US 12,471,344 B2
Dry etching of semiconductor structures with fluorine-containing gases
Tze-Chung Lin, Hsinchu (TW); Han-Yu Lin, Nantou County (TW); Fang-Wei Lee, Hsinchu (TW); Li-Te Lin, Hsinchu (TW); and Pinyen Lin, Rochester, NY (US)
Assigned to Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on Aug. 30, 2021, as Appl. No. 17/461,186.
Prior Publication US 2023/0064393 A1, Mar. 2, 2023
Int. Cl. H10D 64/01 (2025.01); H01L 21/3065 (2006.01); H10D 30/01 (2025.01); H10D 30/67 (2025.01); H10D 62/10 (2025.01)
CPC H10D 64/017 (2025.01) [H01L 21/3065 (2013.01); H10D 30/031 (2025.01); H10D 30/6757 (2025.01); H10D 62/116 (2025.01); H10D 64/018 (2025.01); H10D 30/6735 (2025.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
forming a fin structure with a stacked fin portion on a substrate, wherein the stacked fin portion comprises a first semiconductor layer and a second semiconductor layer, and wherein the second semiconductor layer comprises germanium;
forming a protective layer on top and sidewall surfaces of the fin structure;
etching the protective layer and the fin structure to form a first opening; and
etching, through the first opening, a portion of the second semiconductor layer with a fluorine-containing gas to form a second opening, wherein the second opening is surrounded by the protective layer, the first semiconductor layer, and the second semiconductor layer.