High Mg activation in implanted GaN by high temperature and ultrahigh pressure annealing
Abstract
We demonstrate high p-type conductivity and hole concentrations >1018 cm−3 in Mg-implanted GaN. The implantation was performed at room temperature and by post-implantation annealing at 1 GPa of N2 and in a temperature range of 1200–1400 °C. The high pressure thermodynamically stabilized the GaN surface without the need of a capping layer. We introduce a “diffusion budget,” related to the diffusion length, as a convenient engineering parameter for comparing samples annealed at different temperatures and for different times. Although damage recovery, as measured by XRD, was achieved at relatively low diffusion budgets, these samples did not show p-type conductivity. Further analyses showed heavy compensation by the implantation-induced defects. Higher diffusion budgets resulted in a low Mg ionization energy (∼115 meV) and almost complete Mg activation. For even higher diffusion budgets, we observed significant loss of Mg to the surface and a commensurate reduction in the hole conductivity. High compensation at low diffusion budgets and loss of Mg at high diffusion budgets present a unique challenge for shallow implants. A direct control of the formation of compensating defects arising from the implantation damage may be necessary to achieve both hole conductivity and low Mg diffusion.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 11, 2021
- Source ID
- 10.1063/5.0038628
Entities
People
- Dennis Szymanski
- James Tweedie
- Kacper Sierakowski
- M. Hayden Breckenridge
- Michal Boćkowski
- Pegah Bagheri
- Pramod Reddy
- Ramón Collazo
- Seiji Mita
- Yan Guan
- Zlatko Sitar
Organizations
- Air Force Office of Scientific Research
- National Science Centre Poland
- National Science Foundation
- North Carolina State University
- Polish Academy of Sciences
- United States Department of Energy