Zero Bias Power Detector Circuits based on MoS$_2$ Field Effect Transistors on Wafer-Scale Flexible Substrates

TL;DR

This paper presents the development of wafer-scale, flexible, zero-bias power detectors using MoS$_2$ FETs, demonstrating high responsivity and dynamic range at Ku-band frequencies, outperforming existing technologies.

Contribution

It introduces a novel wafer-scale fabrication process for flexible MoS$_2$ FET-based power detectors with record performance metrics.

Findings

Operates in Ku-band (12-18 GHz) with high responsivity

Achieves over 30 dB dynamic range, outperforming CMOS and GaAs diodes

Demonstrates flexible, wafer-scale fabrication of power detectors

Abstract

We demonstrate the design, fabrication, and characterization of wafer-scale, zero-bias power detectors based on two-dimensional MoS$_2$ field effect transistors (FETs). The MoS$_2$ FETs are fabricated using a wafer-scale process on 8 $\mu$m thick polyimide film, which in principle serves as flexible substrate. The performances of two CVD-MoS$_2$ sheets, grown with different processes and showing different thicknesses, are analyzed and compared from the single device fabrication and characterization steps to the circuit level. The power detector prototypes exploit the nonlinearity of the transistors above the cut-off frequency of the devices. The proposed detectors are designed employing a transistor model based on measurement results. The fabricated circuits operate in Ku-band between 12 and 18 GHz, with a demonstrated voltage responsivity of 45 V/W at 18 GHz in the case of monolayer MoS2 and 104 V/W at 16 GHz in the case of multilayer MoS$_2$, both achieved without applied DC bias. They are the best performing power detectors fabricated on flexible substrate reported to date. The measured dynamic range exceeds 30 dB outperforming other semiconductor technologies like silicon complementary metal oxide semiconductor (CMOS) circuits and GaAs Schottky diodes.