在微電機封裝中利用鋁鍺薄膜共晶接合可達到好的接合強度和良好氣密性特性，共晶鋁鍺薄膜大多以雙層膜結構方式接合，但此雙層膜結構需藉由時間擴散達到均質共晶組成。本研究利用濺鍍機以共濺鍍的方式製備鋁鍺薄膜，其組成約為72.8 at.%的鋁及約為27.2 at.%的鍺，希望能藉由共濺鍍直接形成均質鋁鍺薄膜以達到良好的接合行為，本研究分析不同接合溫度、時間和壓力等參數影響共濺鍍鋁鍺薄膜的接合特性。
由結果可發現在低於熔點的接合溫度之接合特性與富鋁相的生成有極大關聯，尤其接合溫度劇烈影響富鋁相形貌，當接合溫度在400 oC、接合壓力0.3 MPa和接合時間30 min時可有最佳的接合剪切強度，原因可能為微結構出現由富鋁相形成之網狀結構而增強機械性質，而當接合溫度提升至500 oC後，卻因生成大面積的富鍺相而降低接合剪切強度。

In MEMS packaging, aluminum-germanium eutectic bonding can achieve excellent bonding strength and good hermetic performance. Under many circumstances, using bi-layer aluminum/germanium thin film is the most common bonding approach, however it requires time and temperature to diffuse and to reach the homogeneous eutectic composition. This study used sputter technique to co-sputter aluminum-germanium thin film with the composition 72.8 at.% Al and 27.2 at.% Ge. This thesis investigated and analyzed the effect on the compositional variation and bonding strength under different parameters, such as bonding temperature, bonding pressure and bonding time.
The results showed that the formation of the Al-rich region and its occupying areas could greatly influence the bonding characteristics when the bonding condition was below eutectic temperature. Furthermore, under a bonding temperature of 400 oC, bonding pressure of 0.3 MPa and bonding time of 30 min the film exhibited the optimal shear strength due to the formation of network structure of aluminum rich regions that could enhance the mechanical properties. The bonding strength would be weakened by the formation of large area of Ge rich phase when raising the bonding temperature to 500 oC.

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