JP2002071712A - Probe card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe card which achieves excellent mechanical characteristics to eliminate possible poor contact with a probe, a large withstand voltage to hinder electric breakdown between through holes and a higher thermal conductivity to follow temperature changes in a silicon wafer quickly with a fast temperature matching. SOLUTION: The probe card is formed on a semiconductor wafer to be used for the inspection of an IC circuit and comprises a ceramic substrate made of non-oxide ceramics with the porocity thereof of 0 or 5% or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a probe card used for determining whether a circuit or the like formed on a silicon wafer or the like operates normally.

[0002]

2. Description of the Related Art A semiconductor chip (semiconductor element) is prepared by thinly slicing an ingot of silicon single crystal or the like formed using a single crystal pulling apparatus to produce a semiconductor wafer. The integrated circuit is manufactured through a process of forming the integrated circuit and then dividing the integrated circuit into units.

In the manufacturing process of the semiconductor chip,
After forming an integrated circuit composed of a large number of units on a semiconductor wafer, it is necessary to check whether or not these circuits operate normally before dividing into semiconductor elements (semiconductor chips) of each unit. Therefore, for such an inspection, an inspection device is used in which a needle-like metal called a probe is pressed against a terminal pad of a silicon wafer to flow an electric current, and the continuity of the integrated circuit and the insulation between the circuits are checked. .

At present, as the degree of integration of semiconductor elements increases, the degree of integration of circuits formed on silicon wafers increases, and the pitch of terminal pads formed on semiconductor elements decreases.
Therefore, it is necessary to narrow the interval between the probes used in the inspection apparatus, and the head (performance board) of the inspection apparatus is required.
In addition, it is difficult to directly attach the probe. In order to cope with such a problem, recently, an inspection apparatus has been used in which a relay board (probe card) is interposed and a contactor board on which a probe is provided is attached to a head (performance board).

In the above inspection apparatus, the probe card used as the relay board is made of resin or an oxide ceramic such as an alumina ceramic board, and connects the wide pitch terminals of the performance board to the narrow pitch probes of the contactor board. (Patent No. 2
796070).

[0006]

At present, when inspecting an integrated circuit formed on a silicon wafer, not only an operation state at normal temperature but also an operation state at a high temperature of 100 ° C. or higher is required. And presses the probe against terminal pads on the silicon wafer with considerable pressure.
However, the strength of the probe card made of the above-mentioned resin substrate or alumina ceramic substrate at room temperature cannot be said to be sufficient, and the strength decreases at high temperature. For this reason, there is a problem that deformation such as warpage or undulation occurs in the probe card itself, and accurate inspection cannot be performed.

[0007] Further, since the resin substrate or the alumina ceramic substrate has a large coefficient of thermal expansion, when the temperature rises, the contact position with the probe is displaced or warped, and poor contact with the probe occurs. In some cases, an error occurred in the inspection. Further, the resin substrate and the alumina ceramic substrate have a low thermal conductivity, so that the temperature rise and the high temperature cannot be quickly performed, so that an efficient inspection cannot be performed.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to solve the above problems at ordinary temperature,
A probe with excellent mechanical strength at high temperatures, no poor contact with the probe, no warping or deformation even at high temperatures, quick temperature matching that quickly follows the temperature rise / fall of the silicon wafer, and high withstand voltage at high temperatures To provide a card.

[0009]

In order to achieve the above object, a probe card according to the present invention is a probe card used for inspecting a circuit formed on a semiconductor wafer,
It is made of a ceramic substrate made of a non-oxide ceramic, and has a porosity of 0 or 5% or less.

The probe card of the present invention comprises a ceramic substrate made of a non-oxide ceramic such as a carbide ceramic or a nitride ceramic and has a low porosity of 5% or less.
It has excellent mechanical properties (strength) at room temperature and high temperature, and does not warp or deform even at high temperature. Therefore, a contact failure with the probe does not occur.

The ceramic substrate has a porosity of 5%.
% Or less and the volume ratio of pores in the ceramic substrate is small, so that even when a voltage is applied at a high temperature where the volume resistivity of the ceramic decreases, electrons jump in the air in the pores. Further reduction in volume resistivity is unlikely to occur. Therefore, the withstand voltage of the ceramic substrate can be kept high, and dielectric breakdown is hard to occur between the through holes.

The ceramic substrate has a porosity of 5%.
% Or less, the coefficient of thermal expansion is almost the same as the coefficient of thermal expansion of the material constituting the ceramic substrate, and is not so different from the coefficient of thermal expansion of a silicon wafer or the like. Therefore, the contact position with the probe does not shift at a high temperature.

Further, the ceramic substrate has a porosity.
The thermal conductivity is as low as 5% or less, and there is no decrease in the thermal conductivity due to the presence of pores, so the thermal conductivity is large. Therefore, the temperature matching is fast, and it is possible to quickly follow the temperature change of the silicon wafer. When the porosity exceeds 5%, the body voltage is reduced due to the electrons jumping in the air in the pores, and dielectric breakdown between the through holes is liable to occur.

The probe card is disclosed in Japanese Unexamined Patent Publication No.
JP-A-140484 and JP-A-4-152270 disclose ceramic probe cards, but do not disclose (disclose) what kind of ceramic is used, and refer to JP-A-7-98380. Although the gazette discloses a probe card composed of a glass epoxy substrate and an aluminum nitride support plate, probing is performed only on the glass epoxy substrate, and aluminum nitride only functions as a support. It should be noted that, unlike the present invention in which circuits and through holes are formed in a nitride ceramic, the patentability of the present invention is not hampered by these known documents.

In the above probe card, it is desirable that the pore diameter of the largest pore in the ceramic substrate is 50 μm or less. Since the size of the pores is small, the amount of air in the pores decreases, and when a voltage is applied, electrons do not easily jump in the air, so that the withstand voltage can be kept higher. The mechanical properties and warpage of the ceramic substrate are smaller, and the thermal conductivity is higher.

When the pore diameter exceeds 50 μm, it becomes difficult to secure a withstand voltage characteristic at a high temperature, particularly at a high temperature, and a short circuit or the like may occur. The maximum pore diameter is 10 μm
The following is more desirable. This is because the amount of warpage at a high temperature (for example, 100 ° C. or higher) is reduced.

