Structure and optical properties of amorphous AsS3-WS3 3-WS 3 thin films prepared by spin-coating using mixed n-propylamine-based solutions of AsS3 3 glass and (NH4)2WS4 4 ) 2 WS 4 powder

Abstract

Engineering new chalcogenide solids improves the desired functionality of the materials and may open the way for new applications. Here we discuss the preparation of As x S 100-x amorphous thin films modified with WS3 3 by the sol-gel method. We show that the formation of homogeneous, transparent, and stable n-propylaminebased solutions by mixing 0.02M As x S 100-x and 0.02M (NH4)2WS4 4 ) 2 WS 4 solutions is feasible for the As content in the chalcogenide glass precursor x <= 25 at.%. Above this limit, rapid and massive precipitation occurs in the solutions. We further demonstrate the preparation of amorphous thin films along the pseudo-binary AsS3- 3- WS3 3 tie-line and provide information about the role of WS3 3 on optical properties and the structure of tungsten- based chalcogenide thin films. Due to a significant etching contrast between annealed AsS3-WS3 3 -WS 3 thin films at 70 and 240 degrees C, we propose tungsten-based chalcogenide thin films as a suitable platform for application in wet-lithography.