A novel technique for high aspect ratio high resolution patterning of membranes

Abstract

This article presents a new technique for fabrication of high aspect ratio metal patterns on membranes. Two modifications of x-ray lithographic techniques have been employed: simultaneous exposure of a photoresist coated on both sides of the membrane, and membrane exposure from back side using a negative tone photoresist. Both methods provide self-aligned masks for pattern transfer into multiple metal layers. Those techniques have been used for fabrication of high aspect ratio Fresnel zone plates for hard x-ray microscopy. 0.15 μm design rule Fresnel zone plates, with gold structure of 1.6 μm thickness have been fabricated.