Ultra-high density MEMS probe memory device

We have demonstrated a MEMS memory device utilizing an array of cantilevered AFM probe tips fabricated directly on standard CMOS, and integrated with a ferroelectric media on a movable platform by wafer bonding. The MEMS process uses low-temperature poly-SiGe to fabricate cantilevers with sub-100nm tips and suspended metallization to connect the tips to read-write circuitry in the CMOS. The probe tip array interfaces with a single-crystal PZT media film upon which data densities on the order of Tb/in^2 have been demonstrated. The mover is actuated electromagnetically with>100 micron stroke and sub-nm position sensing. The cantilever, mover and cap wafers are integrated using AuSn solder-based wafer bonding.