The porosity is measured by the Archimedes method. Pulverize the sintered body, put the pulverized material in an organic solvent or mercury, measure the volume, calculate the true specific gravity from the weight and volume of the pulverized material, and calculate the porosity from the true specific gravity and the apparent specific gravity .

The maximum pore is defined by taking an image of an arbitrary 10 points with an electron microscope, selecting the largest pore in the visual field, and defining the average value of the maximum pore as the pore diameter of the maximum pore. . Further, the porosity may be 0%. Ideally, no porosity is present.

The porosity and the maximum pore diameter can be adjusted by the pressing time, pressure, temperature, and additives such as SiC and BN during sintering. As described above, since SiC and BN inhibit sintering, pores can be introduced. The presence of pores increases the toughness value. Therefore, the pores may be present to such an extent that the strength does not decrease so much.

In the above probe card, it is desirable that the ceramic substrate is provided with a through hole at least inside. In the inspection apparatus as shown in FIG. 1, since a probe card is interposed between the head (performance board) and the contactor board, a through hole is required for conducting from one face to the other face. Because.

In the above probe card, it is preferable that a conductor circuit is formed on one main surface of the ceramic substrate. This is for expanding the inspection pitch in the probe and connecting it to the head (performance board).

In order to increase the inspection pitch, as shown in FIG. 1, it is desirable to provide a conductor circuit for increasing the probe pitch on the surface of the ceramic substrate because it is relatively easy. A conductor circuit for expanding the probe pitch may be provided inside.

Some probe cards do not require through holes. In this case, it is sufficient that a conductor circuit is formed only on one main surface.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the probe card of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram schematically illustrating an example of a semiconductor wafer inspection apparatus using the probe card of the present invention, and FIG. 2A is a cross-sectional view schematically illustrating the probe card of the present invention. , (B) is a plan view thereof.

The inspection apparatus 10 includes a performance board 24 on which terminals for inspection are arranged, and a lifting / lowering apparatus 22 for adjusting the position of the performance board 24 in the X, Y, and Z directions.
And the silicon wafer 60 through the performance substrate 24
And a tester 20 for applying a current thereto to determine the suitability.

Below the performance board 24, a probe board 30 and a probe card 40 are sequentially arranged.
Are provided, and the wiring pitch is reduced by passing through the probe board 30 and the probe card 40. Further, the connection with the terminal pads 61 formed on the silicon wafer 60 is established through the probes 52 of the contactor substrate 50 provided below the probe card 40.

The probe 52 is provided on the contactor substrate 50 so as to penetrate the contactor substrate 50 and protrude from the upper surface and the lower surface. The probe protruding from the upper surface contacts the terminal pads of the probe card. The probe protruding from one bottom surface comes into contact with a terminal pad provided on the silicon wafer.

The inspection apparatus 10 has a table 26 for mounting a silicon wafer 60 on which a circuit is formed.
The table 26 can be adjusted in the X, Y, and Z directions. Further, below the table 26, a heater 28 for heating the silicon wafer 60 and a cooling device 29 using a Peltier mechanism or the like for cooling the silicon wafer 60 are provided. Electric power is supplied.

Next, the inspection of the silicon wafer 60 using the inspection apparatus 10 will be described. First, table 2
6, the silicon wafer 60 is placed on the silicon wafer 60.
The positioning mark formed above is read by an optical device (not shown), and the position of the table 26 is adjusted. Thereafter, the performance substrate 24 and the like are pushed down by the elevating device 22, and the probes 52 of the contactor substrate 50 are pressed against predetermined terminal pads of the silicon wafer 60. In FIG. 1, the terminal pads are shown as raised, but the actual thickness of the terminal pads is 1 to 50 μm.

Thereafter, the tester 20 continuously applies a current to predetermined terminal pads 61 of the silicon wafer 60 via the performance board 24, the probe board 30, the probe card 40, and the contactor board 50, thereby forming the silicon wafer. A characteristic test is performed to determine whether the continuity of the conducted conductor circuit or insulation is maintained in a portion where insulation is required. At this time, the inspection can be performed while cooling or heating the silicon wafer by using the cooling device 29 and the heater 28.

Next, the probe card of the present invention used in the above inspection apparatus will be described. As shown in FIG. 2, a through-hole 42 is provided inside a ceramic substrate 41 made of a non-oxide ceramic that constitutes the probe card 40.
Are provided on the bottom surface 41b, and a terminal pad 43 for contacting the probe of the contactor substrate 50 is provided. On the upper surface, a conductor circuit 44 and a terminal pad 45 for expanding the pitch are provided. .

Therefore, by using the probe card 40, the connection between the relatively wide pitch terminal pads formed on the performance substrate 24 and the narrow pitch terminal pads 61 formed on the silicon wafer 60 can be ensured. (See FIG. 1).

The probe card 40 of the present invention is made of a ceramic substrate 41 made of a non-oxide ceramic and has a porosity of 5% or less. ), No warping or deformation even at high temperatures, and no poor contact with the probe occurs. Further, the withstand voltage of the ceramic substrate can be kept high.

Further, since the ceramic substrate has a small coefficient of thermal expansion and is close to the coefficient of thermal expansion of a silicon wafer or the like, the contact position with the probe does not shift at high temperatures. Further, since the thermal conductivity is large, temperature matching is fast, and it is possible to quickly follow the temperature change of the silicon wafer.

FIG. 2 shows the probe card 40 in which the conductor circuit is formed on the surface of the ceramic substrate 41, but the conductor circuit may be formed inside the ceramic substrate. FIG. 3A is a cross-sectional view schematically showing a probe card in which such a conductor circuit is formed,
(B) is a plan view thereof.

In this probe card 70, the bottom surface 71b
2 and a through hole 72a extending from the bottom surface 71b to the middle of the ceramic substrate 71 is formed in a horizontal direction from the top of the through hole 72a. The pitch is increased by forming the conductor circuit 74 having a pattern substantially similar to the pattern shown in b). Then, a through hole 72b formed so as to be connected to the end of the conductor circuit 74 further reaches the upper surface 71a, and FIG.
The pattern of the terminal pad 75 is as shown in FIG.

