近幾年來，原子力顯微術(Atomic Force Microscope, AFM)對於在水中生物樣品成像的領域上扮演著越來越重要的地位。原子級解析度、快的掃描速率及不傷害樣品表面是對水中生物樣品成像的主要考量，而一新穎的懸臂樑激振量測方式：扭曲共振模式(Torsional Resonance mode,TR mode)正好具備以上這些條件，因此本研究旨在研究適合的懸臂樑設計並製作出此懸臂設計之掃描探針，能適用於TR mode在水中操作下，得到較高的共振頻率及較高的品質因子(Quality factor, Q)，以增加在水中成像的掃描速率與解析度；同時輔以較低之彈力常數，減少甚至避免在掃描過程中對於樣品表面的傷害。
本研究利用電腦輔助軟體(Computer-aided software, CAS)，包含有限元素分析軟體ANSYS Workbench、微機電專用分析軟體Intellisuite 及AutoCAD繪圖軟體，幫助本實驗對於懸臂樑尺寸、形狀、頻率、彈力常數做估算，並加以討論各種參數改變對於懸臂樑機械性質之變化，得到定性的分析結果。之後將符合需求之懸臂樑設計進行光罩繪製及製程結果模擬，找出最佳化製程參數，搭配微機電系統製程(Micro-Electro- Mechanical-Systems, MEMS)製作出多組不同設計之探針，加以實際測試在水中操作TR mode下之特性。同時在製程上，對於製作厚度較薄之懸臂樑良率不佳的情況做了大幅的改善，改進本實驗室原先製程所採用之Spar設計且改善蝕刻製程，能將蝕刻時間控制在±10分鐘，使得良率大幅上升，接近100%。
之後將實際製作之掃描探針成品，經由實際在水中操作TR mode測試，成功得到懸臂樑能在水中操作TR mode時具有良好的Q值(~60)、高共振頻率(~240kHz)及低彈力常數(~0.136N/m)。同時根據實際測試結果，對於何種懸臂樑能同時得到較高品質因子與較高之共振頻率，做定性之探討。

In recent years, Atomic Force Microscopy (AFM) plays an increasingly important role in characterizing living organisms in fluids. Atomic-level resolution, fast scanning rate, and non-destructive measurement are three highly desirable attributes for imaging living organisms in fluids. A novel driving method for cantilever: Tosional Resonance mode (TR mode) can just satisfy the aforementioned requirements. Therefore, the purpose of this study is fabricating scanning probes with suitable cantilevers designs used in TR mode in fluids (water) to get high resonance frequency, large Quality factor (Q)and low spring constant in order to increase the scanning rate, enhance the resolution, and prevent the surface of samples ,especially soft samples from hurting.
This study utilized computer-aided software (CAS), including ANSYS Workbench, Intellisuite, and AutoCAD to help estimating the dimensions, shapes, frequencies, and spring constants and discussed the influence of these parameters on the mechanical properties of cantilevers. After that, masks are designed for the cantilevers which meet the needs, finding the optimal parameters for processes by processes simulation, several cantilevers with different designs were manufactured by MEMS, and evaluating the characteristics of cantilevers used in TR mode in water. In addition, this study improved the previous spar design to solve the problem occurred when thin cantilevers are fabricated and improving the etching process, making the error of etching time within 10 minutes greatly increased the yields to 100%.
When operated in TR mode in water, we found good results: good Q value (~60), high resonance frequency (~240kHz) and low spring constant (~0.136N/m). A qualitative investigation about cantilevers with higher Q values was discussed as well.

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