METHOD OF CREATING AN EXTREMELY THIN SEMICONDUCTOR-ON- INSULATOR (ETSOI) LAYER HAVING A UNIFORM THICKNESS

• US 20110097824A1
• Filed: 10/22/2009
• Published: 04/28/2011
• Est. Priority Date: 10/22/2009
• Status: Active Grant

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: BERLINER, Nathaniel C., La TULIPE, Douglas C. Jr., TONTI, William R., FURUKAWA, Toshiharu, CHENG, Kangguo
• Granted Patent: US 8,124,427 B2
• Time in Patent Office: Days
• US Class Current: 438/14
• CPC Class Codes: H01L 21/302 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

A method for creating an extremely thin semiconductor-on-insulator (ETSOI) layer having a uniform thickness includes: measuring a thickness of a semiconductor-on-insulator (SOI) layer at a plurality of locations; determining a removal thickness at each of the plurality of locations; and implanting ions at the plurality of locations. The implanting is dynamically based on the removal thickness at each of the plurality of locations. The method further includes oxidizing the SOI layer to form an oxide layer, and removing the oxide layer.

Claims

1. A method, comprising:

measuring a thickness of a semiconductor-on-insulator (SOI) layer at a plurality of locations;

determining a removal thickness at each of the plurality of locations;

implanting ions at the plurality of locations, wherein the implanting is dynamically based on the removal thickness at each of the plurality of locations;

oxidizing the SOT layer to form an oxide layer; and

removing the oxide layer.

2. The method of claim 1, wherein:

the oxide layer at a first location of the plurality of locations has a first thickness, and

the oxide layer at a second location of the plurality of locations has a second thickness different than the first thickness.

3. The method of claim 2, wherein:

the first thickness corresponds to a first determined removal thickness, and

the second thickness corresponds to a second determined removal thickness.

4. The method of claim 1, wherein the measuring comprises measuring a distance from an interface between the SOI layer and a buried insulator layer and a top of the SOI layer.

5. The method of claim 1, wherein the removal thickness at one of the plurality of locations is determined based on a difference between the measured thickness at the one of the plurality of locations and a final thickness of an extremely thin semiconductor on insulator (ETSOI) layer.

6. The method of claim 5, wherein the final thickness is a predetermined desired thickness of the ETSOI layer.

7. The method of claim 1, further comprising changing at least one of implantation dose and implantation energy between a first location of the plurality of locations and a second location of the plurality of locations.

8. The method of claim 7, wherein the changing at least one of the implantation dose and implantation energy causes the second location to have a second oxidation rate different than a first oxidation rate at the first location.

9. The method of claim 7, wherein the changing at least one of the implantation dose and implantation energy comprises changing a scan speed of an ion implant device.

10. The method of claim 7, wherein the changing at least one of the implantation dose and implantation energy is based on a first determined removal thickness and a second determined removal thickness.

11. The method of claim 1, wherein the oxidizing comprises oxidizing the SOI layer in a furnace.

12. The method of claim 1, wherein the removing the oxide layer comprises wet etching the oxide layer.

13. The method of claim 1, wherein the removing the oxide layer results in an ETSOI layer atop an insulator layer.

14. The method of claim 13, wherein the ETSOI layer has an average thickness of less than or equal to about 60 Å

.

15. The method of claim 14, wherein the ETSOI layer has a thickness variation of less than about +/−

6 Å

.

16. A method, comprising:

measuring a thickness of an SOI layer at a plurality of locations;

forming an oxide layer having in the SOI layer, wherein a thickness of the oxide layer varies based on the thickness of the SOI layer at the plurality of locations; and

removing the oxide layer, wherein after the removing a remaining portion of the SOI layer forms an ETSOI layer.

17. The method of claim 16, wherein the forming comprises:

implanting ions into the SOI layer, wherein the implanting comprises dynamically adjusting at least one of implantation dose and implantation energy at the plurality of locations based on the thickness of the SOI layer at the plurality of locations; and

oxidizing the SOI layer in a furnace.

18. The method of claim 17, wherein:

the ETSOI layer has'"'"' an average thickness of less than or equal to about 60 Å

, and

the ETSOI layer has a thickness variation of less than about +/−

6 Å

.

19. A system, comprising:

a measuring device configured to measure thickness of an SOI layer at a plurality of locations;

a processor configured to determine a removal thickness at each of the a plurality of locations;

an ion implant device configured to implant a species into the SOI layer at each of the plurality of locations, wherein at least one of implantation dose and implantation energy are adjusted based on the removal thickness at each of the plurality of locations;

an oxidation system configured to oxidize the SOI layer to form an oxide layer; and

an oxide removal system configured to remove the oxide layer.

20. The system of claim 19, wherein the removal thickness is based on a difference between the measured thickness and a desired final thickness of an ETSOI layer.