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Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
Analysis of the hump phenomenon and needle defect states formed by driving stress in the oxide semiconductor
Hyeon-Jun Lee1, Katsumi Abe2, Hee Yeon Noh3
1Intelligent Devices & Systems Research Group, Institute of Convergence, DGIST, Daegu, 42988, Korea. dear.hjlee@dgist.ac.kr.
Abstract:
The reduction in current ability accompanied by the hump phenomenon in oxide semiconductor thin-film transistors to which high DC voltages and AC drive voltages are applied has not been studied extensively, although it is a significant bottleneck in the manufacture of integrated circuits. Here, we report on the origin of the hump and current drop in reliability tests caused by the degradation in the oxide semiconductor during a circuit driving test. The hump phenomenon and current drop according to two different driving stresses were verified. Through a numerical computational simulation, we confirmed that this issue can be caused by an additional "needle", a shallow (~0.2 eV) and narrow (<0.1 eV), defect state near the conduction band minimum (CBM). This is also discussed in terms of the dual current path caused by leakage current in the channel edge.
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