A novel band-to-band tunneling induced convergence mechanism for low current, high density flash EEPROM applications

摘要

A new low current two-step erasing scheme for "repairing" over-erased flash EEPROM cells has been developed. The cell convergence is achieved with 10 V on the control gate and 5 V on the source and drain for 50 ms. The convergence current is kept to below 1 nA per cell. A substrate BTBT tunneling induced hot electron injection mechanism is proposed for convergence. No significant oxide degradation is seen in the method.