High rectification efficiency Gate-All-Around Nanosheet and Nanowire nFETs for 2.45 GHz weak energy density microwave wireless power transmission

Abstract

The 2.45 GHz microwave signals in the environment can be collected by the microwave wireless power transmission system for applications. However, microwave signals in the 2.45 GHz band are in the weak energy density region, and receiver circuits with ordinary Si-based MOSFET as the rectifier device have low rectification efficiency. Therefore, based on Sentaurus TCAD simulation software, this paper designs and optimizes low-threshold-voltage Gate-All-Around (GAA) Nanosheet nFET and Gate-All-Around (GAA) Nanowire nFET models, taking advantage of the common-gate-stacking of GAA devices to achieve high drive current, low reverse leakage current, and low subthreshold swing. Finally, a half-wave rectifier circuit with a 0.1 pF filter capacitor and a 20 kΩ load resistor is constructed using the mixed-mode module of Sentaurus TCAD to validate the rectification performance of the two devices. At an input energy density of −10 dBm, the GAA Nanowire nFET achieves a rectification efficiency of 19.745 %, followed by the GAA Nanosheet nFET at 18.092 % and the Si-based nMOSFET at 10.942 %. At an input energy density of −15 dBm, the rectification efficiency drops to 9.806 %, 8.514 %, and 5.041 % for the GAA Nanowire nFET, the GAA Nanosheet nFET, and Si-based nMOSFET, respectively. These results confirm the superiority of GAA architectures in 2.45 GHz weak energy density microwave rectification, with the Nanowire variant consistently outperforming the Nanosheet counterpart by a small margin.