| With the development of social economy and technology, people' demand for information has been being more and more, so the problem of large-capacity storage and high-speed transmission of information seems imminent. This will inevitably require that the devices, like electronic components and systems, should upgrade quickly, that is to say, the development should be toward to the direction for light, thin, short, small, low power, multi-function, high reliability, like the appearance of very large scale integrated circuit. This indicates that the metal thin film and multilayer materials will be applied more widely to microelectronic components. For instance, the Al-Cr thin-film material is used as a two-layer electrode structure in a-Si TFT and used to prepare extreme ultraviolet filter, and W-Al thin-film material is used as the Bragg reflection layer in thin-film bulk acoustic resonator (FBAR), interconnect components and diffusion barrier layer. And the micro-structure mechanical characteristics of film material are the primary index and basic performance of film quality, to some great extent, determining the reliability and life of films and devices. Therefore, the work of studying the interfacial structure mechanical properties of double-layer metal film is very necessary.In this paper, the double-layer thin film paired samples of Al-Cr, W-Al and W-Al were prepared by using the method of magnetron sputtering and the materials of Al and transition metals Cr, W. And the author investigated the mechanical properties of samples from the following aspects.1. Test mechanical properties of double-layer metal film material under the micro-scale. The author chose appropriate positions for indentation on the samples' surface of Al-Cr and W-Al, and tested multiple points with different depths by using nano-indentation instrument. As a result, the elastic modulus, hardness and the relationship curves with depth changes have been obtained.2. Establish finite element model and simulate. The loading and unloading processes of the indent contacting samples were simplified as axisymmetric model, the displacement function and calculation were conducted by using the software ANSYS. The load-displacement curves were obtained, and were compared with experimental data, but also the distributions of stress and strain in the W-Al model have been investigated.3. Apply thermal load. The High-low temperature test box was used to apply thermal load to sample W-Al and Al-W, with a range of -40-120℃, a cycle of 120 minutes and total five loading cycles. And the temperature at the most values retained constant for 15 minutes.4. Test interfacial bonding strength of samples. The Nano-Scratch Tester was used to respectively measure the interfacial bonding strength of the samples W-Al and Al-W that were conducted thermal cycling and without. And after comparing the two values, the result shows that thermal cycling load could enhance the interfacial strength. And the scratch traces of the samples were observed to prove the general process of interfacial structure damage.In summary, the paper uses the method of combining test with finite element simulation to analyze the mechanical properties of the double layer metal film samples. The analytical results can effectively promote the developments of the interface structural mechanics and physical mechanism research, and may also play a certain positive role on the interfacial structure optimization design of micro-electronic devices, engineering application and technology popularization.
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