Nonaqueous organic electrolyte for photoelectrochemical etching of gallium nitride surface.

Graphical abstract GaN surface can be effectively and efficiently etched by organic electrolyte under the prerequisite of UV light and electric field. From the point of electrochemical window, the organic electrolyte has wider electrochemical window than conventional aqueous etchants. Highlights • GaN film can be effectively etched by organic electrolyte. • The dissolution mechanism of organic electrolyte is proposed to etch GaN. • The nonaqueous organic electrolyte is first used for GaN etching. Abstract Nonaqueous organic electrolyte was utilized to etch GaN via photo-electrochemical etching technique. From the point of electrochemical window, the organic electrolyte has wider electrochemical window than conventional aqueous etchants. SEM images show that the pore density is up to 1.2 × 107 per square centimeter. The difference of XPS spectra about survey, Ga 3d and N 1s between the non-etched and freshly etched GaN surface can be explained the formation of Ga(BF 4) 3. The proposed dissolution mechanism can be broadly applied for explaining the etching process of nonaqueous etchants under the assist of electric field and strong light. [ABSTRACT FROM AUTHOR]