Properties of the main Mg-related acceptors in GaN from optical and structural studies

Abstract

), the 3.466 eV ABE1 acceptor bound exciton and the associated 3.27 eV donor-acceptor pair (DAP) band are the only strong photoluminescence (PL) signals at 2 K, and are identified as related to the substitutional Mg acceptor with a binding energy of 0.225 6 0.005 eV, and with a moderate phonon coupling strength. Interaction between basal plane stacking faults (BSFs) and Mg acceptors is suggested to give rise to a second deeper Mg acceptor species, with optical signatures ABE2 at 3.455 eV and a corresponding weak and broad DAP peak at about 3.15 eV. The 2.9 eV PL band has been ascribed to many different processes in the literature. It might be correlated with another deep level having a low concentration, only prominent at high Mg doping in material grown by the Metal Organic Chemical Vapor Deposition technique. The origin of the low temperature metastability of the Mg-related luminescence observed by many authors is here reinterpreted and explained as related to a separate non-radiative metastable deep level defect, i.e., not the Mg Ga acceptor. V C 2014 AIP Publishing LLC. [http://dx

Three-dimensional cathodoluminescence characterization of a semipolar GaInN based LED sample

“…between 2.80 and 3.35 eV, which can be assigned to p-type GaN, e.g., donor-acceptor-pair-transitions and their phonon replicas. [22][23][24] At a calculated penetration depth of 150 nm, the slope of the p-GaN luminescence intensity profile (red solid line) in Fig. 3 decays and finally saturates, because no additional p-GaN is excited with increasing PE energy anymore.…”

Optical properties of C-doped bulk GaN wafers grown by halide vapor phase epitaxy

“…6(c), the DAP emission is rather uniform. Since it is related to the recombination of shallow donors (Si) and acceptors (Mg) 37 and is determined by the number of minority dopant atoms, i.e., Mg, the background concentration of Mg is also uniform.…”

Hysteretic photochromic switching of Eu-Mg defects in GaN links the shallow transient and deep ground states of the Mg acceptor

“…Remarkably, GaN:Mg is one of the very few host-dopant combinations of a p-type wide-gap semiconductor that has matured into a commercial technology. Despite this technological success, the physics of the Mg acceptor states in GaN is still not settled45678910111213. Employing a Koopmans corrected density functional method, Lany and Zunger (L-Z, hereafter) proposed that GaN:Mg has two acceptor states with distinct properties: firstly, a highly non-effective-mass-like acceptor state (the deep ground state, DGS) with a hole localized in one p-orbital of a N neighbour in the basal plane; secondly, an effective-mass-like shallow transient state (STS)7.…”