李嗣涔臺灣大學:電子工程學研究所陳昱帆Chen, Yu-FanYu-FanChen2010-07-142018-07-102010-07-142018-07-102008U0001-2507200822294200http://ntur.lib.ntu.edu.tw//handle/246246/189051本論文研究利用化學氣相沉積法經由VLS成長機制來成長電場導向及自組裝之未摻雜及微量摻雜的矽奈米線。並觀察到矽奈米線的成長會導向於外加相鄰電極間的局部電場並且跨接兩端電極。此外,我們發現鈦為一種適合電場導向成長矽奈米線的電極材料,並且能在經過兩階段快速熱退火處理後使電極與矽奈米線之間形成歐姆接觸。最後,藉由聚焦離子束輔助白金沉積,白金電極成功的被圖案化在矽奈米線上。再結合Conductive-AFM和TLM量測,可得到矽奈米線之電性以及鈦電極與矽奈米線之間的接觸電阻。Electric-field-directed growth and self-assembly of undoped and lightly p-type doped silicon nanowires by chemical-vapor deposition via the vapor-liquid-solid (VLS) growth mechanism in a low pressure chemical vapor deposition (LPCVD) system is demonstrated. The nanowires appeared to align with the localized DC electric field and grew across the gap between two electrodes. Moreover, it is found that titanium is an adequate electrode material for electric-field-directed growth of silicon nanowires, and good ohmic contact between SiNWs and Ti electrode is achieved by means of two stage rapid thermal anneal. With the application of focus ion beam assisted platinum deposition, the platinum pad is patterned on the silicon nanowire. Combined with Conductive-AFM and transmission line measurement, the measurement of the electrical characteristics of silicon nanowire and contact resistance between nanowire and Ti electrode is carried out.Chapter 1 Introduction................................................................................................1hapter 2 Experimental..............................................................................................5.1 Deposition system...................................................................................................5.1.1 Low pressure chemical vapor deposition (LPCVD)..................................5.2 Preparation.............................................................................................................7.3 Deposition Procedures............................................................................................9.4 Device Fabrication................................................................................................10.5 Dual Beam Focus Ion Beam System...................................................................11.5.1 Operation principle of Focus Ion Beam....................................................11.5.2 Basic function and application...................................................................12.5.3 Dual Beam Focus ion beam........................................................................13.6 Measurement Techniques....................................................................................15.6.1 Current – Voltage characteristics..............................................................15.6.2 Thickness Measurement of Metal electrodes............................................15.6.3 Characterization of Silicon Nanowires..................................................... 15.6.4 Electrical properties measurement of single nanowire............................15hapter 3 The Electric-Field-Directed Growth of Silicon Nanowires on Different Materials of Electrode and Ohmic Contact Formation...................17.1 Vapor-Liquid-Solid (VLS) Mechanism...............................................................18.1.1 VLS- assisted silicon nanowire growth......................................................19.1.2 The role of the metal catalyst.....................................................................25.2 Electric-Field-Directed Growth of Silicon Nanowires......................................27.3 Sample Preparation..............................................................................................29.4 Results and Discussion.........................................................................................40.4.1 The growth of undoped SiNWs on Mo electrode............................................40.4.2 The growth of SiNWs on different materials of electrode.............................44.4.2-1 The growth of p-type doped SiNWs on the Al electrode....................47.4.2-2 The growth of undoped SiNWs on the Ni electrode...........................49.4.2-3 The growth of undoped SiNWs on the Ti electrode...........................53.4.2-4 The growth of lightly p-type doped SiNWs on the Ti electrode........57.4.2-5 Conclusions............................................................................................61.4.3 Ohmic contact formation.................................................................................62.4.3-1 Nearly ohmic contact with undoped silicon nanowire.......................65.4.3-2 Ohmic contact with lightly p-type doped silcon nanowire................69hapter 4 Contact Resistance Measurement...........................................................73.1 Contact resistance measurement by Transmission Line Model.......................73.2 Focus ion beam (FIB) assisted platinum deposition..........................................75.2.1 Operation principle of Focused Ion Beam...............................................75.2.2 Ion beam assisted platinum deposition.....................................................75.2.3 Experiment..................................................................................................76.3 Electrical characteristics of single silicon nanowire measured by conductive atomic force microscope (C-AFM)......................................................................79.3.1 Operation principle of AFM.......................................................................79.3.2 Operation principle of contact mode AFM...............................................79.3.3 Operation principle of Conductive AFM..................................................80.3.4 Experiment..................................................................................................80.4 Results and Discussion.........................................................................................86.4.1 The electrical characteristics and contact resistance measurement of undoped silicon nanowire..........................................................................86.4.2 The electrical characteristics and contact resistance measurement of lightly p-type doped silicon nanowire.......................................................90.4.3 Conclusions..................................................................................................94hapter 5 Conclusions...............................................................................................98eference...................................................................................................................100ppendix A................................................................................................................1064087516 bytesapplication/pdfen-US矽奈米線歐姆接觸NanowiresOhmic Contact電場導向矽奈米線之電性與歐姆接觸研究The Electrical Characteristics of the Electric-Field Directed Growth of Silicon Nanowires and Ohmic Contact Formationthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/189051/1/ntu-97-R95943050-1.pdf