Patent ID: 7666796

Claim:
A method comprising: providing a material stack on a substrate, wherein the material stack includes a first layer on the substrate, a second layer on the first layer, a third layer on the second layer, a fourth layer on the third layer, and a fifth layer on the fourth layer, and wherein there is etch selectivity between the second layer and the fifth layer, and between the substrate and the third layer, forming a pattern over the fifth layer, wherein the pattern exposes a first region of the material stack and the substrate, and covers a second region of the material stack and the substrate; etching the first region of the fifth layer, the fourth layer, and the third layer, wherein etching the first region of the fifth layer, the fourth layer, and the third layer further comprises removing a first portion of the pattern while leaving a second portion of the pattern in place, and wherein the first portion of the pattern represents a maximum amount that may be removed from the pattern and still allow the pattern to be capable of providing an etch mask; removing the second portion of the pattern; etching the first region of the second layer; etching the second region of the fifth layer and the first region of the first layer; and etching the second region of the fourth layer and a part of the first region of the substrate.