A semiconductor device includes a first semiconductor layer, an n-type/p-type second semiconductor layer, p-type/n-type third semiconductor layers and a first gate electrode. The second semiconductor layer is formed on the first semiconductor layer and has an oxidation rate which is lower than that of the first semiconductor layer. The third semiconductor layers are formed in the second semiconductor layer and have a depth reaching an inner part of the first semiconductor layer. In case that the second and third semiconductor layers are n-type and p-type, respectively, a lattice constant of the second semiconductor layer is less than that of the third semiconductor layer. In case that the second and third semiconductor layers are p-type and n-type, respectively, the lattice constant of the second semiconductor layer is greater than that of the third semiconductor layer. A first gate electrode is formed on the second semiconductor layer.