Interfaces in La_1.89Ce_0.11CuO₄/Ba_0.5Sr_0.5TiO₃/La_0.88Sr_0.12MnO₃ heterostructures on (0 0 1) SrTiO₃ substrates

Abstract

High-quality La_1.89Ce_0.11CuO₄/Ba_0.5Sr_0.5TiO₃/La_0.88Sr_0.12MnO₃ heterostructures grown on SrTiO₃ enable a variety of electronic devices. The performance of such devices depends strongly on the interfacial microstructure of the heterostructures. Here, we use high-resolution transmission electron microscopy to reveal the structure and microstructure of La_1.89Ce_0.11CuO₄/Ba_0.5Sr_0.5TiO₃/La_0.88Sr_0.12MnO₃ heterostructures. A step at the interface between La_1.89Ce_0.11CuO₄ and Ba_0.5Sr_0.5TiO₃ layers is found to have a height of about 1.36 nm. The interfacial structures on both sides of the step at the atomic level are revealed by image processing and image simulation. Major defects in the Ba_0.5Sr_0.5TiO₃ and La_0.88Sr_0.12MnO₃ layers are dislocations with a Burgers vector of a [1 0 0].

Keywords:

• heterostructures
• HRTEM
• interfacial structures
• image processing
• dislocations

Acknowledgements

The authors thank Miss Y. Li for her help in sample preparations.

Funding

This project is supported by the National Natural Science Foundation of China [grant number 51102275] and the Special Funds for Major State Basic Research Projects [grant number 2010CB934200].