Electrostrictive Tunable Capacitors and High-Performance 2D Crystal Transistors for Energy-Efficient Applications

Tunable capacitors based on electrostriction in piezoelectric barriers are presented. Electrostriction leads to a modulation of the piezoelectric barrier layer thickness caused by electrostatic attractive forces between the plates of a capacitor under applied voltage. Using this mechanism, a high range of capacitance values with a high capacitance tuning ratio, and wide tunability are obtained. Furthermore, using this electrostrictive piezoelectric capacitor in the gate stack of a two-dimensional (2D) crystal transistor, such as MoS2 transistor, a higher gate capacitance and an ON-current boost are obtained. This allows the transistor switch to operate at a smaller bias voltage in energy-efficient applications.