JPS5815959B2 - Method for manufacturing transparent laminated wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a transparent laminated wiring board, and in particular, a transparent laminated wiring board suitable for mounting display elements such as light emitting diodes (LEDs), liquid crystals (LCDs), and electroluminescence (EL). Relating to a manufacturing method.

Conventionally, the laminated wiring board is generally a plastic-copper-clad wiring board or a ceramic-metallized wiring board.

These wiring boards have appropriate characteristics, but since they are opaque, LEDs require transparency.

It was not suitable for mounting display elements such as LCD, EI, and ECD (electrochromic display).

Therefore, an object of the present invention is to provide a transparent laminated wiring board suitable for mounting display elements, and also to provide a relatively low-cost manufacturing method for a laminated wiring board with good manufacturability and high reliability. .

Embodiments of the manufacturing method according to the present invention will be described in detail below with reference to the drawings.

1 to 5 are explanatory diagrams for explaining the method of manufacturing a laminate of the present invention, in which 1 is a transparent glass substrate or a transparent ceramic substrate, 2.2' is a transparent indium oxide-based conductive coating, and 3 is a transparent indium oxide-based conductive coating. The silicon oxide plate film 4 is a low melting point glass layer based on lead oxide and zinc oxide.

Example 1 Step 1; Transparent glass substrate or transparent ceramic substrate 1
A transparent indium oxide conductive film 2 is formed on the entire surface or a portion thereof by vacuum evaporation or sputtering (FIG. 1).

Step 2: Next, an organic silicon compound, such as ethyl orthosilicate, is uniformly deposited on the required part of the upper surface of the conductive film 2, and this is thermally decomposed at around 500°C to form a silicon oxide film 3 of about 1000 or less. (Figure 2).

Step 3: Subsequently, a lead oxide/zinc oxide based low melting point glass layer 4 is formed on the silicon oxide plate film 3 and at appropriate locations on the conductive film to be removed.

The low melting point glass layer 4 is formed by a screen printing method using a paste ink obtained by uniformly mixing glass frit, ethyl cellulose, and an organic solvent (FIG. 3).

Step 4: Next, the low melting point glass coating 4 is heated to about 400 to 500°C.

As a result, the portion a (third
(Fig.) changes and the conductive coating 2 changes to the low melting point glass coating 4.
It dissolves and disappears, becoming a nonconductor.

On the other hand, the above-mentioned changes do not occur in the conductive film in the portions c and d (Fig. 3) where the silicon oxide (Sin2) film 3 of the intermediate layer is formed, and the conductive film does not become non-conductive ( The fourth step completes the necessary circuit patterning and the protection and insulation of the conductive film 2.

Step 5: Thereafter, the transparent indium oxide-based conductive film 2' is similarly formed on the entire surface or at necessary locations (Fig. 5), and the above steps are repeated to create the required number of layers of the transparent laminated wiring board. According to Example 1, pattern selectivity is easy;
In addition, each layer can be laminated reliably, the conductor film can be insulated and protected, and a transparent laminated wiring board can be provided at a relatively low cost.

Example 2 Step 1: An organic indium paste is deposited on a substrate 1 by screen printing and thermally decomposed at around 500° C. to form a conductive film 2 (FIG. 1).

According to this method, pattern formation can be performed more easily than when using sputtering or vapor deposition methods.

Note that the steps after step 2 are the same as in the first embodiment.

Example 3 Instead of the organosilicon compound in Step 2 of Example 1, an organotitanium compound was uniformly deposited on the necessary portions of the upper surface of the conductive film 2, and was thermally decomposed to form titanium oxide TiO2.

Note that steps 1, 3 and 4.5 are the same as in the first embodiment.

In this Example 3, the substrate was colored yellowish brown, and a colorless and transparent laminated substrate could not be obtained.

Example 4 In step 3 of Example 1, a low melting point glass layer 4 is formed on the silicon oxide film 3 and the conductive films 2, 2/ to be removed. (54
0°C), 2nd layer (500°C), 3rd layer (480°C), 4th layer
A transparent laminated wiring board was prepared by heating the upper layer (at 450° C.) and lowering the temperature toward the upper layer.

Note that a soda glass substrate was used as the substrate 1. In order to make a transparent wiring board multi-layered, it is necessary to insulate each layer with low melting point glass 4, but if the melting point of the low melting point glass is made the same for all layers, when creating a pattern for the (i+1)th layer, (
Step 4) The conductive coating 2/ of the layer is applied to the first layer (i-1, 2
(...) That is, the lower layer low melting point glass 4 may be melted by heating and melting, making it impossible to create a good transparent wiring board.

However, according to Example 4, since the melting point of the low-melting glass is lower as it goes to the upper layer, the heating temperature in step 4 can be lowered as it goes to the upper layer. It will not be eaten by low melting point glass.

Similarly, the melting point difference was required to be at least 20°C.

Example 5 A transparent laminated wiring board was prepared by adding the following process as step 4' to step 4 and subsequent steps of example 1.

Step 4': An organic silicon compound is deposited on the low melting point glass layer 4, and this is thermally decomposed at about 500'C to form a silicon oxide film 3' of about 100 OA or less (FIG. 6).

Thereafter, steps 1 to 4' were repeated to produce a transparent laminated wiring board.

. That is, in Example 5, a transparent laminated wiring board was prepared by sandwiching an intermediate conductive film 2 and a silicon oxide film 3.

In the case of Example 4, the melting point difference of the low melting point glasses was sequentially increased by 20°C.
There is a limit to the number of laminated layers because the melting point has to be lowered step by step, but in the case of Example 5, there is no limit to the number of laminated layers because the melting points of each low melting point glass 4 can be made the same.

As described above, according to the present invention, it is possible to provide a transparent laminated wiring board that is suitable for mounting display elements, has high reliability, that is, has good insulation properties, protection properties, etc., and has good manufacturability.

[Brief explanation of drawings]

FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. 6 are explanatory diagrams illustrating each step of the method for manufacturing a transparent laminated wiring board according to the present invention. 1...Transparent glass substrate or transparent ceramic substrate, 2.2'...Transparent indium oxide conductive coating, 3゜31...100% X, X old ■Yi A,,,,,,to the left Acidite lead-based low melting point glass layer.

Claims (1)

[Claims] 1. An indium oxide-based transparent conductive film is formed entirely or partially on the upper surface of a heat-resistant transparent insulating substrate, and an organosilicon compound is thermally decomposed on the necessary portions of the upper surface to form silicon oxide. A film is applied, a low melting point glass material is further covered on the necessary parts of the upper surface, the conductive film is removed from unnecessary parts by heating and melting, and then the above process is repeated to form a transparent laminated wiring board. A method for manufacturing a transparent laminated wiring board, the method comprising: manufacturing a transparent laminated wiring board. 2. The method of manufacturing a transparent laminated wiring board according to claim 1, wherein the melting point of the low melting point glass of each of the laminated layers is lowered in the order of lamination. 2. The method of manufacturing a transparent laminated wiring board according to claim 1, wherein the indium oxide-based transparent conductive film from the 32nd layer onward is sandwiched between silicon oxide films.