High n-type conductivity and carrier concentration in Si-implanted homoepitaxial AlN

• Published in: Applied physics letters Vol. 118; no. 11
• Main Authors: Breckenridge, M. Hayden, Bagheri, Pegah, Guo, Qiang, Sarkar, Biplab, Khachariya, Dolar, Pavlidis, Spyridon, Tweedie, James, Kirste, Ronny, Mita, Seiji, Reddy, Pramod, Collazo, Ramón, Sitar, Zlatko
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 15.03.2021
• Subjects: Annealing; Applied physics; Carrier density; Dislocation density; Low temperature; Self compensation; Threading dislocations
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/5.0042857

We demonstrate Si-implanted AlN with high conductivity (>1 Ω−1 cm−1) and high carrier concentration (5 × 1018 cm−3). This was enabled by Si implantation into AlN with a low threading dislocation density (TDD) (<103 cm−2), a non-equilibrium damage recovery and dopant activation annealing process, and in situ suppression of self-compensation during the annealing. Low TDD and active suppression of VAl-nSiAl complexes via defect quasi Fermi level control enabled low compensation, while low-temperature, non-equilibrium annealing maintained the desired shallow donor state with an ionization energy of ∼70 meV. The realized n-type conductivity and carrier concentration are over one order of magnitude higher than that reported thus far and present a major technological breakthrough in doping of AlN.