臺灣博碩士論文加值系統

本研究設計並製作具有倒鉤狀探針的乾式電極，以用於生理電訊號如腦電波之擷取。與傳統濕式電極相較，乾式電極的主要優點是不需導電凝膠之使用，所以不會因導電凝膠逐漸乾燥而使量測訊號品質隨著時間降低，較利於進行長時間量測。為了使本研究開發之探針狀電極可直接刺穿角質層以降低皮膚角質所造成的高阻抗，並避免電極刺及皮膚的真皮層造成使用者感受到疼痛不適，本研究探針之設計的電極探針長度設計於50~100μm之間，以符合人體角質層厚度約10~15μm，表皮層厚度約50~100μm的條件。由於是倒鉤的幾何形狀，電極刺入皮膚後，移除電極所需的力量會增加，可加強電極的附著能力及量測時的穩定性。電極之製作皆以濕蝕刻技術為主，其優點為製作方法簡單、設備需求及製程成本低。我們也利用蝕刻模擬軟體Etch3DTM進行蝕刻模擬，協助濕蝕刻製程之參數規劃。製作過程首先以添加異丙醇之氫氧化鉀蝕刻液製做出探針狀電極，探針平均長度為81μm。初步電極完成之後，則利用光阻旋轉塗佈與對位黃光微影技術，將蝕刻遮罩成功製作於電極之上。本研究使用之蝕刻遮罩材料為負光阻SU-8 2050，其材料優點為可抵抗化學蝕刻並能夠容易定義遮罩形狀。光阻保護遮罩有方形與蝕刻孔式兩種設計。完成後的方形遮罩，其邊長約150μm，高度約120μm。蝕刻孔式遮罩則為利用半徑65μm的半圓形孔洞做為蝕刻孔，其餘部分皆受光阻保護。遮罩完成後，將硝酸與氫氟酸混和做為等向性蝕刻溶液，進行探針倒鉤狀蝕刻成型。利用方形遮罩所完成的倒鉤探針電極，其長度85μm，寬度最寬處21μm，最窄處11μm；蝕刻孔式遮罩完成的探針，長度81μm，寬度最寬處20μm，最窄處12μm。

In this work, barbed dry electrodes are designed and fabricated by MEMS technology for biopotential measurement such as EEG.　Compared to the traditional wet electrodes, the dry electrodes do not need electrolytic gel to reduce the impedance between skin and electrodes, so dry electrodes are more suitable for long-term measurement. Our proposed dry electrodes consist of arrays of miniaturized spikes. These spikes are designed for penetrating human skin so that the high impedance problems associated with layers of the outer skin can be resolved. We design the electrodes 50-100μm in length to avoid the painful or uncomfortable feeling during the measurement. The fabrication of electrodes is based on wet etching, which is simple and low cost. The simulation software Etch3DTM is used to evaluate the fabrication parameters of the wet etching. The spikes are fabricated by KOH. Subsequently, the photoresist is patterned as the etching mask on the spikes, and then etched in the solution mixed with HNO3 and HF. The fabricated barbed electrodes are 81μm in length, and widest and narrowest width is 20μm and 12μm, respectively.

致謝 I
摘要 III
Abstract IV
目錄 V
圖目錄 VII
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 1
1.2.1 腦電波電極 1
1.2.2 乾式電極製程方法 6
1.3 研究動機與目的 18
1.4 論文架構 19
第二章 理論與設計 20
2.1 濕蝕刻原理 20
2.1.1 等向性濕蝕刻 21
2.1.2 非等向性蝕刻 22
2.2 電極設計規劃與限制 24
2.3 電極蝕刻模擬 26
2.3.1 Etch3DTM軟體簡介 26
2.3.2 蝕刻模擬 27
第三章 製程方法與步驟 30
3.1 製作流程規劃 30
3.2 製程技術與原理 32
3.2.1 光罩設計與製作 32
3.2.2 晶格方向對準 33
3.2.3 晶圓清洗 35
3.2.4 微影製程 36
3.2.5 反應離子蝕刻 41
3.2.6 晶圓切割 42
3.2.7 非等向性濕蝕刻 43
3.2.8 等向性濕蝕刻 43
第四章 實驗結果與討論 44
4.1 製作結果 44
4.2 蝕刻時間與倒鉤電極成形探討 47
4.3 倒鉤電極蝕刻方法改良 52
4.4 模擬與蝕刻差異討論 58
第五章 結論與未來展望 61
5.1 結論 61
5.2 未來展望 62
參考文獻 64
附錄A 70
附錄B 76

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