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High density of electron trapping in high- \kappa intergate dielectric (IGD) materials remains a major concern for planar memory cells with either poly-Si or hybrid floating gates (FGs). In this paper, for the first time, using the ultrafast I{-}V measurements, it is demonstrated that a significant portion of the P/E windows are actually contributed by electrons trapped initially in the high- \kappa$ IGD stacks during program/erase, and then discharged to FG or control gate during verification. More importantly, it is demonstrated, for the first time, that this fast charge transition can be suppressed using novel multilayer high- $\kappa$ IGD structures, and the fast window instability can be eliminated. [ABSTRACT FROM PUBLISHER]

High-\kappa stacks have been used in the 20-nm generation of floating gate (FG) flash memory cells as the interpoly dielectric (IPD). However, electron trapping in high-\kappa materials remains a major concern for the further development of FG technology. For conventional FG cells, read/pass disturbance in the erased states is a major issue. In this paper, for the first time, it is observed that electron trapping/detrapping in the high-\kappa IPD layers can cause severe abnormal read/pass disturbances in the programmed states. Extensive evidence shows that this instability in programmed states originates from several competing mechanisms, including the redistribution of electron trapping between the IPD and FG and the electron discharging from FG/IPD into the control gate. This issue should be addressed in the development of future generations of FG Flash technology with higher-\kappa IPD materials. [ABSTRACT FROM PUBLISHER]

\Al2\O3 high- \kappa stack is a strong candidate as the dielectric layer in Flash memory cells for technology generations beyond sub-20 nm. In this paper, the cause of abnormal VTH/VFB shift at low operating electric fields is investigated, i.e., VTH/VFB reduces at low positive gate biases and increases at low negative gate biases. It is found that this instability does not originate from the electrons trapping/detrapping from the gate nor from the dielectric relaxation. For the first time, extensive experimental evidences show that this shift is caused by as-grown mobile charges in \Al2\O3 layers generated by postdeposition annealing at 1000 ^\circ\C or above. Its impacts on program/erase windows and read/pass disturbance in Flash memory cells are also evaluated. [ABSTRACT FROM PUBLISHER]