JPH0738489B2 - Electronic material ceramic and substrate for electronic circuit using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electronic material ceramic that can be used as a magnetic capacitor or a magnetic substrate incorporating such a capacitor, and a substrate for an electronic circuit configured using the same. Regarding

[Conventional technology]

Conventionally, an electronic circuit substrate is configured to include only a conductor circuit, a conductor circuit and a resistor, or a conductor circuit and a resistor and a limited range of capacitors, and other functional parts are separated as elements and mounted on the substrate. It had been.

That is, for example, in the conventional porcelain substrate, the substrate having the conductor and the resistor built therein is the center, and the capacitor is mounted by soldering as a chip component or the like. Therefore, there is a limit to downsizing the electronic circuit. One example is shown in FIG. 51 is a porcelain substrate, 52 is a conductor circuit, 53 is a resistor, and 54 is a chip capacitor.

In recent years, attempts have been made to incorporate a plurality of capacitors in a substrate by changing the dielectric constant within the same porcelain substrate. That is, as shown in FIG. 9, it is an attempt to form a plurality of capacitors on the same substrate by separating a portion 61 having a high dielectric constant ε ₁ and a portion 62 having a low dielectric constant ε ₂ . However, conventionally, it is very difficult to form different dielectric parts in the same substrate, and it is obvious that, for example, considering the complexity of manufacturing a monolithic ceramic capacitor, a substrate containing a plurality of capacitors Is currently not realized or put into practical use.

[Problems to be Solved by the Invention]

The present invention has been made to solve the conventional problems and provide an electronic material ceramic capable of defining a plurality of high dielectric portions.

The present invention is also made to provide a substrate for an electronic circuit capable of incorporating a plurality of capacitors by using such an electronic material ceramic.

The present invention has been further made to provide an inexpensive electronic circuit substrate which has many functional parts including a dielectric and is miniaturized.

[Means for solving problems]

That is, the electronic material ceramic provided by the present invention is a molded body containing a dielectric or a precursor thereof, and the molded body is formed by applying a metal or a metal oxide to the surface of the primary fired body of the molded body material. Then, the molded body is formed by secondary firing to form a grain boundary insulating layer, and has a portion with a different dielectric constant formed by filling a recess provided in the molded body with a substance having a different dielectric constant. It is characterized by
The electronic circuit substrate provided by the present invention is characterized by being made of the above-mentioned electronic material ceramic.

[Specific Description and Examples of Invention]

In the present invention, the above-mentioned molded article refers to, for example, a green compact (a powdered solid of a raw material such as a metal oxide), a fired body or a sintered body (porcelain, etc.), and the electronic material of the present invention. A dielectric that constitutes ceramics or a precursor for forming a dielectric (for example, the above-mentioned powdered solid or a solid composed of semiconductor porcelain or semiconductor particles obtained by primary firing when synthesizing a high dielectric). Etc.) are included.

A feature of the electronic material ceramic of the present invention is that the recesses provided in the molded body are filled with substances having different permittivities, and portions having different permittivities are formed through a process such as firing as necessary. . Therefore, a single or a plurality of recesses are provided in the molded body, and by filling with a substance having a low dielectric constant, for example, the portions to be made to have a high dielectric constant are separated into two or more around the recesses and separated from each other. Two or more high-dielectric parts can be defined.

As one example, a porcelain substrate composed of a grain boundary insulation type high-dielectric material is usually a powder compact formed by adding components such as Dy ₂ O ₃ and SiO ₂ to BaTiO ₃ and mixing them. After firing, it becomes a semiconductor, and then a metal or metal oxide (for example,
Cu, CuO, MnO ₂ , Tl ₂ O _3, etc.) is applied and secondary firing is performed to form a grain boundary insulating layer. When carrying out the present invention in this example, first of all, the desired powder-compacted shaped body, a fired body after primary firing, a fired body having a surface coated with a metal or a metal oxide, or a fired body after secondary firing is used. A recess having a desired shape (for example, a recess formed in the surface layer portion) is provided in the portion. The number of recesses is appropriately determined depending on the number of dielectrics to be defined. Examples of the method of providing the recess include a method of press molding of a green compact, laser processing, mechanical processing (for example, diamond cutting), ultrasonic processing, and the like.

