Multilayer circuit component and method for manufacturing the same Number:7,146,719 from the United States Patent and Trademark Office (PTO) owispatent

Title: Multilayer circuit component and method for manufacturing the same

Abstract: A multilayer circuit component and a method for manufacturing the same, in which the difference of the amounts of baking shrinkages between each of the glass-containing layers is small, and the enlargement rate of the diameter of the via hole formed in each of the glass-containing layers is close to those in the other layers, so that it is possible to prevent a short circuit defect due to the mutual short circuit of the conductors in the via hole from occurring, and the warp of the substrate is reduced. The multilayer circuit component is provided with at least two glass-containing layers on a substrate, differentiating the softening temperature of glass compounded in the first glass-containing layer formed on the substrate from the softening temperature of glass compounded in the second glass-containing layer formed on the first glass-containing layer. The difference in the sintering properties due to the difference between the wettabilities is counterbalanced, and therefore, a multilayer circuit component, in which the warp of the substrate is reduced, and the degree of the enlargement of the via hole diameter of each of the glass-containing layers during baking is uniform, is produced.

Patent Number: 7,146,719 Issued on 12/12/2006 to Iha

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Inventors:	Iha; Michiaki (Otsu, JP)
Assignee:	Murata Manufacturing Co., Ltd. (JP)
Appl. No.:	10/815,659
Filed:	April 2, 2004

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Related U.S. Patent Documents

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	Application Number	Filing Date	Patent Number	Issue Date
	09881974	Jun., 2001	6759115

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Foreign Application Priority Data

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Jun 15, 2000 [JP]			2000-180086
Jul 07, 2000 [JP]			2000-206262

Current U.S. Class:	29/830 ; 29/825; 29/832; 29/852; 428/209; 428/414; 428/415
Current International Class:	H05K 3/36 (20060101)
Field of Search:	29/825,830,832,852 428/209,414,415

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References Cited [Referenced By]

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U.S. Patent Documents

	4769309		September 1988		King et al.
	5827605		October 1998		Nishide et al.
	5928839		July 1999		Rath et al.
	6159322		December 2000		Ogata et al.
	6190834		February 2001		Narahara et al.
	6534723		March 2003		Asai et al.
	6759115		July 2004		Iha

Foreign Patent Documents

	2145574		Mar., 1985		GB
	53008771		Jul., 1976		JP
	55-62799		May., 1980		JP
	63-194395		Aug., 1988		JP
	63-261796		Oct., 1988		JP
	7-312511		Nov., 1995		JP
	08-236936		Sep., 1996		JP
	10-65335		Mar., 1998		JP
	11-224825		Aug., 1999		JP
	11-330694		Nov., 1999		JP

Primary Examiner: Arbes; Carl J.
Attorney, Agent or Firm: Dickstein, Shapiro, LLP.

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Parent Case Text

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This is a division of application Ser. No. 09/881,974, filed Jun. 14, 2001 now U.S. Pat. No. 6,759,115.

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Claims

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What is claimed is:

1. A method for manufacturing a multilayer circuit component which comprises at least two glass-containing layers on a substrate, in which the baking shrinkage rates of the first glass-containing layer and second glass-containing layer formed are about the same, comprising: (a) applying and drying a first photosensitive glass paste comprising glass having a softening temperature and a photosensitive vehicle to a substrate; (b) forming a via hole pattern on the resulting dried first paste; (c) baking the resulting paste with said via hole pattern so as to form a first glass-containing layer; (d) applying and drying a second photosensitive glass paste comprising glass having a softening temperature and a photosensitive vehicle, on said first glass-containing layer; (e) forming a via hole pattern on the resulting dried second paste; and (f) baking the resulting second paste with said via hole pattern so as to form a second glass-containing layer; wherein at least one parameter selected from glass softening temperature and glass content in the first glass paste is different from the same parameter in the second glass paste, whereby the baking shrinkage rates of the first glass-containing layer and second glass-containing layer formed are about the same.

2. A method for manufacturing a multilayer circuit component according to claim 1, wherein the glass softening temperature parameter in the first glass paste is different from the glass softening temperature parameter in the second glass paste.

3. A method for manufacturing a multilayer circuit component according to claim 2, wherein the glasses in the pastes are such that the glass of the first glass-containing layer has a contact angle relative to said substrate which is larger than the contact angle of the glass of the second glass-containing layer relative to said first glass-containing layer; and the softening temperature of the glass in the first photosensitive glass paste is lower than the softening temperature of the glass in the second photosensitive glass paste.

