Production of a trench in a semiconductor substrate comprises arranging a mask on the substrate having a window, electrochemically etching the surface exposed by the window, forming a porous substrate and removing the porous substrate

摘要

Production of a trench (5) in a semiconductor substrate (1) comprises: (i) arranging a mask (2) on the substrate having a window (3) in which a substrate surface (4) is exposed; (ii) electrochemically etching the substrate from the substrate surface exposed by the window; (iii) forming a porous substrate (6) in a trench-like region from the substrate surface; and (iv) removing the porous substrate from the trench-like region. Preferred Features: The porous substrate has a thickness of 20-80% of the substrate. The porous substrate is etched using an alkaline etching agent, preferably KOH. The porous substrate is oxidized to form a porous substrate oxide. The substrate contains silicon.