Fabrication of micro/nano multifunctional patterns on optical glass through chalcogenide heat-mode resist AgInSbTe

Abstract Heat-mode resists can spatially confine the laser hot spot to achieve subwavelength exposure by laser direct writing. However, due to the lack of systematic research on the dry etching mechanism of them, micro/nano patterning on optical glass materials through heat-mode resists has not been realized with standardized plasma processes. In this paper, the fabrication of sub-wavelength micro/nanostructures on silica substrates through the heat-mode resist is reported. A chalcogenide alloy AgInSbTe (AIST) works as the heat-mode resist. The anti-etching mechanism of the AIST resist in fluorine-based plasma gas was explored with the X-ray photoelectron spectroscopy. High etching selectivity, surface quality, and fidelity are achieved by optimizing the plasma-etching processes. Experimental and theoretical results confirm the effectiveness and feasibility of this technology. A series of micro/nano-pattern structures on silica are prepared, where the minimum feature size is 130 nm, which is about 1/3 the laser wavelength. This work paves an effective and convenient way for the fabrication of subwavelength optical elements on transparent glass substrates.