4. A method for manufacturing a multilayer circuit component according to claim 2, wherein the glasses in the pastes are such that the glass of the first glass-containing layer has a contact angle relative to said substrate which is smaller than the contact angle of the glass of the second glass-containing layer relative to said first glass-containing layer; and the softening temperature of the glass in the first photosensitive glass paste is higher than the softening temperature of the glass in the second photosensitive glass paste.

5. A method for manufacturing a multilayer circuit component according to claim 2, wherein the difference between the softening temperature of the glass in the first photosensitive glass paste and the softening temperature of the glass in the second photosensitive glass paste is at least about 30.degree. C.

6. A method for manufacturing a multilayer circuit component according to claim 1, wherein the glass content in the first glass paste is different from the glass content in the second glass paste.

7. A method for manufacturing a multilayer circuit component according to claim 6, wherein the first and second photosensitive glass pastes each comprise low softening temperature glass and the low softening temperature glass content in the first and second photosensitive glass pastes are different.

8. A method for manufacturing a multilayer circuit component according to claim 7, wherein the first and second photosensitive glass pastes each comprise ceramic.

9. A method for manufacturing a multilayer circuit component according to claim 1, wherein the glass in each of the first and second photosensitive glass pastes comprise low softening temperature glass.

10. A method for manufacturing a multilayer circuit component according to claim 1, wherein the glass in the first photosensitive glass paste comprises low softening temperature glass.

11. A method for manufacturing a multilayer circuit component according to claim 1, wherein the first and second photosensitive glass pastes each comprise ceramic.

12. A method for manufacturing a multilayer circuit component according to claim 11, wherein the substrate is a glass-free ceramic.

13. A method for manufacturing a multilayer circuit component according to claim 12, wherein the glass in the first photosensitive glass paste comprises low softening temperature glass.

14. A method for manufacturing a multilayer circuit component according to claim 13, wherein the glass in the second photosensitive glass paste comprises low softening temperature glass.

15. A method for manufacturing a multilayer circuit component according to claim 14, wherein the glass content in the first glass paste is different from the glass content in the second glass paste.

16. A method for manufacturing a multilayer circuit component according to claim 14, wherein the glass softening temperature parameter in the first glass paste is different from the glass softening temperature parameter in the second glass paste.

17. A method for manufacturing a multilayer circuit component according to claim 16, wherein the glass softening temperature parameters differ be at least about 30.degree. C.

18. A method for manufacturing a multilayer circuit component according to claim 1, wherein the substrate is a glass-free ceramic.

19. A method for manufacturing a multilayer circuit component according to claim 18, wherein the glass content in the first glass paste is different from the glass content in the second glass paste.

20. A method for manufacturing a multilayer circuit component according to claim 19, wherein the in the first glass paste is different from the glass in the second glass paste.

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Description

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BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a multilayer circuit component and a method for manufacturing the same. In particular, the present invention relates to a multilayer circuit component having a structure in which at least two layers of glass-containing layers are provided on a substrate, and a method for manufacturing the same.

2. Description of the Related Art

Semiconductor elements, such as ICs, have hitherto been mounted on printed circuit substrates, such as glass epoxy substrates, and alumina ceramic substrates. In recent years, requirements for higher packing densities, finer wirings, higher transmission speeds, higher frequencies and higher heat dissipations of the semiconductor elements have been intensified.

Conventional printed circuit substrates, such as glass epoxy, do not always have sufficient properties regarding its through hole plating property, workability, multilayer adhesion property, thermal deformation resistance at a high temperature, etc., so that there is a limit in practice regarding the increase in density. Nevertheless, expectations for ceramic substrates having large mechanical strength and high thermal resistance are running high.

For example, an alumina substrate, which is one of the ceramic substrates, has large mechanical strength and superior thermal resistance, so that various multilayer circuit components have been developed in which fine wirings are provided on the alumina substrates, and furthermore, insulation layers provided with through holes are formed by a green sheet lamination method or a printing method.

For example, a laminated air-core coil used as an inductor is produced by repeating the steps of forming a coil (coil pattern) on an alumina substrate from a conductor paste, forming an insulation layer provided with a via hole thereon, filling the via hole with a conductor and forming a second layer of coil (coil pattern) on the insulation layer. Since a spiral type coil is produced, high inductance can be produced.

