Photosensitive inverters and light-to-frequency conversion circuits based on transistion metal dichalcogenides field effect transistors

Sung Hun Jin

Photosensitive inverters and light-to-frequency conversion circuits based on transistion metal dichalcogenides field effect transistors

8^th International Conference on Smart Materials and Structures
August 01-02, 2019 Dublin, Ireland

Sung Hun Jin

Incheon National University, South Korea

Posters & Accepted Abstracts: Nano Res Appl

Abstract

Recently transisiton metal dichalcogenides (TMDCs) such as MoS2, WSe2, MoTe2, WS2 and others haved been emerged and actively researched as one of next generation semiconductors for extending Moore’s law. Among a variety of novel properties for TMDCs, one of interesting properties is to modulate energy bandgap (Eg) in variation of number of layers. In this study, for the improvement of noise immunity for IoT sensor systems, photo sensitive inverters and their light-tofrequency conversion circuts (LFCs) are proposed and experimentally demonstrated by using the platform comprised of an enhancement MoS2 driver with lightshield layers (LSLs) (or GaN FET drivers) and MoS2 depletion load. Moreover, for energy efficient circuits, complementary photo- sensitive inverters based on p-type MoTe2 and n-type MoS2 FETs are demonstrated. For the better understanding on performance of LFCs, we systematically studied basic design rules on LFCs via experimentally measured voltage transfer characteristics of photo-sensitive inverters and their spice simulation with their extracted model parameters based on RPI model (i.e., SILVACO, Smart-spice; level 36). The simulation results illustrate that key parameters of ring osciallators (ROs) such as oscillation frequency (fosc) and peak-to peak voltage (Vp-p) can be systematically controlled by inverter parameters such as noise margin, voltage gains associated with electrical parameters (i.e., Vth, SS, current on/off ratio, field effect mobility, etc). In the present study, experimental implementation of photosensitive inverters based on MoS2, MoTe2, and GaN FETs, etc. and their systematic validation on performance via spice simulation yield insightful design rules required for reliable operation of LFCs, potentially contributing to emerging IoT security systems.