| The rapid development of communication technology advance the study of microwave materials and its device, and micromation device also become its trend. Microwave ceramic has high permittivity, high Qf, stable performance low cost, has been one of mainly microwave devices. However its development can not keep the track of micromation of other device.In view of microwave ceramic thin film has many good properties, such as easy integration and coupling, low loss, etc. It is obviously important to study dielectric properties and preparation of this thin film. However this field research hasn't been reported by now. In this paper, we prepare microwave ceramic thin film, and study its relation among its preparation, dielectric properties and phase structure. Then the feasibility is discussed about microwave device based on this film.The two classical materials is selected, which are MgTiO3-0.05CaTiO3 (MCT) with high Qf and BaO-Nd2O3-TiO3 (BNT) with high permittivity. This ceramic thin film is prepared by magnetic sputter. Its preparation about magnetic sputter is study in third part, we also analyze its relation among its preparation, dielectric properties and phase structure in this part. A new method about measurement complex permittivity of dielectric thin film(um) is present in second part. In four part, the thin film microstrip line based on this film is discussed by computer emulator. We get some results as follow:1. high quality MCT thin film is obtained. Thin film keeps its ingredient. The mainly phase, which is long strip, is the mixture of MgTiO3 and CaTiO3, and has uniformity size of crystal grain about 1.0-1.2um. There have also little impurity between crystal grain such as MgO, TiO2, and MgTi2O5. the film is compact, uniform and low stress. The thin film grows along oxygen hexagonal close-packed plane and has a shrunken unit cell. Its polarization electron cloud move form Ti to Mg and O. Its permittivity is 21.9, its Qf is about 18000~25000GHz, and has a little positivetemperature coefficient. MCT film grows from primal ball grain to big orient grain.2, high quality BNT thin film is obtained, which keeps its ingredient and has less impurity than bulk BNT. mainly phase of the thin film is BNT solid solution, which orients along c axis of oxygen octahedral, and lattice plane along c axis is lengthen, and crystal grain size is about 0.5#2.0um. there are some closed pores between mainly phase grains. Growth model is belonging to Volmer-weber mode. This thin film has same dielectric properties with bulk BNT.3. The experiment result show that underlay and its temperature, sputter air pressure and its proportioning have mainly influence upon the quality of MCT and BNT thin film, we get optimize processing parameters as follow. As to MCT: underlay is SiO2 orient along (110) and its temperature is above 610℃, sputter air pressure is about 0.25-0.3Pa, O:Ar=l:l, net input power is 300W, and its anneal is 550℃/30min. As to BNT: underlay is LiNbO3 orient along (111) and its temperature is above 550℃, sputter air pressure is about 0.25-0.25Pa, O:Ar=1.5:l, net input power is 250W, and its anneal is 500℃/30min.4. A new method based on multi-dielectric perturbation is present to measure dielectric thin film, which thickness is below urn. The experiment result show that the error of this method is below 7% and it's an accurate method. The compute equation is deduced through microwave theory in this paper. This method is realized by rectangle cavity resonator. Some improved measure is also present aimed at the factor of size (k) and the factor of frequency (Af and AQ).5. The thin film microstrip line based on microwave ceramic film is study by computer emulator. The high permittivity thin film can act as good dielectric layer, which could focus electromagnetism energy, decrease energy loss. Then highly increase integration, and decrease size of microstrip and coupling between microstrips. The appropriate structure of dielectric layer can gain good compositive properties.
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