JPH0794848A - Method for forming conductor layer pattern - Google Patents

Abstract

(57) [Summary] [Structure] A positive photoresist layer 12 is formed on a ceramic substrate 11, and the positive photoresist layer 12 is exposed and developed through a photomask 13,
After forming the concave portion 15 in the conductor layer forming pattern on the positive photoresist layer 12, the positive photoresist layer 12 is formed.
Is exposed to the entire surface, and the conductive paste 16 is filled in the concave portion 15 by a screen printing method using a screen 17 having the same pattern as the conductive layer forming pattern. The method for forming a conductor layer pattern in which the solid component of (1) is adhered to the ceramic substrate 11, the positive photoresist layer 12 is made to disappear by a development process, and the solid component in the conductor paste 16 is baked on the ceramic substrate 11 by firing. [Effect] It is possible to inexpensively manufacture a pattern of the conductor layer 19 having an accurate and fine shape and reliably insulating between the conductor layers 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a conductor layer pattern, and more particularly to a method for forming a fine conductor layer pattern for mounting semiconductor LSIs, chip parts, etc., or interconnecting them.

[0002]

2. Description of the Related Art In recent years, electronic devices have become smaller and higher in density, and electronic components mounted on these electronic devices have been rapidly made to have a narrower pitch and a larger number of pins, and have a multi-chip structure. Therefore, as a bonding method for LSIs and IC chips, a TAB (Tape Automated Bonding) method or a flip chip method suitable for multi-chip and high-density mounting has been adopted from the conventional wire bonding method. With the increasing density of such electronic devices, there has been a demand for a technique for forming a fine wiring having a line width of 100 μm or less and a conductor layer pattern such as a bump having a diameter of 100 μm or less on a ceramic wiring substrate. ing. Hereinafter, a method of forming a wiring pattern on a ceramic substrate will be described as an example.

Conventional methods for forming a wiring pattern on a ceramic substrate are roughly classified into a thin film method, a plating method, a thick film method and the like.

In the thin film method, vapor deposition on a ceramic substrate,
This is a method of forming a conductor metal layer having a thickness of several μm order by sputtering or ion plating. In this method, a photolithography technique using a photoresist can be used, so that highly precise fine wiring can be formed. Although it is possible, there are problems that the adhesion between the formed wiring and the substrate is low, the number of steps is larger than other methods, and the thin film forming apparatus is expensive.

Further, the plating method is a method of forming a conductor wiring on a ceramic substrate by an electrochemical method in a solution, but it has substantially the same problems as the above-mentioned thin film method.

Further, in the thick film method, a conductor paste in which conductor particles are dispersed in an organic vehicle containing a liquid component such as a solvent is used, and the conductor paste is printed on a ceramic substrate through a mesh screen and then fired. Is a method of forming a wiring pattern on a ceramics substrate. When the wiring pattern is formed by applying the thick film method, it is not always necessary to use a sintered body as the substrate, and after forming the pattern of the conductor paste on the green sheet, baking the green sheet and baking the conductor paste. May be performed at the same time.

The thick film method has an excellent feature that a conductor layer pattern having sufficient adhesion strength with a ceramic substrate can be formed at low cost. Further, when this method is applied to the method for forming a wiring pattern using the above-mentioned green sheet, the liquid component in the printed conductor paste is well absorbed inside the green sheet in a short time. It is also possible to form a fine wiring pattern having a distance of 150 μm or less. However, when this method is applied to a method of forming wiring on a sintered body, the liquid component is not absorbed inside the sintered body.
The liquid component in the printed conductor paste spreads laterally, so-called "bleeding" or "sagging" occurs, and the conductor layer pattern with the width of the wiring and the distance between the wirings of 150 μm or less is formed as designed. There was a problem that I could not do it.

Therefore, in recent years, photolithography using a photoresist, which is a feature of the thin film method, is introduced to form a wiring pattern, and a method using a conductor paste, which is a feature of the thick film method, is used to form the wiring itself. Being tried.

