Metal-oxide-semiconductor capacitors with Sm2O3 dielectric film were fabricated and the temperature dependence of the conduction mechanisms was studied. The Sm2O3 films were deposited by radio frequency magnetron sputtering. The thickness of Sm2O3 was 18.8 nm. The dielectric permittivity and the equivalent oxide thickness of capacitors with Sm2O3 film were 15.0 and 4.8 nm, respectively. The X-ray photoelectron spectroscopy analysis showed a silicate interfacial layer formed between Sm2O3 and Si. When the aluminum electrode was biased positive, the dominant conduction mechanism was Schottky emission in the temperature range 475 K < T < 500 K and at an electrical field of 0.8 MV/cm < E < 1.4 MV/cm. In the temperature range 300-425 K, the dominant conduction mechanism was most likely space-charge-limited conduction. When the aluminum electrode was biased negative, the dominant conduction mechanism in the temperature range from 325 to 500 K and at an electrical field from 0.08 to 0.81 MV/cm was Schottky emission. At 77 K and with the electrical field above 0.9 MV/cm, the conduction mechanism was Fowler-Nordheim (F-N) tunneling. The Al/Sm2O3 electron barrier height and the effective electronic mass calculated from Schottky emission and F-N tunneling were 0.82 eV and 0.13 m(0), respectively. (c) 2008 The Electrochemical Society. [ DOI: 10.1149/ 1.2979141] All rights reserved.