Silicon Carbide: Materials, Processing & Devices (2003)

Preface Chapter 1 Epitaxial growth of high-quality silicon carbide - Fundamentals and recent progress - -- T. Kimoto and H. Matsunami* (Kyoto University) (1) Introduction (2) Step-controlled Epitaxy of SiC 2.1 Chemical vapor deposition 2.2 Step-controlled epitaxy 2.3 Surface morphology (3) Growth mechanism of step-controlled epitaxy 3.1 Rate-determining process 3.2 Off-angle dependence of growth rate 3.3 Temperature dependence of growth rate 3.4 Prediction of step-flow growth condition 3.4.1 Surface diffusion model 3.4.2 Desorption flux 3.4.3 Critical supersaturation ratio 3.4.4 Critical growth conditions 3.4.5 Surface diffusion length 3.4.6 Prediction of growth mode (4) Behaviors of steps in SiC epitaxy 4.1 Nucleation and step motion 4.2 Step bunching (5) Characterization of epitaxial layers 5.1 Structural characterization 5.2 Optical characterization 5.3 Electrical characterization (6) Doping of impurities 6.1 Donor doping 6.2 Acceptor doping (7) Recent progress 7.1 Practical epitaxial growth 7.2 Epitaxial growth on (11-20) (8) Concludions References Chapter 2 Surface characterization of 6H-SiC reconstructions -- Kian-Ping LOH, Eng-Soon TOK, and Andrew T. S. WEE* (National University of Singapore) 1. INTRODUCTION 2. Sample preparation methods for characterization of surface reconstruction 3. Reflection High Energy Electron Diffraction (RHEED) 3.1 RHEED system set-up 3.2 RHEED analysis of surface reconstruction on 6H-SiC (0001) 3.3 6H-SiC (0001)-(1'1) reconstruction 3.4 6H-SiC (0001)-(3'3) reconstruction 3.5 6H-SiC(0001)-(6x6) reconstruction 3.6 6H-SiC(0001)-(O3'O3R ) reconstruction 3.7 1'1 graphite-R on 1'1 SiC 3.8 RHEED Rocking beam analysis 4. Scanning Tunneling Microscopy (STM) 4.1 Surface Morphological Evolution of 6H-SiC(0001) 4.2 6H-SiC (0001)-(3'3) reconstruction 4.3 6H-SiC (0001)-(6'6) reconstruction 5. X-ray Photoelectron Spectroscopy (XPS) 6. Auger electron spectroscopy (AES) 7. Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) 8. Conclusions Acknowledgements References Chap ter 3 Exciton and defect photoluminescence from SiC -- T. Egilsson, I.G. Ivanov, N.T. Son, A. Henry, J.P. Bergman, and E. Janzen* (Linkoping University) 1. Introduction 2. Experimental techniques 3. Some properties of sic 4. Electronic structure 4.1. Excitons 4.2. Internal transitions at impurity ions 5. Free excitons 6. Bound excitons 6.1. D-and A-BEs 6.2. I-BEs 7. Internal transitions References Chapter 4 DEEP LEVEL DEFECTS IN SiC MATERIALS AND DEVICES -- A. A. Lebedev* (A. F. Ioffe Physics & Technology Institute) Introduction. 1. Parameters of deep centers in SiC. 1.1. Major doping impurities in SiC 1.2. Other types of impurity centers in SiC 1.3. Intrinsic defects in silicon carbide 1.4. Radiation doping of SiC 2. Influence of impurities on the growth of epitaxial SiC layers 2.1. Heteropolytype SiC epitaxy 2.2. Site-competition epitaxy of SiC 3. Deep centers and recombination processes in SiC. 3.1. A deep centers and radiates recombination in 6H- and 4H-SiC p-n structures. 