Paraelectrical tuning of a charge carrier density as high as 1013\,cm−2 in the presence of a high electronic carrier mobility on the delicate surfaces of correlated oxides, is a key to the technological breakthrough of a field effect transistor (FET) utilising the metal-nonmetal transition. Here we introduce the Parylene-C/Ta2O5 hybrid gate insulator and fabricate FET devices on single-crystalline SrTiO3, which has been regarded as a bedrock material for oxide electronics. The gate insulator accumulates up to ∼1013cm−2 carriers, while the field-effect mobility is kept at 10\,cm2/Vs even at room temperature. Further to the exceptional performance of our devices, the enhanced compatibility of high carrier density and high mobility revealed the mechanism for the long standing puzzle of the distribution of electrostatically doped carriers on the surface of SrTiO3. Namely, the formation and continuous evolution of field domains and current filaments.
@article{arxiv.1305.1440,
title = {Enhanced and continuous electrostatic carrier doping on the SrTiO$_{3}$ surface},
author = {Azar B. Eyvazov and Isao H. Inoue and Pablo Stoliar and Marcelo J. Rozenberg and Christos Panagopoulos},
journal= {arXiv preprint arXiv:1305.1440},
year = {2013}
}