Digital Equipment Corporation

Trilogy Computer Development Partners, Ltd.

Chune Lee

James C Lee

Richard L Beck

Edward Hu

John William Sliwa

Gene M Amdahl

Francisca Tung

Roy J Burt

Arshad Ahmad

Myrna E Castro

Cindy A Johnson

John MacKay

A method of forming a multilayer circuit board is disclosed which includes a build-up process in which, beginning with a solidified layer of the dielectric disposed upon a substrate, alternate layers of conducting metal and dielectric are sequentially deposited. Each layer of conducting metal lines is defined using photoresist and a photolithographic technique. After the lines are deposited, the photoresist is removed and a second layer of photoresist defines the conductive posts which function as through holes between metal layers. After each layer of conductive line and posts is formed, and the photoresist is removed, the dielectric is flowed into place and solidified to insulate adjacent metal lines and posts. The process may be repeated as many times as necessary to build up layers of conducting metal and dielectric, and form the completed multilayer wiring board.

Sequential multilayer process for using fluorinated hydrocarbons as a

A semiconductor mounting system is provided for the detachable surface mounting of one or more semiconductor dies on a conductor substrate, such as a ceramic substrate or printed circuit board. The system employs a resilient, anisotropic conductor pad which is interposed between the semiconductor die and the conductor substrate. The conductor pad is capable of conducting electric signals in one direction only, and insulates in the other two orthogonal directions. Thus, by compressing the semiconductor die and resilient conductor pad against the conductor substrate, electrical contact is established between contacts on the semiconductor die and corresponding contacts on the conductor substrate. In the preferred embodiment, additional conductor pads are placed over the semiconductor dies, and a heat sink placed over the second conductor pads. In this way, the semiconductor dies are mounted in a resilient structure for protection, while heat dissipation is enhanced by the metallic elements in the second conductor pad.

System for detachably mounting semiconductors on conductor substrate

An anisotropic elastomeric conductor is fabricated by stacking a plurality of first and second sheets, where the first sheets include a plurality of parallel electrically conductive fibers and the second sheets are composed of electrically insulating material. By introducing a curable elastomeric resin into the layered structure of sheets, and then curing the resin, a solid elastomeric block having a plurality of parallel electrically conductive fibers running its length is obtained. Individual elastomeric conductors suitable for interfacing between electronic components are obtained by slicing the block in a direction perpendicular to the conductors. The conductor slices so obtained are particularly suitable for interfacing between electronic devices having planar arrays of electrical contact pads.

Electrical connector for surface mounting

Electronic assemblies are fabricated by stacking alternate connecting layers and component layers. The component layers may be virtually any rigid structure having contact regions formed on at least one face thereof. The connecting layers are formed from anisotropic elastomeric conductors which in turn are fabricated by stacking a plurality of conductive sheets and insulating sheets, where the conductive sheets have a plurality of parallel electrically conductive elements formed therein. By introducing a curable elastomeric resin into the stacked structure so formed, and then curing the elastomer, a solid elastomeric block having a plurality of parallel electrically conductive elements running its length is obtained. Individual elastomeric conductors suitable as connecting layers interfacing between adjacent component layers are obtained by slicing the block in a direction perpendicular to the conductors.

Anisotropic elastomeric interconnecting system

An anisotropic elastomeric conductor is fabricated by stacking a plurality of metal sheets and elastomeric sheets, where the metal sheets have a plurality of parallel electrically conductive elements formed therein. By coating a curable elastomeric resin on the metal sheets, and then curing the resulting layered structure, a solid elastomeric block having a plurality of parallel electrically conductive elements running its length is obtained. Individual elastomeric conductors suitable for interfacing between electronic components are obtained by slicing the block in a direction perpendicular to the conductors. The conductor slices so obtained are particularly suitable for interfacing between electronic devices having planar arrays of electrical contact pads.

Electrical connector for surface mounting and method of making thereof

Method of fabricating electrical connector for surface mounting

A method of attaching a semiconductor chip to a mounting surface is disclosed. A solder barrier is applied to the mounting surface, and a preform of solder is located within the solder barrier. The preform is heated and then cooled in a vacuum to preflow the solder and secure the solder to the mounting surface substantially without voids. The semiconductor chip is then placed over the preflowed solder, which is reheated and then recooled in a vacuum to secure the chip to the mounting surface.

Growing community of inventors

San Francisco, CA, United States of America

Chune Lee