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Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating.

ABSTRACT: The spinodal decomposition and thermal stability of thin In_0.72Al_0.28N layers and In_0.72Al_0.28N/AlN superlattices with AlN(0001) templates on Al₂O₃(0001) substrates was investigated by in-situ heating up to 900?°C. The thermally activated structural and chemical evolution was investigated in both plan-view and cross-sectional geometries by scanning transmission electron microscopy in combination with valence electron energy loss spectroscopy. The plan-view observations demonstrate evidence for spinodal decomposition of metastable In_0.72Al_0.28N after heating at 600?°C for 1?h. During heating compositional modulations in the range of 2-3 nm-size domains are formed, which coarsen with applied thermal budgets. Cross-sectional observations reveal that spinodal decomposition begin at interfaces and column boundaries, indicating that the spinodal decomposition has a surface-directed component.

SUBMITTER: Palisaitis J

PROVIDER: S-EPMC5349532 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating.

Palisaitis J J Hsiao C-L CL Hultman L L Birch J J Persson P O Å PO

Scientific reports 20170314

The spinodal decomposition and thermal stability of thin In0.72Al0.28N layers and In0.72Al0.28N/AlN superlattices with AlN(0001) templates on Al2O3(0001) substrates was investigated by in-situ heating up to 900 °C. The thermally activated structural and chemical evolution was investigated in both plan-view and cross-sectional geometries by scanning transmission electron microscopy in combination with valence electron energy loss s ...[more]

PMID: 28290508

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