Therefore, by using the probe card 70, the terminal pads having a relatively wide pitch formed on the performance board 24 and the terminal pads formed on the silicon wafer 60 are formed similarly to the case of the probe card 40 shown in FIG. The connection with the narrow-pitch terminal pads can be reliably performed.

Next, the materials and characteristics of the ceramic substrate and the conductor circuit constituting the probe card 40 will be described in more detail.

As described above, the ceramic substrate is
The ceramic substrate is made of a non-oxide ceramic such as a nitride ceramic or a carbide ceramic, but the ceramic substrate may contain a sintering aid. As the sintering aid, for example,
Examples thereof include alkali metal oxides, alkaline earth metal oxides, and rare earth oxides. Among these sintering aids,
_{CaO, Y 2 O 3, Na} 2 O, Li 2 O, Rb 2 O are preferred. Their content is 0.1 to 20% by weight.
Is preferred. Further, it may contain alumina.

In the above non-oxide ceramic, 5% by weight
The following oxygen may be contained. If the amount of oxygen is about 5% by weight, sintering can be promoted, withstand voltage can be secured, and the amount of warpage at high temperatures can be reduced.

The dose of α emitted from the surface of the non-oxide ceramic is desirably 50 c / cm ² · hr or less;
The optimum is 2.0 c / cm ² · hr or less. 50c / c
This is because when the value exceeds m ² · hr, a so-called soft error occurs and an error occurs in the inspection.

In the above ceramic substrate, the JIS
The surface roughness Rmax based on B0601 is 0.01 μm
<Rmax <100 μm is desirable.
Is preferably 0.001 <Ra <10 μm.

The ceramic substrate has a surface roughness of JI.
It is most preferable that SB0601Ra = 0.01 to 10 μm. Larger is better considering the adhesion of the surface to the conductor circuit. However, if it is too large, the measurement at high frequency may occur due to the skin effect (high-frequency signal current is localized and flows on the surface of the conductor circuit). This is because it is difficult, and when it is small, a problem occurs in adhesion.

The shape of the ceramic substrate is not particularly limited, but is preferably a square, a polygon, or a disk, and its diameter,
The length of the longest diagonal is preferably from 10 to 350 mm. The thickness of the ceramic substrate is preferably 50 mm or less,
mm or less is more preferable. If the thickness of the ceramic substrate is too large, the size of the device cannot be reduced, and the heat capacity increases, the temperature rising / falling rate decreases, and the temperature matching characteristics deteriorate. Further, by reducing the thickness of the ceramic substrate, the electrical resistance of the probe card can be reduced, and the occurrence of erroneous determination can be prevented.

The flatness of the ceramic substrate is -10 m in diameter.
m or 5 at the measuring distance of the longest diagonal length-10 mm
It is preferably not more than 00 μm. If the thickness exceeds 500 μm, warpage cannot be corrected even by pressing during measurement.

The thermal conductivity κ of the ceramic substrate is 10
W / m · k <κ <300 W / m · k is preferable, and 160
-220 W / mk is more preferable. By increasing the thermal conductivity, the rate of temperature rise / fall is increased, and the temperature matching is improved.

The Young's modulus E of the ceramic substrate is 25 to 6
It is desirable that 60 GPa <E <450 GPa at 00 ° C. This is for preventing the warpage of the ceramic substrate at a high temperature. The bending strength σ _f of the ceramic substrate is 25-600 ° C
And 200 MPa <σ _f <500 MPa is desirable. This is to prevent the ceramic substrate from being damaged during pressing. In addition, at the time of pressing, 0.1 to 1
A pressure of about 0 kg / cm ² is applied.

When pores are present inside the ceramic substrate, the pores are preferably closed pores. The amount of helium passing through the ceramic substrate (helium leak amount) is desirably 10 ⁻⁷ Pa · m ³ / sec or less. This is because the use of a dense ceramic substrate having a small amount of helice leakage can prevent through holes and the like formed therein from being corroded by oxygen and the like in the air.

The variation in the thickness of the ceramic substrate is ± 3.
% Is preferable. This is because the surface of the ceramic substrate needs to be flat in order to eliminate contact failure of the contactor substrate with the probe.

The variation in the thermal conductivity is preferably within ± 10%. This is because it is possible to prevent warpage or the like due to uneven temperature or the like.

The volume resistivity ρ of the ceramic substrate is 10 ¹³
It is desirable that Ω · cm <ρ <10 ¹⁶ Ω · cm.
This is to prevent generation of a leak current at a high temperature and dielectric breakdown between through holes.

The ceramic substrate has a brightness of JIS Z
It is desirable that the value based on the rule of 8721 is N4 or less. This is because a material having such lightness has a good appearance because it has concealing properties, has a large amount of radiant heat, and rapidly rises in temperature.

Here, the lightness N is defined as 0 for an ideal black lightness, 10 for an ideal white lightness, and the brightness of the color between these black lightness and white lightness. Each color is divided into ten so that the perception of the color is equal, and displayed by symbols N0 to N10. And the actual measurement is N0-N
The comparison is made with the color chart corresponding to No. 10. In this case, the first decimal place is 0 or 5.

The ceramic substrate having such characteristics has a carbon content of 100 to 5000 p in the ceramic substrate.
pm. There are two types of carbon, amorphous and crystalline.Amorphous carbon can suppress a decrease in volume resistivity of a ceramic substrate at a high temperature. Since the decrease in thermal conductivity at high temperatures can be suppressed, the type of carbon can be appropriately selected according to the purpose of the substrate to be manufactured.

The amorphous carbon is, for example, C, H, O
Hydrocarbons, preferably saccharides, can be obtained by calcining in air, and graphite powder can be used as the crystalline carbon.
In addition, carbon can be obtained by thermally decomposing the acrylic resin under an inert atmosphere and then heating and pressurizing. However, by changing the acid value of the acrylic resin, it is possible to obtain a crystalline (non-crystalline) material. Can be adjusted.

In the present invention, as shown in FIGS. 2 and 3, through-holes and conductor circuits are formed inside the ceramic substrate. These through-holes and conductor circuits are made of high melting point metal such as tungsten or molybdenum. , And a conductive ceramic such as tungsten carbide and molybdenum carbide.

