Method and structure of monolithically integrated ic-mems oscillator using ic foundry-compatible processes

A method of forming a monolithic MEMS and integrated circuit device, the method comprising:

• providing a first semiconductor substrate having a first surface region;
• forming one or more CMOS integrated circuit device provided on a CMOS integrated circuit device region overlying the first surface region, the CMOS integrated circuit device region having a CMOS surface region;
• forming a dielectric layer overlying the CMOS surface region;
• joining a second semiconductor substrate having a second surface region to the CMOS surface region by bonding the second surface region to the dielectric layer, the second semiconductor substrate comprising a bulk substrate, an overlying insulating layer, and a single crystal device layer, the single crystal device layer comprising the second surface region;
• thinning the second semiconductor substrate to a desired thickness including the single crystal device layer, the insulating layer, and a portion of the bulk substrate while maintaining attachment to the dielectric layer;
• and
• forming one or more MEMS structures within one or more portions of the desired thickness of the second semiconductor substrate, the one or more MEMS structures being configured to be supported by one or more members integrally formed on the desired thickness of the second semiconductor substrate to cause the one or more MEMS structures to move in an oscillating manner characterized by a frequency range.