Space-charge-limited current conductions in La2O3 thin films deposited by e-beam evaporation after low temperature dry-nitrogen annealing [gate oxide applications]

Lanthanum oxide (La₂O₃) was deposited by e-beam evaporation on n-Si(100), and annealed at 200°C in dry-nitrogen ex-situ for 5 min. From the applied voltage and temperature dependences of the current of the gate oxide, it has been shown that the main conduction mechanisms are SCLC (space-charge-limited current) and Schottky conductions at low and high applied voltages, respectively. Trap levels in the oxide band gap, composed of both exponential and localized distributions, were extracted by using the differential method. The dielectric constant obtained from Schottky conduction was 27 and was consistent with the C-V results.