Patent ID: 7049228
Filing Date: 2006-05-23
Classification: H01L

Abstract:
1. A process for introducing structures into a substrate, wherein the structures contain a set of deep structures and a set of shallow structures, comprising: depositing on the substrate a layer stack comprising at least two layers each containing a different material; depositing a photosensitive layer on the top layer of the layer stack; patterning the photosensitive layer in a lithographic process using a mask containing a set of smaller and a set of larger features, wherein a set of larger openings are used to form the set of deep structures and a set of smaller openings are used to form the shallow structures; developing the photosensitive layer, wherein a set of larger patterned features and a set of smaller patterned features are formed in the photosensitive layer; transferring the pattern in the photosensitive layer into a first layer of the layer stack residing beneath the photosensitive layer, wherein the set of smaller and the set of larger openings are formed; and etching a second layer of the layer stack beneath the first layer, wherein the second layer is completely etched down to a third layer at locations corresponding to the larger openings, and wherein the second layer is only partially etched so that the second layer remains closed at locations corresponding to the smaller openings.