US 11,658,043 B2
Selective anisotropic metal etch
Jonathan Shaw, Oakland, CA (US); Priyadarshi Panda, Jersey City, NJ (US); Nancy Fung, Livermore, CA (US); Yongchang Dong, Sunnyvale, CA (US); Somaye Rasouli, San Jose, CA (US); and Gene Lee, San Jose, CA (US)
Assigned to APPLIED MATERIALS, INC., Santa Clara, CA (US)
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Jul. 29, 2021, as Appl. No. 17/389,119.
Claims priority of provisional application 63/074,176, filed on Sep. 3, 2020.
Prior Publication US 2022/0068661 A1, Mar. 3, 2022
Int. Cl. H01L 21/3213 (2006.01)
CPC H01L 21/32136 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method of patterning a substrate, comprising:
exposing an initial surface of a metal-containing layer to an ion doping implantation by a plasma doping (PLAD) technique to produce a surface of the metal-containing layer during a pre-amorphization treatment process; then
modifying the surface of the metal-containing layer formed over a substrate positioned in a processing region of a processing chamber by exposing the surface of the metal-containing layer to a chlorine-containing gas precursor and an oxygen-containing gas precursor to form a modified surface of the metal-containing layer;
directing plasma effluents of an inert gas precursor towards the modified surface of the metal-containing layer, wherein the plasma effluents of the inert gas precursor are directed by applying a bias voltage to a substrate support holding the substrate;
anisotropically etching the modified surface of the metal-containing layer with the plasma effluents of the inert gas precursor to form a first recess having a first sidewall in the metal-containing layer, wherein the plasma effluents of the inert gas precursor selectively etch the modified surface of the metal-containing layer relative to unmodified portions; and
exposing the first recess to an etchant gas mixture including a passivation gas and an etchant gas to remove additional metal from the metal-containing layer.