Methods of forming MIM comprise forming a lower electrode on a semiconductor substrate, forming a lower dielectric layer on the lower electrode, and forming an upper dielectric layer on the lower dielectric layer. The lower dielectric layer may be formed of dielectrics having larger energy band gap than that of the upper dielectric layer. An upper electrode is formed on the upper dielectric layer. The upper electrode may be formed of a metal layer having a higher work function than that of the lower electrode.