Deposition of Iron Nitride Films with Large Saturation Magnetization by Using a Sputtering Type Plasma Source.

为了获得具有较大饱和磁化强度的软磁薄膜，尝试使用溅射型等离子体源和对靶溅射系统沉积氮化铁薄膜。本研究由以下三个方案组成：(1)澄清薄膜沉积过程以控制沉积薄膜的微观结构；(2)改进对向靶溅射等离子体源；(3)沉积氮化铁薄膜并澄清沉积参数与薄膜结构的关系。在第一方案中，通过计算机模拟明确了控制沉积粒子在衬底上的入射角和沉积粒子能量的分布对于获得均匀致密结构的薄膜是重要的。在第二方案中，结果表明，对向靶溅射型等离子体源中提取的Fe离子在四重质谱仪上测量的Fe离子占总提取离子的比例在10%以下，但随着放电电流的增大，从开始发生自溅射的等离子体源中提取的Fe离子显著增加。研究还发现，在如此高的电流密度下，通过在直流高压上施加10 kHz的脉冲电压，可以显著提高等离子体源中溅射放电的稳定性。入射到衬底上的离子的数量和能量的增加抑制了薄膜中的微晶生长，从而改善了薄膜的软磁性能。薄膜中的微晶取向也随着离子在衬底上的入射而变化。在本研究中，没有得到含有Fe&lt；16&gt；N_2相的薄膜，也证实了没有大入射角粒子沉积的薄膜具有致密的结构。

In order to obtain a soft magnetic thin film with large saturation magnetization, deposition of iron nitride films by using a sputtering type plasma source and a facing target sputtering system has been attempted. This research was composed of following three projects(1)clarifying the film deposition process to control the micro structure of the deposited film, (2)improvement a facing target sputtering type plasma source, and(3)deposition of iron nitride films and clarifying the relationships between the deposition parameters and film structure.In the first project, it became clear that control of the distributions of incidence angle and energy of deposition particles on substrate are important to obtain a film with uniform and dense structure by computer simulation.In the second project, it was found that Fe ions extracted from the facing target sputtering type plasma source can be increased remarkably as the discharge current increases from a value where self sputtering begins to occur, although the Fe ion ratio to the amount of all extracted ions investigated with a quadruple mass spectrometer was below 10%. It was also found that stability of the discharge for sputtering in the plasma source at such high current density can be improved significantly by putting 10 kHz pulse voltage upon DC high voltage.In the third project, iron nitride films were deposited by using both the plasma source and a facing target sputtering system. An increase in the amount and energy of the ions incident on the substrate suppresses the crystallite growth in the films, which results in the improvement of the soft magnetic properties of the film. The crystallite orientation in the film also changes with the incidence of ions on the substrate. In this research, the film with Fe_<16>N_2 phase was not obtained.It was also confirmed that the film deposited without high incidence angle particles has a dense structure.