Epitaxial transformation of hcp-fcc Ti sublattices during nitriding processes of evaporated-Ti thin films due to nitrogen-implantation

チタン蒸着膜の窒素イオン注入窒化過程におけるチタン副格子のhcp-fccエピタキシャル構造変化

Chen, Y.*; Feng, X.*; 粕壁 善隆*; 山本 春也; 吉川 正人; 藤野 豐*

Chen, Y.*; Feng, X.*; Kasukabe, Yoshitaka*; Yamamoto, Shunya; Yoshikawa, Masahito; Fujino, Yutaka*

本研究では、原子力機構のイオン導入型400kV電子顕微鏡を利用して、チタン蒸着膜への窒素イオン注入窒化過程におけるチタン副格子の六方最密-面心立方(hcp-fcc)構造変化を、透過型電子顕微鏡法及び電子エネルギー損失分光法によりその場観察・評価し、分子軌道計算による電子状態の評価と合わせて窒化チタン薄膜の形成機構及び配向の制御性に関する知見を得てきた。本発表では、窒素イオン注入によるチタン薄膜の窒化過程と電子構造から考察したhcp-fccエピタキシャル構造変態について報告する。

Epitaxial transformation processes of titanium films due to Nitrogen-implantation have been clarified through in-situ observations by using transmission electron microscope(TEM)and electron energy loss spectroscope, along with molecular orbital calculations. The N ions with 62 keV are implanted into as-deposited Ti films which consist of hcp-Ti and TiH with preferred orientations, in the 400 kV analytic high resolution TEM combined with ion accelerators at JAEA Takasaki. Thus, titanium nitride (TiN) films with preferred orientations are epitaxially formed by the inheritance of partial atomic arrangement of hcp-Ti or TiH in as-deposited Ti films and by the occupation of octahedral sites by N atoms, which elucidates that epitaxial transformation of hcp-fcc Ti sublattices occurs.