Thermal Stability of Er2O3–Al2O3 Thin Films Grown on Si Substrates

The thermal stability of Er2O3 and Al2O3 doped Er2O3 thin films deposited on Si substrates has been investigated by x-ray diffraction and x-ray photoelectron spectroscopy. The structures for the as-grown Er2O3 and Al2O3 doped Er2O3 films on Si substrates are found to convert from amorphous to polycrystalline at the annealing temperatures above 450 °C in O2 ambience. The crystallinity and the surfaces roughness of Er2O3 thin films on p-type Si (001) substrates are decreased if Al2O3 is doped in them. However, the result is complicated if these Er2O3 and Al2O3 doped Er2O3 thin films deposited on n-type Si(001) substrates.