在現代積體電路晶圓製造生產線上，製程設備的穩定性與製程良率乃是製造現場最重要的課題，電漿製程設備又是其中最具挑戰性者。本研究以製造動態隨機存取記憶體(DRAM)之200mm晶圓生產線上磁場輔助活性離子蝕刻設備作為研究對象，以射頻阻抗計所收集之資訊, 觀察到電漿射頻參數隨著設備運轉時數及保養狀態呈現週期性之變化, 並且與電漿腔體內壁聚合物沉積及聚集環之消耗有顯著的關聯性。我們設計一系列實驗來驗證這個觀點, 將腔壁聚合物沉積與聚集環消耗這二項影響因子分離, 估計其對各項電漿射頻參數之影響程度。在一個腔體保養週期中, 腔壁聚合物厚度之增加與聚集環厚度之減少均為線性, 但其對射頻參數之貢獻包含線性與非線性。電漿腔體之運轉狀態, 如待機, 抽高真空, 或進行腔壁聚合物調節(seasoning), 會影響某些電漿射頻參數, 同時也會對蝕刻率造成暫態之影響。SiF2與F之電漿光譜相對強度及變化幅度會隨著腔體運轉時數而改變, 意味著腔壁聚合物之表面狀態也逐漸改變。透過對傳輸線與寄生阻抗之估計所得到之傳輸矩陣, 將量測到的電漿射頻參數還原至腔體內部電極板表面之狀態, 並以電漿相關理論去解釋這些現象。同時也嚐試運用電漿鞘層等效電路模型來驗證鞘層結構之適用性, 並建構一指標, 為腔體狀態與電漿射頻參數取得聯繫。期望未來能以此基礎, 充分運用射頻阻抗計所收集之資訊, 更深入瞭解電漿腔體之健康狀態, 以及其背後之物理機制。建構預測模型, 在製造實務上, 為設備在診斷管理及效率提升上提供參考資訊。

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