In this method, first, a photoresist layer is formed on the surface of a glass substrate or a ceramic substrate, and then a groove portion is formed in the photoresist layer in a wiring pattern shape by photolithography, and a conductor paste is rubbed into the groove portion. Is a method of simultaneously performing decomposition and disappearance of the photoresist layer and baking of the conductor component on the substrate by filling the same with the above and then baking it (JP-A-4-223391).
Japanese Patent Application Laid-Open No. 4-223392, Japanese Patent Application Laid-Open No. 4-2
23393 publication).

[0010]

In this method, since the conductor paste conventionally used in the thick film method can be used, the conductivity of the wiring itself is good, but the above-mentioned layer formed in the photoresist layer is used. In the step of rubbing the conductor paste into the groove portion, it is difficult to completely remove the thin layer of the conductor paste deposited on the surface of the photoresist layer other than the groove portion. Since it remains on the surface, there is a problem that the wiring may be short-circuited after firing.

It is possible to polish and remove the layer of the conductor paste by using a wrapping film, but since the number of steps increases and it is difficult to uniformly polish, the wiring layer to be formed has irregularities. The problem of being easy remains.

Further, in the baking step, since it is necessary to heat the photoresist layer to 900 ° C. or higher in an oxidizing atmosphere in order to completely decompose and disappear the photoresist layer, there is a problem that the conductor material is oxidized. there were.

The present invention has been made in view of the above problems, and is a method for inexpensively forming a highly precise and fine conductor layer pattern in which the conductor layers to be formed are not oxidized and the conductor layers are completely insulated. Is intended to provide.

[0014]

In order to achieve the above object, a method for forming a conductor layer pattern according to the present invention comprises a photoresist layer forming step of forming a positive type photoresist layer on a ceramic substrate, and the positive type By subjecting the photoresist layer to an exposure process through a photomask having a predetermined conductor layer forming pattern, and then performing a developing process,
A concave portion forming step of forming a concave portion in the conductor layer forming pattern on the positive photoresist layer; a whole surface exposure processing step of subjecting the positive photoresist layer having the concave portion to a whole surface exposure treatment; Using a screen having the same pattern as the formation pattern, a conductor paste filling step of filling a conductor paste in the recess by screen printing, and drying the conductor paste filled in the recess, a solid component in the conductor paste A step of adhering the positive type photoresist layer to the ceramics substrate, a step of developing the positive type photoresist layer to remove the positive type photoresist layer, and a solid component in the conductor paste by firing And a baking step of baking on a ceramics substrate.

A method of forming a conductor layer pattern according to the present invention will be described below with reference to FIGS. 1 (a) to 1 (g).

First, as a photoresist layer forming step, a positive type photoresist layer 12 is formed on the ceramic substrate 11 (FIG. 1A).

The ceramic substrate 11 used in the present invention is not particularly limited, and examples thereof include an alumina ceramic substrate usually used as a ceramic substrate, a mullite ceramic substrate, a glass ceramic substrate, an aluminum nitride ceramic substrate, and the like.

The method of forming the positive photoresist layer 12 is not particularly limited, and a method of forming the positive photoresist layer 12 by adhering a positive photoresist film to the ceramic substrate 11 may be used. However, a liquid positive photoresist is used, and after the liquid photoresist is applied on the ceramic substrate 11 by, for example, a roll coater method, a bar coater method, a spin coater method, a dip method or the like, an oven is used for 85 to 90
The method of forming the solid-state positive photoresist layer 12 by heat treatment at 30 ° C. for about 30 to 40 minutes and drying can form the horizontal positive photoresist layer 12,
It is more preferable since a flat conductor layer pattern can be finally formed. Examples of the liquid photoresist include AZ4903 and A manufactured by Hoechst Japan.
Z4620, OP resist manufactured by Tokyo Ohka Kogyo Co., Ltd., Accutrace manufactured by Tokyo Electron, Probimer manufactured by Ciba-Geigy Japan, and the like can be mentioned.

