Material removal process for self-aligned contacts
View Patent ↗A method is disclosed of removing a first material disposed over a second material adjacent to a field effect transistor gate having a gate sidewall layer that comprises an etch-resistant material on a gate sidewall. The method includes subjecting the first material to a gas cluster ion beam etch process to remove first material adjacent to the gate, and detecting exposure of the second material during the gas cluster ion beam (GCIB) etch process.
1. A method for fabricating a semiconductor device, the method comprising:
subjecting a first material to a gas cluster ion beam etch process to remove the first material, the first material disposed over a second material and adjacent to a field effect transistor gate comprising a gate sidewall layer that comprises an etch-resistant material on a gate sidewall; and
detecting exposure of the second material during the gas cluster ion beam etch process, wherein detecting exposure of the second material comprises sensing removal of the second material by the gas cluster ion beam etch process, wherein detecting exposure of the second material comprises sensing removal of the second material by spectroscopy.