US 11,721,746 B2
Method and structure for FinFET comprising patterned oxide and dielectric layer under spacer features
Che-Cheng Chang, New Taipei (TW); Jr-Jung Lin, Hsinchu (TW); Shih-Hao Chen, Hsinchu County (TW); Chih-Han Lin, Hsinchu (TW); Mu-Tsang Lin, Changhua County (TW); and Yung Jung Chang, Hsinchu County (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsin-Chu (TW)
Filed on Aug. 17, 2020, as Appl. No. 16/995,401.
Application 16/995,401 is a continuation of application No. 16/525,348, filed on Jul. 29, 2019, granted, now 10,749,014.
Application 16/525,348 is a continuation of application No. 15/674,117, filed on Aug. 10, 2017, granted, now 10,367,079, issued on Jul. 30, 2019.
Application 15/674,117 is a continuation of application No. 14/799,057, filed on Jul. 14, 2015, granted, now 9,735,256, issued on Aug. 15, 2017.
Claims priority of provisional application 62/065,149, filed on Oct. 17, 2014.
Prior Publication US 2020/0381532 A1, Dec. 3, 2020
Int. Cl. H01L 29/66 (2006.01); H01L 21/762 (2006.01); H01L 29/78 (2006.01); H01L 21/311 (2006.01)
CPC H01L 29/6681 (2013.01) [H01L 21/31116 (2013.01); H01L 21/76224 (2013.01); H01L 29/6653 (2013.01); H01L 29/6656 (2013.01); H01L 29/66545 (2013.01); H01L 29/66795 (2013.01); H01L 29/785 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a fin projecting upwardly from a substrate;
a gate stack engaging the fin;
a source/drain (S/D) feature over the fin;
a gate spacer on a sidewall of the gate stack, the gate spacer having a first sidewall in contact with the gate stack and a second sidewall opposing the first sidewall and directly above the S/D feature; and
a dielectric layer on the sidewall of the gate stack and in contact with the gate stack, the dielectric layer being vertically between the fin and the gate spacer,
wherein a largest thickness of the dielectric layer measured laterally is smaller than a thickness of the gate spacer measured laterally between the first and second sidewalls.