Patent ID: 9496131
Filing Date: 2016-11-15
CPC Classification: C11D,H01L

Claim Text:
1. A method for cleaning a wafer, the wafer having at its surface an uneven pattern and containing at least one kind element of titanium, tungsten, aluminum, copper, tin, tantalum and ruthenium at surfaces of recessed portions of the uneven pattern, the method comprising: a) a protecting-film-forming step where a liquid chemical for forming a protecting film is retained at least in the recessed portions of the uneven pattern; b) a drying step of removing liquid from the uneven pattern by drying; and c) a film-removing step of removing the protecting film, wherein the liquid chemical for forming a protecting film is a liquid chemical comprising an agent for forming a water-repellent protecting film, and the agent is a compound represented by the general formula [1] wherein R R a represents an integer from 0 to 2; and wherein the agent forms a water-repellent protecting film at least on the surfaces of the recessed portions.