US 12,315,739 B2
Isotropic silicon nitride removal
Mikhail Korolik, San Jose, CA (US); Paul E. Gee, San Jose, CA (US); Wei Ying Doreen Yong, Singapore (SG); Tuck Foong Koh, Singapore (SG); John Sudijono, Singapore (SG); Philip A. Kraus, San Jose, CA (US); and Thai Cheng Chua, Cupertino, CA (US)
Assigned to Applied Materials, Inc., Santa Clara, CA (US)
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Oct. 11, 2022, as Appl. No. 17/963,687.
Prior Publication US 2024/0120210 A1, Apr. 11, 2024
Int. Cl. H01L 21/3213 (2006.01); H01L 21/02 (2006.01); H01L 21/3065 (2006.01)
CPC H01L 21/32136 (2013.01) [H01L 21/02219 (2013.01); H01L 21/02274 (2013.01); H01L 21/3065 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of etching a silicon-containing material, the method comprising:
flowing a first fluorine-containing precursor and an additive precursor into a remote plasma region of a semiconductor processing chamber, wherein the additive precursor comprises a halogen other than fluorine;
flowing a sulfur-containing precursor into the remote plasma region of the semiconductor processing chamber;
forming a plasma within the remote plasma region to generate plasma effluents of the first fluorine-containing precursor and the sulfur-containing precursor;
flowing the plasma effluents into a processing region of the semiconductor processing chamber, wherein a substrate is positioned within the processing region, and wherein the substrate comprises a trench formed through stacked layers including alternating layers of silicon nitride and silicon oxide; and
isotropically etching the layers of silicon nitride while substantially maintaining the silicon oxide.