Silicon-on-insulator (SOI) wafer fabrication for MEMS applications

In this paper, it is shown that Silicon-On-insulator (SOI) wafers with good surface finish and thickness control can be realized using Silicon Fusion Bonding along with an optimized ethylenediamine-pyrocatechol-water (EDP) etching approach. Single crystal diaphragms of 11 μm thickness have been fabricated using these SOI wafers. These diaphragms were tested and found to withstand N2 gas pressures in excess of 260 psi without rupturing.