Open AccessEffects of protons within SiO2 solid-state electrolyte on performances of oxide electric-double-layer thin film transistor
Author(s) -
Wenhao Guo,
Hui Xiao,
Chuanling Men
Publication year - 2015
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.64.077302
Subject(s) - materials science , thin film transistor , electrolyte , threshold voltage , hysteresis , optoelectronics , shadow mask , transistor , thin film , electrode , capacitance , indium , electric field , layer (electronics) , voltage , nanotechnology , condensed matter physics , electrical engineering , optics , chemistry , physics , engineering , quantum mechanics
SiO2-based solid state electrolyte films are deposited at room temperature by using the plasma-enhanced chemical vapor deposition (PECVD) technique. An electric-double-layer (EDL) effect has been observed. Then, indium-zinc-oxide thin-film transistors (IZO TFTs) are fabricated by using such SiO2 films as dielectrics in a self-assembling process through a shadow mask. The IZO films for source/drain electrodes and channel are deposited on the nanogranular SiO2 film by RF sputtering the IZO target in an Ar ambient. Such TFTs exhibit a good performance at an ultralow operation voltage of 1.5 V, with a high field-effect mobility of 11.9 cm2/Vs, a small subthreshold swing of 94.5 mV/decade, and a large current on-off ratio of 7.14×106. Effects of protons in the SiO2-based solid state electrolyte films on the electrical performances of the IZO TFTs are also studied. It is observed that a big EDL capacitance can be obtained for SiO2 films dipped in pure water, as a result of the fact that there are more protons in such SiO2 films. Because of the migration of protons in SiO2 electrolytes, an anti-clockwise hysteresis is observed on the transfer curve. Moreover, a bigger hysteresis is observed at a higher gate voltage scan rate. Gate bias stressing stabilities are also studied the shifts in threshold voltage are observed to obey a stretched exponential function.