Straightforward etching of ZnO nanostructures for optical sensor application

Nano etching could be a feasible top down approach to make the rough surface and sharp tips. Among the several etching methods, there are some disadvantages and limitations like, making masks in the case of wet and dry... [ view full abstract ]

Nano etching could be a feasible top down approach to make the rough surface and sharp tips. Among the several etching methods, there are some disadvantages and limitations like, making masks in the case of wet and dry etching, using toxic or corrosive acids in chemical etching, usage of sophisticated and expensive tools like plasma, reactive ion etc., But the nano-etching mechanism proposed here is facile, using non-toxic and non-corrosive photoresist (PR) through a thermo-chemical reaction. The PR consists of carboxylic (COOH) and cyclopentanone (C5H8O) can react with zinc and oxygen atoms respectively on the surface of the ZnO nanostructure. The thermo-chemical reaction is controllable by varying the PR concentration and the reaction time. The optical sensor were fabricated by using the etched ZnO nanorods and the bare ZnO nanorods. Compared with bare ZnO nanorod, the sensing properties of the etched ZnO nanorod sensor were greatly improved.