As the method for manufacturing the laminated air-core coil, a method in which a screen plate coated with a photosensitive emulsion, etc., for forming a predetermined pattern is produced, and then a paste is applied by printing on a substrate or an insulation layer through the resulting screen plate using, e.g. a squeegee, and a method in which a conductor paste having photo-hardening property is applied by printing on all over the surface of a substrate or an insulation layer with a spin coating method, etc., and then a coil is formed by exposure and development through a photomask provided with a desired pattern, are known.

As a method for forming an insulation layer provided with a via hole at which a part of a conductor pattern is exposed, in a manner similar to that in the aforementioned case of the formation of the coil, there are a method in which a coating of a paste is applied by a screen printing, and a method in which exposure and development are performed using a photosensitive paste. In addition, there is a method in which a green sheet is produced from a compound of an insulation powder and an organic binder, a through hole is formed by punching at a predetermined location of the green sheet, and thereafter, this is stacked on a substrate or an insulation layer provided with a conductor and is pressure-bonded.

For example, in the formation of a plurality of insulation layers containing glass on a ceramic sintered substrate made of alumina, etc., each of the insulation layers has been hitherto formed using the same material containing the same glass. When each of the insulation layers is, however, conventionally formed by coating and baking of a material in which the same type of glass is compounded, the wettability of the first insulation layer (first glass-containing layer) formed on the ceramic sintered substrate made of alumina, etc., relative to the sintered substrate and the wettability of the second insulation layer (second glass-containing layer) formed on the first glass-containing layer relative to the first glass-containing layer are different. This difference in the wettability affects the sinterability of each of the glass-containing layers to a large degree. That is, since large differences in the amount of baking shrinkages and in the shrinkage behavior occur due to the difference in the sinterability between the first glass-containing layer and the second glass-containing layer, there are problems in that remarkable warps occur in the substrates, and in particular, when the via hole is formed in each of the insulation layer, the diameter of the via hole is enlarged.

Table 1 shows wettabilities (contact angles) of borosilicate glass relative to an alumina substrate, a crystalline quartz (SiO.sub.2) substrate and a borosilicate glass substrate. The wettability of the glass can be evaluated by the contact angle, and when the wettability becomes better, the contact angle decreases.

TABLE-US-00001 TABLE 1 Contact angle of borosilicate glass (SiO.sub.2:B.sub.2O.sub.3:(K.sub.2O = 79:19:2) Substrate relative to substrate at 1,000.degree. C. Alumina 48.degree. SiO.sub.2(Crystalline Quartz) 140.degree. Borosilicate Glass 8.degree. (SiO.sub.2:B.sub.2O.sub.3:K.sub.2O = 79:19:2)

As shown in Table 1, the contact angle of the borosilicate glass relative to the alumina substrate, frequently used as the substrate of the multilayer circuit component, is 48.degree., the contact angle of the borosilicate glass relative to the crystalline quartz (SiO.sub.2) substrate is 140.degree., and the contact angle of the borosilicate glass relative to the borosilicate glass substrate (the contact angle of borosilicate glasses relative to each other) is 8.degree.. Therefore, when comparisons are made between the alumina substrate and the borosilicate glass substrate, it is clear that the wettability of the glass relative to the alumina substrate is inferior by a large degree.

As a consequence, when the insulation layers (glass-containing layers) are laminated on the alumina substrate by a sequential baking method, in which the layers are baked one by one, since the insulation layer at the first layer (the first glass-containing layer) is baked on the alumina substrate, viscous flow is not likely to occur and the sinterability tends to be inferior. On the other hand, since the insulation layer at the second layer (the second glass-containing layer) formed on the first glass-containing layer is baked on the first glass-containing layer having excellent wettability, viscous flow starts early on, so that the sintering is likely to be accelerated compared to that in the case in which the first glass-containing layer is baked on the alumina substrate.

When the sinterability of the second glass-containing layer is improved, the baking shrinkages in the second glass-containing layer and glass-containing layers thereafter are accelerated, so that the diameters of the formed via holes become larger than that in the first layer. Accordingly, the exposure region is increased in excess of the required exposure region, and sometimes, not only the conductor pattern planned to be exposed, but also the conductor pattern adjacent thereto is exposed, so that when the via hole is filled with the conductor, a short circuit with the adjacent conductor pattern may occur, i.e., there is a circuit defect.

