US 12,495,568 B2
Dummy Fin structures and methods of forming same
Wan-Yi Kao, Baoshan Township (TW); Hung Cheng Lin, Hsinchu (TW); Che-Hao Chang, Hsinchu (TW); Yung-Cheng Lu, Hsinchu (TW); and Chi On Chui, Hsinchu (TW)
Assigned to Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Feb. 21, 2022, as Appl. No. 17/676,470.
Prior Publication US 2023/0268426 A1, Aug. 24, 2023
Int. Cl. H10D 30/01 (2025.01); H01L 21/02 (2006.01); H10D 30/62 (2025.01)
CPC H10D 30/0243 (2025.01) [H01L 21/02164 (2013.01); H01L 21/02167 (2013.01); H10D 30/6211 (2025.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor device comprising:
a first fin structure and a second fin structure protruding from a substrate;
a first epitaxial source/drain region in the first fin structure;
a second epitaxial source/drain region in the second fin structure;
a shallow trench isolation (STI) region between the first fin structure and the second fin structure;
a dummy fin disposed between the first epitaxial source/drain region and the second epitaxial source/drain region, wherein the dummy fin comprises a first dielectric material and a second dielectric material, the first dielectric material and the second dielectric material having carbon concentrations that are in a range from 15 percent to 25 percent by weight of carbon, wherein the first dielectric material has a greater percentage atomic carbon concentration than a percentage atomic carbon concentration of the second dielectric material; and
a dielectric liner disposed on sidewalls and a top surface of the STI region, wherein the dielectric liner is also disposed between the STI region and the dummy fin, wherein a third dielectric material of the STI region is different from a fourth dielectric material of the dielectric liner, wherein topmost surfaces of the dielectric liner are disposed below a top surface of the first dielectric material, a top surface of the second dielectric material, and a topmost surface of the first fin structure.