[en] GaN:Mg ; Deep impurity ; Dopant ; Admittance spectroscopy
[en] The effect of the deep acceptor Mg on the electrical characteristics of p-doped GaN Schottky diodes is analyzed. The theoretical study is based on the numerical resolution of the basic semiconductor equations, including the continuity equation for the Mg-related acceptor level. It gives the steady-state and small-signal analysis of p-doped GaN:Mg Schottky diodes, yielding as final result the frequency dependent capacitance and conductance of the structure. It is shown that the low-frequency characteristics are determined by the carrier exchange between the Mg related impurity level and the valence band, whereas above the impurity transition frequency, the hole modulation of the depletion layer edge governs the electrical response. Detailed results are shown on the effect of temperature, applied steady-state voltage and series resistance. The study of two back-to-back connected GaN Schottky diodes reveals the appearance of typical features in the electrical characteristics, depending on the respective Schottky barrier height of the two junctions.
Copyright (year) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics and may be found at http://link.aip.org/link/JAPIAU/v89/i3/p1890/s1.