Integrated Nano Mechanical Atomic Clock

The radio spectrum is a dwindling natural resource. By some estimates in less than a decade there will be no more frequencies left for the next-generation of palmtop computers and handheld communicators. But outfitting every wireless device - from a nextgeneration palmtop computer to a basic FM radio - with a nano-mechanical clock that's accurate down to ten quadrillionths of a second per day could reopen the radio spectrum for tomorrow's new business. This will be accomplished by using atomic clocks to implement time-division multiplexing: allowing many devices to share the same frequency, but just at different non-overlapping times. In principle, an atomic clock could multiplex different transmitters every 250 nanoseconds. Atomic clocks that regulate data flow for the Internet are shoe-box sized devices that consume 150 watts of power and cost $2000. The goal of this project is to shrink the package down to one-centimeter cubed, reduce the power consumed down to 50 milliwatts, and cut the cost to possibly $100.
We report on one recent research result, the fabrication and characterization of low power high- Q piezoelectric resonators. The sputter deposition of c-axially oriented Auminum Nitride (AlN) piezoelectric films (~ 1 �m thick) on to silicon <100> substrates was achieved using a Novellus m2i DC magnetron sputtering tool. AlN films exhibit good columnar structure and low residual stress (20 MPa).