Method for implanting dopants within a substrate by tilting the substrate relative to the implant source

• US 20060073685A1
• Filed: 10/01/2004
• Published: 04/06/2006
• Est. Priority Date: 10/01/2004
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Xu, Jiejie, Ghneim, Said, Loewecke, Jeffrey, Robertson, Lance S., Bernstein, James D.
• Granted Patent: US 7,232,744 B2
• Time in Patent Office: Days
• US Class Current: 438/519
• CPC Class Codes: H01J 2237/31701 Ion implantation
• CPC Class Codes: H01L 21/26586 characterised by the angle between the ion beam and the crystal planes or the main crystal surface
• CPC Class Codes: H01L 21/823814 with a particular manufacturing method of the source or drain structures, e.g. specific source or drain implants or silicided source or drain structures or raised source or drain structures
• CPC Class Codes: Y10S 438/914 Doping

Abstract

The present invention provides a method for implanting a dopant in a substrate and a method for manufacturing a semiconductor device. The method for implanting a dopant, among other steps, including tilting a substrate (310) located on or over an implant platen (305) about an axis in a first direction with respect to an implant source (320) and implanting a portion of an implant dose within the substrate (310) tilted in the first direction. The method further includes tilting the substrate (310) having already been tilted in the first direction about the axis in a second opposite direction, and implanting at least a portion of the implant dose within the substrate (310) tilted in the second opposite direction.

Claims

1. A method for implanting a dopant in a substrate, comprising:

tilting a substrate located on or over an implant platen about an axis in a first direction with respect to an implant source, wherein the substrate has one or more patterned gate structures located thereover;

implanting a portion of an implant dose within the substrate and below the one or more patterned gate structures, the substrate tilted in the first direction;

tilting the substrate having already been tilted in the first direction about the axis in a second opposite direction; and

implanting at least a portion of the implant dose within the substrate and below the one or more patterned gate structures, the substrate tilted in the second opposite direction.

2. The method as recited in claim 1, further comprising:

rotating the substrate by about 90 degrees from its original position after implanting at least a portion of the implant dose within the substrate tilted in the second opposite direction;

tilting the rotated substrate about the axis a second time in the first direction;

implanting a portion of the implant dose within the substrate and below the one or more patterned gate structures, the substrate tilted in the first direction the second time;

tilting the substrate having already been tilted a second time in the first direction about the axis a second time in the second opposite direction; and

implanting a remaining portion of the implant dose within the substrate and below the one or more patterned gate structures, the substrate tilted in the second opposite direction the second time.

3. The method as recited in claim 2 wherein implanting a portion of an implant dose within the substrate tilted in the first direction includes implanting about ¼

of the implant dose, implanting at least a portion of the implant dose within the substrate tilted in the second opposite direction includes implanting about ¼

of the implant dose, implanting a portion of the implant dose within the substrate tilted in the first direction the second time includes implanting about ¼

of the implant dose, and implanting a remaining portion of the implant dose within the substrate tilted in the second opposite direction the second time includes implanting about ¼

of the implant dose.

4. The method as recited in claim 2 wherein rotating the substrate by about 90 degrees from its original position includes rotating the substrate by about 90 degrees in a clockwise direction from its original position.

5. The method as recited in claim 1 wherein tilting a substrate located on or over an implant platen about an axis in a first direction includes tilting a substrate located on or over an implant platen about an axis up to about 5 degrees in a first direction and tilting the substrate having already been tilted in the first direction about the axis in a second opposite direction includes tilting the substrate having already been tilted in the first direction about the axis up to about 5 degrees in a second opposite direction.

6. The method as recited in claim 1 wherein tilting a substrate located on or over an implant platen about an axis in a first direction includes tilting a substrate located on or over an implant platen about an axis from about 1 to about 3 degrees in a first direction and tilting the substrate having already been tilted in the first direction about the axis in a second opposite direction includes tilting the substrate having already been tilted in the first direction about the axis from about 1 to about 3 degrees in a second opposite direction.

7. The method as recited in claim 1 wherein angles of tilt in the first direction and the second opposite direction are substantially identical to an implant angle error in the implant source.

8. The method as recited in claim 1 wherein an angle of tilt in the first direction is substantially identical to an angle of tilt in the second opposite direction.

9. The method as recited in claim 1 wherein the substrate tilts about the axis in the platen in the first and second opposite direction.

10. The method as recited in claim 1 wherein the substrate is fixed in the platen and the platen tilts about the axis in the first and second opposite direction.

11. A method for manufacturing a semiconductor device, comprising:

forming a gate structure over a substrate; and

forming implants within the substrate below the gate structure, including;

tilting the substrate located on or over an implant platen about an axis in a first direction with respect to an implant source;

implanting a portion of an implant dose within the substrate tilted in the first direction;

tilting the substrate having already been tilted in the first direction about the axis in a second opposite direction; and

implanting at least a portion of the implant dose within the substrate tilted in the second opposite direction.

12. The method as recited in claim 11, wherein forming implants within the substrate proximate the gate structure further comprises:

rotating the substrate by about 90 degrees from its original position after implanting at least a portion of the implant dose within the substrate tilted in the second opposite direction;

tilting the rotated substrate about the axis a second time in the first direction;

implanting a portion of the implant dose within the substrate tilted in the first direction the second time;

tilting the substrate having already been tilted a second time in the first direction about the axis a second time in the second opposite direction; and

implanting a remaining portion of the implant dose within the substrate tilted in the second opposite direction the second time.

13. The method as recited in claim 12 wherein implanting a portion of an implant dose within the substrate tilted in the first direction includes implanting about ¼

of the implant dose, implanting at least a portion of the implant dose within the substrate tilted in the second opposite direction includes implanting about ¼

of the implant dose, implanting a portion of the implant dose within the substrate tilted in the first direction the second time includes implanting about ¼

of the implant dose, and implanting a remaining portion of the implant dose within the substrate tilted in the second opposite direction the second time includes implanting about ¼

of the implant dose.

14. The method as recited in claim 12 wherein rotating the substrate by about 90 degrees from its original position includes rotating the substrate by about 90 degrees in a clockwise direction from its original position.

15. The method as recited in claim 11 wherein tilting a substrate located on or over an implant platen about an axis in a first direction includes tilting a substrate located on or over an implant platen about an axis up to about 5 degrees in a first direction and tilting the substrate having already been tilted in the first direction about the axis in a second opposite direction includes tilting the substrate having already been tilted in the first direction about the axis up to about 5 degrees in a second opposite direction.

16. The method as recited in claim 11 wherein angles of tilt in the first direction and the second opposite direction are substantially identical to an implant angle error in the implant source.

17. The method as recited in claim 11 wherein an angle of tilt in the first direction is substantially identical to an angle of tilt in the second opposite direction.

18. The method as recited in claim 11 wherein the substrate tilts about the axis in the platen in the first and second opposite direction.

19. The method as recited in claim 11 wherein the substrate is fixed in the platen and the platen tilts about the axis in the first and second opposite direction.

20. The method as recited in claim 11 wherein implanting includes implanting at least a portion of source/drain extension implants.