In:
Chinese Physics B, IOP Publishing, Vol. 29, No. 5 ( 2020-05-01), p. 058103-
Abstract:
The Mg acceptor activation mechanism and hole transport characteristics in AlGaN alloy with Mg doping concentration (∼ 10 20 cm −3 ) grown by metal–organic chemical vapor deposition (MOCVD) are systematically studied through optical and electrical properties. Emission lines of shallow oxygen donors and (V III complex) 1− as well as V N 3 + and neutral Mg acceptors are observed, which indicate that self-compensation is occurred in Mg-doped AlGaN at highly doping levels. The fitting of the temperature-dependent Hall effect data shows that the acceptor activation energy values in Mg-doped Al x Ga 1 − x N ( x = 0.23, 0.35) are 172 meV and 242 meV, and the hole concentrations at room temperature are 1.2 × 10 18 cm −3 and 3.3 × 10 17 cm −3 , respectively. Therefore, it is believed that there exists the combined effect of the Coulomb potentials of the dopants and screening of the Coulomb potentials by a high hole concentration. Moreover, due to the high ionized acceptors’ concentration and compensation ratio, the impurity conduction becomes more prominent and the valence band mobility drops sharply at low temperature.
Type of Medium:
Online Resource
ISSN:
1674-1056
DOI:
10.1088/1674-1056/ab7e93
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2020
detail.hit.zdb_id:
2412147-2
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