FIG. 1 shows a state of an insulation layer (the first glass-containing layer) 54a, provided with a via hole 53a and formed by applying a coating of an insulation material paste containing glass on a substrate 51, on which a conductor pattern (circuit) 52a is formed, and by baking, according to a conventional process for manufacturing a multilayer circuit component. FIG. 2 shows a state of an insulation layer (the second glass-containing layer) 54b, provided with a via hole 53b and formed by applying an insulation material paste containing glass on the first glass-containing layer 54a, on which conductor patterns (circuits) 52b and 52c are provided, and by baking.

As shown in FIGS. 1 and 2, according to the aforementioned conventional method for manufacturing the multilayer circuit component in which the same insulation material paste, with the same glass being compounded, is applied by coating and is baked, the baking shrinkage in the second glass-containing layer 54b is accelerated, so that the diameter of the via hole 53b of the second glass-containing layer 54b becomes larger than that of the via hole 53a in the first glass-containing layer 54a. Accordingly, when the via hole conductor 55 is introduced from the via hole 53b, there is a problem in that the via hole conductor 55 is not only connected to the planned conductor pattern 52b, but also short-circuited with the adjacent conductor patterns 52c exposed at the via hole 53b, so as to cause the short circuit defect.

Furthermore, since the residual stress of the substrate is unevenly generated due to the difference in the amounts of baking shrinkages, even when the properties, such as the thermal expansion and the thermal shrinkage, of the glass constituting the first glass-containing layer coincide with those of the substrate, the degree of the thermal shrinkage in the second glass-containing layer formed on the first glass-containing layer is different from that in the first glass-containing layer, so that a warp occurs in the substrate, and there is a problem in that the manufacture of the multilayer circuit component is difficult.

SUMMARY OF THE INVENTION

The present invention was made to solve the aforementioned problems. Accordingly, it is an object of the present invention to provide a multilayer circuit component and a method for manufacturing the same in which the difference of the amounts of baking shrinkages between each of the glass-containing layers is small and the enlargement rate of the diameter of the via hole formed in each of the glass-containing layers is close to those in the other layers, so that it is possible to prevent the short circuit defect due to the mutual short circuit of the conductors in the via hole from occurring, and the warp of the substrate is reduced.

In order to achieve the aforementioned objects, according to an aspect of the present invention, a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate is provided in which among the at least two layers of glass-containing layers, the softening temperature of glass compounded in the first glass-containing layer formed on the substrate and the softening temperature of glass compounded in the second glass-containing layer formed on the aforementioned first glass-containing layer are different.

By differentiating the softening temperature (Ts) of the glass compounded in the first glass-containing layer formed on the substrate from the softening temperature of the glass compounded in the second glass-containing layer formed on the first glass-containing layer, it is possible to control the wettabilities relative to the substrate, the glass-containing layer, etc., on which each of the glass-containing layers are to be formed, so as to prevent the amount of baking shrinkages of the first glass-containing layer and the second glass-containing layer from being uneven, and when the via hole is formed in the glass-containing layer, it is possible to suppress the enlargement of the via hole diameter, so as to make the degree of the enlargement of the via hole diameter in each of glass-containing layer small, to prevent the short circuit defect with adjacent conductors from occurring, and furthermore, it is possible to provide a multilayer circuit component in which the warp of the substrate is reduced.

In the present invention, the glass-containing layer includes a layer made of glass only and a layer made of the material in which glass is compounded in the inorganic component, for example, ceramic particles.

In the multilayer circuit component according to the present invention, when the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is larger than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the softening temperature of the glass compounded in the aforementioned first glass-containing layer is preferably made to be lower than the softening temperature of the glass compounded in the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is larger than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is inferior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the softening temperature of the glass compounded in the first glass-containing layer is made to be lower than the softening temperature of the glass compounded in the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is improved, while the wettability of the second glass-containing layer relative to the first glass-containing layer is reduced, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers so as to prevent the short circuit defect with adjacent conductors from occurring, and furthermore, it is possible to provide the multilayer circuit component in which the warp of the substrate is reduced.

On the other hand, when the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is smaller than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the softening temperature of the glass compounded in the aforementioned first glass-containing layer is preferably higher than the softening temperature of the glass compounded in the second glass-containing layer.

That is, when the contact angle of the glass constituting the first glass-containing layer relative to the substrate is smaller than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is superior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and the softening temperature of the glass compounded in the first glass-containing layer is made to be higher than the softening temperature of the glass compounded in the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is reduced, while the wettability of the second glass-containing layer relative to the first glass-containing layer is improved, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers so as to prevent the short circuit defect with adjacent conductors from occurring, and furthermore, it is possible to provide the multilayer circuit component in which the warp of the substrate is reduced.

