On the conduction mechanism in compositionally graded AlGaN

Abstract

A two-band transport model is proposed to explain electrical conduction in graded aluminum gallium nitride layers, where the free hole conduction in the valence band is favored at high temperatures and hopping conduction in the impurity band dominates at low temperatures. The model simultaneously explains the significantly lowered activation energy for p-type conduction (∼10 meV), a nearly constant sheet conductivity at lower temperatures (200–330 K), and the anomalous reversal of the Hall coefficient caused by the negative sign of the Hall scattering factor in the hopping conduction process. A comparison between the uniform and graded samples suggests that compositional grading significantly enhances the probability of phonon-assisted hopping transitions between the Mg atoms.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 15, 2022
Source ID
10.1063/5.0100756

Entities

People

  • Baxter Moody
  • Dolar Khachariya
  • Ji Hyun Kim
  • Pegah Bagheri
  • Pramod Reddy
  • Ramón Collazo
  • Ronny Kirste
  • Seiji Mita
  • Shashwat Rathkanthiwar
  • Yasutomo Kajikawa
  • Zlatko Sitar

Organizations

  • Air Force Office of Scientific Research
  • Army Research Office
  • National Science Foundation
  • North Carolina State University
  • Shimane University

Tags

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene