Microstructure and optical properties of Gd2O3 thin films prepared by pulsed laser deposition

• Crystalline Gd2O3 films were prepared at or above 473 K by pulsed laser deposition.
• Structural properties of the films investigated by XRD, Raman and TEM show mostly monoclinic phase.
• Substrate temperature, oxygen partial pressure and film thickness influence the phase formation.
• The Gd2O3 film deposited at 873 K shows the highest band gap of 5.80 eV.

Gadolinium oxide (Gd2O3) thin films were deposited on Si (100) and quartz substrates at different substrate temperatures (300–873 K) and oxygen partial pressures (0.002–2 Pa) by pulsed laser deposition technique. The microstructure of the films was analyzed by X-ray diffraction (XRD), atomic force microscopy and Raman spectroscopy. The XRD pattern shows the presence of monoclinic phase of Gd2O3 as a major phase along with a small volume fraction of cubic phase at lower substrate temperatures. Optical transmittance and absorbance of the Gd2O3 films were measured by UV–visible spectrophotometer. The films deposited at different deposition conditions show a strong absorbance at ~ 220 nm and exhibit transmittance in the range of 70–90%. Highest value of band gap (~ 5.80 eV) is obtained for the Gd2O3 film deposited at 873 K.