Patent ID: 8282845
Filing Date: 2012-10-09
Classification: B81C

Abstract:
1. A method for etching a feature in an etch layer, the method comprising: providing a substrate layer; fabricating a mask feature from a mask layer material, the mask feature being fabricated at a lateral feature position on the substrate layer, the mask feature having a critical lateral extension, wherein fabricating the mask feature comprises fabricating a mask opening in a mask layer on the substrate layer at the lateral feature position and with the critical lateral extension and wherein the mask layer comprises TiW or Al with an aluminum oxide cover layer; depositing an etch layer from an etch layer material on the mask feature and on the substrate layer, the etch layer being deposited to a thickness of more than 2 micrometers from an initial contact face, the etch layer material being selectively etchable relative to the mask layer material, wherein the etch layer comprises Al; and etching a feature in the etch layer at a first lateral position with a lateral extension larger than the critical lateral extension, the etching using an etchant that selectively removes the etch layer material relative to the mask layer material.