Patent ID: 9425086
Filing Date: 2016-08-23
CPC Classification: H01L

Claim Text:
1. A method of removing an overhang from an opening of a contact hole formed through a contact film stack of integrated circuit material, comprising: forming a contact film stack on a silicon substrate using a plurality of layers of dielectric material; forming a contact hole in the contact film stack on the silicon substrate; coating a surface of the contact film stack and an interior of the contact hole with liner material; removing the liner material to expose an overhang of at least one of the plurality of layers of dielectric material, wherein removing the liner material to expose the overhang comprises exposing the overhang in an outer layer of the contact film stack by removing the liner material from the outer layer while retaining at least portions of the liner material in one or more inner layers of the contact film stack; selectively removing the retained portions of the liner material from the one or more inner layers of the contact film stack while retaining a portion of the liner material in a bowing profile region of an inner layer of the contact film stack; and removing the overhang.