A 800 V β‐Ga₂O₃ Metal–Oxide–Semiconductor Field‐Effect Transistor with High‐Power Figure of Merit of Over 86.3 MW cm⁻²

Abstract

Herein, a high‐performance β‐gallium oxide (β‐Ga2O3) metal–oxide–semiconductor field‐effect transistor (MOSFET) on sapphire substrate with a high breakdown voltage of more than 800 V and a high‐power figure of merit of more than 86.3 MV cm−2 is demonstrated. The atomic force microscopy (AFM) image and Raman peaks that are first characterized to ensure a nanomembrane with high quality are used for the device fabrication. A saturation drain current of 231.8 mA mm−1, an RON,sp of 7.41 mΩ cm2, an ON/OFF ratio of 108, and a subthreshold swing of 86 mV dec−1 are obtained at a channel doping concentration of 4.47 × 1017 cm−3 and a source‐to‐drain distance of 11.4 μm. Furthermore, a high breakdown voltage over 800 V is also achieved, corresponding to a record‐high direct current (DC) power figure of merit of 86.3 MW cm−2. Technology computer aided design (TCAD) simulation is also performed to extract the distribution of the electric field along the β‐Ga2O3 channel surface.

Investigation of β‐Ga2O3 Film Growth Mechanism on c‐Plane Sapphire Substrate by Ozone Molecular Beam Epitaxy

“…Monoclinic gallium oxide (β‐Ga 2 O 3 ) is an attractive semiconductor material because of its wide direct bandgap (4.9 eV), excellent chemical and thermal stabilities. [ 1,2 ] β‐Ga 2 O 3 have demonstrated excellent performance, such as, large breakdown field (theoretical value ~8 MV cm −1 ), [ 3 ] high transmittance in ultraviolet region (80%) [ 4 ] and large Baliga's figure of merit (FOM) (3444). [ 5 ] These properties indicate that β‐Ga 2 O 3 is a potential material for applications in gas sensors, [ 6 ] solar‐blind ultraviolet photodetectors, [ 7,8 ] Schottky barrier diode (SBD), [ 9 ] metal oxide semiconductor field‐effect transistors (MOSFETs), [ 10,11 ] etc.…”

Bandgap Tailoring of Monoclinic Single‐Phase β‐(AlxGa1−x)2O3 (0 ≤ x ≤ 0.65) Thin Film by Annealing β‐Ga2O3/Al2O3 Heterojunction at High Temperatures

“…

Recently, β-Ga 2 O 3 has attracted extensive attention because of its ultrawide bandgap (%4.8 eV), [1,2] high theoretical breakdown electric field (E br ) (8 MV cm À1 ), [3,4] and higher Baliga figure of merit (BFOM) compared with GaN and SiC. The highly mature bulk growth and thin film deposition techniques [5][6][7] make both homo- [8][9][10] and heteroepitaxial [11,12] growth of Ga 2 O 3 thin films with controllable doping possible, [13][14][15][16] which is important for practical applications such as power switches, [17,18] high-efficiency devices, [19] and deep-UV photodetectors.

…”

Impact of Different Gate Metals on the RF Performance of Gallium Oxide MOSFET

“…Then, the minimum metal-1 thickness is chosen to ensure that the metal combination has band aligned structure. Now, the thickness of the metal stacks is obtained from the experimentally calibrated bi-metal gate contacts of the references 8,21 by ensuring that the metal combination is band aligned using Eq. 1.…”

“…To overcome the issue related to the good gate electrode material for gallium oxide MOS devices, several researches already have been carried out. [20][21][22][23] 8 ) which can withstand a breakdown voltage of 800 V. 21 These research works only demonstrate the performance of different metal gate based Ga 2 O 3 MOSFET for logic applications and high-power applications. The use and performance of different metal gate based Ga 2 O 3 MOSFET in RF applications has not been demonstrated yet.…”