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Title: Doping and compensation in heavily Mg doped Al-rich AlGaN films

Record low resistivities of 10 and 30 Ω cm and room-temperature free hole concentrations as high as 3 × 1018 cm−3were achieved in bulk doping of Mg in Al0.6Ga0.4N films grown on AlN single crystalline wafer and sapphire. The highly conductive films exhibited a low ionization energy of 50 meV and impurity band conduction. Both high Mg concentration (>2 × 1019cm−3) and low compensation were required to achieve impurity band conduction and high p-type conductivity. The formation of VN-related compensators was actively suppressed by chemical potential control during the deposition process. This work overcomes previous limitations in p-type aluminum gallium nitride (p-AlGaN) and offers a technologically viable solution to high p-conductivity in AlGaN and AlN.

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Award ID(s):
1916800 1653383 1508854
Publication Date:
Journal Name:
Applied Physics Letters
Page Range or eLocation-ID:
Article No. 082102
American Institute of Physics
Sponsoring Org:
National Science Foundation
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