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Title: Temperature and doping dependent changes in surface recombination during UV illumination of (Al)GaN bulk layers

Abstract

We have studied the effect of continuous illumination with above band gap energy on the emission intensity of polar (Al)GaN bulk layers during the photoluminescence experiments. A temporal change in emission intensity on time scales from seconds to hours is based on the modification of the semiconductor surface states and the surface recombination by the incident light. The temporal behavior of the photoluminescence intensity varies with the parameters such as ambient atmosphere, pretreatment of the surface, doping density, threading dislocation density, excitation power density, and sample temperature. By means of temperature-dependent photoluminescence measurements, we observed that at least two different processes at the semiconductor surface affect the non-radiative surface recombination during illumination. The first process leads to an irreversible decrease in photoluminescence intensity and is dominant around room temperature, and the second process leads to a delayed increase in intensity and becomes dominant around T = 150–200 K. Both processes become slower when the sample temperature decreases from room temperature. They cease for T < 150 K. Stable photoluminescence intensity at arbitrary sample temperature was obtained by passivating the analyzed layer with an epitaxially grown AlN cap layer.

Authors:
; ; ; ;  [1]
  1. Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Strasse 4, 12489 Berlin (Germany)
Publication Date:
OSTI Identifier:
22598819
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM NITRIDES; DISLOCATIONS; EPITAXY; EXCITATION; GALLIUM NITRIDES; ILLUMINANCE; LAYERS; PHOTOLUMINESCENCE; POWER DENSITY; RECOMBINATION; SEMICONDUCTOR MATERIALS; SURFACES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K

Citation Formats

Netzel, Carsten, Jeschke, Jörg, Brunner, Frank, Knauer, Arne, and Weyers, Markus. Temperature and doping dependent changes in surface recombination during UV illumination of (Al)GaN bulk layers. United States: N. p., 2016. Web. doi:10.1063/1.4962319.
Netzel, Carsten, Jeschke, Jörg, Brunner, Frank, Knauer, Arne, & Weyers, Markus. Temperature and doping dependent changes in surface recombination during UV illumination of (Al)GaN bulk layers. United States. doi:10.1063/1.4962319.
Netzel, Carsten, Jeschke, Jörg, Brunner, Frank, Knauer, Arne, and Weyers, Markus. Wed . "Temperature and doping dependent changes in surface recombination during UV illumination of (Al)GaN bulk layers". United States. doi:10.1063/1.4962319.
@article{osti_22598819,
title = {Temperature and doping dependent changes in surface recombination during UV illumination of (Al)GaN bulk layers},
author = {Netzel, Carsten and Jeschke, Jörg and Brunner, Frank and Knauer, Arne and Weyers, Markus},
abstractNote = {We have studied the effect of continuous illumination with above band gap energy on the emission intensity of polar (Al)GaN bulk layers during the photoluminescence experiments. A temporal change in emission intensity on time scales from seconds to hours is based on the modification of the semiconductor surface states and the surface recombination by the incident light. The temporal behavior of the photoluminescence intensity varies with the parameters such as ambient atmosphere, pretreatment of the surface, doping density, threading dislocation density, excitation power density, and sample temperature. By means of temperature-dependent photoluminescence measurements, we observed that at least two different processes at the semiconductor surface affect the non-radiative surface recombination during illumination. The first process leads to an irreversible decrease in photoluminescence intensity and is dominant around room temperature, and the second process leads to a delayed increase in intensity and becomes dominant around T = 150–200 K. Both processes become slower when the sample temperature decreases from room temperature. They cease for T < 150 K. Stable photoluminescence intensity at arbitrary sample temperature was obtained by passivating the analyzed layer with an epitaxially grown AlN cap layer.},
doi = {10.1063/1.4962319},
journal = {Journal of Applied Physics},
number = 9,
volume = 120,
place = {United States},
year = {Wed Sep 07 00:00:00 EDT 2016},
month = {Wed Sep 07 00:00:00 EDT 2016}
}
  • We demonstrate state-of-the-art p-type (Al)GaN layers deposited at low temperature (740 °C) by ammonia molecular beam epitaxy (NH{sub 3}-MBE) to be used as top cladding of laser diodes (LDs) with the aim of further reducing the thermal budget on the InGaN quantum well active region. Typical p-type GaN resistivities and contact resistances are 0.4 Ω cm and 5 × 10{sup −4} Ω cm{sup 2}, respectively. As a test bed, we fabricated a hybrid laser structure emitting at 400 nm combining n-type AlGaN cladding and InGaN active region grown by metal-organic vapor phase epitaxy, with the p-doped waveguide and cladding layers grown by NH{sub 3}-MBE. Single-mode ridge-waveguide LD exhibitsmore » a threshold voltage as low as 4.3 V for an 800 × 2 μm{sup 2} ridge dimension and a threshold current density of ∼5 kA cm{sup −2} in continuous wave operation. The series resistance of the device is 6 Ω and the resistivity is 1.5 Ω cm, confirming thereby the excellent electrical properties of p-type Al{sub 0.06}Ga{sub 0.94}N:Mg despite the low growth temperature.« less
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