Tuning the Interface Conductivity of LaAlO3/SrTiO3 Using Ion Beams: Implications for Patterning

01 Nov 2013


The two-dimensional electron gas (2DEG) formed at the interface between two semiconductors LaAlO3 and SrTiO3 is an exciting system to explore the physics of correlated electron systems and the basis for some of the most useful electronic devices. The success of any material system for semiconductor applications depends a reliable scaling to fabricate device structures. The deposition conditions along with the buried nature of the 2DEG in LaAlO3/SrTiO3 limit the use of conventional lithography with polymer-resists and RIE/chemical etching.

Here we demonstrate a resist-free single step direct patterning of the interface 2DEG in LaAlO3/SrTiO3 by tailoring the defects in the substrate SrTiO3 using low Z ion beam exposure. This method is tunable to engineer the conductivity of the two-dimensional electron gas at the LaAlO3/SrTiO3 interface by inducing localizations via defects, as evidenced by Electrical transport, Raman spectroscopy and Spectroscopic ellipsometry measurements.

Published By

Sinu Mathew, Anil Annadi, Taw Kuei Chan, Teguh Citra Asmara, Da Zhan, Xiao Renshaw Wang, Sara Azimi, Zexiang Shen, Andrivo Rusydi, Mark B. H. Breese, and T. Venkatesan*