The diameter of the through hole is 0.1 to 10 mm
Is desirable. This is because cracks and distortion can be prevented while preventing disconnection. The shape of the through hole is not particularly limited, and examples thereof include a columnar shape and a prismatic shape (square column, column, etc.).

Also, on the surface of the ceramic substrate, a conductor circuit for expanding the wiring pitch, and terminal pads for connecting to a probe substrate disposed above and a contactor substrate disposed below. Need to be formed,
These through holes, conductor circuits, terminal pads, and the like are usually desirably made of a high melting point metal such as tungsten or molybdenum, or a conductive ceramic such as tungsten carbide or molybdenum carbide.

However, depending on the case, these conductor layers may be made of a noble metal such as gold, silver or platinum or a metal such as nickel. The volume resistivity of these through holes, conductor circuits, terminal pads, etc. is 1 to 50 μΩ · cm.
Is preferred. If the sheet resistivity exceeds 50 μΩ, the inspection apparatus may make an erroneous determination due to heat generation in the through holes and the like.

In order to form through holes and conductive circuits on the surface or inside of the ceramic substrate, it is preferable to use a conductive paste made of metal or conductive ceramic. That is, when forming a through-hole or a conductor circuit inside a ceramic substrate, the through-hole formed in the green sheet is filled with a conductor paste, or the above-described green sheet is formed after the conductor paste layer is formed on the green sheet. By laminating and firing, through holes and conductive circuits are formed inside.

Further, by forming and firing a conductive paste layer on the uppermost or lowermost green sheet, conductive circuits and terminal pads can be formed on the surface of the ceramic substrate.

On the other hand, after the ceramic substrate is manufactured, the conductive paste layer is formed on the surface of the ceramic substrate, and the resultant is baked to form the conductive circuit and the terminal pads.
Further, the terminal pads may be formed by plating, sputtering, or the like.

The conductive paste is not particularly limited, but preferably contains a resin, a solvent, a thickener, etc. in addition to metal particles or conductive ceramic particles in order to secure conductivity.

Examples of the material of the metal particles and the conductive ceramic particles include those described above. The particle size of these metal particles or conductive ceramic particles is 0.1 to 10
0 μm is preferred. If it is too fine, less than 0.1 μm, it is liable to be oxidized, while if it exceeds 100 μm, sintering becomes difficult and the resistance value becomes large.

Although the shape of the metal particles is spherical,
It may be scaly. When these metal particles are used, they may be a mixture of the above-mentioned spheres and the above-mentioned flakes. When the metal particles are scaly, or a mixture of a spherical and scaly, it is easy to hold the metal oxide between the metal particles, and the adhesion between the conductor circuit and the ceramic substrate is ensured. This is advantageous.

Examples of the resin used for the conductor paste include an epoxy resin and a phenol resin. Examples of the solvent include isopropyl alcohol. Examples of the thickener include cellulose and the like.

When the conductor paste layer is formed on the surface of the ceramic substrate, a metal oxide is added to the conductor paste in addition to the metal particles, and the metal particles and the metal oxide are sintered. It is preferable that Thus, by sintering the metal oxide together with the metal particles, the ceramic substrate and the metal particles can be more closely adhered.

It is not clear why mixing the above metal oxide improves the adhesion to the ceramic substrate. However, the surface of the metal substrate or the surface of the ceramic substrate made of non-oxide has a slight surface. It is considered that the oxide film is oxidized to form an oxide film, and the oxide films are sintered and integrated via the metal oxide, so that the metal particles and the ceramic adhere to each other. Further, when the ceramic constituting the ceramic substrate is an oxide, the surface is naturally made of an oxide, so that a conductor layer having excellent adhesion is formed.

As the metal oxide, for example, oxidized
Lead, zinc oxide, silica, boron oxide (B _Two O_Three ), Al
Selected from the group consisting of Mina, Yttria and Titania
At least one is preferred. These oxides are metal
It can improve the adhesion between particles and ceramic substrate.
Because it can.

The ratio of the above-mentioned lead oxide, zinc oxide, silica, boron oxide (B ₂ O ₃ ), alumina, yttria, and titania is as follows: 1-10, silica 1-30, boron oxide 5-50, zinc oxide 20-70, alumina 1
-10, yttria 1-50, titania 1-50, and the total is preferably adjusted so as not to exceed 100 parts by weight. By adjusting the amounts of these oxides in these ranges, the adhesion to the ceramic substrate can be particularly improved.

In the present invention, a conductor circuit may be formed on at least one surface of the above-described ceramic substrate via a resin layer. By interposing the resin layer, it is possible to follow the pressure at the time of inspection, and it is less likely to be damaged than ceramic. Further, since the resin can lead the fine wiring, a high-density probe card can be obtained. Further, the resin has a smaller dielectric constant than the ceramic and has no propagation delay.

A through hole may be formed in the ceramic substrate, and a conductor circuit may be formed. There may be two or more resin layers, in which case the conductor circuits on each resin layer are connected by via holes.

As the resin, at least one selected from epoxy resins, polyimide resins and bismaleimide-triazine resins can be used. Further, it is desirable that the resin is sensitized. This is because the opening can be formed by photolithography. The thickness of the resin layer is 5-1
00 μm is desirable. This is to ensure insulation at high temperatures.

Next, a method for manufacturing the probe card of the present invention (method A) will be described with reference to FIG. (1) Green Sheet Manufacturing Step First, a paste is prepared by mixing a powder of a nitride ceramic or a carbide ceramic with a binder, a solvent, or the like, and a green sheet is manufactured using the paste. As the above-mentioned ceramic powder, aluminum nitride or the like can be used. If necessary, a sintering aid such as yttria may be added, or the surface thereof may be oxidized. Further, when producing a green sheet, crystalline or amorphous carbon may be added. By adding a sintering aid or oxidizing the surface, sintering proceeds during firing and a ceramic substrate having a small porosity can be obtained.

The binder is preferably at least one selected from an acrylic binder, ethyl cellulose, butyl cellosolve, and polyvinyl alcohol.
Further, as the solvent, at least one selected from α-terpineol and glycol is desirable.

The paste obtained by mixing them is formed into a sheet by a doctor blade method to form a green sheet 4.
00 is produced. The thickness of the green sheet 400 is 0.
1-5 mm is preferred. Next, a portion to be a through hole for forming a through hole is formed in the obtained green sheet as necessary. The above processing may be performed after forming a green sheet laminate described later.

