TY - JOUR
T1 - Spatial variation of luminescence of InGaN alloys measured by highly-spatially-resolved scanning catholuminescence
AU - Bertram, F.
AU - Srinivasan, S.
AU - Geng, L.
AU - Ponce, Fernando
AU - Riemann, T.
AU - Christen, J.
AU - Tanaka, S.
AU - Omiya, H.
AU - Nakagawa, Y.
PY - 2001/11
Y1 - 2001/11
N2 - Cathodoluminescence (CL) measurements were performed on a set of thick InGaN layers covering systematically a wide range of indium concentrations (x = 0.03-0.20). These thick InGaN layers are exceptionally specular for low indium concentrations (x < 0.1), while some degree of microscopic roughness is observed for x > 0.1. While in CL mappings the size of the areas with constant emission wavelength decreases with indium content, a similar change of domain size is observed by AFM. For low indium content, statistical fluctuations of the local indium concentration lead to a Gaussian broadening of a single emission line. In contrast, for x > 0.1 phase separation results in a multimodal distribution of the peak wavelength, leading to additional low-energy peaks in CL overview spectra. In highly spatially resolved CL measurements we correlate these low-energy emissions to characteristic structural defects.
AB - Cathodoluminescence (CL) measurements were performed on a set of thick InGaN layers covering systematically a wide range of indium concentrations (x = 0.03-0.20). These thick InGaN layers are exceptionally specular for low indium concentrations (x < 0.1), while some degree of microscopic roughness is observed for x > 0.1. While in CL mappings the size of the areas with constant emission wavelength decreases with indium content, a similar change of domain size is observed by AFM. For low indium content, statistical fluctuations of the local indium concentration lead to a Gaussian broadening of a single emission line. In contrast, for x > 0.1 phase separation results in a multimodal distribution of the peak wavelength, leading to additional low-energy peaks in CL overview spectra. In highly spatially resolved CL measurements we correlate these low-energy emissions to characteristic structural defects.
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U2 - 10.1002/1521-3951(200111)228:1<35::AID-PSSB35>3.0.CO;2-1
DO - 10.1002/1521-3951(200111)228:1<35::AID-PSSB35>3.0.CO;2-1
M3 - Article
AN - SCOPUS:0035541048
SN - 0370-1972
VL - 228
SP - 35
EP - 39
JO - Physica Status Solidi (B) Basic Research
JF - Physica Status Solidi (B) Basic Research
IS - 1
ER -