RF characterization of unipolar nanorectifiers at zero bias

Abstract

A novel unipolar nanodevice, the self-switching diode (SSD), has recently shown promising properties as an ultrahigh-speed detector by exploiting its nonlinear diode-like behavior and its inherently low parasitic capacitance. In this report, two large SSD arrays, each has ∼1000 SSDs connected in parallel within the fingers of an inter-digital structure, were characterized based on coplanar measurement in the microwave region using a network analyzer. These SSD arrays were realized in a single lithography step, hence allowing for a simple, fast and low-cost fabrication process. Analysis on rectification properties of SSD is presented and compared with the measurement results. Despite of the large impedance mismatch between SSD array and measurement system, the device was able to rectify microwave signal with extrinsic responsivity achieved up to 400 V/W at unbiased condition. The estimated noise-equivalent power was ∼41 pW/Hz1/2, comparable to other diode-based rectifiers at high speed.