(2) Step of Printing Conductor Paste on Green Sheet The above-described conductor paste is used on the uppermost green sheet 400 and the lowermost green sheet.
Conductive paste layers 430 and 440 made of conductive paste are formed. In addition, a portion serving as a through hole is filled with a conductive paste to form a filling layer 420.

When a conductor circuit is formed inside, a conductor paste layer may be formed on a green sheet serving as an inner layer. These conductive pastes contain metal particles or conductive ceramic particles. Examples of the material of the metal particles include, for example, tungsten or molybdenum, and examples of the conductive ceramic include:
Tungsten carbide or molybdenum carbide is used.

The average particle diameter of the metal particles such as tungsten particles or molybdenum particles is preferably 0.1 to 5 μm. Average particles less than 0.1 μm or 5 μm
This is because when the value exceeds the above, it is difficult to print the conductor paste.

As such a conductive paste, for example, 85 to 87 parts by weight of metal particles or conductive ceramic particles; 1.5 to 10 parts by weight of at least one kind of binder selected from acrylic, ethyl cellulose, butyl cellosolve, and polyvinyl alcohol And a composition (paste) obtained by mixing 1.5 to 10 parts by weight of at least one solvent selected from α-terpineol and glycol.

(3) Green Sheet Laminating Step The green sheet 4 having only the filling layer 420 between the green sheet 400 as the uppermost layer and the green sheet as the lowermost layer having the conductive paste layers 430, 440, etc.
00 are laminated and pressure-bonded to produce a laminate (see FIG. 4).

(4) Green Sheet Laminate Firing Step Next, the green sheet laminate is heated and pressurized to sinter the green sheet 400 and the internal and external conductor paste, thereby forming a ceramic having through holes 42 and the like. Substrate 4
1 (see FIG. 2). Heating temperature is 1000-2
000 ° C. is preferable, and the pressure for pressurization is 10 to 20 MPa
Is preferred. Heating is performed in an inert gas atmosphere. As the inert gas, for example, argon, nitrogen, or the like can be used. If the pressure applied during sintering is low, sintering does not easily proceed, and a ceramic substrate having a high porosity is produced.

The obtained ceramic substrate 41 is processed if necessary, and the manufacture of the probe card is completed. When a conductor circuit is provided inside a ceramic substrate, a conductor paste layer may be formed on a green sheet, and another green sheet may be laminated above and below the green sheet, and then fired. When a conductor layer is formed on the surface of a ceramic substrate, the conductor layer may be formed by using a sputtering method or a plating method after manufacturing the ceramic substrate.

In addition to the above manufacturing method, the following manufacturing method (manufacturing method B) may be adopted. (1) A slurry is prepared by mixing a sintering aid such as yttria, a binder, and the like with the above-mentioned nitride ceramic or carbide ceramic powder, if necessary, and then the slurry is granulated by a method such as spray drying. Into a shape such as a plate by pressing the granules in a mold or the like,
A green form is produced. Next, the generated feature is changed to 6
Calcination is performed at a temperature of 00 to 1600 ° C., and a through hole to be a through hole is formed by a drill or the like.

(2) Step of Printing Conductive Paste on Substrate The conductive paste is generally a high-viscosity fluid composed of metal particles or conductive paste or a mixture thereof, a resin, and a solvent. This conductor paste is printed on conductor circuits and through-hole portions by screen printing or the like to form conductor paste layers and through-holes. The conductor circuit may be formed after the sintering step (3) described below is completed. (3) Next, the calcined body is heated, fired and sintered to produce a ceramic plate. Thereafter, the substrate is fabricated by processing into a predetermined shape, but may be a shape that can be used as it is after firing. By performing heating and baking while applying pressure, a substrate without pores can be manufactured. Heating and firing may be performed at a temperature equal to or higher than the sintering temperature. For a nitride ceramic or a carbide ceramic, the temperature is 1000 to 2500C.

Further, a case where a conductor circuit is formed on a ceramic substrate via a resin layer will be described. (1) First, a ceramic substrate is manufactured. This ceramic substrate may have a through-hole formed therein, or may have a conductive circuit formed on the surface or inside. Such a ceramic substrate can be manufactured by the methods A and B. The following description is based on the case where a through hole is formed on the surface obtained by the manufacturing method A.

(2) A conductor layer is provided on both surfaces of the obtained ceramic substrate by sputtering, plating, or the like with a metal such as titanium, molybdenum, nickel, or chromium, and an etching resist is formed by photolithography. Next, a part of the conductor layer is dissolved with an etching solution,
The etching resist is peeled off to form a conductor circuit. The thickness of the conductor circuit is preferably 1 to 10 μm. On the conductor circuit surface on the side where the resin layer is not formed, by electroless plating,
A non-oxidizable metal layer such as a nickel or noble metal (gold, platinum, silver, palladium) layer is provided. The thickness of the non-oxidizable metal layer is preferably 1 to 10 μm.

(3) Form a resin layer on at least one surface. The resin is preferably a photosensitive resin, and is preferably an acrylated epoxy resin or an acrylated polyimide resin. The resin layer may be formed by laminating a resin film or by spin-coating a liquid resin.

(4) After forming the resin layer, it is heated and dried, and then exposed and developed to form an opening. Further, the resin liquid is spin-coated again, dried by heating, and then exposed and developed to form an opening. The reason why one interlayer resin insulating layer is formed twice in this way is that even if a pinhole is formed in one of the resin layers, the other resin layer can ensure insulation. It is. Note that a resin may be filled between the conductor circuits formed on the surface of the ceramic substrate so as to eliminate unevenness due to the conductor circuits and to flatten them. Further, the opening may be provided by laser light.

(5) Next, the surface of the resin layer is modified by an oxygen plasma treatment or the like. Since a hydroxyl group is formed on the surface, adhesion to a metal is improved. Then chrome,
Perform sputtering of copper or the like. The thickness of the sputtering layer is preferably from 0.1 to 5 μm. Next, a plating resist is formed by photolithography, and Cu and Ni layers are formed by electrolytic plating. The thickness is desirably 2 to 10 μm. Thereafter, by removing the plating resist and performing etching, the portion where the conductor layer is formed is melted only by sputtering to form a conductor circuit. Thereafter, by repeating the above steps (3) to (5), a probe card in which a plurality of layers of resin and conductive circuits are formed on a ceramic substrate is manufactured. When forming a conductor circuit and a resin layer on a ceramic substrate,
The conductor circuit (resin layer) to be formed may be a single layer,
It may have two or more layers.

