| This thesis is made up of two parts. In the first part, the development up to date, the principle of superhard and supermodulus, as well as the modulation period characterization technique of nanoscale multilayer is described in detail. The properties of A1/A1N multilayers also were investigated. In the second part, the recent prograss of write-once light recording Cu3N films is introduced, especial to it's application fields. The properties of pure and Ti-doped Cu3N films were studied.Nanoscale multilayer film can be structured by deposited with several different materials by order in nanocale. In the study field of multilayer film, hard/hard structural multilayers have been attracting considerable attention, but these films are easy to break off because of big reduce stress. Considering the industrial applications, we designed soft/hard structural multilayer system, in which soft layer operate as cutting layer to release the inner stress. The improved soft/hard structural multilayer system could be applied for the field of mechanical manufacture, car industry and avigation etc.Nanometer scale A1/A1N multilayers have been prepared on Si substrates by DC magnetron sputtering technique with a columnar target at room temperature. And the tructural, mechanical and tribological properties of A1/A1N multilayers were investigated systemly:1) The optimal synthesization crafts of A1/A1N multilayers was obtained by a great deal of experimental attempt.2) There was great agreement in the modulation periods between designing and calculating. The intensity low XRD peak was decided by the number of modulation period. The A1/A1N multilayer with more periods had strong peaks. For multilayers of larger modulation period, the low XRD peak can be seen clearly.3) The single A1N film was hcp crustal structure with (100) preferred orientation;in multilayer, A1N phase showed a (002) preferred orientation. In multilayer, the position of (111) and (200) peaks of Al phase shifed with the modulation period. The intensityof A1N (002) peak increased with A1N layer thikness. As the modulation period increasing, the grain size became bigger close to value of the modulation period.4) The superhard enhancement can be seen for all multilayers to a certian extent. The thickness ratio A1/A1N had no significant influence on the hardness, and the increment of hardness was between 33% and 76%;the hardness of A1/A1N multilayer had a maximum of 24.5GPa for the modulation period of 16nm. This value was 2.9 times larger than the hardness calculated from the rule of mixtures and 1.9 times larger than the hardness of single A1N film.5) The A12.9/A1N1.1 multilayer had excellent wear and tear properties. All multilayers with this A1/A1N thickness ratio and different modulation period also had excellent tribological property.6) It can be known from XPS analysis that the A1N phase was more close to stoichiometric ratio, which resulted in the outstanding antioxidation, themal stability in vaccum and mechanical and tribological properties.Pure and Ti-doped copper nitride (CU3N) films were prepared by cylindrical magnetron sputtering on glass substrates. The influence of N2 flow rate, N2 partial pressure, sputtering power and substrate temperature on the structure, surface morphology, themal stability, electrical and optial properties of G13N films was investigated systernly:1) At different substrate temperature, the influence of N2 flow rate on the structure of CU3N films was different. As N2 flow rate increasing, the (100) preferred orientation of CU3N film deposited at room temperature was enhanced;the (100) preferred orientation of Cu3N film deposited at 100°C temperature was stable;the preferred orientation of Cu3N film deposited at 150°C temperature changed from (100) to (111).2) Ar gas can improve the deposition rate of CU3N film dramatically, the preferred orientation of Cu3N film deposited at 150°C temperature changed from (100) to (111) as the Ar rate increasing.3) The surface of as-prepared Cu3N film was uniform, smooth and compact. The surface roughness was very low. The surface grain size was influnced by substrate temperaturesignificantly, and the shape of surface particle was related with the preferred orientation of CU3N film. Additional Ar can make the morphology to more uniform and compact. The cross session of CU3N film showed a typical column structure. Above thickness of 800nm, the film surface became compact.4) As-prepared CU3N films were unstable in vaccum. The themal degenerate temperature of CU3N film deposited with pure N2 was 300°C, which was higher than that of CU3N film deposited with N2 partial pressure(250°C). The CU3N film deposited at room temperature had lowest themal degenerate temperature(200°C).5) The resistivity, lattice contant of as-prepared CU3N films and N2 flow rate had well direct proportion relation. Both resistivity and lattice contant of as-prepared CU3N films increased with N2 flow rate. And the resistivity of CU3N films can change from conductor to semiconductor. The critical lattice contant was between 3.807A and 3.824A.6) Ti-doping can improve the crystallinity of Cu3N films. The Ti-doped Cu3N film with clear preferred orientation had vivid column structure. The resistivity of Ti-doped CU3N film was larger three orders of magnitude than undoped Cu3N film. With Ti-doped content increasing, the absorption edge had a blue shift.
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