Method of making an electrostatic silicon accelerometer

A method for making a solid state accelerometer, comprising:

• depositing a p+ doped layer of epitaxial silicon on a double-sided polished first p- doped silicon wafer;
• dry etching a first pattern on the epitaxial silicon to define flexures and a proof mass;
• fusion bonding a second p- doped silicon wafer to the p+ doped layer of epitaxial silicon;
• thermally oxidizing the exposed surfaces of said first and second p- doped silicon wafers to grow dielectric interlayers to set widths of gaps for the proof mass;
• applying an etch resistant material of a second pattern the dielectric interlayers;
• anisotropically etching the first and second p- doped wafers to make individual flexures and the proof mass;
• removing inner portions of the dielectric interlayers to make the gaps;
• and
• fusion bonding first and second p+ doped silicon stop wafers to the dielectric interlayers of the first and second p- doped silicon wafers, thereby constituting the gaps between the proof mass and the first and second p+doped silicon stop wafers, and sealing the proof mass from volume external to the proof mass.