As described above, the probe card of the present invention may have a conductor circuit formed only on one main surface and have no through hole. In this case, after the ceramic substrate is manufactured, a conductor circuit and a pad may be formed on one main surface by a method of forming a conductor circuit using the above-described conductor paste, a sputtering method, a plating method, or the like. In this case, for example, if an insulating film is formed on the surface,
Even if the ceramic substrate itself has a certain degree of conductivity, it can be used as a probe card.

The probe card having such a configuration is used, for example, in an inspection apparatus as shown in FIG. That is, in this inspection apparatus, the silicon wafer 60 is mounted on the performance substrate 24, and further, the contactor substrate 50 and the probe card 40 are mounted thereon, and the probe card 40 and the silicon wafer are mounted via the contactor substrate 50. The connection with 60 is made.

The connection between the performance board 24 and the probe card 40 is made via the probe board 30, and pads (not shown) on the silicon wafer 60 are provided.
Are connected to the pads of the performance board 24 via the contactor board 50-the conductor circuit formed on the probe card 40-the probe board 30.

[0094]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Examples 1 to 7) Production of probe card (see FIGS. 2 and 4) (1) 100 parts by weight of aluminum nitride powder (manufactured by Tokuyama Corporation, average particle size: 1.1 μm), yttria (Y ₂ O)
₃ , average particle size: 0.4 μm) A doctor was prepared by using a paste obtained by mixing 4 parts by weight of an acrylic binder, 11.5 parts by weight of an acrylic binder, 0.5 parts by weight of a dispersant, and 53 parts by weight of alcohol composed of 1-butanol and ethanol. The green sheet 400 having a thickness of 0.47 mm is formed by a blade method.
Was prepared.

(2) Next, the green sheet 400 was dried at 80 ° C. for 5 hours, and a through-hole or the like serving as a through-hole 58 was formed by punching.

(3) 100 parts by weight of tungsten carbide particles having an average particle diameter of 1 μm, acrylic binder 3.0
By weight, 3.5 parts by weight of the α-terpineol solvent and 0.3 parts by weight of the dispersant were mixed to prepare a conductor paste A.

Tungsten particles 10 having an average particle size of 3 μm
A conductive paste B was prepared by mixing 0 parts by weight, 1.9 parts by weight of an acrylic binder, 3.7 parts by weight of an α-terpineol solvent, and 0.2 parts by weight of a dispersant.

This conductor paste A is printed on the green sheet as the uppermost layer and the lowermost layer by screen printing, and the conductor paste layer 440 for the conductor circuit 44 and the terminal pad 45 is printed.
Was formed. The printing pattern was a pattern as shown in FIG. 2, and the width of the conductive paste layer was 75 μm and its thickness was 3 μm. Further, a conductive paste B was filled into a portion to be a through hole to form a filling layer 420.

Between the two green sheets 400 after the above treatment, 25 green sheets 400 each having only the filling layer 420 were laminated at 130 ° C. and a pressure of 8 MPa, and pressed.

(4) Next, the obtained laminate was degreased in nitrogen gas at 600 ° C. for 5 hours, and hot-pressed at a temperature of 1890 ° C. for 3 hours at a pressure shown in Table 1 to obtain a laminate having a thickness of 5 mm. An aluminum nitride sintered body was obtained. One side is 60m
Then, the production of the probe card 40 having a cylindrical through hole 42 having a diameter of 200 μm, a conductor circuit 44 having a thickness of 3 μm and a width of 75 μm, and a terminal pad 43 of 500 μm square was completed.

Example 8 Manufacture of Probe Card (See FIG. 2) (1) 100 parts by weight of aluminum nitride powder (manufactured by Tokuyama Co., average particle size 1.1 μm), yttria (Y ₂ O ₃ average particle size of 0.1%). 4 μm) A composition comprising 4 parts by weight, 12 parts by weight of an acrylic resin binder and alcohol was spray-dried to prepare a granular powder.

(2) Next, this granular powder was put into a mold and molded into a flat plate to obtain a formed product (green). The formed body was calcined at 1400 ° C., and a through-hole for a through hole 42 was formed in the processed body by a drill, and the inside thereof was filled with the conductive paste B used in Example 1.

(3) One side of the molded body after the above process is
A 60 mm square was cut out to form a ceramic plate (ceramic substrate 41).

(4) Next, 100 parts by weight of tungsten carbide particles having an average particle diameter of 3 μm, 1.9 parts by weight of an acrylic binder, 3.7 parts by weight of an α-terpineol solvent, and 0.2 part by weight of a dispersant are mixed. Thus, a conductor paste C was prepared. Top surface 41a and bottom surface 4 of ceramic substrate 41
1b, a conductor paste layer for the conductor circuit 44 and the terminal pad 43 was formed by screen printing using the conductor paste C.

(5) Next, the substrate on which the conductor paste has been printed is hot-pressed at 1800 ° C. and 20 MPa to sinter tungsten, tungsten carbide, and the like in the conductor paste, and bake the sintered body on a sintered body to form a conductor circuit 44. And a cylindrical through hole 4 having a diameter of 200 μm inside.
2. The manufacture of the probe card 40 having the conductor circuit 44 having a thickness of 3 μm and the width of 75 μm and the terminal pad 43 of 500 μm square was completed.

Example 9 Production of Probe Card Having Polyimide Resin Layer (See FIG. 5) (1) 100 parts by weight of aluminum nitride powder (manufactured by Tokuyama Corporation, average particle size: 1.1 μm), alumina (Al ₂ O)
₃ , average particle diameter: 0.4 μm) A doctor mixed with 5 parts by weight of an acrylic binder, 11.5 parts by weight of a binder, 0.5 parts by weight of a dispersant, and 53 parts by weight of alcohol composed of 1-butanol and ethanol. The green sheet having a thickness of 0.47 mm was formed by molding using a blade method.

