Japanese find copper paste saves space

Press, 4 February 1986, Page 28

Japanese find copper paste saves space

The Japanese search for yet tinier electronics equipment has turned up a spacesaving conductor, copper paste. Toshiba Corporation, a leading Tokyo-based electronics giant, has announced that it has developed the. paste as a conductive material in hybrid integrated circuit substrates.

Hybrid integrated circuits are multi-layed integrated circuits with alternating layers of conductive and insulating materials mounted on a ceramic substrate. The conductive layers carry transistors and resistors.

Toshiba says the paste will save space, the key to progress in consumer electronics. Until now hybrid integ-

rated circuits have been made with precious metal such as silver and platinum as the conductor. Toshiba claims the new paste will cut materials costs by half. Copper paste substrate layers will also serve as conductors for multiple layers of thin film resistors, but the paste has the drawback of being prone to oxidation. Toshiba says its process of first attaching the printed resistors to glass insulating layers, then depositing the copper past substrate, will beat this drawback. So far Toshiba has been able to attach two layers of printed resistors to the new substrate, but it believes it can attach as many as five—(New Zealand Japan News).