Three=dimensionally structuring single crystal substrate

摘要

Producing 3-D structures in a substrate of single crystal material with a diamond structure comprises forming one or more recesses (or even openings) by applying an etching mask with an opening which has an area slightly smaller than that of the recess to be formed and through which the substrate surface is anisotropically etched. Most of the etching operation involves etching subsidiary recesses which separate opposite recess side faces into non-contacting separate subsidiary side faces (i.e. the side faces of the subsidiary recesses), these subsidiary side faces merging, before or when the desired etched depth is reached, to form respective undivided side faces and to unite the subsidiary recesses into the recess. The mask has at least two openings (5) separated by a web (10) extending between opposite sides of the desired etching area and having a width (b) which is completely under-etched on reaching the desired etching area. Each mask opening (5) lies with each pair of its opposite corners on each edge (8) of the desired etching area (9).