Patent ID: 11915941
Assignee: TOKYO ELECTRON LIMITED
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 14:
15. A method of etching a substrate using a wet atomic layer etching (ALE) process, the method comprising:
receiving the substrate, the substrate having a material exposed, the material comprising a polycrystalline material; and
selectively etching the polycrystalline material by performing multiple cycles of the wet ALE process, wherein each cycle comprises:
a) chemically modifying an exposed surface of the polycrystalline material to provide a modified surface layer, wherein said exposed surface is chemically modified by oxidation of the polycrystalline material using an oxidizing agent;
b) binding a complexing agent to the modified surface layer of the polycrystalline material to provide a complex-bound modified surface layer;
c) rinsing the substrate with a solvent; and
d) selectively removing the complex-bound modified surface layer of the polycrystalline material by exposing the complex-bound modified surface layer to a dissolution solution to dissolve the complex-bound modified surface layer; and
wherein said rinsing the substrate is performed for a time period that increases during said performing the multiple cycles of the wet ALE process.