High Al-Content AlGaN Transistor With 0.5 A/mm Current Density and Lateral Breakdown Field Exceeding 3.6 MV/cm

Bajaj S., ALLERMAN A., ARMSTRONG A., Razzak T., Talesara V., Sun W., ...More

IEEE ELECTRON DEVICE LETTERS, vol.39, no.2, pp.256-259, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 39 Issue: 2
  • Publication Date: 2018
  • Doi Number: 10.1109/led.2017.2780221
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.256-259
  • Keywords: Ultra wide bandgap, AlGaN, high Al composition, AlGaN MOSFET, high breakdown field, high Al-content, ELECTRON-MOBILITY TRANSISTORS, OPERATION, TRANSPORT, SAPPHIRE, HEMTS, GAN
  • Yıldız Technical University Affiliated: No


We report on ultra-wide bandgap (UWBG) Al0.7Ga0.3N channel metal-oxide-semiconductor field-effect transistors (MOSFETs) grown by metal-organic chemical vapor deposition. Employing reverse Al composition graded ohmic contact layers and 20 nm Al2O3 gate-dielectric, 250 nm thick Al0.7Ga0.3N: Si channel MOSFETs resulted in the maximum current density of 0.5 A/mm, which is the highest value reported for AlGaN channels with Al composition >0.25. Transistors with a gate-drain spacing (LGD) of 1.7 mu m demonstrated a breakdown voltage (VDG) of similar to 620 V, translating in an average lateral breakdown field of similar to 3.6 MV/cm. This work establishes UWBG AlGaN as a promising candidate for advanced RF applications.