@article {Jin2016, title = {Interpreting anomalies observed in oxide semiconductor TFTs under negative and positive bias stress}, journal = {AIP Advances}, volume = {6}, number = {8}, year = {2016}, note = {

cited By 0

}, abstract = {

Oxide semiconductor thin-film transistors can show anomalous behavior under bias stress. Two types of anomalies are discussed in this paper. The first is the shift in threshold voltage (VTH) in a direction opposite to the applied bias stress, and highly dependent on gate dielectric material. We attribute this to charge trapping/detrapping and charge migration within the gate dielectric. We emphasize the fundamental difference between trapping/detrapping events occurring at the semiconductor/dielectric interface and those occurring at gate/dielectric interface, and show that charge migration is essential to explain the first anomaly. We model charge migration in terms of the non-instantaneous polarization density. The second type of anomaly is negative VTH shift under high positive bias stress, with logarithmic evolution in time. This can be argued as electron-donating reactions involving H2O molecules or derived species, with a reaction rate exponentially accelerated by positive gate bias and exponentially decreased by the number of reactions already occurred. {\textcopyright} 2016 Author(s).

}, doi = {10.1063/1.4962151}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84984677284\&partnerID=40\&md5=f3cff1341caca5041c8a817faa91e99f}, author = {Jin, J.W.a , Nathan, A.b , Barquinha, P.c , Pereira, L.c , Fortunato, E.c , Martins, R.c , Cobb, B.d} }