The difference between the softening temperature of the glass compounded in the aforementioned first glass-containing layer and the softening temperature of the glass compounded in the aforementioned second glass-containing layer is preferably about 30.degree. C. or more.

When the difference between the softening temperature of the glass compounded in the first glass-containing layer and the softening temperature of the glass compounded in the second glass-containing layer is made to be about 30.degree. C. or more, it is possible to significantly control the wettability of the first glass-containing layer relative to the substrate and the wettability of the second glass-containing layer relative to the first glass-containing layer, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. Therefore, the effects of the present invention can be exhibited in practice.

According to another aspect of the present invention, a method for manufacturing a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate, in which among the at least two layers of glass-containing layers, the softening temperature of glass compounded in the first glass-containing layer formed on the substrate and the softening temperature of glass compounded in the second glass-containing layer formed on the first glass-containing layer are different, is provided. The aforementioned method for manufacturing the multilayer circuit component is provided with the steps of at least

(a) applying a photosensitive glass paste composed of the glass having a predetermined softening temperature or a compound of the glass having the predetermined softening temperature and an oxide, and a photosensitive vehicle, by printing on a substrate and then drying,

(b) exposing and developing a via hole pattern using a predetermined mask on the resulting printed and dried paste layer,

(c) baking the resulting paste layer with the aforementioned exposed and developed via hole pattern so as to form the first glass-containing layer,

(d) applying a photosensitive glass paste composed of glass having a softening temperature different from the softening temperature of the glass in the aforementioned first glass-containing layer and a photosensitive vehicle by printing on the aforementioned first glass-containing layer and drying,

(e) exposing and developing a via hole pattern using a predetermined mask on the resulting printed and dried paste layer, and

(f) baking the resulting paste layer with the aforementioned exposed and developed via hole pattern so as to form the second glass-containing layer.

By forming each of the glass-containing layers by way of the aforementioned steps (a) to (f), the multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate can be reliably produced, in which among the at least two layers of glass-containing layers, at least the softening temperature of the glass compounded in the first glass-containing layer formed on the substrate and the softening temperature of the glass compounded in the second glass-containing layer formed on the first glass-containing layer are different, the degree of the enlargement of the via hole diameter in each of the glass-containing layer is small, the short circuit defect with adjacent conductors is prevented from occurring and the warp of the substrate is reduced.

As the photosensitive glass paste, a photosensitive glass paste in which an inorganic component and a photosensitive vehicle are compounded in the weight ratio of about 40:60 to 70:30, is preferably used. The ratio of the inorganic component is more preferably made to be in the range of about 50:50 to 55:45.

As the photosensitive glass paste, for example, a photosensitive glass paste, in which the inorganic component and the photosensitive vehicle are dispersed using a triple roller mill can be used.

As the photosensitive vehicle usable in the present invention, a compound of a co-polymer of methyl methacrylate and methacrylic acid, a monomer, a photo initiator and a solvent, etc., can be used, although there is no particular limitation regarding specified kinds thereof.

In the method for manufacturing the multilayer circuit component according to the present invention, when the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is larger than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the softening temperature of the glass in the photosensitive glass paste used for forming the aforementioned first glass-containing layer is preferably made to be lower than the softening temperature of the glass in the photosensitive glass paste used for forming the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is larger than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, by making the softening temperature of the glass in the photosensitive glass paste used for forming the first glass-containing layer lower than the softening temperature of the glass in the photosensitive glass paste used for forming the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is improved, while the wettability of the second glass-containing layer relative to the first glass-containing layer is reduced, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers, so as to efficiently produce the multilayer circuit component in which the short circuit defect with adjacent conductors is prevented from occurring, and furthermore, the warp of the substrate is reduced.

On the other hand, when the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is smaller than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the softening temperature of the glass in the photosensitive glass paste used for forming the aforementioned first glass-containing layer is preferably made to be higher than the softening temperature of the glass in the photosensitive glass paste used for forming the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is smaller than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, by making the softening temperature of the glass in the photosensitive glass paste used for forming the first glass-containing layer higher than the softening temperature of the glass in the photosensitive glass paste used for forming the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is reduced, while the wettability of the second glass-containing layer relative to the first glass-containing layer is improved, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers, so as to efficiently produce the multilayer circuit component in which the short circuit defect with adjacent conductors is prevented from occurring, and furthermore, the warp of the substrate is reduced.

