Chalcogenide phase-change thin films used as grayscale photolithography materials

Abstract

Chalcogenide phase-change thin films are used in many fields, such as optical information storage and solid-state memory. In this work, we present another application of chalcogenide phase-change thin films, i.e., as grayscale photolithgraphy materials. The grayscale patterns can be directly inscribed on the chalcogenide phase-change thin films by a single process through direct laser writing method. In grayscale photolithography, the laser pulse can induce the formation of bump structure, and the bump height and size can be precisely controlled by changing laser energy. Bumps with different height and size present different optical reflection and transmission spectra, leading to the different gray levels. For example, the continuous-tone grayscale images of lifelike bird and cat are successfully inscribed onto Sb(2)Te(3) chalcogenide phase-change thin films using a home-built laser direct writer, where the expression and appearance of the lifelike bird and cat are fully presented. This work provides a way to fabricate complicated grayscale patterns using laser-induced bump structures onto chalcogenide phase-change thin films, different from current techniques such as photolithography, electron beam lithography, and focused ion beam lithography. The ability to form grayscale patterns of chalcogenide phase-change thin films reveals many potential applications in high-resolution optical images for micro/nano image storage, microartworks, and grayscale photomasks.

Non-binary Colour Modulation for Display Device Based on Phase Change Materials

“…Sputtered Sb 2 Te 3 and GeTe films are amorphous1314. The crystallization temperature (Tc) of Sb 2 Te 3 is much lower than that of GeTe151617; thus, when a external stimulus (i.e., heat, laser or current) is applied, the priority of Sb 2 Te 3 crystallization is guaranteed when the temperature reaches the Tc of Sb 2 Te 3 but is lower than that for GeTe1819. Owing to the big Tc difference between Sb 2 Te 3 and GeTe, it is easier and more stable to realize multistate phase combinations and continuous colour modulation (see below) and also improve the optical or electrical operation window compared with the device based on two ultrathin GST films with different thicknesses.…”

Rapid Surface Oxidation of Sb2Te3 as Indication for a Universal Trend in the Chemical Reactivity of Tetradymite Topological Insulators

“…However, for surface device applications, detailed knowledge of the stability limits of the surface properties and the behavior of the TSS under ambient conditions are required, especially as preparation techniques of TIs are being extended towards ultrathin freestanding layers 18 , nanocrystals 19 , nanowires and nanotubes 20 , step edges 21 or patterning by lithography 22 . In a context that is much closer to applications and despite of multiple attempts to estimate the reactivity of the prototypical TIs [23][24][25][26] , many open issues remain.…”

Realization of III–V Semiconductor Periodic Nanostructures by Laser Direct Writing Technique

“…With the irradiation of a focused laser beam, the local area of the film was quickly heated up to a high temperature and then rapidly cooled down to room temperature when the laser beam moved away. This process resulted in obvious structural transformation depending on the variation of volume and the surface height of photoresists [26]. …”