隨著科技進展，各種存儲以及感測元件逐步朝向高密度小尺寸的方向發展，並且隨著尺寸的縮小，量子效應逐漸顯著。自旋極化掃描穿隧電子顯微鏡藉由磁性探針，除了提供原子級別的實空間顯像技術，更能用於同尺度下的磁區顯影，以及自旋極化掃描穿隧能譜的量測，這些特性對於了解表面自旋結構有極大的幫助。而這些量測的可靠性都仰賴於探針的穩定性。本論文研究工作是建立反鐵磁性的鉻針製備流程，以及對奈米鐵島在銅基板的量測。
論文的第一部分，改進電化學蝕刻鉻針流程。過往方式都採以直流電的"Drop-off"方法來製備出尖銳的針頭，然而除了需要將探針從塑料套中取出的繁瑣流程，由於材料特性易在尖端形成斷面。為了提高良率以及簡化流程，改成採用交流的Drop-off的方式，除了能夠避免形成須從塑料套取出的過程，也能減少斷面形式的針尖。
第二部分藉由分子束磊晶在銅基板鍍上鐵，並利用機械接觸的方式產生自旋極化探針，觀察奈米鐵島嶼的表面結構以及磁區顯影。除了過去已被觀查到在bcc-like 奈米鐵島嶼上的自旋螺旋結構，同時還發現了原本反鐵磁性的fcc鐵島嶼，在吸附氫氣下表面同樣會產生條紋狀的磁性訊號。

Spin-polarized scanning tunneling microscopy(SP-STM) is powerful technique to directly observe real-space spin structure at atomic-scale and measure spectroscopy(SP-STS). The performance depends on magnetic-tip. In this thesis, we develop an improved electrochemical etching method, and have measured the nano Fe islands on Cu(111).
In the first part of the thesis, we introduce the improvement of production method of Cr tips. To prepare sharp tips, we apply the drop-off method of electrochemical etching of Cr tips, and this method usually uses Direct Current(DC). However, if we choose DC power as power supplier, it will complicate the procedure during taking the probe out of the plastic sleev, and furthermore, it will result in brittle fracture at tip. To simplify the production method and to avoid the defective tips, we choose AC power as power supplier instead.
In the second part, we use spin-polarized tip generated by mechanics contact to observe the surface structure of Fe island on Cu(111) and as result, we find magnetic spin structure on hydrogen adsorption fcc-phase island.

第一章簡介............................................... 4
第二章掃描穿隧電子顯微鏡(STM) ............................ 28
第三章探針製備........................................... 45
第四章實驗儀器及操作...................................... 58
第五章實驗結果與討論...................................... 75
第六章結論............................................... 99
Reference ...............................................100
Appendix ................................................107

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