In the method for manufacturing the multilayer circuit component according to the present invention, the difference between the softening temperature of the glass in the photosensitive glass paste used for forming the first glass-containing layer and the softening temperature of the glass in the photosensitive glass paste used for forming the second glass-containing layer is preferably about 30.degree. C. or more.

By making the difference between the softening temperature of the glass in the photosensitive glass paste used for forming the first glass-containing layer and the softening temperature of the glass in the photosensitive glass paste used for forming the second glass-containing layer about 30.degree. C. or more, it is possible to significantly control the wettability of the first glass-containing layer relative to the substrate and the wettability of the second glass-containing layer relative to the first glass-containing layer, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. Therefore, the effects of the present invention can be exhibited in practice.

In the method for manufacturing the multilayer circuit component according to the present invention, it is preferable that the baking is performed after every paste layer is formed by way of the aforementioned steps of the printing and drying, and developing.

When baking is performed after every paste layer is formed by way of the aforementioned steps of the printing and drying, and developing (so-called sequential baking), the present invention is especially significant since it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers, so as to efficiently produce the multilayer circuit component in which the short circuit defect with adjacent conductors is prevented from occurring, and furthermore, the warp of the substrate is reduced.

In order to achieve the aforementioned objects, according to another aspect of the present invention, a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass and ceramic on a substrate is provided, in which among the at least two layers of glass-containing layers, at least the first glass-containing layer formed on the substrate and the second glass-containing layer formed on the aforementioned first glass-containing layer are different in glass content.

By differentiating the glass content of at least the first glass-containing layer formed on the substrate, in particular, on a ceramic sintered substrate, among the at least two layers of glass-containing layers, and the second glass-containing layer formed thereon, it is possible to control the wettabilities relative to the substrate, the glass-containing layer, etc., on which each of the glass-containing layers are to be formed, so as to prevent the amounts of baking shrinkages of the first glass-containing layer and the second glass-containing layer from being uneven, and when a via hole is formed in the glass-containing layer, it is possible to suppress the enlargement of the via hole diameter, so as to prevent the short circuit defect between conductors through the via hole conductor from occurring, and furthermore, it is possible to provide a multilayer circuit component in which the warp of the substrate is reduced.

In the multilayer circuit component according to the present invention, the glasses contained in the aforementioned first glass-containing layer and the aforementioned second glass-containing layer are preferably low softening temperature glasses.

When the glasses contained in the aforementioned first glass-containing layer and the aforementioned second glass-containing layer are low softening temperature glasses, by differentiating the contents of the low softening temperature glasses in the first glass-containing layer and in the second glass-containing layer, it is possible to control the wettabilities relative to the substrate and the glass-containing layer, etc., on which each of the glass-containing layers are formed, so as to prevent the amounts of baking shrinkages of the first glass-containing layer and the second glass-containing layer from being uneven. Consequently, it is possible to provide a multilayer circuit component in which the short circuit defect between conductors is prevented from occurring, and the warp of the substrate is reduced.

According to another aspect of the present invention, a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate is provided, in which at least the first glass-containing layer, formed on the substrate, among the at least two layers of glass-containing layers and the second glass-containing layer formed on the aforementioned first glass-containing layer contain compounded glasses composed of at least two kinds of low softening temperature glass, and the compounded glass contained in the aforementioned first glass-containing layer and the compounded glass contained in the aforementioned second glass-containing layer are different in the compounding ratios of the low softening temperature glasses. By the term low softening temperature glass is mean a glass having a softening temperature below about 650.degree. C., and preferably below about 500.degree. C.

By making at least the first glass-containing layer formed on the substrate and the second glass-containing layer formed thereon contain compounded glasses composed of at least two kinds of low softening temperature glass, and by differentiating the compounding ratios of the low softening temperature glasses in the compounded glasses contained in the first glass-containing layer and the second glass-containing layer, it is possible to control the wettabilities relative to the substrate and the glass-containing layer, etc., on which each of the glass-containing layers are to be formed, so as to prevent the amounts of baking shrinkages of the first glass-containing layer and the second glass-containing layer from being uneven, and when a via hole is formed in the glass-containing layer, it is possible to suppress the enlargement of the via hole diameter so as to prevent the short circuit defect between conductors through the via hole conductor from occurring, and furthermore, it is possible to provide the multilayer circuit component in which the warp of the substrate is reduced.

According to another aspect of the present invention, a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass and ceramic on a substrate is provided in which at least the first glass-containing layer formed on the substrate, and the second glass-containing layer formed on the aforementioned first glass-containing layer contain compounded glasses composed of at least two kinds of low softening temperature glass, and the aforementioned first glass-containing layer and the aforementioned second glass-containing layer are different in the content of the aforementioned compounded glasses.

