The writing 鈥?鈥? through BJT effect, and writing 鈥?鈥? by using capacitive coupling, were verified. We demonstrated that, during the holding, the operation mode of the interfaces is an important factor for the best condition for achieving both a higher current sense margin and a longer retention time, which should be with the front gate in accumulation mode and the back gate in depletion mode.
It was also observed that depending on gate bias applied during the hold operation, there are two mechanisms involved in retention time. For less negative gate voltage the retention time is limited by recombination, whereas for more negative gate voltage the generation mechanisms take place.
Moreover, the retention time showed more sensitivity to the back gate voltage than the current sense margin.