US 12,354,880 B2
High aspect ratio etch with infinite selectivity
Leonid Belau, Pleasanton, CA (US); and Eric A. Hudson, Berkeley, CA (US)
Assigned to Lam Research Corporation, Fremont, CA (US)
Appl. No. 17/904,046
Filed by Lam Research Corporation, Fremont, CA (US)
PCT Filed Jan. 29, 2021, PCT No. PCT/US2021/015650
§ 371(c)(1), (2) Date Aug. 11, 2022,
PCT Pub. No. WO2021/162871, PCT Pub. Date Aug. 19, 2021.
Claims priority of provisional application 62/975,899, filed on Feb. 13, 2020.
Prior Publication US 2023/0081817 A1, Mar. 16, 2023
Int. Cl. H01L 21/311 (2006.01); H01J 37/32 (2006.01); H01L 21/67 (2006.01)
CPC H01L 21/31116 (2013.01) [H01J 37/32091 (2013.01); H01J 37/32146 (2013.01); H01J 37/32477 (2013.01); H01J 37/32724 (2013.01); H01J 37/32816 (2013.01); H01L 21/31144 (2013.01); H01L 21/67069 (2013.01); H01J 2237/182 (2013.01); H01J 2237/2001 (2013.01); H01J 2237/3327 (2013.01); H01J 2237/3346 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for processing a substrate, the substrate comprising underlying material and a mask, wherein the underlying material comprises at least one layer of silicon oxide, and wherein the mask is positioned above the underlying material and is patterned to define locations where features will be etched in the underlying material, the method comprising:
a. generating a plasma in a reaction chamber; and
b. exposing the substrate to the plasma in the reaction chamber to simultaneously
(i) etch the features in the underlying material, and
(ii) deposit an upper mask protector layer on the mask, wherein the upper mask protector layer forms on top of the mask in a selective vertically-oriented directional deposition,
wherein the upper mask protector layer comprises a CxBryFz-based material, a CxClyFz-based material, a CxIyFz-based material, or a combination thereof.