By making at least the first glass-containing layer formed on the substrate and the second glass-containing layer formed thereon contain compounded glasses composed of at least two kinds of low softening temperature glass, and by differentiating the contents of the compounded glasses in the first glass-containing layer and the second glass-containing layer, it is possible to control the wettabilities relative to the substrate and the glass-containing layer, etc., on which each of the glass-containing layers are to be formed, so as to prevent the amounts of baking shrinkages of the first glass-containing layer and the second glass-containing layer from being uneven, and when the via hole is formed in the glass-containing layer, it is possible to suppress the enlargement of the via hole diameter, so as to prevent the short circuit defect between conductors through the via hole conductor from occurring, and furthermore, it is possible to provide the multilayer circuit component in which the warp of the substrate is reduced.

When the contact angle of the glass constituting the aforementioned first glass-containing layer in the aforementioned multilayer circuit component relative to the aforementioned substrate is larger than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the glass content of the aforementioned first glass-containing layer is preferably made to be larger than the glass content of the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is larger than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is inferior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the glass content of the first glass-containing layer is made to be larger than the glass content of the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is improved while the wettability of the second glass-containing layer relative to the first glass-containing layer is reduced, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layers, so as to prevent the short circuit defect between the conductors from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

When a contact angle of the glass constituting the aforementioned first glass-containing layer in the aforementioned multilayer circuit component relative to the aforementioned substrate is smaller than a contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the content of the low softening temperature glass in the aforementioned first glass-containing layer is preferably made to be smaller than the content of the low softening temperature glass in the aforementioned second glass-containing layer.

That is, when the contact angle of the glass constituting the first glass-containing layer relative to the substrate is smaller than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is superior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the content of the low softening temperature glass in the first glass-containing layer is made to be smaller than the content of the low softening temperature glass in the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is reduced while the wettability of the second glass-containing layer relative to the first glass-containing layer is improved, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, when the via hole is formed in the glass-containing layer, it is possible to suppress the enlargement of the via hole diameter, so as to prevent the short circuit defect between the conductors through the via hole conductor from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

When the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is larger than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the compounding ratio of the low softening temperature glass in the aforementioned first glass-containing layer is preferably made to be larger than the compounding ratio of the low softening temperature glass in the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is larger than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is inferior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the compounding ratio of the low softening temperature glass in the compounded glass of the first glass-containing layer is made to be larger than the compounding ratio of the low softening temperature glass in the compounded glass of the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is improved while the wettability of the second glass-containing layer relative to the first glass-containing layer is reduced, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layer, so as to prevent the short circuit defect between the conductors from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

When the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is smaller than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the compounding ratio of the low softening temperature glass in the compounded glass of the aforementioned first glass-containing layer is preferably made to be smaller than the compounding ratio of the low softening temperature glass in the compounded glass of the aforementioned second glass-containing layer.

That is, when the contact angle of the glass constituting the first glass-containing layer relative to the substrate is smaller than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is superior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the compounding ratio of the low softening temperature glass in the compounded glass of the first glass-containing layer is made to be smaller than the compounding ratio of the low softening temperature glass in the compounded glass of the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is reduced while the wettability of the second glass-containing layer relative to the first glass-containing layer is improved, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layer so as to prevent the short circuit defect between the conductors from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

When the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is larger than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the content of the compounded glass in the aforementioned first glass-containing layer is preferably made to be larger than the content of the compounded glass in the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is larger than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is inferior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the content of the compounded glass in the first glass-containing layer is made to be larger than the content of the compounded glass in the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is improved while the wettability of the second glass-containing layer relative to the first glass-containing layer is reduced, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layer, so as to prevent the short circuit defect between the conductors from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

When the contact angle of the glass constituting the aforementioned first glass-containing layer relative to the aforementioned substrate is smaller than the contact angle of the glass constituting the aforementioned second glass-containing layer relative to the aforementioned first glass-containing layer, the content of the compounded glass in the aforementioned first glass-containing layer is preferably made to be smaller than the content of the compounded glass in the aforementioned second glass-containing layer.

