US Patent 7196930 Flash memory programming to reduce program disturb

The method for reducing program disturb in a flash memory array biases a selected wordline at a programming voltage. One of the unselected wordlines, closer to array ground than the selected wordline, is biased at a voltage that is less than Vpass. The memory cells on this unselected wordline that are biased at this voltage block the gate induced drain leakage from the cells further up in the array. The remaining unselected wordlines are biased at Vpass. In another embodiment, a second source select gate line is added to the array. The source select gate line that is closest to the wordlines is biased at the voltage that is less than Vpass in order to block the gate induced drain leakage from the array.