REPROGRAMMING MEMORY WITH SINGLE PROGRAM PULSE PER DATA STATE

摘要

Techniques are provided for programming memory cells while reducing the effects of detrapping which cause a downshift in the threshold voltage distribution. Detrapping is particularly problematic for charge-trapping memory cells such as in a 3D stacked non-volatile memory device. After completion of a full programming pass, a verify test is performed to identify cells for which reprogramming is warranted. The reprogramming includes a single program pulse for each target data state, where each program pulse is longer than in the full programming pass. The pulse widths can be optimized based on factors such as a programming speed or a threshold voltage distribution width from the full programming pass.