Patent ID: 11949016
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC H

Claim 17:
18. A method, comprising:
forming a first source/drain feature in a first device region, wherein the first source/drain feature includes a first bottom region and a first top region; and
performing a first doping process to the first source/drain feature, wherein the first doping process introduces a first dopant species in the first bottom region and a second dopant species in the first top region, and wherein the first dopant species has a first graded doping profile and the second dopant species has a second graded doping profile;
forming a second source/drain feature in a second device region, wherein the second source/drain feature includes a second bottom region and a second top region; and
performing a second doping process to the second source/drain feature, wherein the second doping process introduces the first dopant species in the second bottom region and a third dopant species in the second top region, and wherein the first dopant species has the first graded doping profile and the third dopant species has a third graded doping profile.