Patent ID: 11866831
Assignee: TOKYO ELECTRON LIMITED
Field: Surface technology, coating (Chemistry)
Classification: CPC C  H | IPC C  H

Claim 13:
14. A method of etching copper using a wet atomic layer etching (ALE) process, the method comprising:
a) receiving a substrate having a copper (Cu) metal layer with an oxidized Cu surface layer formed thereon;
b) exposing the oxidized Cu surface layer to a complexation solution comprising a complexing agent to bind the complexing agent to the oxidized Cu surface layer and form a complex-bound oxidized Cu surface layer on the Cu metal layer;
c) rinsing the substrate with a first purge solution to remove the complexation solution from a surface of the substrate;
d) selectively removing the complex-bound oxidized Cu surface layer from the Cu metal layer by exposing the complex-bound oxidized Cu surface layer to a dissolution solution that dissolves the complex-bound oxidized Cu surface layer and forms a new oxidized Cu surface layer on the Cu metal layer; and
e) rinsing the substrate with a second purge solution to remove the dissolution solution from the surface of the substrate and etch the Cu metal layer.