Inmos Limited

United Technologies Corporation

James R Adams

Gary F Derbenwick

Matthew Hanson

William Dennis Ryden

Alfred P Gnadinger

James C Weaver

Polycrystalline silicon resistors are formed by reducing the initial thickness of a poly layer to a magnitude such that the etch end point of the lightly doped resistors is equal to the etch end point of the heavily doped interconnection.

Thin polysilicon resistors

The invented technique permits the gate length to equal the channel length: source/drain regions are self-aligned and non-overlapping with respect to their gate electrode. The non-overlapping feature, along with other optimized device characteristics, are generally provided by defining a gate electrode over a substrate, forming an implant mask of dielectric, for example, on the sides of the gate electrode, and implanting a source/drain region such that the implant mask shields a portion of the substrate from implantation to provide a gap between a side edge of the gate electrode and the implanted regions. The source/drain region is then heat driven until its side edge is substantially aligned with the edge of the gate electrode. Self-aligned source/drain contacts are also provided using the implant mask to isolate the gate electrode from the contacts and interconnects.

Zero drain overlap and self aligned contact method for MOS devices

A method is described for fabricating MOS devices of the type found in very large scale integrated circuits. According to the method described herein, various gate oxides and insulating layers are fabricated independently of each other in order to independently tailor their thicknesses and thereby provide improved isolation between gate electrodes and interconnects, and independently controllable operating characteristics for multiple gate electrode structures. The fabrication of a dynamic RAM memory cell, an overlapping gate CCD device and a self-aligned MNOS transistor cell are described using the disclosed method.

Growing community of inventors

Colorado Springs, CO, United States of America

James R Adams