US 11,658,042 B2
Methods for etching structures and smoothing sidewalls
Nancy Fung, Livermore, CA (US); and Gabriela Alva, Santa Clara, CA (US)
Assigned to Applied Materials, Inc., Santa Clara, CA (US)
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Jul. 7, 2021, as Appl. No. 17/369,812.
Claims priority of provisional application 63/067,117, filed on Aug. 18, 2020.
Prior Publication US 2022/0059365 A1, Feb. 24, 2022
Int. Cl. H01L 21/3213 (2006.01); C23F 1/12 (2006.01); H01L 21/311 (2006.01); H01L 21/306 (2006.01); H01L 21/3065 (2006.01)
CPC H01L 21/32135 (2013.01) [C23F 1/12 (2013.01); H01L 21/3065 (2013.01); H01L 21/30625 (2013.01); H01L 21/31116 (2013.01); H01L 21/32136 (2013.01); H01L 21/32139 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method for patterning a material layer on a substrate, comprising:
forming a hard mask layer on a material layer disposed on a substrate, the material layer comprising a plurality of first layers and a plurality of second layers alternately formed over the substrate;
performing a first etch process to form features in the material layer through the hard mask layer by supplying a first etching gas; and
performing a second etch process to smooth sidewalls of the features formed in the material layer by suppling a second etching gas, wherein
the first etching gas is supplied continuously and the second etching gas is pulsed.