Band Alignment and Band Gap Characterization of La₂O₃ Films on Si Substrates Grown by Radio Frequency Magnetron Sputtering

La₂O₃ films are grown on Si (100) substrates by the radio-frequency magnetron sputtering technique. The band alignment of the La₂O₃/Si heterojunction is analyzed by the x-ray photoelectron spectroscopy. The valence-band and the conduction-band offsets of La₂O₃ films to Si substrates are found to be 2.40±0.1 and 1.66±0.3 eV, respectively. Based on O 1s energy loss spectrum analysis, it can be noted that the energy gap of La₂O₃ films is 5.18±0.2 eV, which is confirmed by the ultra-violet visible spectrum. According to the suitable band offset and large band gap, it can be concluded that La₂O₃ could be a promising candidate to act as high-k gate dielectrics.