纳米晶LaNiAl薄膜充氦技术研究

采用离子束辅助磁控溅射方法沉积出了纳米晶LaNiAl膜和纳米晶渗氦LaNiAl膜（膜厚约10 m），通过调节Ar-He气氛的比例可控制纳米晶膜中的含氦量（He/LaNiAl的原子分数5.7%~13.8%），通过该方法引入到LaNiAl金属薄膜中的氦量远高于采用球磨法制备的纳米LaNiAl粉中的含氦量。研究结果表明：渗氦LaNiAl膜中的氦含量（原子分数）可达13.9%，氦在膜的深度方向分布均匀；热解析分析恒温条件下沉积的渗氦膜的起始释放温度为848 K，最高释放温度为1407 K，主释放峰为1080 K，初步确定了氦主要是以团簇的形式存在于在纳米晶膜中。

Nano-crystal LaNiAl film with helium charged

Nano-crystalline LaNiAl film charged with helium atoms is prepared by magnetron co-sputtering. Low energy helium-4 atoms implantation is carried out by magnetron co-sputtering technique with Ar/He mixture gases around during the film growth. During the sputtering process, the ionized He atoms bombarding the cathode target are backscattered and implanted into the growing film. The film is CaCu5-type structure analyzed by XRD. Helium concentration is measured by proton backscattering spectroscopy (PBS), the most atom fraction of helium is 12.2%. Deduced by thermal desorption experiments and TEM, helium exists as He-V cluster in the nano-crystal films. Compared with 3He in a tritide, the implanted He in metal film is still quite different, but it is a good way to study how helium atom exists in La-Ni-Al inter-metallic compound.