Ge2Sb2Te5 Thin Film as a Promising Heat-Mode Resist for High-Resolution Direct Laser Writing Lithography

Ge2Sb2Te5 thin film is investigated as a positive heat-mode resist and environmentally friendly FeCl3 solution is as means an efficient developer. The corrosion selectivity of exposed to as-deposited thin film reaches 2.3 and the etching selectivity of Si to Ge2Sb2Te5 thin film is as high as 15.75. Moreover, high-resolution nanostructures with minimum linewidth of 180 nm and period of 400 nm are obtained along with high resolution of 130 nm. In addition, the mechanism of corrosion selectivity between as-deposited and exposed thin film is further elucidated based on microstructural analysis. Hence, Ge2Sb2Te5 thin film is a promising positive resist for high-resolution direct laser writing lithography.