SelectiveSensitivity of contact MEMS position sensors with sidewall piezoresistors

Some results in characterization of two contact MEMS position sensors with sidewall piezoresistors are presented. Devices with in-plane travel range of about 50pm comprise of one and the same symmetrical transducer with two Π-shaped flexures. For first time, just by means of different configuration of the same sidewall piezoresistors in the same flexures, position sensors which are selectively sensitive in X or Y direction were prototyped and tested. Experimentally measured ratio of the displacement sensitivities in Y vs. X direction of the first type sensor was 16.5 and same ratio of the sensitivities in X vs. Y direction of the second type was 27.6.