Normally-Off Operation of Lateral Field-Effect Transistors Fabricated from Ultrapure GaN/AlGaN Heterostructures

Research output: Contribution to journalResearch articleContributedpeer-review


  • Stefan Schmult - , Chair of Nanoelectronics (Author)
  • Steffen Wirth - , Max Planck Institute for Chemical Physics of Solids (Author)
  • Victor V. Solovyev - , RAS - Institute of Solid State Physics (Author)
  • Rico Hentschel - , Dresden University of Technology (Author)
  • Andre Wachowiak - , Dresden University of Technology (Author)
  • Tobias Scheinert - , Dresden University of Technology (Author)
  • Andreas Großer - , Dresden University of Technology (Author)
  • Igor V. Kukushkin - , RAS - Institute of Solid State Physics, Higher School of Economics (Author)
  • Thomas Mikolajick - , Chair of Nanoelectronics, Dresden University of Technology (Author)


The presence of a 2D electron gas (2DEG) in GaN/AlxGa1–xN heterostructures with low aluminum mole fraction is found to depend on the residual background impurity concentration in the GaN/AlGaN layer stack. At a residual donor level of 2 × 1016 cm−3, a 2DEG is absent at 300 K in dark environment. Such a 2DEG can be generated at the GaN/AlGaN interface either by illumination with ultraviolet light or by applying an electrostatic potential. The latter results in inherently normally-off switching characteristics of lateral field-effect transistors.


Original languageEnglish
Article number1900732
JournalPhysica Status Solidi (A) Applications and Materials Science
Issue number7
Publication statusPublished - 1 Apr 2020

External IDs

ORCID /0000-0003-3814-0378/work/142256216



  • 2D electron gas, molecular beam epitaxy growth, normally-off field-effect transistor, ultra-pure GaN/AlGaN heterostructrues