Handbook of Silicon Based MEMS Materials and Technologies

24.7. Examples of Wet Etching

This section presents typical examples of anisotropic etching, showing how it can be used alone and in combination with other processing techniques. A rather unusual example combining many micromachining processes is considered in more detail due to its pedagogical value. A thorough review of the hundreds of different structures that can be micromachined by involving wet etching is out of the scope of the present book.

24.7.1. Single Mask, Single Etch

As shown in Figure 24.1, anisotropic etching can be used to produce deep vertical grooves, square diaphragms, V-grooves, and U-grooves on {110} and {100} silicon wafers by the use of a single mask and a single etch. For Si{100}, Figure 24.1b describes the crystallographic ...