Patent ID: 8715909

Claim:
A method of forming a semiconductor device, the method comprising: forming an integrated circuit by forming a pattern comprising a first feature and a neighboring second feature on a semiconductor body, the integrated circuit being formed by simultaneously exposing a first mask and a second mask, wherein the first and the second features are formed at the same time during the simultaneous exposure, wherein a distance between the first and the second features is near a resolution limit of a optical system performing the exposing, wherein the first mask comprises transparent regions bounded by opaque regions, wherein the second mask comprises transparent regions bounded by phase shift regions, wherein boundaries of the pattern are formed by a superposition of a first light exposed by the transparent regions of the first mask with a second light exposed by the phase shift regions of the second mask, wherein center portions of the pattern are formed by a superposition of the first light exposed by the transparent regions of the first mask with a third light exposed by the transparent regions of the second mask, and wherein the second light is configured to destructively interfere with the first light.