Then, the recesses thus provided are filled with, for example, a substance having a low dielectric constant, and a subsequent step for obtaining a porcelain substrate, or a third firing that is performed as necessary,
A porcelain substrate having a plurality of high-dielectric portions defined is obtained. The high permittivity portions defined may have the same or different dielectric constants. Examples of the method of making the different materials include a method of changing the type of coating additive. Incidentally, as the low dielectric constant material used to obtain the porcelain substrate in this example, the melting point is often low is still further than ceramic body, for example _{PbSiO 3, BSiO 3, LiSiO 3} , various crystallized glass is preferred Is.

A plurality of capacitors can be built in the thus obtained porcelain substrate by providing conductor portions (electrodes, lead portions, etc.) on the surface of each high dielectric portion. Furthermore, a conductor portion (for example, a through-hole conductor) and a resistor or an insulator portion (for example, formed by a normal thin film or thick film forming method) are formed inside or around the porcelain substrate, It can be a substrate with many functional parts.

Hereinafter, the present invention will be described in more detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.

Embodiment 1 FIG. 1 shows a manufacturing process of a porcelain substrate which is an embodiment of the present invention. In this embodiment, as shown in FIG. 2 (a), the recess 2 is formed in the molded body 1 during press molding. Next, in the same process as when manufacturing a normal porcelain capacitor, BaTiO ₃ −
Form a Dy ₂ O ₃ —SiO ₂ system dielectric ceramic. That is, the molded body is subjected to primary firing in a predetermined atmosphere, then an additive such as CuO is applied, and secondarily fired in an oxidizing atmosphere to obtain a dielectric ceramic substrate. After filling the concave portion of the dielectric ceramic substrate with, for example, PbSiO ₃ powder 3 as shown in FIG. 2 (b), third firing is performed. Further, a C, R built-in substrate is obtained by forming a predetermined conductor portion, resistor portion, and insulator portion on the porcelain substrate.

Embodiment 2 FIG. 3 shows another manufacturing process of a porcelain substrate which is an embodiment of the present invention. In this embodiment, a molded body 21 having a desired shape is obtained by molding (FIG. 4 (a)), and a concave portion 23 is formed by laser irradiation on a porcelain substrate 22 semiconductorized by primary firing (FIG. 4 (b)). ). Next, apply the additive,
Secondary firing is performed to obtain a dielectric ceramic substrate. The concave portion of the porcelain substrate is filled with, for example, PbSiO ₃ powder 24 as shown in FIG. 4 (c). Next, tertiary firing is performed. Further, by forming a predetermined conductor portion, resistor portion, and insulator portion on this substrate, a C / R built-in substrate can be obtained.

Embodiment 3 FIG. 5 shows another manufacturing process of a porcelain substrate which is an embodiment of the present invention. In this embodiment, a molded body 31 having a desired shape is obtained by molding (FIG. 6 (a)), the additive is applied to the porcelain substrate which has been made into a semiconductor by the primary firing, and then the secondary firing is performed to perform the dielectric porcelain substrate 32. To get A concave portion 33 is formed on this porcelain substrate by machining using a diamond tool (FIG. 6 (b)), and the concave portion is filled with, for example, PbSiO ₃ powder 34 as shown in FIG. 6 (c). Next, tertiary firing is performed. By forming a predetermined conductor portion, resistor portion, and insulator portion on the substrate, a C / R built-in substrate can be obtained.

Incidentally, FIG. 7 shows an example of the porcelain substrate of the present invention obtained by the steps as shown in the above embodiment. FIGS. 7 (a) and 7 (b) are a plan view and a sectional view of the porcelain substrate, respectively, where 41 is a high dielectric portion and 42 is a low dielectric portion. Further, FIG. 7C shows a porcelain substrate on which a conductor portion 43, a resistor portion 44, and an insulator portion 45 are further formed.

[Effect of the Invention] The electronic material ceramic of the present invention can define a plurality of dielectrics having different dielectric constants. Therefore, the electronic circuit substrate of the present invention constructed by using this can incorporate a plurality of capacitors having various capacities, and various functional parts such as conductors, resistors, and insulators can be formed on this substrate. As a result, an inexpensive electronic circuit substrate having a large number of functional parts and having a small size can be obtained. Further, in this way, the degree of freedom in designing capacitors, resistors, etc. in the substrate can be greatly improved.

