We have fabricated SrTi O3 (100) single crystal field-effect transistors with epitaxial and amorphous DySc O3 gate insulator layers. The devices showed an on-off ratio of 107 with a field-effect mobility of over 100 cm2 V s at 50 K. The residual oxygen vacancy concentration in the transistor channel was adjusted so that the off-state current was high at room temperature but dropped sharply upon cooling. The temperature dependence of the channel current under a carrier-depleting gate bias was used to show that oxygen vacancies form an in-gap impurity state at about 0.24 eV below the SrTi O3 mobility edge.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)