3.2. Influence of deep centers on the diffusion length and lifetime in 6H-SiC p-n structures 3.3. Deep centers and the negative temperature coefficient for the breakdown voltage in SiC p-n-structures Conclusions References Chapter 5 Ion-implantation in SiC -- Mulpuri V. Rao (George Mason University) (1) Introduction (2) Implant Profile Range Statistics (3) Surface Morphology of Annealed Material (4) Thermal Stability of Implant Depth Profiles (5) Lattice Quality - Rutherford Back-scattering (RBS) (6) Electrical Activation of Donor Implants (7) Electrical Activation of Acceptor Implants (8) Electrical Characteristics of Compensation Implants (9) Other Applications of Ion-implantation (10) Implant Masking (11) Ion-implantation for Device Applications (12) Conclusions References Chapter 6 OHMIC CONTACTS TO SiC FOR HIGH POWER AND HIGH TEMPERATURE DEVICE APPLICATIONS -- M. W. Cole * and P. C. Joshi (U.S. Army Research Laboratory) 1. INTRODUCTION 2. OHMIC CONTACTS TO SiC 2.1. Theory 2.2. Approach 2.3. Considerations and Critical Requirements 3. OHMIC CONTACTS TO n-SiC 3.1. Ti and Ti Based Metallizations 3.2. W and W Based Metallizations 3.3. Ta and Ta Based Metallizations 3.4. Re Contacts 3.5. Pt Contacts 3.6. Cr and Cr Based Metallizations 3.7. Mo and Co Silicide Metallizations 3.8. Ni and Ni Based Metallizations 4. OHMIC CONTACTS TO p-SiC 4.1. Al and Al Based Metallizations 4.2. Ti and Ti Based Metallizations 4.3. Si Based Metallizations 4.4. W and W Based Metallizations 4.5. Pd Contacts 4.6. Pt Contacts 4.7. Ta Contacts 4.8. Os, Mo, and Co Based Metallizations 4.9. B Based Metallizations 5. Conclusions References Chapter 7 SiC Avalanche Breakdown and Avalanche Photodiodes -- Feng Yan* and Jian H. Zhao (Rutgers University) 1. INTRODUCTION 2. AVALANCHE BREAKDOWN 3. ACHIEVING AVALANCHE BREAKDOWN 3.1 Defects detrimental to the avalanche breakdown of SiC 3.2 Yield of devices free of defects 3.3 Edge termination of SiC devices 3.3.1 Positive bevel with a bevel angle as low as 2o 3.3.2 Multi-step junction termination extension (MJTE) 4. DETERMINATION OF IMPACT IONIZATION RATES 4.1 Multiplication factors 4.2 Determination of impact ionization rates from multiplication factors 5. IMPACT IONIZATION RATES 5.1 Impact ionization rates of 6H-SiC 5.2 Impact ionization rates of 4H-SiC 5.3 Criteria of avalanche breakdown 5.4 Critical field and breakdown voltage of 6H-SiC pn junction 5.5 Critical field and breakdown voltage of 4H-SiC pn junction 6. 4H-SIC AVALANCHE PHOTODIODES 6.1 Noise performance of APDs 6.2 Practical consideration in SiC APD design 6.3 4H-SiC APDs edge terminated by the positive bevel 6.4 Reach-through 4H-SiC APDs terminated by MJTE 6.5 4H-SiC APD linear arrays 9. Conclusions References Chapter 8 Porous SiC Technology -- Stephen E. Saddow* (University of South Florida), Marina Mynbaeva (Ioffe Institute) and Michael F. MacMillan (Sterling Semiconductor) 1 Introduction 2 Porous SiC Technology - early works on p-type substrates 2.1 UV Luminescence and LEDS. 2.2 Infrared reflectance of porous SiC layers 2.3 Comparison of Porous SiC Reflectance to Bulk SiC Reflectance 2.4 Comparison of Data to Model Reflectance 2.5 Discussion 3 N-type Porous SiC Technology - early works 3.1 Porous SiC from n-type bulk materials 3.2 Porous layers based on epitaxial n-SiC films 3.3 Optical properties of n-type PSC 3.4 Porous n-type SiC - wafers technology 3.5 Selected properties of PSC 4 Epitaxial growth on Porous SiC 4.1 SiC epitaxial growth on porous SiC substrates - A First Report 4.2 SiC Defect Density Reduction by Epitaxy on Porous Surfaces - LTPL Observations 4.3 Structural Characterization of SiC Epitaxial Layers Grown on PSC - SWBXT and TEM 4.4 Growth of SiC Epitaxial Layers on Porous Surfaces of Varying Porosity 4.5 Scanning Acoustic Microscopy in Porous SiC 4.6 Comparison of Schottky Diode Performance on PSC and Conventional SiC 4.6.1 Schottky diode results and discussion 4.6.2 Schottky Diode Conclusion 5 Conclusions References