The thickness of the positive photoresist layer 12 formed is preferably 10 to 50 μm. When the thickness of the positive photoresist layer 12 is less than 10 μm, it becomes difficult to fill the concave portion 15 formed in the positive photoresist layer 12 with the conductive paste 16 in a later step, while the thickness of the positive photoresist layer 12 is reduced. When the thickness exceeds 50 μm, the conductor layer forming pattern-shaped recess 15 is formed in the case where development processing is performed in a later step.
Is difficult to form completely. In order to uniformly form the positive photoresist layer 12 of 10 μm to 50 μm on the ceramic substrate 11 using the liquid photoresist, the roll coater method or the bar coater method is more preferable among the coating methods.

When the positive photoresist layer 12 is formed by using a liquid photoresist, the ceramic substrate 11
Even if the surface has irregularities of the order of single micron, the surface of the formed positive photoresist layer 12 becomes flat.

Next, as a recess forming step, the positive photoresist layer 12 is exposed to ultraviolet rays 14 or the like through a photomask 13 having a predetermined conductor layer forming pattern (FIG. 1 (b)), and then developed. By applying
The recesses 15 are formed in the positive photoresist layer 12 in a conductor layer forming pattern (FIG. 1C). The poorly developed photoresist remaining in the recess 15 can be removed by dry etching such as plasma ashing.

The conditions of the exposure treatment with the ultraviolet rays 14 and the like are not particularly limited, and the exposure treatment can be performed under the conditions of the exposure treatment usually applied to the positive photoresist layer when forming a semiconductor substrate or the like. The conditions of the development treatment are not particularly limited, and the development can be performed by a commonly used method such as a spray method or an immersion rocking method.

The positive photoresist layer 1 is formed by the above method.
2, it is possible to form the recess 15 having a width or diameter of about 30 to 50 μm and a distance between the recesses of about 25 to 50 μm.

Next, in the entire surface exposure processing step, ultraviolet rays 1 are applied to the entire surface of the positive photoresist layer 12 in which the concave portions 15 are formed.
The entire surface is exposed by irradiating 4 or the like (FIG. 1D).

The purpose of subjecting the positive photoresist layer 12 to the entire surface exposure treatment is to perform a developing treatment in a later step,
This is for dissolving and eliminating this positive photoresist layer 12. The conditions of this exposure process are not particularly limited, and may be the conditions usually performed.

Next, in a conductor paste filling step, a screen 17 having the same pattern as the conductor layer forming pattern is used, and a conductor for forming a conductor pattern is formed in the concave portion 15 formed in the positive photoresist layer 12 by a screen printing method. The paste 16 is filled (FIG. 1E).

As the conductor for forming the conductor pattern, a known conductor material usually used for wiring of a substrate or the like can be used. Specific examples thereof include W and Mo-M.
n, Au, Ag-Pd, Cu, etc. are mentioned.

Further, as the solvent of the conductor paste 16, it is necessary to use a solvent that does not dissolve the positive photoresist layer 12. This is because when the conductor paste 16 is prepared using a solvent that dissolves the positive photoresist layer 12, when the conductor paste 16 is filled in the recess 15 of the positive photoresist layer 12, the photoresist layer 12 dissolves in the solvent. However, this is because the shape of the recess 15 collapses. Examples of the solvent that does not dissolve the positive photoresist layer 12 include hydrocarbon solvents having a low dielectric constant such as toluene, xylene, camphor oil, turpentine oil, and pine oil.

The resin (binder) used for the conductor paste 16 must be one that does not dissolve in the developing solution used in the subsequent step. This is because the residual solvent was left in the process of filling the concave portion 15 formed in the positive photoresist layer 12 with the conductor paste 16 and drying it, and then contacting this positive photoresist layer 12 with a developing solution to dissolve and eliminate it. This is to prevent the conductor paste 16 from being dissolved in the developing solution. Since the developing solution is usually an aqueous solution, the resin used for the conductor paste 16 needs to be a water-insoluble resin. Specific examples of the resin include ethyl cellulose, acrylic resin, methacrylic resin and the like.

