The structure and properties of HfO2 films deposited by plasma assisted reactive pulsed laser deposition and annealed in N2 were studied upon thermal annealing as well as the evaluation of thermal stability by Fourier transform infrared spectroscopy, spectroscopic ellipsometry, and optical transmission measurements. The as-deposited HfO2 films appear predominantly monoclinic with an amorphous matrix which becomes crystallized after high-temperature annealing. No interfacial SiOx is observed for the as-deposited films on Si. The deposited HfO2 films exhibit good thermal stability and show excellent transparency in a wide spectral range with optical band gap energies of 5.65–5.73 eV depending on annealing temperature. An improvement in the optical properties by high-temperature annealing is also observed.

Photoluminescence (PL) properties of SiOx thin films deposited by pulsed laser ablation of Si in a reactive oxygen ambient and annealed in a nitrogen atmosphere were studied at room temperature. Raman spectroscopy, Fourier transform infrared spectroscopy, and optical transmission measurements were used to characterize the deposited films before and after annealing and complement the PL studies. Strong PL due to quantum confinement was observed at room temperature from Si nanocrystals with an average diameter of approximately 5 nm at 325-nm light excitation. An apparent dependence of PL on the oxygen pressure for film deposition was observed. A detailed analysis of the effects of the annealing temperature revealed a significant PL evolution in luminescence intensity, spectrum profile, peak position, and spectrum range with the annealing temperature ranging from 300 to 1200 °C. Structural variations induced by thermal annealing of the films deposited at different oxygen pressures were also discussed on the basis of their correlation with the PL evolution.

Carbon nitride nanocrystals were synthesized on Co/Ni-covered Si(100) wafers using a nitrogen-atom-beam-assisted pulsed laser ablation deposition method. Transmission electron miscroscopy, x-ray diffraction, and Raman spectroscopy showed that as-deposited films were constructed primarily from nanometer-sized β-C3N4 and CNx crystallites. The co-catalyzation by the cobalt and nickel in the synthesis process is considered to play an important role in the formation of nanocrystalline β-C3N4. The reasons for the formation of carbon nitride nanocrystals were analyzed.