Nand flash memory device having contact for controlling well potential

Has a well potential control contact is started with respect to the NAND flash memory device. NAND flash memory device according to the invention extends above the first well in the substrate extending in a first direction and so as to intersect the plurality of active regions and a plurality of active regions of the line shape in the the first well is formed in the second direction It includes a pair of dummy word line that is. A pair of dummy word lines are formed of each other by a predetermined first dummy word line that are spaced apart by a distance and a second dummy word line. A first dummy word line and the second dummy word line is always held in a state applied with a bias voltage of 0 V, part is positioned between the plurality of the active region a first dummy word line and the second dummy word line is its activity the rest of the region is electrically independent. The active region is located between the first dummy word line and the second dummy word line has a bias contact for applying the well bias voltage to the first well is formed. NAND, a bias is applied for contact, double patterning, trimming, dummy word line