Selective wet-etching and characterization of chalcogenide thin films in inorganic alkaline solutions

This paper deals with sensitivity of chalcogenide based photoresists in inorganic alkaline solutions. The thin films of As 33 S 67 , As 33 S 50 Se 17 , As 33 S 33.5 Se 33.5 , As 33 S 17 Se 50 , and As 33 Se 67 were studied. The selective wet-etching was carried out using NaOH, Na 2 S and (NH 4 ) 2 S alkaline solutions. The different sensitivity according to sample composition and used etching solution were found. Chalcogenide films as a potential photoresists could be classified either as 'high-contrast' or 'low-contrast' depending on the sample compositions, type of etchant and its concentration or on incident light energy.