Thursday, April 17, 2008

US Patent 7358822 - MEMS oscillator using temperature modulation control

One common method to actuate MEMS cantilevers and other structures is to include a thermal heater as part of the MEMS structure and use a bi-layer of material having differing thermal expansion coefficients which causes bending upon heating. However, for applications in MEMS oscillators a proximal heater can have adverse effects on the resonance frequency. This patent from Cornell teaches using a remote laser for the actuation to avoid such problems. Claim 1 reads:

1. A method comprising:

modulating temperature of a portion of a device having a microelectromechanical oscillator formed from a device layer supported by a support layer; and

wherein temperature modulation creates oscillation of the oscillator; and

wherein the oscillator is spaced apart from the portion of the device having its temperature modulated.