(2) Next, the green sheet is heated to 80 ° C.
After drying for 5 hours, a through hole or the like serving as a through hole was formed by punching. (3) Conductive paste B was prepared by mixing 100 parts by weight of tungsten particles having an average particle diameter of 3 μm, 1.9 parts by weight of an acrylic binder, 3.7 parts by weight of an α-terpineol solvent, and 0.2 parts by weight of a dispersant. . Further, a portion to be a through hole was filled with the conductive paste B to form a filling layer.

(4) Between the two green sheets after the above treatment, 25 green sheets having only a filling layer were laminated and pressed at 130 ° C. and a pressure of 8 MPa. (5) Next, the obtained laminate was degreased in a nitrogen gas at 600 ° C for 5 hours, and hot-pressed at 1890 ° C and a pressure of 15 MPa for 10 hours to obtain an aluminum nitride sintered body having a thickness of 5 mm. This was cut into a disk having a diameter of 100 mm to obtain a ceramic substrate 81 having a cylindrical through hole 82 having a diameter of 200 μm inside.

(6) On both surfaces of the ceramic substrate 81,
Sputtering equipment (CFS-RP-1 manufactured by Tokuda Seisakusho)
00) using 0.1 μm thick Ti and 2.0 μm M
o, Ni of 1.0 μm was sputtered in this order. Further, a resist was laminated, and then exposed and developed to obtain an etching resist. HF / HN at 55 ° C
Etching with O ₃ aqueous solution, Ti layer, Mo layer, Ni layer
A conductor circuit 83 composed of layers was formed.

(7) The ceramic substrate was heated at 120 ° C. for 30 minutes before coating. Next, a photosensitive polyimide (I-8802B manufactured by Asahi Kasei) was applied by a spin coater,
The resultant was dried by heating at 20 ° C. for 20 minutes, and then heated and cured at 350 ° C. to form a polyimide layer 84, which was smoothed without any unevenness between the conductor circuits.

(8) Further, a photosensitive polyimide (I-8802B manufactured by Asahi Kasei) was applied by a spin coater,
And dried by heating at 20 mJ for 20 minutes. A mask is laminated and exposed at 200 mJ.
MDG). Further, it was heated at 350 ° C., post-baked, and cured.

(9) The same processing as in step (8) is performed.
A second polyimide layer 85 having a thickness of 10 μm was formed. A via hole opening having a diameter of 100 μm was formed in the polyimide layer 85. (10) The surface of the polyimide layer was subjected to oxygen plasma treatment. Further, the surface was washed with 10% sulfuric acid.

(11) Next, a Cr layer having a thickness of 0.1 μm and a copper layer having a thickness of 0.5 μm were formed in this order by the above-mentioned sputtering apparatus. (12) Then, a resist film was laminated, exposed and developed to form a plating resist.

(13) Further, 80 g / l copper sulfate and 18 g
Electrolytic copper plating bath consisting of 0 g / l sulfuric acid and 100 g / l
Using an electrolytic nickel bath containing 1 l of nickel sulfamate, electrolytic plating was performed at a current density of 1 A / dm ² to form a conductor having a thickness of 5.5 μm of copper and a thickness of 1 μm of Ni.

(14) Further, the plating resist is removed,
Hydrochloric acid / water = 2/1 (40 ° C) aqueous solution for Cr and Cu layers
Remove and remove terminal pad 86a (50 μm square)
The conductor circuit 86 includes the conductor circuit 86b. (15) Mask the resin surface with a film coated with an adhesive.
And then nickel chloride 2.31 × 10^-2mol / l,
Sodium hypophosphite 2.84 × 10^-2mol / l,
Sodium enoate 1.55 × 10^-2mol / l
pH = 4.5 electroless nickel plating bath, gold cyanide
Li 7.61 x 10^-3mol / l, ammonium chloride
1.87 × 10^-1mol / l, sodium citrate
16 × 10 ^-1mol / l, sodium hypophosphite 1.7
0x10^-1mol / l using a gold plating bath.
Ni layer 830a having a thickness of 5 μm and a thickness of 0.03
A non-oxidizable metal film 830 made of a μm Au layer 830b is
Thus, a probe card 80 was obtained (see FIG. 5).

(Embodiment 10) As in Embodiment 2, except that
The following steps were changed. Instead of (1), SiC powder (average particle size 0.5 μm) 1
A composition comprising 00 parts by weight, B ₄ C: 0.5 parts by weight, an acrylic resin binder 12 parts by weight, and alcohol was spray-dried to prepare a granular powder.

Instead of (2), a granular powder was placed in a mold and formed into a flat plate to obtain a formed product (green). This green compact was pressure-sintered at 1900 ° C. and 20 MPa. Next, a glass paste (G-5177 manufactured by Shoei Chemical Industry Co., Ltd.) was applied to the surface, and baked at 700 ° C. to provide a coat layer having a thickness of 2 μm on the surface. After that, a conductor circuit was formed on one main surface in the same manner as in Example 2. In this embodiment, the probe card has no through hole.

Comparative Example 1 100 parts by weight of aluminum nitride powder (manufactured by Tokuyama Corporation, average particle size: 1.1 μm), 11.5 parts by weight of an acrylic binder, 0.5 part by weight of a dispersant, 1-butanol and ethanol Alcohol 5
A green sheet 400 having a thickness of 0.47 mm was prepared by using a paste mixed with 3 parts by weight by a doctor blade method. Thereafter, a probe card was manufactured in the same manner as in Example 1 except that no pressure was applied when firing the green sheet laminate.

The porosity, the pore diameter, and the porosity of the probe cards thus manufactured according to Examples 1 to 10 and Comparative Example 1 were
The amount of warpage, withstand voltage, strength, coefficient of thermal expansion, and thermal conductivity were measured by the following methods. The results are shown in Table 1 below.

[0121]Evaluation method  (1) Measurement of porosity From the ceramic substrate that constitutes the probe card,
Cut out the sample and determine the porosity by the Akimimedes method.
It was measured. Specifically, crush the cut sample into powder
Into an organic solvent or mercury to measure the volume.
The true specific gravity is measured from the weight of the powder measured in advance,
And the porosity was calculated from the apparent specific gravity.

