chip 33 was manufactured on a Si substrate by an LSI manufacturing technique, and the wiring 34 was manufactured in a two-layer structure. This semiconductor chip had a size of 45 mm square, and the width of the wiring was 25 μm for connecting to the conductive rod-shaped single crystal processed body, and the width on the extraction side was 127 μm. The electrically conductive rod-shaped single crystal processed body produced in this manner and the semiconductor chip having the above-mentioned wiring for external extraction could be joined together to make an electrical characteristic measuring assembly. By using this semiconductor chip, the conductive rod-shaped single crystal processed body was easily connected to the external wiring, and an electrical measurement assembly having highly reliable and high-density probe pins could be manufactured.

[0049]

As described above, according to the present invention,
A conductive rod-shaped single crystal processed body that is hard to be damaged and can be brought into contact with an object to be inspected with high positional accuracy, and has sufficient electrical continuity with the object to be inspected. It has become possible to provide a conductive rod-shaped single crystal processed body, and an assembly for measuring electric characteristics using these conductive rod-shaped single crystal processed bodies. Further, the electroconductive rod-shaped single crystal processed body of the present invention is not limited to the above-mentioned embodiment, and is not limited to a probe card, and includes a micro vacuum device, an electron gun, a scanning tunneling microscope and an atomic force microscope. The present invention can be effectively used as a probe of a scanning probe microscope.

[Brief description of drawings]

FIG. 1 is a view showing an example of a conductive rod-shaped single crystal processed body of the present invention.

FIG. 2 is a view showing an embodiment of the electrical property measuring assembly of the present invention.

FIG. 3 is a diagram showing an embodiment of a manufacturing process of the electrical characteristic measuring assembly of the present invention.

FIG. 4 is a diagram showing an embodiment of a manufacturing process of the electrical characteristic measuring assembly of the present invention.

FIG. 5 is a diagram showing an embodiment of a manufacturing process of the electrical characteristic measuring assembly of the present invention.

FIG. 6 is a view showing an embodiment of the manufacturing process of the electrical characteristic measuring assembly of the present invention.

FIG. 7 is a view showing an embodiment of the electrical property measuring assembly of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1; Rod-shaped single crystal body 2; Conductive film 3; Conductive rod-shaped single crystal processed body 4; Insulating film 5; Substrate 6; Insulating material 7; DUT 8; Wiring 9; Wiring board 10; Dam plate 11; Insulation Fixing material 12; epoxy cured material 13; polymer compound film 16; single crystal Si substrate 17; Si oxide film 18; single crystal Si 19; Au deposition film 20; Au base film 21; Au pad 22; rod-shaped single Crystalline body 23; Si-Au alloy 24; Polishing wax 25; NiP base film 26; Au film 27; Pd film 28; Mesa shape 29; Masking tape 30; Polyamic acid solution 31; Petri dish 32; Polyimide insulating film 33; External Leader wiring semiconductor chip 34; wiring

Claims (8)

[Claims] 1. A rod-shaped single crystal having an aspect ratio of 1 to 500 formed by a VLS growth method or a rod-shaped single crystal having its tip alloy portion removed has at least a side surface of 0.1 to 10 μm.
The distance L (μm) between the fixed surface and the tip of the conductive rod-shaped single crystal processed body coated with a conductive film having a thickness of 5 mm and the diameter d (μm) of the rod-shaped single crystal are within the following ranges: A conductive rod-shaped single crystal processed body characterized by: 10 ≦ L ≦ 3000, 0.1 ≦ d ≦ 600, d ^−2.4 × L
^2.8 ≥ 5.0 x 10 ⁴ 2. The conductive rod-shaped single crystal processed body according to claim 1, wherein the conductive rod-shaped single crystal processed body is fixed with an insulating material. 3. The insulating material has a thickness of 0.1 μm to 2000 μm.
The conductive rod-shaped single crystal processed product according to claim 2, which has a thickness of μm. 4. The conductive rod-shaped single crystal processed body according to claim 1, wherein at least the surface of the conductive film is Pd. 5. The processed conductive rod-shaped single crystal according to claim 1, wherein the diameter d of the rod-shaped single crystal is 1 to 50 μm, and the thickness t of the conductive film is d × 0.4 μm or less. 6. The electroconductive rod-shaped single crystal processed product according to claim 1, wherein the surface thereof is covered with an insulating film having a thickness of 0.1 to 10 μm except at least the front end face thereof. 7. An electrical characteristic measuring assembly comprising the conductive rod-shaped single crystal processed body according to claim 1 and a circuit board having a wiring for external drawing. 8. The circuit board is a semiconductor chip.
Assembly for electrical properties as described.