| The metal of W and Ti are widely paid attention to because its has high wear resistance, high hardness, excellent corrosion resistance and low coefficient of thermal expansion, etc. and two of the composite and the overall performance has been greatly improved, And the two metals composite has a greater improvement in the overall performance. Due to the high melting point of W and Ti (two W the melting point of 3400 DEG C, Ti melting point of 1668 DEG C), so the conventional process is difficult to prepare a mixture of homogeneous alloy material. With the development of micro electronic semiconductor, aerospace and automotive industry, many unique properties of metal based thin film materials have been widely used. W-Ti thin films have been widely attention due to their good thermal stability, low resistivity, excellent corrosion resistance, oxidation resistance and chemical stability, and Strong adhesion with the metal contact layer and SiO2 or Si substrate.In this paper, we use the magnetron sputtering technology and through the method of orthogonal test to determine the sputtering process of pure W, Ti and W-Ti thin films. Then preparing the W, the Ti and the W-Ti thin films with the content of Ti of 9at.%,17at.%, 27at.%,35at.%. Experiments using the modern testing technology such as XRD, SEM, EDX, TEM and AFM to characterize the structure and morphology of the films, and using the four probe tester, Nano Indenter, materials multifunctional surface analyzer and electrochemical workstation to test and analysis the electrical, mechanical, and corrosion resistance of the films. Finally, the failure mechanism of Cu/W-Ti/Si structure with different Ti content was studied by thermal annealing at different temperatures. The test results show that the variation of Ti content will affect on structure and properties of W-Ti thin films. XRD analysis showed that the W-Ti thin films showed the body centered cubic structure, when the Ti content in the films was 9-17at.%, the film only two characteristic diffraction peaks, corresponding to the BCC solid solution W100-xTix (110) and (211). When the content of Ti in the film is higher (about 27-35at.%), and appear weak HCP Ti peaks of (100). With the increase of Ti content, compared with the pure W films, body centered cubic structure of W-Ti thin films (211) crystal plane diffraction peaks was becaming weakening, (110) crystal plane diffraction peaks of hastens film is mainly presented (110) preferred orientation. The SEM and AFM tests show that the average particle size and the surface finish of W-Ti thin films change with the increase of Ti content. TEM analysis shows that W-Ti thin films were Ultrafine polycrystalline structure.Film properties testing show that the resistivity of the W-Ti thin films increases with the increase of Ti content, the hardness and elastic modulus of the films increase with the increase of Ti content at first and then decrease, when the Ti content is 9at.%the hardness and elastic modulus reach highest respectively is 25.1Gpa and 273.1Gpa. The friction coefficient of W-Ti thin film and the film base binding capacity increased with the increase of Ti content, the maximum was 0.215 and 22N, respectively. The addition of Ti greatly increases the defect density of W-Ti thin films, thus reduces the corrosion resistance of the films. When the Ti content is 35at.%, the corrosion current density is 0.0103mA/cm2, which is ten times higher than that of the Ti content of 9at.%.The failure temperature of Cu/W-Ti/Si structure decreases with the increase of Ti content, which indicates that the Ti addition reduces the blocking property of W-Ti. This is because the addition of Ti increases the defect density of the film itself, so that the phenomenon of Cu and Si layer is more easy to occur. And the self diffusion activation energy of W is much larger than the self diffusion activation energy of Ti, and the addition of Ti decreases the overall stability of the film.
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