When the contact angle of the glass constituting the first glass-containing layer relative to the substrate is smaller than the contact angle of the glass constituting the second glass-containing layer relative to the first glass-containing layer, that is, when the wettability of the glass constituting the first glass-containing layer relative to the substrate is superior to the wettability of the glass constituting the second glass-containing layer relative to the first glass-containing layer, and when the content of the compounded glass in the first glass-containing layer is made to be smaller than the content of the compounded glass in the second glass-containing layer, it is possible that the wettability of the first glass-containing layer relative to the substrate is reduced while the wettability of the second glass-containing layer relative to the first glass-containing layer is improved, so as to counterbalance the difference in the sintering properties due to the difference between the wettabilities of each of the glass-containing layers, and to reduce the difference in the amounts of the baking shrinkages of the first and the second glass-containing layers. As a result, it is possible to suppress the enlargement of the via hole diameter in each of the glass-containing layer, so as to prevent the short circuit defect between the conductors from occurring, and furthermore, it is possible to produce the multilayer circuit component in which the warp of the substrate is reduced.

According to another aspect of the present invention, a method for manufacturing a multilayer circuit component provided with at least two glass-containing layers composed of materials containing glass and ceramic on a substrate is provided. The aforementioned method for manufacturing the multilayer circuit component is provided with the steps of at least

(a) applying a photosensitive glass paste composed of glass, ceramic and a photosensitive vehicle by printing on a substrate and then drying,

(b) exposing and developing a via hole pattern using a predetermined mask on the resulting printed and dried paste layer,

(c) baking the resulting paste layer with the aforementioned exposed and developed via hole pattern so as to form the first glass-containing layer,

(d) applying a photosensitive glass paste composed of glass, ceramic and a photosensitive vehicle, in contents different from those in the aforementioned first glass-containing layer, by printing on the aforementioned first glass-containing layer and then drying,

(e) exposing and developing a via hole pattern using a predetermined mask on the resulting printed and dried paste layer, and

(f) baking the resulting paste layer with the aforementioned exposed and developed via hole pattern so as to form the second glass-containing layer.

By forming each of the glass-containing layers with the aforementioned steps (a) to (f), the multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate can be reliably produced, in which the first glass-containing layer formed on the substrate and the second glass-containing layer formed thereon are different in glass content, the unevenness in the amounts of the baking shrinkages of the first and the second glass-containing layers is reduced, the degree of the enlargement of the via hole diameter in each of the glass-containing layer is reduced by a great degree, the short circuit defect between the conductors is prevented from occurring and the warp of the substrate is reduced.

The glass constituting the photosensitive glass paste used for forming the aforementioned first glass-containing layer and the glass constituting the photosensitive glass paste used for forming the aforementioned second glass-containing layer are preferably low softening temperature glasses.

In the case in which the glass constituting the photosensitive glass paste used for forming the first glass-containing layer and the glass constituting the photosensitive glass paste used for forming the second glass-containing layer are low softening temperature glasses, by differentiating the glass contents of the first glass-containing layer and the second glass-containing layer, a multilayer circuit component in which the unevenness in the amounts of the baking shrinkages of the first and the second glass-containing layers is reduced, the degree of the enlargement of the via hole diameter in each of the glass-containing layer is reduced by a great degree, the short circuit defect between the conductors is prevented from occurring and the warp of the substrate is reduced can be reliably produced.

As the photosensitive glass paste, a photosensitive glass paste in which an inorganic component and a photosensitive vehicle are compounded in the weight ratio of about 40:60 to 70:30, is preferably used. The ratio of the inorganic component is more preferably made to be about 50:50 to 55:45.

As the photosensitive glass paste, for example, a photosensitive glass paste in which the inorganic component and the photosensitive vehicle are dispersed using a triple roller mill, etc., can be used.

As the photosensitive vehicle usable in the present invention, a compound of a co-polymer of methyl methacrylate and methacrylic acid, a monomer, a photo initiator and a solvent, etc., can be used, although there is no particular limitation regarding specified kinds thereof.

According to another aspect of the present invention, a method for manufacturing a multilayer circuit component provided with at least two layers of glass-containing layers composed of materials containing glass on a substrate is provided. The aforementioned method for manufacturing the multilayer circuit component is provided with the steps of at least

(a) applying a photosensitive glass paste composed of a compounded glass, containing at least two kinds of glasses including a low softening temperature glass, and a photosensitive vehicle by printing on a substrate, and then, drying,

(b) exposing and developing a via hole pattern using a predetermined mask on the resulting printed and dried paste layer,

(c) baking the resulting paste layer with the aforementioned exposed and developed via hole pattern so as to form the first glass-containing layer,

(d) applying a photosensitive glass past