GeTe photoresist films for both positive and negative heat-mode nanolithography

Binary chalcogenide phase change material GeTe was proposed and investigated as a novel high-resolution inorganic photoresist for laser heat-mode lithography. GeTe possesses both positive and negative photoresist characteristics based on alkaline or acid developing solutions, which can improve the flexibility in fabricating micro/nano devices. Different relief gratings with feature sizes in the range of nanometer to micron were fabricated, and the minimum linewidths can be reduced to 137 nm (positive tone) and 98 nm (negative tone) respectively. The selective wet etching mechanism was discussed with local oxygen concentration mapping of nanopatterns. Moreover, the patterns were successfully transferred onto Si substrate by plasma etching. (C) 2019 Elsevier B.V. All rights reserved.