A non-volatile memory device includes a field region that defines an active region in a semiconductor substrate, a floating gate pattern on the active region, a dielectric layer on the floating gate pattern and a control gate on the dielectric layer. The control gate includes a first conductive pattern that has a first composition that crystallizes in a first temperature range, and a second conductive pattern that has a second composition that is different from the first composition and that crystallizes in a second temperature range that is lower than the first temperature range, the first conductive pattern being between the dielectric layer and the second conductive pattern.