本論文的目的是利用聚焦離子束技術加工出約瑟芬收縮結。我們製作出具有SQUID或SET架構的樣品，利用SQUID結構調控磁通量，進而影響樣品超導電子波函數相位差；利用SET結構觀測以此技術是否能製作出具有充電能量的結構。
在製程上以聚焦離子束技術製作了長度落在18-54 nm、寬度落在 11-31nm的收縮處。實驗數據顯示並無形成量子點接觸，樣品表現出類似約瑟芬結的特性，臨界電流在 40 -179 μA間，對應的約瑟芬能量EJ≅82 367 meV；樣品也表現出類似庫侖阻塞的特性，充電能量EC≅1.8 meV。
我們認為以聚焦離子束技術加工收縮結，能製作出具有EJ、EC的結構。而在未來的工作上可以提升製程精度以製作出量子點接觸。

In this work, we attempt to fabricate Josephson constrict junction by using focused ion beam technology. We fabricated samples with SQUID or SET architecture, and used the SQUID structure to control the magnetic flux, thereby affecting the phase difference of superconducting electric wave function; using the SET structure to observe whether this technology can create a structure with charging energy.
We fabricated constrict junctions with a length of 18-54nm and a width of 11-31nm.The measured data show that the samples does not form a quantum point contact. The samples exhibit Josephson-like behavior. The critical current is between 40-179 μA,corresponding to the Josephson energy E_J of about 82-367 meV. The samples also exhibit Coulomb blockade-like behavior, and the charging energy E_C of about 1.8 meV.
We believe that the Josephson constrict junction is processed by focused ion beam technology can fabricate structures with E_J and E_C.For future works, the precision of the fabrication can be improved to fabricate quantum point contact.

第一章　超導基本物理與約瑟芬效應 1
1.1　超導體之基本原理 1
1.2　約瑟芬穿隧結（Josephson tunnel junction） 3
1.2.1 約瑟芬穿隧結 3
1.2.2約瑟芬結的動力學（Dynamics of a Josephson Junction） 4
1.2.3電阻電容分流結模型（Resistively Capacitively Shunted Junction model）（RCSJ model） 4
1.3超導單電子電晶體（Superconducting Single Electron Transistor） 7
1.4直流超導量子干涉儀（DC-SQUID） 9
1.5研究動機 10
第二章　約瑟芬收縮結 13
2.1　約瑟芬收縮結（Josephson constrict junction） 13
2.2　安德列夫反射（Andreev reflection） 16
2.3　安德列夫束縛態（Andreev bound state） 18
2.4　超導量子點接觸（Superconducting quantum point contact） 20
2.5　文獻回顧 23
第三章　樣品設計與製造 25
3.1聚焦離子束系統（Focused ion-beam system）(FIB) 25
3.1.1聚焦離子束的原理及應用 25
3.1.2聚焦離子束製程與其他圖樣化製程的比較 30
3.1.3聚焦離子束製程對樣品製備的影響 33
3.2樣品構想 36
3.3樣品製作流程 37
第四章　實驗量測 46
4.1實驗架設 46
4.2實驗數據與討論 47
4.2.1在系統最低溫（T=0.03K）的基本特性 47
4.2.2不同溫度下的電流－電壓特性 51
4.2.3磁通量調控收縮結相位差 54
4.3結論 57
第五章　總結與未來展望 58
參考文獻 59
附錄A 63

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