Patent ID: 9653320
Date: 2017-05-16
CPC Classifications: H01L

Claim:
1. A method of patterning a hardmask layer disposed on a metal layer formed on a substrate, comprising: supplying a first etching gas mixture comprising a first carbon-fluorine containing gas and a chlorine containing gas into a processing chamber to etch a portion of the hardmask layer disposed on the metal layer formed on the substrate; subsequently supplying a second etching gas mixture comprising a hydrocarbon gas without the first carbon-fluorine containing gas and the chlorine containing gas from the first etching gas mixture into the processing chamber for a first period of time without applying RF source power or RF bias power to clean the hardmask layer and the substrate disposed in the processing chamber; and subsequently supplying a third etching gas mixture that is different from the first etching gas mixture, the third etching gas mixture comprising a second carbon-fluorine containing gas to continue removing a remaining portion of the hardmask layer until a surface of the metal layer is exposed.