Micro cantilever probe array with integration of electro-thermal nano tip and piezoresistive sensor

A micro cantilever-lip silicon probe-array with integrated electro-thermal nano-lip and piezoresistive sensor has been presented for NEMS high-density data storage. Such a 1×10 probe-array is designed after the working principle studied. Both analysis and FEM simulation are used for modeling and designing with their results agreeing well, with a tolerance of only 5%. The devices are fabricated by using silicon bulk micromachining technology. The relationship between the resistance of the heater and the temperature of the tip is experimentally obtained and fitted with second order polynomial function. With the fitted results, the pulse-heating property of the devices is characterized. The tested results are in agreement with the simulation. Under pulsed 4V power supply and 3 μs heating period, the tip can be heated to 463.15 K. Near 100 KHz writing rate can be realized, as 6.2 μs is needed for cooling the heating resistor. The sensitivity of piezoresistivity is 5.4×10^-4 under the contact force of 2×10^-7 N, which is sufficient to reading the data pitch on PMMA media.