鄭鴻祥臺灣大學：電子工程學研究所鄭聰翰Cheng, Tsung-HanTsung-HanCheng2007-11-272018-07-102007-11-272018-07-102007http://ntur.lib.ntu.edu.tw//handle/246246/57358矽鍺材料具有能與矽基半導體工業整合的優點。由於擁有高電子遷移率、負電組特性及良好高頻響應的特性，近年矽鍺材料及電子元件，以躍升成為半導體工業界的寵兒，並以應用在手機、射頻技術、全球定位系統、功率放大器、無線網路、動態隨機存取記憶體、靜態隨機存取記憶體等等。此外，隨者磊晶技術的成熟，許多小尺寸的量子元件已可成功製照。在本文中，我們將報告一種利用矽/矽鍺異質結構製作而成的量子元件-共振穿隧二極體。Silicon/Silicon Germanium(Si/SiGe) has the advantage of being fully compatible with the Si based semiconductor industry. In recent years, SiGe has became much attractive for its properties of high electron mobility, NDR properties and good high-frequency response and has been applied in mobile phone, radio frequency(RF) technology, global positioning system(GPS), power amplifier(PA), wireless LAN, SRAM DRAM technology and so on. Besides, with the progress of the growth technology, many quantum devices with small sizes have been accomplished. In this thesis, one of the quantum devices, the resonant tunneling diodes(RTDs), with Si/SiGe heterostructure operating at low and room temperature are reported.Contents Chapter 1 Introduction and motivations 1 1.1 Introduction 1 1.2 Motivation 2 References 6 Chapter 2 Theory of Resonant Tunneling Diodes 7 2.1 Band Structure of Si/SiGe Heterostructure 7 2.1.1 Introduction to Strain Effect 7 2.1.2 Strain Effect on the Valence band of SiGE 10 2.1.3 Strain Effect on the Conduction band of SiGe 11 2.1.4 Band Alignment of SiGe/Si/SiGe 13 2.2 Principle of Resonant Tunneling Diodes 15 2.2.1 Double Barrier Quantum Well Structure 15 2.2.2 Processes in RTDs 16 2.3 Negative Differential Resistance Characteristics 17 2.3.1 Transmission Coefficient 17 2.3.2 Current-Voltage Characteristics 20 References 23 Chapter 3 Fabrication of Si/SiGe RTDs and Measurement Setup 25 3.1 Sample Preparation 25 3.2 Fabrication Processes 28 3.2.1 Sample Cleaning 28 3.2.2 First Photolithography for Mesa Pattern 29 3.2.3 Dry Etching of the Mesa 33 3.2.4 Second Photolithography for Metal Contact 34 3.2.5 Metal Evaporating 34 3.2.6 Lift off 35 3.2.7 Annealing for Ohmic Contact 35 3.3 Instrument Setup for Measurement 36 3.3.1 Current-Voltage (I-V) 36 3.3.2 Measurement with Varying Temperature 36 References 37 Chapter 4 Results and Discussions 39 4.1 Experimental Results of N698 39 4.2 Simulations 47 4.2.1 Finite element calculation of the schordinger equation 47 4.2.2 Peak to Valley Current Ration 53 References 54 Chapter 5 Conclusions and Future work 56 5.1 Conclusions 56 5.2 Suggestion for Future Work 57 Appendix A: Parameters 59en-US共振穿隧元件Resonant tunneling diodethesis