本研究分為兩部份，第一部份為利用電遷移效應(electromigration)中的電子風力(electron wind force)特性，達到操控銀奈米線結構特定區域的凝聚，藉由研究結果提出一個新穎的唯讀非揮發型記憶體元件設計，並進一步將樣品置於高溫環境中量測，探討環境溫度對銀原子電遷移效應的影響。
樣品製作是利用電子束曝寫系統製作奈米線結構，接著使用電子束蒸鍍系統製作銀奈米線。測量的部分，則是對元件通電流並使用光學顯微鏡觀察結構變化，最後對樣品進行電壓-電流量測，並進一步改變環境溫度探討電子風力對銀原子所造成的影響。
我們發現可藉由控制電子流的方向，利用電子風力與銀原子間的交互作用，達到銀奈米線特定區域高溫凝聚之操控，且雖然樣品截面積較大的區域電流密度較小，仍能因電子風以及被沖刷原子的動量使之產生電遷移效應。並且透過加溫量測，得知環境溫度升高時，將會增強電子與銀原子間的動量轉移效應。
第二部份則著重於薄膜加溫，其在高溫環境下，因為要降低表面能，所以會從基板表面去溼（dewetting）並凝聚成顆粒，我們使用少有人研究的結構：雙層薄膜。我們探討矽基板上雙層薄膜5nm Ag/5nm Co，並將順序對調，觀察其高溫凝聚的差異。另外更進一步探討其中矽基板/Ag/Co膜層做成陣列時其特性研究，最後將含有磁性材料的連續膜 矽基板/Ag/Co，作不同方向外加磁場對於高溫凝聚影響的研究。
我們先將需要的膜層進行黃光曝光定義，並利用電子束蒸鍍系統鍍上所需膜層，最後在真空環境下對樣品進行加熱，再透過SEM及Auger電子縱深儀進行觀察表面形貌與元素分析。
我們發現當Co膜層在上方時，因高溫而凝聚的顆粒大且分布較散，且呈現鈷殼銀和矽在中間的現象；當Ag膜層在上方時，則凝聚的顆粒小且密，且呈現鈷銀合金的現象。將矽基板/Ag/Co做成陣列樣品後，每一陣列會凝聚成一顆顆粒，且隨著陣列面積越大，凝聚的顆粒也越大，但當陣列面積大到一定程度後，陣列上薄膜會凝聚成兩顆以上的顆粒。接著將 矽基板/Ag/Co 連續膜加熱並外加2000 Oe的磁場，發現磁場平行於膜面時，凝聚顆粒密度較疏且顆粒較大，而磁場垂直膜面時，凝聚顆粒密度較密且顆粒較小。

Our work in this thesis is divided into two parts. In the first part, we control the agglomerated area of silver nano-structure by electron wind force in electromigration. From what we can learn from the result, we propose a new type of non-volatile read-only memory device. In the next step, we mearsured the samples at high temperature, and investigated the effect of temperature on the electromigration of silver atoms.
The nano-structure was patterned by scanning electron microscope (SEM), and then we deposited silver via electron beam evaporation system. Optical microscope is used to observe the samples as the current went through, as well as measuring the voltage-current relationship of the nano-structure. We also changed the ambient temperature to observe the impact of electron wind force to silver nano-structure.
From the results of the experiment, we can decide which area of silver nano-structure we want to agglomerate by setting the direct of current based on the relation between electron wind and silver atoms. Though there is less current density, it agglomerated in the bigger cross section area, too. Because there are not only electron wind force but also the momentum of the atoms which were moved in the front of the device by electron wind force. We then measured the samples under high ambient temperature, we found that when the temperature is raised, it renders the transfer of momentum stronger.
The second part of our work focus on solid thin film dewetting at high temperature. The system can be more stable when the surface energy gets much lower, therefore solid thin film dewet from substrate and agglomerate like particles. We chose the less commonly investigated structure to study on: the bi-layer solid thin films. In this study, we fabricated 5 nm Ag/ 5 nm Co bi-layer films, and we switch the layers of the films to observe the difference of their agglomeration. Next, we investigated the patterned arrays of Si substrate/Ag/Co. Also, we applied the different direction of magnetic field when we place the continuous Ag/ Co bi-layer thin films into the chamber with high temperature.
We define the array pattern by the means of photolithography, and then we deposited 5 nm Ag/ 5 nm Co by electron beam evaporation system. After the samples were annealed in vacuum chamber, we observed their surfaces profile by SEM and their atomic concentration by Auger depth profiling.
We found that when Co layer is on top, the agglomerate particles are larger, cobalt shell and silver-silicon alloys and the density of distribution is lower. On the contrary, when Ag layer is on top, the agglomerate particles are smaller, cobalt-silver alloys and the density of distribution is higher. Then we made the patterned arrays of Si substrate/Ag/Co. We found that one patterned thin films could agglomerate one particle, and as the pattern are larger, the particle would also be larger. But when the area of patterned thin films is much bigger, one patterned thin films may agglomerate more than two particles. Next, annealed continuous Ag/ Co bi-layer thin films with 2000 Oe magnetic field, and we found that when magnetic field is parallel to the surface of the thin films, the agglomerate particles are larger and the density of distribution is lower. Otherwise, when magnetic field is perpendicular to the surface of the thin films, the agglomerate particles are smaller and the density of distribution is lower.

圖表目錄 7
第一章、緒論 10
1.1 前言 10
1.2 研究動機與目的 11
第二章、文獻回顧與理論基礎 13
2.1 電遷移效應 13
2.2 熱遷移效應 15
2.3 焦耳熱及TCR效應 15
2.4 電流集中效應 16
2.5 薄膜高溫凝聚現象 17
2.6 磁性材料 19
2.7 文獻回顧 20
第三章、實驗方法與架構 27
3.1 樣品製備 27
3.2 實驗架構 30
3.3 量測方法 33
第四章、實驗結果與討論 35
4.1 銀奈米結構電遷移及其加溫探討 35
4.1-1 銀奈米結構－樣品製備結果 35
4.1-2 銀奈米結構－電遷移量測結果與討論 36
4.1-3 銀奈米結構－升溫對電遷移量測結果與討論 42
4.2 雙層薄膜加溫及加場探討 46
4.2-1 雙層薄膜加溫凝聚－樣品製備結果 46
4.2-2 雙層薄膜加溫凝聚－正反膜層的結果與討論 47
4.2-3 雙層薄膜加溫凝聚－陣列形狀差異的結果與討論 58
4.2-4 雙層薄膜加溫凝聚－加場對加熱凝聚影響的結果與討論 62
第五章、結論 67
參考文獻 69

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