JPH0748535B2 - Method for manufacturing graded ceramic substrate - Google Patents

Description

Description: (a) Field of Industrial Application The present invention relates to a method for manufacturing a glazed ceramic substrate in which the surface of a ceramic substrate is glazed.

(B) Conventional Technology Conventionally, insulating ceramics materials have been widely used for substrates of electronic parts and the like by taking advantage of electrical characteristics such as insulation and physical characteristics such as heat resistance. Generally, when forming a conductor wiring pattern of metal or the like on the surface of a ceramics substrate, in order to eliminate the influence of irregularities on the surface of the ceramics substrate, a glaze ceramics substrate subjected to glaze is used as a base of the wiring pattern. Conventionally, the following method has been adopted as a method for manufacturing a glaze ceramics substrate.

First, the ceramic powder is mixed with a binder to form a green sheet, or the ceramic powder is formed into a plate shape and then baked at about 1400 ° C. to form a ceramic substrate. A glaze tape formed by mixing the glass frit 2 and an organic resin into a sheet is attached to the surface of the ceramic substrate, or the glass substrate is dipped in a glaze tank or screen-printed with a glass paste to form a glaze on the surface of the ceramic substrate. Coat the membrane. Then, by heating to about 1200-1300 ℃,
Glaze is baked on the surface of the ceramic substrate.

(C) Problems to be Solved by the Invention The ceramic substrate manufactured by such a conventional method may cause a problem when a continuous wiring pattern is formed from the flat surface portion to the end surface portion of the substrate. The cross-sectional shape of the glaze ceramics substrate manufactured by the conventional manufacturing method is shown in FIGS. 3 and 4. Figure 3 shows a thickness of 3mm,
This is an example in which the glaze film 2 is formed on the surface of the ceramic substrate 1 having an end face of 1R and then fired in an upright state.
A thin portion of the glaze film 2 or a portion in which the glaze film is not formed and the surface of the underlying ceramics is exposed occurs at the portion indicated by. This is because, before the glaze film is completely baked, the glaze film becomes thin at the boundary portion between the flat surface portion and the end surface portion of the ceramics substrate 1 due to the effect of the surface tension, and the glaze film is baked as it is, or a break occurs. is there. FIG. 4 shows an example in which a glaze film was similarly formed on the surface of the ceramics substrate 1 and then fired in a horizontal state. Due to the action of the surface tension of the glaze film and gravity, the glaze film is formed at a position indicated by an arrow B. Thin areas or cuts occur.

When a break occurs in the glaze film, the smoothness of the surface on which the wiring pattern is to be formed changes significantly, making it difficult to form the wiring pattern. That is, for example, when a wiring pattern is formed by photolithography, the photoresist remains at the cut portion, the pattern cannot be resolved, and the pattern is short-circuited at that portion.

An object of the present invention is to provide a method for manufacturing a glazed ceramics substrate, which enables a glaze film to be formed uniformly even near the end face of the ceramics substrate and a wiring pattern to be easily formed from the flat surface portion to the end surface portion of the ceramics substrate. To do.

(D) Means for Solving Problems The method for manufacturing a glaze ceramics substrate according to the present invention is a method in which a binder is mixed with ceramic powder to form a sheet, or the ceramic powder is formed into a plate and then calcined at a low temperature. To form a unglazed ceramics substrate, a step of coating the flat and end faces of this substrate with a glaze film, and a main baking of the entire substrate at a temperature higher than that at the time of pre-baking to bake the board and bake glazes. And the step of performing.

(E) Action In the method for producing a glaze ceramics substrate of the present invention, first, the binder is mixed with the ceramic powder to form a sheet, or the ceramic powder is formed into a plate, and then calcined to form a biscuit-like form. A ceramic substrate is formed. In the unglazed ceramics, crystal grains do not grow and there are many pores, so the wettability of the glaze is good, and the effect of the surface tension of the glaze is reduced. Therefore, when the ceramic substrate is coated with the glaze film, a uniform glaze film is formed from the flat surface portion to the end surface portion of the ceramic substrate. After that, the entire substrate is main-baked at a temperature higher than that at the time of pre-baking, so that the ceramic substrate is baked and the glaze is baked. This results in a structure in which the composition continuously changes from the ceramics to the glaze from the inside to the surface of the ceramics substrate.

(F) Example FIG. 1 shows a cross-sectional shape of a substrate manufactured by the method for manufacturing a glaze ceramics substrate which is an example of the present invention. In the figure, reference numeral 1 is a ceramics substrate such as alumina having a thickness of 3 mm and an end face portion of 1R, and a glaze 2 having a uniform film thickness is formed on the surface (plane and end face). The method of manufacturing such a glaze ceramic substrate is as follows.

After mixing the ceramic powder with a binder and forming it into a sheet, or after forming the ceramic powder into a plate, about 80
Pre-baking is performed at a relatively low temperature of 0 to 900 ° C. As a result, a bisque-fired ceramic substrate is formed.

On the surface of the substrate, a glass frit is kneaded with an organic resin and dried and a glaze tape is attached, or the entire substrate is dipped in a glaze bath to cover the glaze film.

The entire substrate is heated to about 1400 ° C for main firing. Since the glaze firing temperature is about 1200 to 1300 ° C., the firing of the substrate and the firing of the glaze are performed simultaneously.

An example in which the glaze ceramics substrate formed in this way is applied to an end face type thermal head used in a thermal printer or the like is shown in FIG. In the figure, 10 is a glaze ceramics substrate, and a plurality of heat generating parts are provided on the end face part thereof.
Wiring patterns of a common lead 12 and an individual lead 13 for supplying a driving current to the heat generating portion 11 are formed. In this way, it becomes possible to form a large number of wiring patterns with a fine pitch from the plane surface to the end surface of the ceramics substrate.

(G) Effects of the Invention As described above, according to the present invention, even when the glaze is formed on the entire outer surface of the ceramic substrate, a thin portion or a break of the glaze film is generated at the boundary portion between the flat portion and the end face portion of the substrate. It is possible to easily form a continuous wiring pattern from the flat surface portion to the end surface portion of the substrate.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing the shape of a substrate manufactured by the method for manufacturing a glaze ceramics substrate according to an embodiment of the present invention, and FIG. 2 is a partial perspective view showing the structure of an end face type thermal head using the same glaze ceramics substrate. FIG. 3, FIG. 3 and FIG. 4 are partial cross-sectional views showing the structure of a glaze ceramics substrate manufactured by a conventional method. 1 ... Ceramic substrate, 2 ... Glaze.

Claims (1)

[Claims] 1. A step of mixing a ceramic powder with a binder to form a sheet, or forming the ceramic powder into a plate, and then calcining the mixture at a low temperature to form a biscuit-like ceramic substrate, and the substrate. And a step of coating the glaze film on the flat surface and the end surface of the same, and a step of performing main baking of the entire substrate at a temperature higher than that at the time of pre-baking to perform baking of the substrate and baking of the glaze, the method for manufacturing a glazed ceramic substrate.