臺灣博碩士論文加值系統

我們提出了一種利用金奈米顆粒的自組裝 (self-assembly) 現象以由下而上(bottom-up)的方式來製作單電子電晶體 (single-electron transistors) 的方法。此自組裝乃是檸檬酸鹽 (citrate) 溶液中的金奈米顆粒以動力學方式堆積所產生的現象。利用此自組裝的機制，金奈米顆粒會組裝成具有極小間距的碎形(fractal)結構。再者，由於奈米尺寸的顆粒具有很小的電容 (capacitance)，此時電子穿隧 (tunnel) 進入奈米顆粒所產生的充電效應 (charging effect) 將可以容易的被觀察到。利用自組裝的機制及充電效應，我們製作出以金奈米顆粒為中央島 (island) 的單電子電晶體。此論文的主要工作內容包涵兩大部份，第一個部份是探討金奈米顆粒自組裝的機制；第二部份是應用此機制製作成單電子電晶體，並量測其特性。這些單電子電晶體電子元件表現出了明顯的庫倫阻斷現象 (coulomb blockade) 而且操作溫度可達155K。

We present a bottom-up method for fabrication of single-electron transistors by utilizing self-assembly of gold nanoparticles. The self-assembly is driven by the kinetic aggregation of gold nanoparticles in citrate solution. With this mechanism, gold nanoparticles are assembled into fractal structures with very small gap in between particles. Moreover, because of the small capacitance associated with the nano sized particles, the charging effect for electrons to tunnel into the particles become appreciable. Making use of the self-assembly mechanism and the charging effect, we made single electron transistors with gold particle islands. This thesis work is divided into two parts: the first part is to investigate the mechanism in the self-assembly of gold particles; the second part is to apply this mechanism to fabricate the single-electron transistors. These devices exhibited prominent Coulomb blockade behavior which persisted up to 155 K.

1. INTRODUCTION………………………………... 1
1.1 Background and Motivation………………………… 1
1.2 Fundamental of Single-Electron Transistor………... 1
1.2.1 Coulomb Blockade………………………........... 5
1.2.2 Coulomb Oscillation…………………………… 7
1.3 Why do we use Self-Assembly………………………. 8
1.4 Self-Assembly inspired SETs………………………... 8
2. MATERIALS AND METHODS………………… 11
2.1 Synthesis of Au Nanoparticles………………………. 11
2.2 Self-Assembly of Au Nanoparticles…………………. 12
2.3 Fabrication of External Leads………………………. 13
2.4 Deposition of Au particle formed Fractal Structure 14
2.5 Fabrication of Inner Leads………………………….. 15
3. EXPERIMENT RESULT………………………… 17
4. CONCLUSION…………………………………… 19
5. REFERENCE……………………………………... 20

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