Local vibrational modes and compensation effects in Mg‐doped GaN

Abstract

The compensation and self-compensation effects in Mg-doped GaN is studied by low-temperature photoluminescence and Raman spectroscopy using a series of samples with different Mg concentrations. Strongly doped samples are found to be highly compensated in electrical measurement. The compensation mechanism is directly related to the incorporation of Mg leading to the additional formation of three different deep donor levels. Furthermore, hydrogen forms defect complexes with Mg and compensates the acceptor states. These complexes were observed as local vibrational modes in Raman spectra in the range of 2200 cm -1. The direct incorporation of Mg can be controlled by local vibrational modes in the region of GaN host phonons. Investigating the intensity dependence of the different Mg-H complexes and the LVM of activated Mg the Raman spectra give a clear direct evidence of the degree of compensation and pconductivity.

Quantified hole concentration in AlGaN nanowires for high-performance ultraviolet emitters

“…S2(b), ESI †). 39,[51][52][53][54][55] When T Mg was 440°C, the Mg-related signatures were absent, which was probably due to the different growth modes, i.e., different scattering geometries under this condition. Although we were not able to estimate the Mg concentration for the sample with T Mg = 360°C and 400°C using intensities of LVMs due to the lack of references for the Mg-doped AlGaN study, 39 the Raman results here further affirm the substitutional Mg atoms.…”

Nitrogen‐doped ZnO obtained by nitrogen plasma treatment

“…The LVM frequencies can be estimated using a simple function [27]: The work function is the minimum energy that is needed to remove an electron from a solid to a point outside the solid surface immediately or to move an electron from the Fermi level into vacuum [28]. The relation between work function and Fermi energy level is given in the following equation:…”

Raman scattering study on Ga1–xMnx As prepared by Mn ions implantation, deposition and post‐annealing

“…In our previous study [9], low frequency phonon mode was found at 151 cm -1 in the Raman spectra measured from Ga 1-x Mn x N prepared by Mn ions implantation, deposition and post annealing. Similar low frequency phonon mode was also found [17] at 136 cm -1 in Mg doped GaN crystal and assigned to as a local vibrational mode (LVM) of Mg. The LVM of Mn can be estimated using the simple mass-defect approximated given by Hoffmann et al [17] GaAs LVM LVM GaAs…”

“…Similar low frequency phonon mode was also found [17] at 136 cm -1 in Mg doped GaN crystal and assigned to as a local vibrational mode (LVM) of Mg. The LVM of Mn can be estimated using the simple mass-defect approximated given by Hoffmann et al [17] GaAs LVM LVM GaAs…”