Sony Chemicals Corporation

Sony Corporation

Mitsuhiro Fukuda

Hideyuki Kurita

Masanao Watanabe

Masayuki Nakamura

Toshihiro Shinohara

Yukio Anzai

Hiroyuki Usui

The multilayer flexible wiring board includes first and second patterned wiring layers, a resin film interposed between a surface of the first wiring layer and a surface of the second wiring layer, and a bump connected to the surface of the second wiring layer. The resin film is adapted to form an opening when the bump is forced into the resin film and an ultrasonic wave is applied to the bump. The bump is left in the opening to electrically connect the top of the bump to the first wiring layer.

Process for manufacturing multilayer flexible wiring boards

The present invention pertains to a multilayer flexible wiring board. The multilayer flexible wiring board including first and second patterned wiring layers, a resin film interposed between a surface of the first wiring layer and a surface of the second wiring layer, and a bump connected to the surface of the second wiring layer, wherein the resin film is adapted to form an opening when the bump to force into the resin film and an ultrasonic wave is applied to the bump and the bump is left in the opening to electrically connect the top of the bump to the first wiring layer.

Ultrasonic manufacturing apparatus

A board pieceof the present invention comprises a non-thermoplastic resin film, a thermoplastic resin filmformed on the non-thermoplastic resin filmand a metal wiringformed on the surface of the thermoplastic resin film. Metal wiringis partially exposed on board pieceto form a contact. A low-melting metal coatingis formed on contactand two board piecesare pressed against each other under heating with contactsthereof being in contact with each other so that thermoplastic resin filmssoften to adhere board piecesto each other and low-melting metal coatingsmelt and then solidify to connect contactsto each other. The region of metal wiringnot used for connection is wiringconnecting contactsto each other and a cover filmcan be provided on the surface thereof. Contactscan also be connected by applying ultrasonic wave.

Board pieces, flexible wiring boards and processes for manufacturing flexible wiring boards

A board piece of the present invention comprises a non-thermoplastic resin film , a thermoplastic resin film formed on the non-thermoplastic resin film and a metal wiring formed on the surface of the thermoplastic resin film . Metal wiring is partially exposed on board piece to form a contact . A low-melting metal coating is formed on contact and two board pieces are pressed against each other under heating with contacts thereof being in contact with each other so that thermoplastic resin films soften to adhere board pieces to each other and low-melting metal coatings melt and then solidify to connect contacts to each other. The region of metal wiring not used for connection is wiring connecting contacts to each other and a cover film can be provided on the surface thereof. Contacts can also be connected by applying ultrasonic wave.

Board pieces, flexible wiring boards, and processes for manufacturing flexible wiring boards

Ultrasonic manufacturing apparatuses, multilayer flexible wiring boards and processes for manufacturing multilayer flexible wiring boards

This invention provides a specially-shaped, double-face flexible printed wiring board having a small pitch at a high production yield. Metal wirings and formed on a base film of two elemental pieces and of a flexible printed wiring board are arranged in such a manner as to face each other while sandwiching a bonding film not containing conductive particles between them, and are heat-pressed to each other. The adhesive resin film so softened is pushed aside from the metal wirings and and the low melting point metal coating films and formed on the surface of the metal wirings and come into direct contact with each other and are fused. In this instance, the softened adhesive resin film is charged between the metal wirings and . Therefore, the molten low melting point metal does not scatter. The base films and are bonded by the adhesive resin film

Growing community of inventors

Kanuma, Japan

Mitsuhiro Fukuda