US 12,408,362 B2
Method of forming devices with strained source/drain structures
Tsz-Mei Kwok, Hsinchu (TW); Hsueh-Chang Sung, Hsinchu (TW); Kuan-Yu Chen, Hsinchu (TW); and Hsien-Hsin Lin, Hsinchu (TW)
Assigned to AIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed on Jul. 13, 2022, as Appl. No. 17/864,033.
Application 17/864,033 is a division of application No. 15/910,701, filed on Mar. 2, 2018, granted, now 11,411,098.
Application 15/910,701 is a continuation of application No. 14/255,011, filed on Apr. 17, 2014, granted, now 9,911,826, issued on Mar. 6, 2018.
Application 14/255,011 is a continuation of application No. 13/009,322, filed on Jan. 19, 2011, granted, now 8,796,788, issued on Aug. 5, 2014.
Prior Publication US 2022/0352346 A1, Nov. 3, 2022
Int. Cl. H10D 30/01 (2025.01); H10D 30/60 (2025.01); H10D 30/69 (2025.01); H10D 62/00 (2025.01); H10D 62/822 (2025.01)
CPC H10D 30/0227 (2025.01) [H10D 30/0212 (2025.01); H10D 30/0275 (2025.01); H10D 30/608 (2025.01); H10D 30/797 (2025.01); H10D 62/021 (2025.01); H10D 62/822 (2025.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
etching a trench in a substrate adjacent to a gate structure, wherein the trench comprises a bottom surface and a tip portion extending under a spacer of the gate structure;
epitaxially growing a first semiconductor material in the trench, wherein the first semiconductor material covers an entirety of the bottom surface of the trench, and the first semiconductor material grows in the tip portion; and
epitaxially growing a second semiconductor material in the trench, wherein the second semiconductor material is different from the first semiconductor material, the second semiconductor material covers the first semiconductor material, and the second semiconductor material directly contacts the substrate between the bottom surface of the trench and the tip portion.