JPS60134498A - Method of producing electronic part - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to a method of manufacturing an electronic component in which chip components, mini-flat ICs, etc. are mounted on a base substrate made of ceramic, M-material, etc. be.

(b) Background of the technology Electronic components include passive components such as chip resistors, capacitors, and ICs on base substrates on which circuits are formed using various manufacturing methods such as vapor deposition, printing, and etching.

After 7'C after mounting the active parts, undercoating with liquid silicone resin is applied with resin such as silicone or epoxy to provide full moisture resistance and impact resistance, although the coating method and structure of the outer coating differ depending on the exterior coating etc. In many cases, a so-called 2M structure is used, in which the final exterior is covered with epoxy resin.

(C) Deforestation and Problems Figure 1 is a diagram showing an outline of the process of the conventional double exterior coating method.

First, various parts are mounted on the base. Next, the silicone material, a curing agent that hardens the silicone, a catalyst that increases the adhesion of the silicone to the base substrate, and a solvent called xylene that adjusts the viscosity during painting are mixed together, and all of this coating material is mixed. Exterior coating is carried out by spraying onto the base substrate on which the product is mounted.Next, in order to evaporate the xylene mixed as a coating material on the entire exterior coated base substrate, it is kept in an atmosphere at a temperature of approximately 70°C for approximately 2 hours. dry.

Next, the base board coated with the exterior coating is held in an atmosphere at a temperature of about 70°C for more than 2 hours, and the air remaining between the bottom parts between the mounted parts and the xylene mixed as a coating material are discharged. Evaporate.

Next, the dried base substrate is held in an atmosphere at a temperature of about 150° C. for about 1 hour or more, and a heat treatment for curing the silicon main material and the like is performed.

After the heat treatment has been completed, the base board is coated with a final exterior coat of epoxy resin to complete the manufacturing of the electronic component.

Therefore, in the conventional electronic component manufacturing method described above,
It takes a lot of time to heat treatment after the exterior coating, and during the drying or heat treatment process, the air trapped at the bottom of the mounted parts and between the S parts and the volatile solvent cytelene are released one after another, causing the pins to burn out. In addition, even if it does not eject to the bottom surface, it stagnates within the resin film and becomes a porous cured film. Hence the desired moisture resistance.

Figure 2 has the disadvantage of not being able to provide impact resistance.
Fig. 3(a) is a diagram showing a state in which an exterior coating has been applied to a base board on which components are mounted; (a) is a diagram showing a state in which air remains between one component at the bottom of the mounted component; FIG. 2 is a diagram showing a state in which a pinhole has occurred.

In the figure, 1 is a plate mounted on the base, 2 is a component mounted on the base substrate 1, 3 is a lead wire, 4 is a silicone resin covering the base substrate 1 and the components 2, and 5 is the bottom of the bar 6 product 2. Air remaining between the parts, 6 indicates a pinhole.

Although we had repeatedly carried out 100% inspection and pinhole repair work on the exterior coated base substrate 1 before and after the heat curing process, it was not perfect, and inspection 1. fc has the disadvantage that pinholes occur after the final exterior (powder coating) due to repair leakage, etc., which affects the product yield.

(d) Purpose of the Invention The purpose of the invention is, in view of the above-mentioned drawbacks of the conventional technology, to obtain desired moisture resistance and impact resistance without trapping pinholes or air between parts during the heat curing process. The object of the present invention is to realize a method for manufacturing electronic components that can increase the product yield and thereby increase the product yield. manufacturing an electronic component, comprising the steps of: coating a substrate with a resin; holding the substrate coated with the resin in a vacuum atmosphere for a predetermined time; and curing the resin coating the substrate. This is accomplished by a method.

(Examples of the invention) Examples of the method of manufacturing electronic components according to the invention will be described in detail below. Fig. 3 is an example of the method of manufacturing electronic components according to the invention. The difference from the conventional electronic component manufacturing method shown in FIG. 1 is that the drying step is eliminated and the thermosetting step is performed in a vacuum atmosphere9.

In other words, the exterior coating is carried out by spraying the coating material onto the base board on which all the components are mounted, and then heat curing treatment is performed in a vacuum atmosphere to remove the volatile solvent contained in the coating material. The heat curing process can be performed in a state where a certain amount of styrene is discharged and air remaining at the bottom of the parts mounted on the base substrate and between the parts is completely discharged.

According to this example, not only a dense and high-quality cured film with no voids (cavities) can be obtained, but also the pinhole inspection, repair work, and drying work required in the conventional process are no longer required. This has the effect of improving the reliability of the module and significantly reducing the number of man-hours.

In this example, we will explain the case where the thermosetting treatment is carried out in a vacuum atmosphere. The entire heat curing process may be performed after removing the remaining air.

(No) As described in detail, according to the present invention, desired moisture resistance and impact resistance can be achieved, thereby improving the product yield of electronic components.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of a conventional method for manufacturing electronic components, Figure 2 is a diagram showing a state in which an exterior coat is applied to a base board on which components are mounted, and Figure 3 is a diagram illustrating the manufacturing method of electronic components according to the invention. In the figure U, which is a diagram illustrating an example of the method, 1 is a base substrate, 2 is a component, 3 is a lead wire, 4 is a silicone resin, 5 is a gas hole, and 6 is a pinhole. , Ehito Patent Attorney Iyu Matsuoka■

Claims (1)

[Claims] (υ A step of coating a resin on a board on which a plurality of parts are mounted, a step of holding the resin-coated board in a vacuum atmosphere for a predetermined time, and a step of curing the resin covering the board. 0(2) A method for manufacturing an electronic component, characterized in that the step of holding the substrate in a vacuum atmosphere and the step of curing the resin are performed simultaneously. Manufacturing method for electronic components described in (1) 0