METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

• US 20090317950A1
• Filed: 06/19/2009
• Published: 12/24/2009
• Est. Priority Date: 06/24/2008
• Status: Active Grant

• Current Assignee: LAPIS Semiconductor Co., Ltd. (ROHM Co., Ltd.)
• Original Assignee: Oki Semiconductor Company Limited (ROHM Co., Ltd.)
• Inventors: OKIHARA, Masao
• Granted Patent: US 7,985,638 B2
• Time in Patent Office: Days
• US Class Current: 438/151
• CPC Class Codes: H01L 21/28052 the conductor comprising a silicide layer formed by the silicidation reaction of silicon with a metal layer formed by metal ion implantation H01L21/28044
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/458 for thin film silicon, e.g. source or drain electrode
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/4975 being a silicide layer, e.g. TiSi2
• CPC Class Codes: H01L 29/665 using self aligned silicidation, i.e. salicide formation of conductive layers comprising silicides H01L21/28518
• CPC Class Codes: H01L 29/6653 using the removal of at least part of spacer, e.g. disposable spacer

Abstract

A semiconductor device manufacturing method which sequentially forms a gate oxide film and gate electrode material over a semiconductor layer of an SOI substrate and patterns the material into gate electrodes. The method further comprises the steps of forming sidewalls made of an insulator to cover side surfaces of the gate electrode; ion-implanting into the semiconductor layer on both sides of the gate electrode to form drain/source regions; partially etching the sidewalls to expose upper parts of the side surfaces of the gate electrode; depositing a metal film to cover the tops of the drain/source regions and of the gate electrode and the exposed upper parts of the side surfaces of the gate electrode; and performing heat treatment on the SOI substrate to form silicide layers respectively in the surfaces of the gate electrode and of the drain/source regions.

Claims

1. A semiconductor device manufacturing method which forms a MOSFET in an SOI substrate having an insulating layer between a semiconductor substrate layer and a semiconductor layer, said method comprising the steps of:

forming a gate oxide film over said semiconductor layer;

forming a gate electrode on said gate oxide film;

forming sidewalls made of an insulator to cover side surfaces of said gate electrode;

ion-implanting into said semiconductor layer on both sides of said gate electrode to form drain/source regions in said semiconductor layer;

partially etching said sidewalls to expose upper parts of the side surfaces of said gate electrode;

depositing a metal film to cover the tops of said drain/source regions and of said gate electrode and the exposed upper parts of the side surfaces of said gate electrode; and

performing heat treatment on said SOI substrate to form silicide layers respectively in the surfaces of said gate electrode and of said drain/source regions.

2. A semiconductor device manufacturing method according to claim 1, further comprising the step of:

before said metal film depositing step, forming a plurality of grooves in the top of said gate electrode.

3. A semiconductor device manufacturing method according to claim 2, wherein in said metal film depositing step, each of said plurality of grooves is filled with said metal film.

4. A semiconductor device manufacturing method according to claim 1, wherein said gate electrode forming step comprises the step of forming a poly-silicon film having bumps and hollows on its surface.

5. A semiconductor device manufacturing method according to claim 4, wherein said poly-silicon film is a HSG film.

6. A semiconductor device manufacturing method according to claim 1, wherein said metal film has isotropic step coverage.

7. A semiconductor device manufacturing method according to claim 1, wherein said metal film is a cobalt film.