Gate oxide induced switch-on undershoot current observed in thin-film transistors

The transient drain current of the single-grain silicon thin-film transistor with gate oxide deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition has been measured by applying a square signal on the gate and a constant low voltage between source and drain. Switch-on undershoot current has been observed, which can be attributed to the motion of space charge in gate oxide. Assuming there are some mobile ions in the gate oxide, we find the drift kinetics of the ions is quite similar to the mobile protons in SiO2, as reported in the literature. (c) 2005 American Institute of Physics.