In the present invention, the recesses provided in the molded body are filled with substances having different dielectric constants. For example, it is possible to achieve a low dielectric constant without a filler, that is, only in the air phase. The strength of the substrate itself becomes a problem because a part of the substrate becomes extremely thin. Therefore, the effect of improving the strength can be achieved by filling the concave portion with the filler.

Further, in the present invention, since the concave portion is formed in the molded body, the bottom portion or the central portion is integrated. Therefore, there is an effect that the strength of the substrate is maintained as compared with the conventional structure in which the through hole is formed.

[Brief description of drawings]

FIG. 1 is a process explanatory view for explaining a manufacturing process of a porcelain substrate which is one embodiment of the present invention, and FIG. 2 (a) is a cross-sectional view of a press-formed product in which a recess is formed at this time. ,
(B) shows a cross-sectional view of a porcelain substrate having recesses filled with substances having different dielectric constants. FIG. 3 is a process explanatory view for explaining another manufacturing process of the porcelain substrate which is one embodiment of the present invention. FIG. 4 (a) is a molded body at this time, and FIG. 3C is a cross-sectional view of a semiconductor porcelain substrate in which the recesses are formed, and FIG. FIG. 5 is a process explanatory view for explaining still another manufacturing process of the porcelain substrate which is one embodiment of the present invention. FIG. 6 (a) is a molded product at this time, and FIG. A dielectric ceramic substrate having a recess formed therein, and (c) are cross-sectional views of the dielectric ceramic substrate having the recess filled with substances having different permittivities. FIG. 7A is a plan view of a porcelain substrate which is one embodiment of the present invention, FIG. 7B is a sectional view taken along line AA in FIG. 7A, and FIG.
FIG. 3 is a cross-sectional view of a porcelain substrate with built-in R and C in which functional parts such as conductors, resistors, and insulators are further formed on this porcelain substrate. FIG. 8 is a sectional view of a conventional porcelain substrate. FIG. 9 is a cross-sectional view of a porcelain substrate having a plurality of high-dielectric-constant portions according to a conventionally attempted method. 1,21,31 …… Molded body, 2,23,32,41 …… Dielectric porcelain, 3,24,3
3,42 …… Low dielectric constant material, 22 …… Semiconductor porcelain, 43 …… Conductor, 4
4 ... Resistor, 45 ... Insulator.

Claims (9)

[Claims] 1. A molded body containing a dielectric or a precursor thereof, which is formed by applying a metal or a metal oxide to the surface of a primary fired body of the molded body material and secondarily firing it. An electronic material ceramic, which is a molded body in which a field insulating layer is formed, and which is formed by filling a recess provided in the molded body with a substance having a dielectric constant different from that of the molded body. 2. The electronic material ceramic according to claim 1, wherein the recess has a low dielectric constant by being filled with a substance having a low dielectric constant. 3. The electronic material ceramic according to claim 1, wherein the molded body is made of a BaTiO ₃ —Dy ₂ O ₃ —SiO ₂ system material. 4. The electronic material ceramic according to claim 1, wherein the substance is PbSiO ₃ . 5. A molded body containing a dielectric or a precursor thereof, wherein the molded body is formed by applying a metal or a metal oxide to the surface of a primary fired body of the molded body material and then performing secondary firing. A molded body having a field insulating layer formed thereon, which is composed of an electronic material ceramic formed by filling a recess provided in the molded body with a substance having a dielectric constant different from that of the molded body. A substrate for an electronic circuit characterized by: 6. The method according to claim 5, wherein the recess has two or more high-dielectric portions which are separated from each other with a portion having a low dielectric constant filled with a low-dielectric material being sandwiched therebetween. A substrate for an electronic circuit according to item. 7. The claim (5) or claim (5) further comprising a functional portion of at least one of a conductor, a resistor and an insulator inside or around the ceramic. A substrate for an electronic circuit according to item 6). 8. The electronic circuit substrate according to claim 5, wherein the molded body is made of a BaTiO ₃ --Dy ₂ O ₃ --SiO ₂ system material. 9. The electronic circuit substrate according to claim 5, wherein the substance is PbSiO ₃ .