Patent ID: 11935793
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method comprising:
forming a source/drain region in a semiconductor fin, wherein forming the source/drain region comprises:
etching a recess in the semiconductor fin;
epitaxially growing a first epitaxy region in the recess;
in-situ doping the first epitaxy region with first impurities while epitaxially growing the first epitaxy region;
epitaxially growing a second epitaxy region in the recess and over the first epitaxy region; and
in-situ doping the second epitaxy region with second impurities while epitaxially growing the second epitaxy region, wherein the first impurities are a different element than the second impurities;

after forming the source/drain region, implanting third impurities into the source/drain region;
after implanting the first impurities, implanting fourth impurities into the source/drain region, wherein the third impurities have a lower formation enthalpy than the fourth impurities; and
after implanting the fourth impurities, annealing the source/drain region to define:
a first doped region doped with the third impurities; and
a second doped region doped with the fourth impurities, the third impurities of the first doped region extending along sides and below the fourth impurities of the second doped region.