| HfO2 is an excellent insulator and has many attractive properties, such as wide band gap, high dielectric constant, high refractive index, good thermal and chemical stablity, etc., so that it can be extensively applied in the electronic and optical devices. HfO2 can be used as a high dieletric layer in MOS device to replace the routine SiO2, so that it can satisfy the need of incresing integration and scaling down size. Because of its high refractive index and transmittance, HfO2 can usually be used as the anti-and high-reflective coatings. In the multi-layer anti-or high-reflective coatings, HfO2 can act as the high refracitve index layer. Moreover, HfO2 is an excellent anti-damage materials in the laser device since its large band gap energy. In this study, HfO2 films were prepared by reactive sputtering at the Si, quartz, K9 glass substrates using the DC, pulsed DC, RF sputtering power, respectively. The impact of the deposition parameters and the auxiliary means, such as substrate temperature, bias voltage, magnetic field, on the quality of HfO2 films was analysised. Moreover, a variety of post-treated mothods had been tried to improve the properties of HfO2 films.The as-sputtered and post-treated HfO2 films were characterized by XRD, SEM, AFM, SE, UV-Vis, XPS, PAS, C-V, I-V, laser induced damage threshold. The results showed:(1) HfO2 films were monoclinic phase and consisted of nanocrystall particle. The grain size was in the tens of nanometers and (-111) direction was the staly preferred growth direction. Substrate heating was helpful to obtain the samples consisted of the uniform particles. The surface of the sample was rough and AFM showed the RMS roughness of the samples was in the 2 nm or more, which was influenced by the experimental conditions. The surface of the samples deposited at substrate bias will become rougher.(2) The samples had a high refractive index in the 1.8-2.1 range, indicating that the samples were dense. Appropriate Substrate heating and magnetic field could help to obtain a higher refractive index. The samples deposited at pulse DC power had the higher refractive index. In the range of the wavelength greater than 220 nm, all samples had good transmitance higher than 80%. Optical band gap of the samples is up to 5.6 eV or more.(3) XPS results showed that the sputtered samples had the fewer impurities. By reactive sputtering method, the stoichiometric film can be obtained. The RF power was more favor to deposite the stoichiometric samples.(4) The defects in the samples deposited under the different experimental conditions were characterized by PAS. The results showed:at the pulse power supply, low O2/(O2+Ar) ratio, relatively high pressure and power Samples favored to the deposition of the samples with lower defect; at RF power, lower pressure, higher O2/(O2+Ar) ratio and power were helpful to deposit the samples with lower defects. Appropriate atomic oxygen treatment could reduce the defects and improve the oxygen content.(5) Electrical measurement found that the leakage current of the samples derived from the defects and grain boundaries and was affected by the sample's structure, such as crystallinity, composition, and so on. The substrate bias applied to sample would deteriorate the film quality and increase the leakage current. Appropriate annealing treatment, would reduce the defects and leakage current and increase the oxygen content in the films. Atomic oxygen treatment would also reduce the defects in the sample.(6) The highest laser damage threshold of the samples was 7.3 J/cm2 at1064 nm and 6.8 ns. The LIDT of the samples deposited by RF power pulse was larger than that prepared at pulsed DC power.
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