A high rectification efficiency Dual Fin Si0.7Ge0.3/Si/Si0.7Ge0.3 quantum well channel structure FinFET for 2.45 GHz micropower microwave wireless energy harvesting

Abstract In wireless energy harvesting (WEH) systems, the performance of rectifier diodes directly determines the upper limit of rectification efficiency. Schottky diodes and MOSFETs are currently the most widely used rectifier devices, but their performance is unsatisfactory in micro-power density input environments. To address this, this paper proposes and designs a high rectification efficiency Fin Field-Effect Transistors (FinFET) model for 2.45 GHz micro-power microwave WEH using Sentaurus TCAD software simulation. When selecting 16 nm gate length, 6 nm fin width, and 53 nm fin height as the basic structural parameters of the FinFET device, the device’s subthreshold swing approaches the ideal value of 60 mV dec −1 , significantly enhancing the switching speed. Furthermore, a dual-fin structure is adopted to maintain excellent subthreshold swing characteristics and achieve a substantial increase in drive current strength. Finally, a dual-fin strained Si quantum well channel SiGe-OI FinFET structure is proposed to reduce the adverse effects of interfacial scattering on carrier mobility while introducing stress into the channel region to further enhance carrier mobility. The improvement in rectification efficiency is verified by constructing a half-wave rectifier circuit with filter capacitors via the Mixmode module. The rectification efficiencies reach 4.94% and 21.41% when the input power is −20 dBm and −10 dBm, respectively, which are 7 times and 3.4 times higher than conventional near-zero-threshold-voltage Si-based MOS devices under the same conditions.