Open AccessThickness Effect on Operational Modes of ZnGa2O4 MOSFETs
Author(s) -
Li-Chung Cheng,
Chiung-Yi Huang,
Ray-Hua Horng
Publication year - 2018
Publication title -
ieee journal of the electron devices society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.69
H-Index - 31
ISSN - 2168-6734
DOI - 10.1109/jeds.2018.2803078
Subject(s) - components, circuits, devices and systems , engineered materials, dielectrics and plasmas
The device mechanism from depletion to enhancement mode for ZnGa2O4 metal-oxide semiconductor field effect transistors (MOSFETs) grown on the sapphire substrate by metalorganic chemical-vapor deposition was studied. It was found that the thickness of the ZnGa2O4 thin-film would affect the operational mode of the MOSFETs. Under the low-voltage operation (VDS = 0.5 V), the transistors exhibited a high on/off ratio from 107 to 104, low subthreshold swing from 150 to 330 mV/dec, high field-effect mobility from 4.2 to 0.054 cm2/V-s and threshold voltages from -17.8 to 4.1 V (using constant current = 1 nA). These electrical properties all depend on the thickness of the ZnGa2O4 thin-film transistors. Finally, the e-mode ZnGa2O4 thin-film transistor with off-state breakdown voltage over 400 V is fabricated.