Patent ID: 9136303
Filing Date: 2015-09-15
Classification: H01L

Abstract:
1. A method of protecting a CMOS device during the formation of a photonic device within an integrated photonic semiconductor structure, the method comprising: depositing a conformal layer of germanium over the CMOS device and over an adjacent area to the CMOS device; depositing a conformal layer of dielectric hardmask over the layer of germanium; depositing a layer of photoresist over the conformal layer of dielectric hardmask; applying a first mask level to the layer of photoresist for patterning the layer of photoresist, the patterning of the layer of photoresist forming a first patterned layer of photoresist over the conformal layer of dielectric hardmask, the first patterned layer of photoresist including photoresist for both covering the CMOS device and covering a photonic device formation region within the adjacent area, the first patterned layer of photoresist including opening regions exposing regions of the conformal layer of dielectric hardmask; etching openings into the exposed regions of the conformal layer of dielectric hardmask, the exposed regions being adjacent to the photonic device formation region; removing the first patterned layer of photoresist; and etching germanium material from the conformal layer of germanium at a location corresponding to the exposed regions of the conformal layer of dielectric hardmask, remaining germanium material underlying the photoresist covering the photonic device formation region for creating the photonic device; wherein the conformal layer of germanium deposited over the CMOS device protects the CMOS device.