Mitsubishi Denki Kabushiki Kaisha

Yasuo Kawashima

Seiji Oka

Satoshi Yanaura

Takeshi Muraki

In a method of manufacturing multi-layer printed wiring board, an uncured resin sheet is laminated on both surfaces of a printed wiring board having one or more layers, an organic cover film having a release property is laminated on the surfaces of the uncured resin sheets on upper and lower sides of the printed wiring board, a position of the printed wiring board is irradiated with a laser beam from the surface of the organic cover film to form a non-through hole that reaches a metal land for electrically conducting the layers of the inner printed wiring board, the non-through hole is filled with a thermosetting electrically conducting paste which is then half-cured, and the organic cover film is peeled off.

Method of manufacturing multi-layer printed wiring board

A method of manufacturing highly reliable and highly dense printed wiring board which is not warped even by the application of pressure and heat in manufacturing the multi-layer printed wiring board. The highly precise and highly dense multi-layer printed wiring board is realized by using an uncured resin sheet reinforced with fiber as an interlayer insulating layer, forming non-through holes in the uncured resin sheet using a laser beam, filling the non-through holes with a conductive paste, half-curing the conductive paste to form a wiring material, and sticking the wiring material onto the wiring substrate by application of pressure and heat, without causing a deviation in position even in applying pressure and heat.

Growing community of inventors

Tokyo, Japan

Yasuo Kawashima