E-Beam Induced Distortions on SiN X-ray Mask Membrane

摘要

In this work we characterized 1) the resist stress dependence on exposure dose and 2) in-plane distortions of the mask caused by resist and substrate. A NIST standard ring with a SiN membrane window was used throughout this work. Resist stress was determined by measuring the resonant frequency of a membrane coated with resist. Stress was measured at several doses for SAL605, APEX-E and PMMA resists. In-plane distortion was measured using in-situ measurement approach. An array of standard alignment fiducials for Leica - Cambridge EBMF10.5 e-beam system were placed directly on the membrane. Also, an array of fiducials was placed on the NIST ring to provide a reference point for measurements.