Ge-Sb Thin Films Patterned by Heat-Mode Lithography

A binary Te-free phase-change material Ge9.15Sb90.85 (GS) is investigated as the heat-mode resist. A high etching selectivity ratio can be achieved by matching a suitable developer. A reasonable explanation for the positive development is proposed based on the chemical binding energy analysis. High-resolution relief patterns are fabricated on the GS films by laser direct writing and wet etching. It reveals that GS is a promising heat-mode resist for the fabrication of photonic devices.