Ultrafast Dynamics Research Of Biochip Substrate Material Silicon Nanofilm

As the emerging of biochip technology, a lot of complex work of life science, such as data acquisition, data processing and analysis, could become integrated, miniaturized, and continuous. A key link of biochip production is selection and reasonable use of chip substrate. Based on the characteristics of the biological chip itself, we should have a more thorough understanding about the ultrafast physical process in extremely small scale of the materials we used.In this article, we mainly study the ultrafast dynamics property of a kind of biochip substrate material, which is silicon nano thin film. To make contrast and matting for the research of ultrafast dynamics in silicon nano thin film, we also take the research of that in copper thin nanofilm. The main research content includes:(1) Preparing the copper nano thin film and silicon nanofilm with magnetron sputtering method.(2) Using the femtosecond laser transient reflectivity technique to measure the transient reflectivity regular of copper thin film and silicon thin film, we got the data in different laser pulse energy. We analyze the ultrafast carriers transport process and ultrafast thermal transport process.(3) By quantitatively calculating the excited carriers, we analyze the contribution of silicon thin film carriers transport process to reflectivity change. We build the diffusion model to simulate the decay process of silicon thin film carriers density. The results of model calculating show the surface recombination velocity is S= 4×105cm/s, and the recombination time in bulk is shorter when the pump pulse energy become stranger.(4) Using the two-temperature model to simulate the ultrafast dynamics of copper film, we calculate she electron-phonon coupling coefficient is G=1.2×1016 W/m3K. We also build the two-temperature model for dealing with semiconductor ultrafast carriers transport process and ultrafast thermal transport process.