US 12,308,250 B2
Pre-etch treatment for metal etch
Scott Lefevre, Albany, NY (US); and Angelique Raley, Albany, NY (US)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on May 12, 2022, as Appl. No. 17/742,445.
Prior Publication US 2023/0369064 A1, Nov. 16, 2023
Int. Cl. H01L 21/3213 (2006.01); H01J 37/32 (2006.01); H01L 21/02 (2006.01)
CPC H01L 21/32136 (2013.01) [H01J 37/32449 (2013.01); H01L 21/0234 (2013.01); H01J 2237/332 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of processing a substrate, the method comprising:
exposing a substrate to a first plasma generated from a pretreatment gas comprising carbon, the substrate comprising a first layer comprising a dielectric material and a second layer comprising a metal, the first plasma being exposed to the first layer and the second layer, the first plasma forming a first carbonaceous deposit over the first layer and a second carbonaceous deposit over the second layer, the first carbonaceous deposit having a different composition than the second carbonaceous deposit;
exposing the first carbonaceous deposit and the second carbonaceous deposit to a second plasma generated from an etch gas comprising halogen, the second plasma selectively etching the second carbonaceous deposit relative to the first carbonaceous deposit to expose a surface of the second layer; and
exposing the first carbonaceous deposit and the exposed surface of the second layer to the second plasma to selectively etch the second layer relative to the first carbonaceous deposit, the first carbonaceous deposit protecting the first layer from being etched by the second plasma.