原子力顯微鏡探針在掃描過程中的磨耗，一直是一個常被忽視卻極為關鍵的現象。磨耗會降低掃描影像的解析度與減少探針的使用壽命；磨耗發生的原因在於探針與試片接觸時，兩者之間的交互作用力，可能致使探針磨耗亦可能傷害試片表面。在一般的環境下，試片表面上往往會有水膜的存在，水膜會使探針與試片接觸時產生毛細力（Meniscus force），增加探針與試片之間的拉力，致使探針或試片的磨耗變大。如何避免探針磨耗帶來的影響，便是本實驗的主要研究課題。
為了解決水膜帶來的問題，本實驗藉由改善探針表面的性質，在探針上浸鍍（Dip coat）一疏水性自組裝單分子層薄膜（Self-assembled monolayer，SAM），以降低毛細力的影響，減弱探針接觸到試片時的力道，減少磨耗的產生。DDMS（Dichlorodimethylsilane）、OTS（Octadecyltrichlorosilane）及FDTS（1H,1H,2H,2H-Perfluorodecyltrichlorosilane）為本實驗所選擇的三種具備疏水性的SAM塗層材料。先在矽晶圓上浸鍍SAM塗層，經水接觸角及XPS圖譜分析比較後，最佳化浸鍍的實驗參數；再將SAM塗層浸鍍到AFM探針上，與未塗層探針一起做輕敲式掃描（Tapping mode）的磨耗測試。
磨耗測試的結果分析，本實驗以SEM／TEM影像，做奈米尺度下，經表面改質的探針與未塗層探針在掃描前後的針型變化比較；並以計算掃描線的寬度變化方式，量化探針在掃描過程中的即時磨耗量。
本實驗提供了製備自組裝單分子層薄膜的方法，並製作了耐磨耗探針，延長探針的使用壽命。我們給予了AFM使用者，探針針尖在掃描前後的變化量比較，提昇使用者在解讀掃描影像時的正確率。在未來的研究中，可以採取不同的SAM薄膜製程，以達到更優良的薄膜性質；或者將浸鍍SAM薄膜的探針，應用在其他不同的掃描模式，例如：關鍵尺度模式（Critical dimension AFM，CD-AFM）、接觸模式（Contact mode）中做進一步的探討。

Wear of probe tips is a critical issue during the use of atomic force microscope (AFM) in metrology and surface characterizations. Wear can reduce the image resolution and introduce artifacts. The tip-sample interactions during AFM scanning result in adhesion and friction (also known as stiction) that, consequently, cause the increase of tip radius or damage of sample. In general environment, a water layer exists on sample surface, and causes meniscus force as AFM tip approaches sample. The thin water layer enhances attractive force, and increases the wear of tip or sample. How to prevent the tip wear during AFM operation is the major research in this study.
In order to reduce the meniscus force from water layer, we modified the property of probe surface with dip coating of a hydrophobic self-assembled monolayer (SAM) on AFM probe. DDMS, OTS and FDTS are the three hydrophobic SAM materials in this study. We coated the SAM on silicon wafer, and then measured water contact angle and analyzed the type of chemical bonding by XPS to find out the best parameter of dip coating.
In this study, a comprehensive investigation of wear of the uncoated/coated AFM tips in tapping mode scan was performed. We used SEM/TEM image to characterize probe tip shape and track the evolution of tip shape during wearing tests. Furthermore, we developed a method to quantify the in-situ wear by measuring the width of scanning line.
Finally, we provided a coating method of hydrophobic SAM and manufactured wear-resistance coating which extends the lifetime of an AFM probe. During scanning, we offered an in-situ wear quantification approach which improves the accuracy of AFM measurements. In the future investigation, we plan to utilize different process of SAM coating to obtain better surface property, and apply SAM coatings to different AFM modes such as Critical dimension AFM (CD-AFM,) and contact mode.

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