微機電結構所使用的材料絕大部分為脆性材料，其材料測試強度與裂縫分佈有關是隨機變化的，針對此設計環境本文建立適合微機電結構設計的設計流程與輔助分析程式，並針對微機電使用的材料測試強度不一致的問題，以結構破壞機率為基礎提出測試強度資訊整合的方法解決此問題，並提出微機電的材料測試強度資料庫格式的構想，依此構想建立之材料測試強度資料庫應可徹底的解決微機電材料測試強度混亂的問題，並經驗證整合方法的正確性。本文亦推導出結構破壞機率之等效安全係數與傳統安全係數的關係式，經驗證發現在結構在小變形的狀態下，此關係式極為準確。另外以自行發展的輔助程式分析晶圓沉積薄膜的破壞機率，並與破壞力學結果互相比較，發現兩個分析方法有極高的吻合度。而本文所提出的分析流程、發展的輔助程式、及推導的關係式，無論在機率分析、結構破壞機率展示、機率法與安全係數法的比較與連結、或成本最佳化設計等方面上，皆有良好之成果。本文期望在未來能設計實驗作為本文提出的分析流程、發展的輔助程式、及推導的關係式的實質之驗證，並與本實驗室發展的其他微機電設計程式整合，發展出完整的微機電設計輔助軟體，加以推廣供微機電設計者使用，以落實本文提出之微機電結構設計方法。

Due to the effect of length scale and process dependent flaw distribution, materials for MEMS applications usually exhibit different strengths from their bulk reference state and must be properly characterized. However, most MEMS materials are brittle and their fracture strengths vary with specimen sizes, loading types, and applied loads. In addition, the geometry and applied loads between testing specimens and structures for design are usually different and the characterized strength cannot be directly applied for MEMS design without modification. The scattering and inconsistency of testing strength of brittle MEMS materials imposes a critical obstacle for structural reliability assessment of MEMS devices. In this thesis, the nature of such a discrepancy and the effort to solve this issue are discussed and a rational structural design flow for brittle MEMS devices has been established. A method based on equal failure probability is also proposed to map the material strength obtained from test specimens to the equivalent strength for MEMS structural design. This conversion can be classified into three types to deal with difference in size, geometry, and applied loadings manner and the possible approach to form a material strength database for brittle MEMS material is suggested. The weakest link theory and Weibull statistics are adapted for illustrating the proposed data reduction process. Several examples are provided to illustrate the possible applications of this work. Finally, an equivalent safety factor concept is proposed to promote probabilistic structural design and the perspective to achieve a MEMS material strength database is discussed.

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