An improved technique for resist‐profile control in holographic lithography

Undercut profiles are achieved in holographically exposed resist when the maximum of the orthogonal standing wave is placed at the resist–substrate interface. We demonstrate that this condition can be achieved by tilting the substrate normal out of the plane of the interferometer. The condition of maximum interface intensity is detected by determining when there is maximum optical coupling into a test film of 10 nm‐thick photoresist. Exposure of the test film is detected by diffraction.