For the above reasons, the conductor paste 16 used in the present invention contains, for example, 80 to 92 of the above conductor powder.
It is preferable that the composition has a composition including wt%, 2 to 6 wt% of the resin such as the acrylic resin, and 2 to 18 wt% of a solvent such as toluene. In addition, materials such as glass and ceramics for improving the adhesion to the substrate. May be added in a small amount.

In order to fill the concave portion 15 with the conductive paste 16 having the above composition, the conductive layer forming pattern formed on the screen 17 is aligned with the conductive pattern forming concave portion 15 formed on the positive photoresist layer 12. The conductor paste 16 may be discharged from the mesh of the screen by moving the squeegee 18 by applying a normal screen printing method. In order to match the conductor layer forming pattern formed on the screen 17 with the pattern of the concave portion 15 formed on the positive type photoresist layer 12, the position is determined by an ordinary image confirmation device equipped with a CCD camera, a monitor, a zoom lens and the like. Matching can be done.

As described above, since the above-mentioned screen printing method is applied in the present invention, the conductor paste 16 does not remain on the surface of the positive photoresist layer 12 other than the recessed portion 15, whereby the conductor layer 19 is formed. After forming
A phenomenon such as a short circuit between the conductor layers 19 does not occur, and the insulation between the conductor layers 19 can be maintained.

Next, in the bonding step, the conductor paste 16 filled in the recess 15 is dried to bond the solid component in the conductor paste 16 to the ceramic substrate 11.

In this step, the solvent component in the conductor paste 16 is evaporated, and at the same time, this heat treatment is performed to bond the solid component in the conductor paste 16 to the surface of the ceramic substrate 11 via the resin.

Then, as a photoresist layer disappearing step,
The positive photoresist layer 12 is developed to remove the photoresist layer 12 (FIG. 1 (f)).

Since the positive photoresist layer 12 has been subjected to the exposure treatment in the above-described whole surface exposure treatment step, the positive photoresist layer 12 is dissolved and disappears by performing the development treatment using the developing solution. To do. No special condition is required as the condition of the developing process. Further, since the water-insoluble resin is used as the solvent of the conductor paste 16, the conductor paste 1 formed in the conductor layer forming pattern is formed.
The shape of the dried body of 6 does not collapse.

In this case, if a method of removing the positive type photoresist layer 12 by burning it in an oxidizing atmosphere is used, a large amount of resin must be burned, so that
Harsh conditions are required, and thermal damage and oxidative damage to the ceramic substrate 11 and conductors are large, which is not preferable.

Finally, as a baking step, baking is performed to decompose and eliminate the organic components in the conductor paste 16 containing the conductor adhered to the ceramic substrate 11, and the conductor components in the conductor paste 16 are removed. To form a pattern of the conductor layer 19 (FIG. 1).
(G)).

The firing conditions in this case differ depending on the type of the ceramic substrate 11 and the type of the conductor material, but the organic substance contained in the conductor paste is sufficiently decomposed and disappears,
Furthermore, the condition that the conductor is firmly adhered to the ceramic substrate 11 is required.

Through the above steps, the pattern of the conductor layer 19 made of a conductor material can be formed on the ceramic substrate 11.

The conductor layer 19 is appropriately plated with Ni or A.
u plating may be applied, or Cr, Cu, or the like may be vapor-deposited.

The above-described method of forming a conductor pattern of the present invention can be applied to a method of forming fine wiring on a ceramic substrate, and is also connected by a flip chip method, for example, when an integrated circuit or the like is mounted on the ceramic substrate. It can also be used as a method for forming a bump used as a pad for a substrate on a ceramic substrate.

