自我組裝 (self-assembly) 合金原子團簇 (nanocluster) 的磁性、成長模式一直是被關注的焦點。本實驗主要研究鐵銀合金原子團簇在 θ-氧化鋁表面的成長行為: 先以高溫曝 100 L 氧氣的方式在鎳鋁合金(001)表面成長 θ-氧化鋁薄膜，再以兩支分別裝有鐵、銀渡源的電子束蒸鍍鎗 (Electron-beam evaporator) 同時在氧化鋁表面成長合金原子團簇，最後以掃描穿隧顯微儀(Scanning Tunneling Microscopy)觀測不同鐵、銀比例的合金原子團簇，以統計方式分析趨勢。結果發現，隨著銀的比例升高，高度與直徑的分部皆有上升的趨勢，但是直徑的上升率明顯大於高度。

The magnetic properties and growth mode of self-assembly alloy nonoclusters
were interests to surface science. Our experiment focused on the growth behavior
of Fe-Ag alloy nanoclusters on the ordered alumina templates. We carried out
the experiment by scanning tuneling miscoscopy (STM) under an ultra high vacuum
chamber with base pressure better than 5 x 10E-11 torr. The clean NiAl(001)
surface was prepared by repeating argon sputtr and annealing. Subsequently, it
was deposited 1000 L oxygen at elevated temperature to form the ordered alumina
templates. Iron and silver nanoclusters were deposited simultaneously on
Al2O3/NiAl(001) surface by electron-beam evaporators. We observed the alloy
nanoclusters by STM at low temperature. By increasing the silver composition,
the height and diameter of alloy nanoclusters was increase, but the increasing
ratio of diameter is higher than that of height.

1 簡介. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
2 氧化物性質. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
2.1 氧化鋁結構. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
2.2 金屬薄膜在氧化物上. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.2.1 薄膜成長模式. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.2.2 電子結構. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.2.3 吸附行為(adsorption behavior) . . . . . . . . . . . . . . . . . . . . . . . . . . .11
3 實驗流程與儀器原理. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
3.1 實驗環境－超高真空系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
3.1.1 氣體脫附. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
3.1.2 烘烤與去氣(Degas) 過程. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
3.1.3 真空幫浦. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
3.1.4 真空計. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
3.2 清潔表面－ (Flash)以及高溫退火(Annealing) . . . . . . . . . . . . . . . . . . .20
3.3 高溫曝氧. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
3.4 蒸鍍原子－電子束蒸鍍鎗(Electron Beam Evaporator) . . . . . . . . . . . . .22
3.5 表面量測－掃描穿隧顯微術(Scanning Tunneling Microscopy) . . . 22
3.5.1 電子穿隧效應原理. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
3.5.2 探針. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
3.5.3 掃描頭. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
3.5.4 成像原理. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
4 實驗結果討論與分析. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
4.1 處理基底樣品. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
4.1.1 清潔鎳鋁合金(001)表面. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
4.1.2 成長 θ-氧化鋁薄膜. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
4.2 估計鍍膜速率. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
4.3 成長金屬原子團簇於氧化鋁薄膜. . . . . . . . . . . . . . . . . . . . . . . . . . . .32
4.4 單一元素系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
4.4.1 在氧化鋁表面. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
4.4.2 在不同基底樣品(substrate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
4.5 合金系統. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
5 結論. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
文獻. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

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