High-voltage field effect transistors with wide-bandgap β-Ga2O3 nanomembranes

Abstract

Nanoscale semiconductor materials have been extensively investigated as the channel materials of transistors for energy-efficient low-power logic switches to enable scaling to smaller dimensions. On the opposite end of transistor applications is power electronics for which transistors capable of switching very high voltages are necessary. Miniaturization of energyefficient power switches can enable the integration with various electronic systems and lead to substantial boosts in energy efficiency. Nanotechnology is yet to have an impact in this arena.In this work, it is demonstrated that nanomembranes of the wide-bandgap semiconductor gallium oxide can be used as channels of transistors capable of switching high voltages, and at the same time can be integrated on any platform. The findings mark a step towards using lessons learnt in nanomaterials and nanotechnology to address a challenge that yet remains untouched by the field.

Schottky barrier diode based on β-Ga2O3 (100) single crystal substrate and its temperature-dependent electrical characteristics

“…[12][13][14][15][16] Among the five structures of Ga 2 O 3 single crystal, monoclinic b-Ga 2 O 3 is the most stable one. Some preliminary studies on the material growth and power device fabrication and characterization have been carried out in the last several years.…”

Ultrawide‐Bandgap Semiconductors: Research Opportunities and Challenges

“…For thin semiconductors where quantum confinement and bandgap widening occurs, this is extremely important. Indeed, the WBG and UWBG semiconductors have recently sprung a few surprises in the limit of extreme thinness: 2D GaN and quasi-2D Ga 2 O 3 have been fabricated by sublimation or mechanical exfoliation, respectively, [133,179] potentially enabling significant increases in energy gap as fewer monolayers of material are isolated (e.g., 5.28 eV for 2D GaN). These ultrawide bandgaps, comparable even to the 5-6 eV of h-BN, will likely motivate research in advanced techniques for layer-by-layer epitaxial growth of both WBG and UWBG semiconductors.…”

“…Among these routes might be those based on thin-film separation methods or nanomembranes, [133] [136] and possibly various 2D materials, are all of interest.…”

Anisotropic thermal conductivity in single crystal β-gallium oxide

“…Because of the large bandgap and the resultant large electrical breakdown strength, this material can sustain large voltages, making it attractive for high voltage device applications. Recently, β-Ga 2 O 3 Schottky diodes with large reverse breakdown voltages and β-Ga 2 O 3 field-effect transistors sustaining large drain voltages have been demonstrated [1][2][3][4] . In a high-voltage device, most of the power is dissipated in the channel, causing an increase in the channel temperature.…”