(2) Measurement of maximum pore diameter The probe card is cut at several points in the vertical direction, and any 10 points of the cut portion are photographed with an electron microscope, the largest pore in the visual field is selected, and the largest pore is selected. The average value was taken as the pore diameter of the largest pore. (3) Measurement of Withstand Voltage A sample for measurement was cut out from the probe card, electrodes were formed on both main surfaces, a voltage was applied, and a voltage for dielectric breakdown was measured.

(4) Amount of warpage A load of 100 kg / cm ² was applied, and the amount of warpage was measured using a shape measuring instrument (Nanoway manufactured by Kyocera Corporation). (5) Coefficient of Thermal Expansion A sample for measurement was cut out from the probe card and heated, and the temperature of the sample and the dimensions at that temperature were measured with a micrometer to determine the coefficient of thermal expansion.

(6) Thermal conductivity a. Equipment used Rigaku laser flash method thermal constant measurement device LF / TCM-FA8510B b. Test conditions Temperature: normal temperature Atmosphere: vacuum c. Measurement method-Temperature detection in the specific heat measurement was performed by a thermocouple (platinel) bonded to the back surface of the sample with a silver paste. The room temperature specific heat measurement was further performed in a state where a light receiving plate (glassy carbon) was adhered to the upper surface of the sample via silicon grease, and the specific heat (Cp) of the sample was obtained by the following formula (5).

[0125]

(Equation 1)

[0126] In the above equation (1), delta O is input energy, [Delta] T is the saturation value of the temperature rise of the sample, Cp
_Gc is the specific heat of glassy carbon, W _Gc is the weight of glassy carbon, Cp _SG is the specific heat of silicon grease, W _SG is the weight of silicon grease, and W is the weight of the sample.

(7) Strength The strength was measured by cutting out a sample for measurement and then measuring it with an Instron universal tester (type 4507 load cell 500 kg).
f), in the air at a temperature of 25 to 1000 ° C., a crosshead speed of 0.5 mm / min, a span distance L = 30 mm,
Test specimen thickness = 3.06 mm, test specimen width = 4.03 m
m, and the three-point bending strength σ (kgf / mm ² ) was calculated using the following equation (2).

[0128]

(Equation 2)

In the above formula (2), P is the maximum load (kgf) when the test piece breaks, L is the distance between the lower supports (30 mm), and t is the thickness of the test piece. Sa (m
m) and w is the width (mm) of the test piece.

(8) Oxygen content After cutting out a sample for measurement from the probe card,
Pulverized with a tungsten mortar, and 0.01 g of the sample was collected and subjected to a simultaneous oxygen / nitrogen analyzer (TC-1 manufactured by LECO) under the conditions of a material heating temperature of 2200 ° C. and a heating time of 30 seconds.
36 type).

[0131]

[Table 1]

As a result, in the probe cards of Examples 1 to 10, since the porosity of the ceramic substrate was 5% or less and the maximum pore diameter was 50 μm or less, the bending strength was large, the amount of warpage was small, and the coefficient of thermal expansion was small. Was close to a silicon wafer and the thermal conductivity was high. On the other hand, in the probe card of Comparative Example 1, the bending strength was small, the amount of warpage was large, and the thermal conductivity was low.

Further, the probe cards according to Examples 1 to 10 and Comparative Example 1 were set in the inspection apparatus shown in FIG. 1, and 100 silicon wafers which were found to be acceptable in advance were used. After the temperature was raised to 130 ° C., the operation state of the circuit was inspected.

In the inspection apparatus using the probe card according to Examples 1 to 10, all products were judged to be acceptable after 100 inspections, but the probe card according to Comparative Example 1 was 40%. The product was judged to be a rejected product, and it was found that at high temperatures, there was a high probability that the inspection device would make a wrong decision. Further, when observed with a thermoviewer at 130 ° C., the difference between the maximum temperature and the minimum temperature was within 0.5 ° C. in the probe cards of Examples 1 to 10, but was 5 ° C. in Comparative Example 1. Was. It is estimated that such a magnitude of the temperature distribution appears as a test error.

When the probe card according to Comparative Example 1 was observed at a high temperature, the probe card itself was warped or deformed, and the probe on the contactor substrate 50 and the terminal pad 43 of the probe card were deformed.
It was found that a problem was likely to occur in contact with the object.

[0136]

As described above, according to the present invention, the probe card is made of a ceramic substrate made of a non-oxide ceramic, and the porosity of the ceramic substrate is 0 or 5% or less. Excellent, does not warp or deform even at high temperatures, and does not cause poor contact with the probe. Also,
The withstand voltage of the ceramic substrate can be kept high, and dielectric breakdown between the through holes hardly occurs. Further, since the ceramic substrate has a high thermal conductivity, temperature matching is fast, and the ceramic substrate can quickly follow a temperature change of the silicon wafer.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of an inspection device using a probe card of the present invention.

FIG. 2A is a cross-sectional view schematically illustrating an example of a probe card, and FIG. 2B is a plan view thereof.

FIG. 3A is a cross-sectional view schematically showing another example of the probe card, and FIG. 3B is a plan view thereof.

FIG. 4 is a cross-sectional view schematically showing a green sheet laminating step in manufacturing a probe card.

FIG. 5 is a cross-sectional view schematically showing a probe card having a resin layer.

FIG. 6 is a sectional view showing a configuration of another inspection apparatus using the probe card of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Inspection apparatus 20 Tester 22 Heating device 24 Performance board 28 Heater 29 Cooling device 30 Probe 40, 70 Probe card 41, 71 Ceramic substrate 41a, 71a Top surface 41b, 71b Bottom surface 42, 72a, 72b, 76 Through hole 43, 45, 73, 75 Terminal pad 44, 74 Conductor circuit 50 Contactor substrate 60 Silicon wafer

Claims (4)

[Claims] 1. A probe card used for inspecting a circuit formed on a semiconductor wafer, wherein the probe card is made of a non-oxide ceramic ceramic substrate, and the porosity of the ceramic substrate is 0 or 5%. A probe card characterized by the following. 2. The probe card according to claim 1, wherein the pore diameter of the largest pore of the ceramic substrate is 50 μm or less. 3. The probe card according to claim 1, wherein the ceramic substrate has at least a through hole provided therein. 4. The probe card according to claim 1, wherein the ceramic substrate has a conductor circuit formed on one main surface.