Laser anneal process

Patent metadata

Field	Value
Publication number	US-10867809-B2
Application number	US-201815996254-A
Country	US
Kind code	B2
Filing date	Jun 1, 2018
Priority date	Nov 22, 2017
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A method of forming a semiconductor device includes forming a doped region on a semiconductor substrate, in which the doped region comprises an impurity therein, and performing a laser anneal process to the doped region with a process gas containing a dopant gas, in which the dopant gas and the impurity comprise the same chemical element.

First claim

What is claimed is:

1. A method comprising:
forming a doped region on a semiconductor substrate with a first process gas having a dopant gas, wherein the doped region comprises an impurity therein; and
performing a laser anneal process to the doped region with a second process gas having the dopant gas, wherein the dopant gas and the impurity comprise the same chemical element, and a partial pressure of the dopant gas during forming the doped region is less than a partial pressure of the dopant gas during the laser anneal process.

2. The method of claim 1 , wherein the laser anneal process is performed under a process pressure greater than about 1 atm.

3. The method of claim 1 , further comprising:
introducing the dopant gas into a chamber where the semiconductor substrate is, such that the partial pressure of the dopant gas in the chamber increases.

4. The method of claim 1 , further comprising:
reducing a volume of a chamber where the semiconductor substrate is, such that the partial pressure of the dopant gas in the chamber increases.

5. The method of claim 1 , further comprising:
raising a temperature in a chamber where the semiconductor substrate is, such that the partial pressure of the dopant gas in the chamber increases.

6. The method of claim 1 , wherein the partial pressure of the dopant gas during the laser anneal process is in a range from about 1E-1 torr to about 10 torr.

7. The method of claim 1 , wherein the dopant gas comprises n-type dopants.

8. The method of claim 1 , wherein the doped region comprises Si, Ge, or combinations thereof.

9. A method comprising:
introducing a dopant gas into a chamber;
forming a doped source/drain region on a semiconductor substrate; and
performing a laser anneal process on the doped source/drain region under a process pressure greater than about 1 atm, wherein the laser anneal process is performed in the chamber, and a partial pressure of the dopant gas during the laser anneal process is in a range from about 1E-1 torr to about 10 torr.

10. The method of claim 9 , wherein the doped source/drain region has an impurity therein, and the dopant gas and the impurity comprise the same chemical element.

11. The method of claim 9 , wherein a partial pressure of a dopant during forming the doped source/drain region is less than the partial pressure of the dopant gas during the laser anneal process.

12. The method of claim 9 , further comprising:
reducing a volume of the chamber where the laser anneal process is performed prior to, during, or both prior to and during the laser anneal process.

13. The method of claim 9 , further comprising:
raising a temperature in the chamber where the laser anneal process is performed prior to, during, or both prior to and during the laser anneal process.

14. A method comprising:
forming source/drain regions on a substrate in a chamber;
introducing a dopant gas above the source/drain region in the chamber, wherein the dopant gas comprises gas-phase dopants therein;
stopping the introducing of the dopant gas, then increasing a partial pressure of the gas-phase dopants in the chamber; and
annealing the source/drain regions by a laser through the gas-phase dopants.

15. The method of claim 14 , wherein increasing the partial pressure of the gas-phase dopants comprises:
increasing a number of moles of the gas-phase dopants in the chamber.

16. The method of claim 14 , wherein increasing the partial pressure of the gas-phase dopants comprises:
decreasing a volume of the chamber.

17. The method of claim 16 , wherein decreasing the volume of the chamber comprises:
lifting a stage in the chamber, wherein the substrate is on the stage.

18. The method of claim 14 , wherein increasing the partial pressure of the gas-phase dopants comprises:
increasing a temperature of the chamber.

19. The method of claim 14 , wherein increasing the partial pressure of the gas-phase dopants in the chamber is performed prior to annealing the source/drain regions.

20. The method of claim 14 , wherein annealing the source/drain regions by the laser is performed under the increased partial pressure of the gas-phase dopants.

Assignees

• Taiwan Semiconductor Mfg Co Ltd
• Univ Nat Taiwan

Inventors

• Lu Chun-Ti
• Lee Meng-Chin
• Lu Fang-Liang
• Liu Chee-Wee

Classifications

• H10P72/0436

  mainly by radiation · CPC title

• H10P34/42

  with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) · CPC title

• H10P95/902 Primary

  for the formation of PN junctions without addition of impurities · CPC title

• H10P32/171

  being group IV material · CPC title

• H10P32/12

  between a solid phase and a gaseous phase · CPC title