| In this thesis, using radio-frequency magnetron reactive sputtering technique (RF sputtering), a series of single-phased Ag2Ofilms were deposited on glass substrates by changing the oxygen flux rate (OFR=[O2]/[Ar]), substrate temperature (T) and sputtering power (P). Effects of the OFR, T and P were intensively studied on the films'microstructure and optical properties. The film's microstructure and surface morphology were characterized by X-ray diffractometry and scanning electron microscopy, whereas the films'optical properties were studied by spectrophotometry, spectroscopic ellipsometry and classical single-oscillator model. Some physical parameters related to the film's optical properties were fitted in terms of single-oscillator model by using the measured spectroscopic ellipsometric parameters, based on which the relationship between the film's microstructure and optical properties was studied by constructing the general oscillator model. Some creative research results are listed as follows.1. Single-phased Ag2O film was successfully deposited by RF sputtering technique and lowered the critical thermal decomposition to about 200℃. This may deal with the bottleneck of the film's application in optical and magneto-optical storage.2. Using RF sputtering technique, single-phased Ag2O film with (111) preferential orientation was deposited at T=200℃, OFR=0.667 and P=200 W. With increasing the P from 120 to 240 W, the average grain size along (111) orientation increases from 22.92 to 27.96 nm and then decreases to 26.66 nm. The film's surface shows an evolution from even and compact to loose and porous structure.3. Using RF sputtering technique, a series of Ag2O films were deposited at OFR= 0.667 and P=200 W by modifying the T values. The Ag2O films deposited at the T below 200℃are (111) preferentially oriented. The crystallization tends to become poor with increasing the T values from 100 to 225℃. Especially, the Ag2O film deposited at T=225℃lost the (111) preferential orientation. Correspondingly, the film's surface morphology obviously evolves from the uniform and compact surface structure to the loose and gullied surface structure. With increasing the T values, the film's transmissivity and reflectivity in transparent region are gradually reduced, while the absorptivity gradually increases. The film's optical energy gap (Eg opt) largely decreases from 3.25 eV to 2.77 eV as the T increases.4. A series of silver oxide (AgxO) films were deposited on glass substrates at T 200℃and P=200 W by RF sputtering using different OFR values. The Ag2O film deposited at OFR=0.667 is best crystallized and (111) oriented. The average grain size along Ag2O (111) orientation increases from 23.65 nm to 28.41 nm with, while the film's conductivity with an order of -4 largely decreases with increasing the OFR. The film's transmissivity in near infrared region surpasses 70%, while sharply decreases in the visible region. The film's E g, dir changes in the range from 3.266 eV to 3.107 eV.5. Using the measured spectroscopic ellipsometry plus single-oscillator model, the film thickness, refractive index, extinctive coefficient, plasma oscillator frequency and energy gap of the single-phased Ag2O film is fitted using general oscillator model(include one Tauc-Lorentz oscillator and two Lorentz oscillators).. The result indicate that the normal optical dispersion occurs below 2.13 eV, and the abnormal optical dispersion occurs above 3.3 eV, which corresponds to the plasma oscillator frequency. The fitted E0 and Ed closely related to crystalline structure and ionicity are 3.546 eV and 13.367 eV, respectively, indicating that the cubic single-phased Ag2O film as-deposited by RF sputtering falls into the ionic class. The fitted optical engergy gap and plasma oscillation frequency in terms of single-oscillator model are 0.89 eV and 3.44 eV, respectively. |
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