Effects of temperature and oxygen partial pressure on electrical conductivity of Fe-doped β-Ga2O3 single crystals
Abstract
In this work, we measure DC and AC conductivity and Hall voltage to determine the origin of electrical insulating properties of Fe-doped β-Ga2O3 single crystals, which are measured perpendicular to the 2¯01 crystallographic plane. We find that electrical conduction is predominantly controlled by free electrons in the temperature range 230–800 °C with the mutual compensation of the impurity donor (Si) and acceptor dopant (Fe), explaining the low concentration of free electrons and Fermi level pinning over a wide range of temperatures. Furthermore, the negative temperature-dependence of the carrier mobility indicates that it is limited by optical phonon scattering. Importantly, we find electrical conductivity to be largely independent of oxygen partial pressure (pO2) from air to 10−4 atm at 600 °C, but it becomes slightly dependent on pO2 at 800 °C, as intrinsic non-stoichiometric point defects begin to influence the charge balance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 02, 2022
- Source ID
- 10.1063/5.0093588
Entities
People
- Elizabeth C Dickey
- Gyung Hyun Ryu
- Pramod Reddy
- Ramón Collazo
Organizations
- Air Force Office of Scientific Research
- Carnegie Mellon University
- National Science Foundation
- North Carolina State University
- Pennsylvania State University