A non-volatile memory device includes a first oxide layer, a second oxide layer and a buffer layer formed on a lower electrode. An upper electrode is formed on the buffer layer. In one example, the lower electrode is composed of at least one of Pt, Ru, Ir, IrOx and an alloy thereof, the second oxide layer is a transition metal oxide, the buffer layer is composed of a p-type oxide and the upper electrode is composed of a material selected from Ni, Co, Cr, W, Cu or an alloy thereof.