Relaxation effect on cycling on NOR flash memories

This study is driven by the need to improve endurance of Flash memory. First of all, relaxation during cycling is performed at high temperature. An effect of relaxation has been noticed on erased threshold voltage at high temperature whereas at room temperature, no effect of relaxation is observed. Relaxation implies a recovery of interface state. Then, an experiment of retention after cycling is achieved. At equivalent relaxation time, trap density remains lower for experiment with delay during cycling than for delay after cycling.