Fabry-Perot-type antireflective coating for deep-ultraviolet binary photomask applications
Journal
Applied Optics
Journal Volume
41
Journal Issue
19
Pages
3961-3965
Date Issued
2002
Author(s)
Abstract
We demonstrate an antireflective coating structure, which is based on the three-layer metal interference called the Fabry-Perot structure, for a deep-ultraviolet binary mask. The antireflective coating structure is composed of a metal-oxide-metal stack. By addition of different optimized structures, reflectances of less than 1.5% at both 248 and 193 nm have been achieved. At the three-layer Fabry-Perot structure, the bottom chrome layer provides suitable absorption. By controlling the thickness of the intermediate silicon oxide layer, we can tune the minimum-reflection regime to the desired exposure wavelength. The top metal layer can prevent charge accumulation during e-beam writing.
Type
journal article