International Business Machines Corporation

Richard C Joy

Ingrid E Magdo

John L Mauer, Iv

Bernard M Kemlage

Alfred Phillips, Jr

James F Ziegler

Peter Burr

An integrated circuit structure having substrate contacts formed as a part of the isolation structure and the method to form such structure is described. The integrated circuit structure is composed of a monocrystalline silicon body having a pattern of dielectric isolation surrounding regions of the monocrystalline silicon in the body. The dielectric isolation pattern includes a recessed dielectric portion at and just below the surface of the integrated circuit and a deep portion which extends through the recessed dielectric portion and extends further into the monocrystalline silicon body than the recessed portion. A highly doped polycrystalline silicon substrate contact is located within the deep portion of the pattern of isolation. The substrate contact extends from the surface of the pattern of isolation down to the bottom of the deep portion of the isolation where the contact electrically connects to the silicon body. Any of a variety of integrated circuit device structures may be incorporated within the monocrystalline silicon regions. These devices include bipolar transistors, field effect transistors, capacitors, diodes, resistors and the like.

Isolation for high density integrated circuits

An integrated circuit structure having substrate contacts formed as a part of the isolation structure and method for making the same is described. The integrated circuit structure is composed of a monocrystalline silicon body having a pattern of dielectric isolation surrounding regions of the monocrystalline silicon in the body. The dielectric isolation pattern includes a recessed dielectric portion at and just below the surface of the integrated circuit and a deep portion which extends from the side of the recessed dielectric portion opposite to that portion at the surface of said body into the monocrystalline silicon body. A highly doped polycrystalline silicon substrate contact is located within the deep portion of the pattern of isolation. At certain locations the deep portion of the pattern extends to the surface of the silicon body where interconnection metallurgy can electrically contact the polycrystalline silicon so as to form a substrate contact to the bottom of the deep portion of the isolation where the contact electrically connects to the silicon body. Any of a variety of integrated circuit device structures may be incorporated within the monocrystalline silicon regions. These devices include bipolar transistors, field effect transistors, capacitors, diodes, resistors and the like.

An improved field effect transistor device in a monocrystalline semiconductor body provided with source and drain regions and a gate electrode disposed over the channel between the source and drain regions wherein at least the drain region is formed of a first region where the impurity concentration increases with depth with the peak concentration being spaced inwardly from the major surface, and a second region located within the first region having a peak impurity concentration at the major surface. The drain region structure in operation promotes the current flow between the source and drain to flow deeper in the channel region and spaced from the gate dielectric layer. In the method for forming the field effect transistor, an impurity is introduced into the semiconductor body underlying at least the ultimate drain region, an epitaxial semiconductor layer deposited, and a second impurity region formed over the first region to form the drain contact. In an alternate embodiment of the method for forming a field effect transistor, a first ion implantation is formed in the drain region, such that the peak impurity concentration is located well within the body spaced from the surface thereof, and a second ion implantation, or diffusion, performed forming the source and also the ohmic contact for the drain which is located over the first region and within the first implanted region.

Process of making field effect transistor having improved threshold

Epitaxial process for the fabrication of a field effect transistor

The device structure is a bi-polar transistor having a region of inert atoms located in the collector adjacent to the base-collector junction. Another embodiment of the invention is a complementary insulated gate field effect transistor (IGFET) structure having N and P channel IGFETs with regions of implanted ions beneath the source and drain of one or both transistors, and/or annular regions projecting inwardly from the surface that surround or separate the different types of IGFETs.

Growing community of inventors

Hopewell Junction, NY, United States of America

Richard C Joy