由於小尺寸及高整合等優勢，微機電麥克風在近年來迅速發展；雖然在製程上可與半導體製程相容，但在沉積、蝕刻等製程後，結構中的殘餘應力會使其產生非預期之形變，進而影響產品的穩定性。過去幾十年來，關於微機電元件之研究已臻成熟，但以製程模擬方法來估算製程結果的研究卻相當少見。本研究將製程模擬技術應用於有限元素分析中，提出分析電容式微機電麥克風的殘餘應力與預變形之方法。
薄膜之殘餘應力可細分為本質應力及熱應力。本質應力為製程相關參數，須由實驗得知，以做為有限元素模型分析之初始條件。本研究首先針對麥克風模型進行多層薄膜應力量測實驗，並於各層薄膜沉積後進行熱循環退火，結果指出薄膜在高溫退火後，其殘餘應力減小且薄膜特性趨於穩定；由製程產生於氧化矽及多晶矽之本質應力，將由壓縮熱應力改變至張應力及接近無應力狀態；此外，金屬鋁薄膜經由退火可降低本質應力，且當應力值到達塑性區後，其應力變化不明顯，因此在模擬中只需考慮鋁薄膜之熱應力。然而當鋁薄膜在次微米等級之厚度時，其材料強度相異於較厚之鋁金屬，有必要於模擬分析中考慮隨厚度而變之鋁薄膜材料參數，此參數可由文獻及實驗比對得到，以此模擬方法可適當表現出實際鋁薄膜的力學行為。
微機電麥克風之殘餘應力分析結果顯示，多晶矽振膜在承受壓應力或低應力情況下，製程結束後會有彎曲變形產生，將會造成麥克風共振頻率與靈敏度偏離設計值；藉由控制薄膜沉積與退火溫度有助於改善此現象，使其在薄膜蝕刻後保持微小張應力且平坦無變形。

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