Design Approaches of MEMS Microphones for Enhanced Performance

Figure 16

Fabrication process of a double-chip microphone design with a single-crystal silicon membrane [169]: (a) a boron etch-stop layer was doped, (b) a BSG layer was deposited and bonding was performed, (c) etching masks were formed, (d) etching of a diaphragm and back plate was performed, and (e) a BSG layer was removed.

(a)

(b)

(c)

(d)

(e)