[0043]

According to the conductor pattern forming method having the above structure,
A photoresist layer forming step of forming a positive photoresist layer on a ceramic substrate, and an exposure process on the positive photoresist layer through a photomask having a predetermined conductor layer forming pattern, and then a developing process. A concave portion forming step of forming a concave portion on the positive photoresist layer in the conductor layer forming pattern, an overall exposure treatment step of subjecting the positive photoresist layer having the concave portion to an overall exposure treatment, Using a screen having the same pattern as the conductor layer forming pattern, a conductor paste filling step of filling the recess with a conductor paste by a screen printing method, and drying the conductor paste filled in the recess, A bonding step of bonding a solid component to the ceramic substrate, and the positive photoresist Since the photoresist layer disappearing step of applying a developing treatment to disappear the positive photoresist layer and a baking step of baking the solid component in the conductor paste onto the ceramic substrate by baking, the photoresist layer forming step And, in the recess forming step, a precise and fine conductor layer forming pattern recess is formed by photolithography, and in the conductor paste filling step, the conductor paste does not adhere to the photoresist layer surface other than the recess, and The pattern of the conductor paste filled in the recess is not broken or deformed. Through the subsequent bonding step, photoresist layer disappearing step, and baking step, a conductor layer pattern having an accurate and fine shape and insulating between the conductor layers can be manufactured at low cost.

Further, in the photoresist layer disappearing step,
By utilizing the characteristics of the positive type photoresist, the photoresist layer is erased by the developing process, and therefore, as compared with the conventional method of eliminating the photoresist layer by burning, it is possible to apply the same to the conductor layer and the substrate material. Reduces thermal and oxidative damage.

The whole surface exposure process may be performed after the conductor paste filling process or the bonding process. Also in this case, similarly to the above-described method of forming a conductor pattern of the present invention, a conductor layer pattern having an extremely fine shape is formed as compared with the conventional method.

[0046]

EXAMPLES AND COMPARATIVE EXAMPLES Examples and comparative examples of the method for forming a conductor layer pattern according to the present invention will be described below.

[Example 1] A liquid positive resist (manufactured by Hoechst Japan Co., Ltd.) was formed on the entire surface of an alumina ceramics substrate.
AZ4903) was applied by a bar coater method so as to have a film thickness of 25 μm, and this was put in an oven kept at 90 ° C. for 30 minutes to be dried to form a solid positive photoresist layer. .

Next, the positive photoresist layer is irradiated with ultraviolet rays at an exposure amount of 3000 mJ / cm ² through a photomask having a wiring pattern of a predetermined shape having a line width of 50 μm and a space between lines of 40 μm. did.

Next, a developing solution (AZ from Hoechst Japan Co., Ltd.
The alumina ceramics substrate having the positive photoresist layer was dipped in 400 K) and developed by rocking it to form grooves in the positive photoresist layer in the wiring pattern.

Next, the alumina ceramics substrate was placed on a hot plate kept at 120 ° C. and heated for 30 seconds, and then the entire surface of the positive type photoresist layer was irradiated with ultraviolet rays at an exposure dose of 3000 mJ / cm ^2. did.

Next, molybdenum powder having an average particle size of 1.0 μm: 75 parts by weight, manganese powder having an average particle size of 2.1 μm: 15 parts by weight, titanium oxide having an average particle size of 0.5 μm:
5 parts by weight and silica having an average particle diameter of 2.5 μm: 5 parts by weight of a conductor raw material powder was dispersed in 23 parts by weight of a printing oil (80810 manufactured by Degussa Japan Co., Ltd.) and the same as the above wiring pattern. The conductor paste was filled in the groove portions of the positive photoresist layer by screen printing through a screen having the pattern.

Specifically, first, the wiring pattern of the screen is matched with the wiring pattern of the groove formed in the positive photoresist layer, the conductor paste is placed on the screen, and the squeegee is moved. Then, the conductor paste is discharged from the mesh of the screen, and the groove portion of the positive photoresist layer is filled with the conductor paste. In the conductor paste filling step by this screen printing method, since the conductor paste does not adhere to the surface of the positive photoresist layer other than the groove portion, the conductor remains between the wirings after firing and short-circuits. There is nothing to do.

Next, the conductor paste filled in the groove is dried by heating at 90 ° C., and the resin component in the conductor paste is adhered to the alumina ceramic substrate.

