1. A method of programming a target memory cell of a NAND string of memory cells, comprising the steps of: applying a programming voltage, substantially equal to a programmed initial programming voltage, to the target memory cell, the initial programming voltage being determined and programmed into a memory device that includes the NAND string after fabrication of the memory device; determining whether the target memory cell is programmed; and when it is determined that the target memory cell is not programmed, increasing the programming voltage by a step voltage stored in the memory device, the step voltage being determined and stored in the memory device after fabrication of the memory device.