Methods of forming semiconductor devices using embedded L-shape spacers

• US 7,759,206 B2
• Filed: 11/29/2005
• Issued: 07/20/2010
• Est. Priority Date: 11/29/2005
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation, Chartered Semiconductor Manufacturing Incorporated (Mamoura Diversified Global Holding PJSC)
• Original Assignee: International Business Machines Corporation, Chartered Semiconductor Manufacturing Incorporated (Mamoura Diversified Global Holding PJSC)
• Inventors: Ajmera, Atul C., Luo, Zhijiong, Teh, Young Way
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US11/164,567
• Publication Number:
  US 20070122988A1
• Time in Patent Office: 1,694 Days
• Field of Search: 438/142, 438/303, 438/305, 438/595, 257/E21.409, 257/E21.438, 257/E21.626, 257/E21.619
• US Class Current: 438/303
• CPC Class Codes: H01L 29/6653 using the removal of at least part of spacer, e.g. disposable spacer
• CPC Class Codes: H01L 29/6656 using multiple spacer layers, e.g. multiple sidewall spacers

Abstract

A method of forming a semiconductor device that embeds an L-shaped spacer is provided. The method includes defining an L-shaped spacer on each side of a gate region of a substrate and embedding the L-shaped spacers in an oxide layer so that the oxide layer extends over a portion of the substrate a predetermined distance from a lateral edge of the L-shaped spacer. And removing oxide layers to expose the L-shape spacers.

Claims

1. A method of forming a semiconductor device, comprising:

depositing a first oxide layer over a gate region and a semiconductor substrate;

depositing a nitride layer on said first oxide layer;

depositing a second oxide layer on said nitride layer;

etching said first oxide layer, said second oxide layer, and said nitride layer to form an L-shaped spacer on each side of said gate region;

depositing a third oxide layer on said L-shaped spacers so that said third oxide layer covers a portion of said semiconductor substrate a predetermined distance from a lateral edge of said L-shaped spacer;

etching said third oxide layer to reveal a top portion of said gate region and a top portion of said L-shaped spacer;

implanting ions in said substrate to define an implant region in said substrate at said predetermined distance from said lateral edge;

annealing said implant region to define a source-drain region, said source-drain region having an edge that is co-planar with said lateral edge;

removing said second and third oxide layers; and

forming a silicide region having an edge substantially co-planar to said lateral edge.

2. The method of claim 1, wherein said predetermined distance is up to about 600 Angstroms.

3. The method of claim 1, wherein said predetermined distance is between about 200 to about 400 Angstroms.

4. The method of claim 1, further comprising depositing a nitride stress layer over said silicide region, said L-shaped spacer, and said top portion of said gate region.

5. A method of forming a semiconductor device, comprising:

depositing a first L-shaped oxide layer on each side of a gate region of a semiconductor substrate;

depositing an L-shaped nitride layer on said first L-shaped oxide layer;

depositing a second oxide layer on said L-shaped nitride layer;

etching said first L-shaped oxide layer, said L-shaped nitride layer, and said second oxide layer to form an L-shaped spacer on each side of said gate region;

depositing a third oxide layer on said L-shaped spacers so that said third oxide layer covers a portion of said semiconductor substrate a predetermined distance from a lateral edge of said L-shaped spacer;

implanting ions in said substrate to define an implant region in said substrate at said predetermined distance from said lateral edge;

annealing said implant region to define a source-drain region having an edge that is co-planar with said lateral edge;

removing said second and third oxide layers; and

forming a silicide region having an edge substantially co-planar to said lateral edge.

6. The method of claim 5, further comprising etching said third oxide layer to reveal a top portion of said gate region and a top portion of said L-shaped spacer before implanting said ions.

7. The method of claim 5, wherein said predetermined distance is up to about 600 Angstroms.

8. The method of claim 5, wherein said predetermined distance is between about 200 to about 400 Angstroms.

9. A method of forming a semiconductor device, comprising:

forming an L-shaped spacer on each side of a gate region of a semiconductor substrate, said L-shaped spacer comprising a first oxide layer, a nitride layer, and a second oxide layer;

depositing a third oxide layer on said L-shaped spacers so that said third oxide layer covers a portion of said semiconductor substrate a predetermined distance from a lateral edge of said L-shaped spacer; and

implanting ions in said substrate to define an implant region in said substrate at said predetermined distance from said lateral edge;

annealing said implant region to define a source-drain region having an edge that is co-planar with said lateral edge;

removing said second and third oxide layers;

forming a silicide region having an edge substantially co-planar to said lateral edge; and

depositing a nitride stress layer over said silicide region, said spacer, and said top portion of said gate region.