Next, the alumina ceramics substrate that has undergone the above steps is subjected to a developing solution (AZ40 manufactured by Hoechst Japan KK).
Then, the positive photoresist layer was dissolved and disappeared, and only the dried body of the conductor paste was left on the alumina ceramic substrate.

Then, by firing at 1500 ° C. in a nitrogen-hydrogen mixed gas atmosphere containing a small amount of water vapor, organic substances in the conductor paste are decomposed and disappeared, and the conductor is baked on the alumina ceramics substrate to form wiring. A pattern was formed.

When the precision of the finally formed wiring was examined by a scanning electron microscope, the line width was 50 μm ± 2 μm, which was extremely high precision. Moreover, when it was examined by an optical microscope whether or not there was a short circuit between the wirings, there was no short circuit between the wirings.

[Example 2] The conductor component in the conductor paste was 95 parts by weight of copper powder having an average particle size of 1.5 to 2.0 µm and 5 parts by weight of glass powder having an average particle size of 0.7 to 1.5 µm. As a firing condition in the baking step, in a nitrogen atmosphere,
The same conditions as in Example 1 were adopted except that the condition of heating to 900 ° C. was selected, and copper fine wiring was formed on the alumina ceramics substrate.

When the precision of the wiring on the manufactured alumina ceramics substrate was investigated, the line width was 50 μm ± 2 μm, which was extremely high precision. Moreover, there was no short circuit between the wirings.

Example 3 A positive type having a thickness of about 25 μm was formed on an alumina ceramics substrate (surface roughness ± 3 μm) using a liquid positive type photoresist (AZ4903 manufactured by Hoechst Japan Ltd.) by a bar coater method. A photoresist-containing layer was formed and dried in the same manner as in Example 1 to form a solid positive photoresist layer.

Then, the positive photoresist layer is irradiated with ultraviolet rays through a photomask having a predetermined bump formation pattern (bump diameter: 50 μm, pitch between bumps: 100 μm) under an exposure amount of 3000 mJ / cm ^2. did.

Next, a developing solution (manufactured by Hoechst Japan
The alumina ceramics substrate having the positive photoresist layer was immersed in AZ400K) and shaken for development to form recesses in the positive photoresist layer in the bump formation pattern.

Next, the alumina ceramics substrate was placed on a hot plate kept at 120 ° C. and heated for 30 seconds, and then ultraviolet rays were applied to the entire surface of the positive photoresist layer under the condition that the exposure amount was 3000 mJ / cm ^2. did.

Next, Mo and Mn as conductor materials (average particle size is the same as in Example 1), and SiO as other additives.
₂ and TiO ₂ (the average particle size is the same as in Example 1), each containing 85 wt% of powder mixed in a ratio of 75: 15: 5: 5 (weight ratio), and 6 w of an acrylic resin.
Using a conductor paste containing t% and turpentine oil of 9 wt%, the conductor paste was filled in the recesses of the positive photoresist layer by the screen printing method as in Example 1.

Next, the conductor paste filled in the recess was dried by heating at 90 ° C., and the acrylic resin in the conductor paste was adhered to the alumina ceramic substrate.

Next, the alumina ceramics substrate that has undergone the above steps is subjected to a developing treatment in the same manner as in Example 1,
The positive photoresist layer was dissolved and disappeared, and only the dried body of the conductor paste was left on the alumina ceramic substrate.

Then, by firing at 1500 ° C. in a nitrogen-hydrogen mixed gas atmosphere containing a slight amount of water vapor, organic substances in the conductor paste are decomposed and disappeared, and the conductor is baked on an alumina ceramic substrate to form bumps. did.

Then, the surface of this bump was plated with Ni and Au.

Then, the height of the bumps of 200 samples obtained by the above method was measured by a surface roughness meter (surfcom112B manufactured by Tokyo Seimitsu Co., Ltd.), and the variation was extremely uniform within 1 μm. , There was no short circuit between bumps at all. Further, when an integrated circuit was mounted by a flip chip method using the alumina substrate on which the bumps were formed, no defective connection between the bumps on the alumina ceramic substrate and the bumps formed on the integrated circuit was observed.

