Study on convex-corner undercutting formed by masked-maskless etching in aqueous KOH

Masked-maskless etching is a novel bulk micromachining technology for compl ex silicon microstructures. Thr convex-corner undercutting of masked-maskle ss etching is far different from that of normal masked etching. An experime ntal investigation has been conducted to discover the configuration and top ological evolution of the convex-corner undercutting under masked-maskless etching. Based on the experimental results, the compensation criteria for t he masked-maskless formed convex-corner undercutting are obtained and the c orresponding compensation schemes are provided.