US 2008/0290409 A1 · HALO-FIRST ULTRA-THIN SOI FET FOR SUPERIOR SHORT CHANNEL CONTROL

Abstract

Superior control of short-channel effects for an ultra-thin semiconductor-on-insulator field effect transistor (UTSOI-FET) is obtained by performing a halo implantation immediately after a gate reoxidation step. An offset is then formed and thereafter an extension implantation process is performed. This sequence of processing steps ensures that the halo implant is laterally separated from the extension implant by the width of the offset spacer. This construction produces equivalent or far superior short channel performance compared to conventional UTSOI-FETs. Additionally, the above processing steps permit the use of lower halo doses as compared to conventional processes.

Claims20

Dependent claims

A method of forming a semiconductor structure comprising:

forming a patterned gate stack atop a surface of an ultra-thin semiconductor-on-insulator (UTSOI) layer;
forming a disposable spacer on exposed vertical sidewalls of said patterned gate stack;
forming a raised source/drain region on an exposed first portion of said UTSOI layer;
removing said disposable spacer to expose a second portion of said UTSOI at a footprint of said patterned gate stack;
performing a halo ion implant into said exposed second portion of said UTSOI layer;
forming offset spacers on exposed sidewalls of said patterned gate stack and said raised source/drain region;
and
performing an extension ion implant into said second portion of said UTSOI layer that is not protected by said offset spacers.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application

11/753,862Filed 25 May 2007

Published

27 Nov 2008

Term ends

Not estimatedThe source records don’t support an estimate.

Classification7 codes

H10D 30/0275
Of lateral single-gate IGFETs: forming single crystalline semiconductor source or drain regions resulting in recessed gates, e.g. forming raised…
H10D 30/0323
Comprising silicon, e.g. amorphous silicon or polysilicon: comprising monocrystalline silicon
H10D 30/6715
Characterised by the properties of the source or drain regions, e.g. compositions or sectional shapes: characterised by the doping profiles, e.g.…
H10D 30/6737
Characterised by the electrodes: characterised by the electrode materials

Halo-first ultra-thin soi fet for superior short channel control

Life of this patent

Halo-first ultra-thin soi fet for superior short channel control

Life of this patent

Abstract

Claims20