在微光機電系統技術中，製作高深寬比結構為其一大特色，其中以蝕刻技術最為被廣泛使用。非等向性濕式蝕刻設備雖較為廉價且易取得，但其對單晶矽之蝕刻形貌會受晶格方向影響，而屬於乾式蝕刻之感應耦合電漿離子蝕刻(ICP-RIE)技術，雖然有極佳的高深寬比矽微加工能力，但此系統的價格相當昂貴(約1200~2000 萬/台)且加工成本極高，一般學術單位取得不易。
根據上述，本研究將發展低成本之電化學蝕刻(ECE)技術，應用於具高深寬比矽微結構之製作，以取代高成本感應耦合電漿離子蝕刻(ICP-RIE)在微機電技術領域之運用。由實驗結果顯示，本研究已順利自行開發電化學蝕刻高深寬比孔洞所需之設備，並利用此設備得到最佳之製程參數，蝕刻所得結構之深寬比超過40 以上，除此之外，並在蝕刻液中添加自行開發之添加劑，使孔洞側壁結構具更佳之粗糙度，其有非常顯著的效果。最後透過製程參數的調變，達到結構側向蝕刻以製作懸浮結構之目的，進而應用於靜電式微致動器之製作。

關鍵詞：微光機電系統、感應耦合電漿離子蝕刻、電化學蝕刻、靜電式微致動器

Etching process is one of the key technologies for fabricating high aspect structures in Micro Electro Mechanical System (MEMS). Equipment of anisotropic wet etching is lower cost than other etching technologies but the appearance of the etching result controlled by crystal direction for silicon wafer. Though inductively coupled plasma reactive ion etching (ICP-RIE) process can get extremely great high aspect silicon strictures but it’s very high cost process.
The project will develop the technology of low-cost electrochemical etching (ECE) for the fabrication of silicon micro- structure with high aspect ratio. The technique will take the place of ICP-RIE process. The results show we have set up photo-assisted electro- chemical etching apparatus in this study. we also find optimal process conditions with the apparatus and fabrication micro-structure with aspect ratio over 40. Moreover, a novel additive has been used to improve the structure roughness and its effect is very significant. The side etching will be occurred by adjusting process parameters and the free-standing beams can be achieved with only one mask. Finally, the micro-electrostatic actuator can be getting.

Key word: Micro Electro Mechanical System (MEMS), Inductively coupled plasma reactive ion etching (ICP-RIE), Electrochemical etching (ECE), Micro-electrostatic actuator

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