US 11,670,516 B2
Metal-containing passivation for high aspect ratio etch
Karthik S. Colinjivadi, San Jose, CA (US); Samantha SiamHwa Tan, Fremont, CA (US); Shih-Ked Lee, Fremont, CA (US); George Matamis, Danville, CA (US); Yongsik Yu, Milpitas, CA (US); Yang Pan, Los Altos, CA (US); Patrick Van Cleemput, San Jose, CA (US); Akhil Singhal, Beaverton, OR (US); Juwen Gao, San Jose, CA (US); and Raashina Humayun, Los Altos, CA (US)
Assigned to Lam Research Corporation, Fremont, CA (US)
Appl. No. 17/259,526
Filed by Lam Research Corporation, Fremont, CA (US)
PCT Filed Aug. 19, 2019, PCT No. PCT/US2019/047095
§ 371(c)(1), (2) Date Jan. 11, 2021,
PCT Pub. No. WO2020/041213, PCT Pub. Date Feb. 27, 2020.
Claims priority of provisional application 62/722,337, filed on Aug. 24, 2018.
Prior Publication US 2021/0242032 A1, Aug. 5, 2021
Int. Cl. H01L 21/311 (2006.01); H01L 21/02 (2006.01)
CPC H01L 21/31116 (2013.01) [H01L 21/02063 (2013.01); H01L 21/31144 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of forming an etched feature in a dielectric-containing stack on a substrate, the method comprising:
(a) partially etching the feature in the dielectric-containing stack by exposing the substrate to a first plasma comprising an etching reactant;
(b) after (a), depositing a protective film on sidewalls of the feature, the protective film comprising at least one of a tungsten carbonitride, a tungsten sulfide, tin, a tin-containing compound, molybdenum, a molybdenum-containing compound, a ruthenium sulfide, an aluminum sulfide, zirconium, and a zirconium-containing compound, wherein the protective film is not deposited on bottoms of the etch features; and
(c) repeating (a)-(b) until the feature is etched to a final depth, wherein the protective film deposited in (b) substantially prevents lateral etch of the feature during (a), and wherein the feature has an aspect ratio of about 5 or greater at its final depth.