Patent ID: 6867143

Claim:
A method for etching a semiconductor substrate mask the semiconductor substrate having at least one dielectric layer over a major surface thereof, the method comprising the steps of: a) depositing a layer of metallic germanium over the at least one dielectric layer; b) patterning the layer of metallic germanium to form a germanium hard mask, as a top most layer over the at least one dielectric layer, the patterning step comprising: i) depositing a photo resist layer over the layer of metallic germanium; ii) exposing the photo resist layer to light and developing the exposed photo resist layer to form a photolithography image; iii) etching the layer of metallic germanium through the photolithography image; and iv) removing the photolithography image prior to selectively etching the at least one dielectric layer through the germanium hard mask; c) selectively etching the at least one dielectric layer through the germanium hard mask with the germanium hard mask as a top most layer to form an opening in the at least one dielectric layer; d) selectively etching the semiconductor substrate through the opening in the at least one dielectric layer; and e) removing the layer of metallic germanium after performing the step of selectively etching the at least one dielectric layer and before performing the step of selectively etching the semiconductor substrate.