過去IBS(Ion Beam Sputtering)的研究放在入射角度、離子束能量與離子通量對於圖案的影響，對於濺鍍過程中可能出現的金屬雜質的影響不是很重視。最近幾年，由於同步沉積，濺鍍的金屬在基板上奈米圖案的形成被評估為關鍵作用，因而引起了許多研究者的興趣。IBS的優點是可以將以往蒸鍍無法達成的高熔點金屬濺鍍在基板上進行研究。而將鉭以IBS方式濺鍍在矽(111)表面就是這次研究的主題。
本實驗的IBS條件為：用 2 keV的氬離子以30∘角入射緊鄰在矽(111)基板表面且與其垂直的鉭片，矽(111)基板溫度為室溫和1000 K。我們選擇在矽 (111)表面上距離鉭片0.9 mm、1.2 mm、1.5 mm、1.8 mm、2.1 mm的位置上以STM觀察測表面情形，以探討矽(111)表面在濺鍍並加熱後的變化，主要目的是統計2D islands與3D island的高度與面積大小的分布。在加熱到1293 K時，我們探測2D islands至少有兩種屬於金屬性質的結構，有domian的為√3×√3，另一為無domain的蜂巢狀結構，其原子間距為0.31 nm，目前是未知結構。在矽基板為1000 K的實驗中，發現一種半導體性質的2D island，經由STM影像計算原子間距，推斷其為√7×√7結構，而3D island 有不可逆性，會隨著加熱而聚集。根據矽跟鉭的相圖，3D island應為TaSi2結構。
本實驗統計了鉭在矽(111)形成之表面結構與鉭片距離、基板溫度的關係，發現了2D island 有3種結構，而3D island推論為TaSi2結構，若能有理論方面的結果，相信更能判斷出2D island鉭矽化物的結構。

In the past, the research of ion beam sputtering (IBS) emphasized on how the incidence angle, ion energy and the flux of ion beam change the patterns formed on the sputtered substrates. The influence of metal impurities produced in the IBS process was usually ignored. In recent years, due to the metal co-deposition, the metal impurities has been evaluated as a key role in the formation of nano-patterns on the substrate surfaces. Therefore, it attracted the interest of many researchers. IBS has the advantage to carry out the deposition of metals of high-melting points which cannot be achieved easily by thermal evaporation in the past. In this research co-deposition of tantalum by IBS on the Si(111) surface to form tantalum silicides is our subject.
The IBS conditions in our experiments are: a 2-keV Ar+ ion beam strikes the Si(111) surface at an incidence angle 30o to the surface normal. A tantalum sheet is positioned perpendicularly to the Si(111) substrate. When ISB is performed, both Ta sheet and Si(111) substrate are sputtered. The temperature of Si(111) substrate is kept at room temperature and 1000 K when IBS is carrying out. We observe the sputtered surface with STM at the distances of 0.9 mm, 1.2 mm, 1.5 mm, 1.8 mm and 2.1 mm from Ta sheet after sputtering followed by a post-annealing. Our goal is to investigate the structures and distributions of all possible surface features formed in the sputtering-annealing process. After post-annealing at 1293 K, we found two structures for 2D islands, both have metallic ehavior under STM imaging.The first one is √3×√3 structure with domains distributed on island surface.The second one is a honeycomb structure with interatomic separation 0.31 nm and covers the entire island surface without domain. So far we do not know its structure.In the experiment of IBS on hot Si(111) substrate at 1000 K, we found a semiconductor-like 2D island which has a √7×√7 structure.The 3D islands grow bigger irreversibly upon annealing. According to Si-Ta phase diagrams, the structure of 3D islands should be TaSi2.
In our experiment, we try to find out the changes of 2D and 3D islands formed after the co-deposition of Ta on the Si(111) surface at different positions and Si substrate temperatures. We found three structures for 2D island and we conclude that the structure of 3D island is TaSi2. However, our conclusions of the structures for 2D islands are short of the reconfirmation of theoretical work. With the theoretical results, the structures of 2D islands can be determined correctly.

第一章 導論 14
1.1研究動機 14
1.2 矽晶體 15
1.3相關文獻 18
1.3.1 在矽(111)面上的鉭矽化物的殼層光電子能譜和在STM上的表面特徵 18
1.3.2 以STM研究在矽(111)7×7的釩的nanocluster 21
第二章 儀器工作原理 22
2.1 真空系統與實驗儀器 22
2.1.1真空系統 22
2.1.2真空幫浦及氣壓測量儀介紹 23
2.1.2抽真空概略程序 26
2.2 掃描穿隧顯微鏡 28
2.2.1 量子穿隧效應 28
第三章 儀器介紹與實驗步驟與過程 30
3.1 實驗環境 31
3.2 儀器介紹 34
3.2.1 Omicron VT-STM 34
3.2.2 Specs ion gun 35
3.3 樣品處理 37
3.4 STM探針製作 38
3.5 實驗步驟與過程 39
第四章 結果與討論 41
4.1 2 keV的能量以30∘Sputtering鉭在矽(111)的表面結構 41
4.1.1位置一:距離Ta板0.9 mm 41
4.1.2 位置二:距離Ta板1.2 mm 45
4.1.3 位置三:距離Ta板1.5 mm 46
4.1.4位置四:距離Ta板1.8 mm 47
4.1.5 位置五:距離Ta板2.1 mm 50
4.1.6 第一次加熱 圖案形成與Ta板距離間的關係討論 53
4.2 加熱後表面圖案的變化 57
4.2.1第二次加熱 以1083 K的溫度退火5分鐘 57
4.2.2第三次加熱 以1153 K溫度退火5分鐘 60
4.2.3第四次加熱 以1183 K溫度退火5分鐘 63
4.2.4第五次加熱 以1243 K溫度退火5分鐘 67
4.2.5第六次加熱 以1243 K溫度退火10分鐘 70
4.2.6第七次加熱 以1293 K溫度退火5分鐘 75
4.2.7 2D islands在加熱下的變化與其上面的結構 81
4.3 第二次濺鍍 84
4.3.1 動機 84
4.3.2 位置一:距離 Ta板0.9 mm 85
4.3.3位置二:距離Ta板1.2 mm 88
4.3.4位置三:距離Ta板 1.5mm 89
4.3.5 位置四:距離Ta板1.8 mm 91
4.3.6位置五:距離 Ta板2.1 mm 95
4.3.7 兩次濺鍍後的圖案差異探討 97
第五章 結論 101
六 參考文獻 102

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