[Comparative Example 1] Fine wiring was manufactured on an alumina ceramics substrate under exactly the same conditions as in Example 1 except that the conductor paste filling step was performed by the method described below.

In the conductor paste filling step, first, a small amount of conductor paste is placed on the surface of the positive photoresist layer, and the Teflon knife edge is used to contact the positive photoresist layer surface with the Teflon knife edge. The conductive paste was filled in the groove formed in the photoresist layer.
As a result, it was found that the excess thick film paste was deposited on the surface of the positive photoresist layer other than the groove portion, so that the wiring was short-circuited after firing.

[Comparative Example 2] The conductor paste used in Example 1 was used, and the screen used in Example 1 was used.
A wiring pattern was manufactured on the alumina ceramics substrate under exactly the same conditions as in Example 1 except that the wiring pattern was directly screen-printed on the alumina ceramics substrate.

As a result, it was found that the printed wiring pattern was bleeding at the time of screen printing and short-circuited between the manufactured wirings.

[0073]

As described in detail above, in the method for forming a conductor layer pattern according to the present invention, a photoresist layer forming step of forming a positive photoresist layer on a ceramic substrate, and the positive photoresist A concave portion forming step of forming a concave portion in the conductor layer forming pattern on the positive photoresist layer by subjecting the layer to an exposure treatment through a photomask having a predetermined conductor layer forming pattern, and then performing a developing treatment; Using a screen having the same pattern as the conductor layer forming pattern and a whole surface exposure treatment step of subjecting the positive type photoresist layer having the recessed portion to a whole surface exposure treatment, a conductor paste is applied to the recessed portion by a screen printing method. A conductor paste filling step for filling,
An adhesion step of drying the conductor paste filled in the recesses and adhering a solid component in the conductor paste to the ceramic substrate, and performing a development process on the positive photoresist layer to form the positive photoresist layer. Since it includes a photoresist layer disappearing step of disappearing and a baking step of baking the solid component in the conductor paste on the ceramic substrate by baking, the conductor has an accurate and extremely fine shape as compared with the conventional method. It is possible to inexpensively manufacture a conductor layer pattern in which layers are reliably insulated.

In the photoresist layer disappearing step,
Since the photoresist layer is erased by the developing process by utilizing the characteristics of the positive photoresist, the conductor layer and the substrate material are different from the case where the photoresist layer is erased by the conventional combustion method. It is possible to eliminate thermal damage and oxidative damage to the etc.

[Brief description of drawings]

1A to 1G are cross-sectional views schematically showing each step in a method for forming a conductor layer pattern according to the present invention.

[Explanation of symbols]

 11 Ceramics Substrate 12 Positive Photoresist Layer 13 Photomask 15 Recess 16 Conductor Paste 17 Screen 19 Conductor Layer

Front Page Continuation (72) Inventor Kazushige Tanaka 2701-1 Iwakura, East Branch, Omine Town, Mine City, Yamaguchi Prefecture Sumitomo Metal Ceramics Co., Ltd.

Claims (1)

[Claims] 1. A photoresist layer forming step of forming a positive photoresist layer on a ceramics substrate, an exposure process is performed on the positive photoresist layer through a photomask having a predetermined conductor layer forming pattern, and then, A recess forming step of forming a recess in the conductor layer forming pattern on the positive photoresist layer by performing a development process, and a whole surface exposure of performing a whole surface exposure process on the positive photoresist layer in which the recess is formed A treatment step, using a screen having the same pattern as the conductor layer forming pattern, a conductor paste filling step of filling the recess with a conductor paste by a screen printing method, and drying the conductor paste filled in the recess, A bonding step of bonding a solid component in the conductor paste to the ceramic substrate, It is characterized in that it includes a photoresist layer disappearance step of developing the photoresist layer to disappear the positive photoresist layer, and a baking step of baking solid components in the conductor paste onto the ceramic substrate by baking. Method for forming conductor layer pattern.