Calculation and verification of linear target deposition distribution

With the tremendous development of synchrotron radiation source in recent years, large-size X-ray mirrors are demanded. The linear magnetron sputtering target is suitable for preparation of these mirrors. Uniformity and roughness are important determinants of the mirror reflectivity. However, the uniformity of large mirror is difficult to control for the uniform sputtering area of the target is always limited. In addition, for the shape and large size of linear target, a lot of sputtering particles are deposited on the substrate with large incident angles which could lead to an increased roughness of the film. In order to solve these problems, it is necessary to have a comprehensive understanding of the sputtering and deposition rules of particles. By summarized many theories about particle sputtering and deposition and combined them with the equipment in our laboratory, a theoretical model was established to calculate the deposition distribution of particles.Two sets of experiments with target-to-substrate distances of 8cm and 10cm were carried out to verify that our model can simulate the deposition distribution of particles accurately through measuring all the silicon substrates pasted on the sample holder. Good results were obtained in both experiments which shows that our model can correctly calculate the distribution of particles.