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

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

doi:10.1038/srep44390

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

Sci Rep. 2017 Mar 14:7:44390. doi: 10.1038/srep44390.

Authors

J Palisaitis¹, C-L Hsiao¹, L Hultman¹, J Birch¹, P O Å Persson¹

Affiliation

¹ Thin Film Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden.

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.

Publication types

Research Support, Non-U.S. Gov't