Positive and negative properties of laser heat-mode resists

The GeSbTe (GST) thin films are usually used as optical and electronic data recording materials. In this work, the GST thin films were used as both negative and positive resists, and the positive and negative tone pattern structures were fabricated on the GST thin films, accordingly. The GST films were first deposited on the substrate, then the laser exposures were conducted through a focused laser beam spot. For negative resist, a Tetramethyl ammonium hydroxide (TMAH) was used as developing solution. For positive resist, (NH4)2S was used as developing solution. The structure heights of positive and negative resists are 53 nm and 180 nm were obtained, respectively. This work provides an effective method for fabricating the micro/nanostructures of optical and electronic elements.