LSI用サブミクロン薄膜のモード別界面端はく離発生条件

概要

論文の詳細を見る
The interface fracture between sub-micron films can be classified into two types: opening mode and sliding mode. Corresponding to fracture mode, the interface strength should be evaluated quantitatively, but it is difficult to apply mode-controlled load. In this study, the criteria of crack initiation at the edge of interface between thin films for an LSI are examined under opening mode and sliding mode, respectively. Not only the evaluation method for opening mode but also that for sliding mode is proposed. The Si_3N_4/Cu/TaN films on a Si substrate is tested. The crack initiates at the Si_3N_4 (thickness: 100 nm)/Cu (thickness: 400 nm) interface in both modes. Stress analysis reveals that singularity fields of σ_<xy> and τ_<xy> appear near the edge in opening mode and sliding mode, respectively. On the basis of fracture mechanics concept, the interface fracture toughness of both modes are evaluated. The fracture toughness of sliding mode is smaller than that of opening mode and it is a characteristic of the interface strength between thin films.多層サブミクロン薄膜を対象としたせん断モード破壊試験方法を開発するとともに，窒化シリコンと銅薄膜界面におけるモード別の界面強度の差について定量的に検討した．
2003-09-25