TY - JOUR
T1 - Characteristics of SrTiO3 field-effect transistors with DyScO3 gate insulators
AU - Nishio, Kazunori
AU - Abe, Takuya
AU - Takahashi, Ryota
AU - Lippmaa, Mikk
PY - 2010/12/1
Y1 - 2010/12/1
N2 - We have developed a top-gate type of field-effect transistor with a single-crystal SrTiO3 channel and a DyScO3 gate insulator stack consisting of an epitaxial interface layer and an amorphous breakdown barrier layer. We show that the zero-bias conductivity of the transistor channel is strongly affected by the presence of charged traps in the amorphous gate insulator. Low off-state current could only be achieved in devices that were fabricated at an oxygen ambient pressure of 10 mTorr. At lower pressures, metallic channel interfaces were obtained, even after postannealing in air. When both epitaxial and amorphous DyScO3 films were grown at 10 mTorr of oxygen, the on/off ratio of the field-effect transistors (FETs) reached 10 6. We argue that when designing oxide FETs, it is necessary to consider not only breakdown characteristics, but also the charged trap density in wide-gap oxide insulators.
AB - We have developed a top-gate type of field-effect transistor with a single-crystal SrTiO3 channel and a DyScO3 gate insulator stack consisting of an epitaxial interface layer and an amorphous breakdown barrier layer. We show that the zero-bias conductivity of the transistor channel is strongly affected by the presence of charged traps in the amorphous gate insulator. Low off-state current could only be achieved in devices that were fabricated at an oxygen ambient pressure of 10 mTorr. At lower pressures, metallic channel interfaces were obtained, even after postannealing in air. When both epitaxial and amorphous DyScO3 films were grown at 10 mTorr of oxygen, the on/off ratio of the field-effect transistors (FETs) reached 10 6. We argue that when designing oxide FETs, it is necessary to consider not only breakdown characteristics, but also the charged trap density in wide-gap oxide insulators.
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U2 - 10.1143/JJAP.49.125701
DO - 10.1143/JJAP.49.125701
M3 - Article
AN - SCOPUS:79551620852
VL - 49
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 12
M1 - 125701
ER -