XPS method as a useful tool for studies of quantum well epitaxial materials: Chemical composition and thermal stability of InGaN/GaN multilayers

• Published in: Journal of alloys and compounds Vol. 597; pp. 181 - 187
• Main Authors: Lisowski, Wojciech, Grzanka, Ewa, Sobczak, Janusz W., Krawczyk, Mirosław, Jablonski, Aleksander, Czernecki, Robert, Leszczyński, Michał, Suski, Tadeusz
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 05.06.2014; Elsevier
• Subjects: Composition fluctuations; Condensed matter: structure, mechanical and thermal properties; Crystal grown; Exact sciences and technology; Inorganic materials; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Photoelectron spectroscopies; Physics; Quantum wells; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Photoelectron spectroscopies; Crystal grown; Composition fluctuations; Inorganic materials; Quantum wells; Annealing; Barrier layer; Ion beam sputtering; Interdiffusion; High temperature; Gallium nitride; Thermal stability; Thickness; MOVPE method; Chemical composition; Indium nitride; Depth profiles; X-ray photoelectron spectra
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.02.007

•The InGaN multi quantum wells (MQWs) were investigated using the XPS technique.•Both the InGaN QWs and GaN barriers parameters were well characterized.•The interdiffusion of In within the GaN barriers induced by annealing was detected.•The XPS depth profiling analysis is useful to optimize the growth of InGaN/GaN MQWs. The XPS technique combined with low energy Ar+ ion sputter depth profiling was used to obtain information about chemical composition and reproducibility of the growth procedure by the MOVPE method of the InGaN multi quantum wells (MQWs). A good in-depth resolution of the XPS depth profiling technique, allows observation of InGaN quantum wells with thickness down to 2nm. However quantitative characterization of very narrow QWs is limited by the elemental detection range of the XPS analysis. Both the InGaN QWs and GaN barriers parameters were well characterized using the model MQWs samples with various QW thickness. Inter-diffusion of indium within the GaN barrier layers, induced by high-temperature annealing, has been detected. This work evidences the successful application of the XPS depth profiling analysis as a very useful tool to optimize the growth parameters and thermal stability of InGaN/GaN MQWs.