Characterisation and crystal growth of GaAs and AlxGa1-xAs epilayers on [100] GaAs by liquid phase epitaxy (LPE).

by Clive Hau Ming Shiu.On t.p., "x" and "1-x" are subscript.Thesis (M.Phil.)--Chinese University of Hong Kong, 1994.Includes bibliographical references (leaves [126]-[130]).ACKNOWLEDGEMENT --- p.iABSTRACT --- p.iiTABLE OF CONTENTS --- p.iiiChapter Chapter 1 --- INTRODUCTION --- p.1Chapter Chapter 2 --- THEORY --- p.3Chapter 2.1 --- Fundamentals of GaAs and AlGaAs --- p.3Chapter 2.1.1 --- Crystal structure and properties of GaAs --- p.4Chapter 2.1.2 --- General properties of GaAs at 300K --- p.5Chapter 2.1.3 --- Temperature dependence of bandgap for GaAs --- p.6Chapter 2.1.4 --- Dopants of GaAs --- p.7Chapter 2.1.5 --- Properties of AlGaAs --- p.8Chapter 2.2 --- Phase Equilibrium of GaAs and AlGaAs --- p.10Chapter 2.2.1 --- Phase diagram of Ga-As binary system --- p.11Chapter 2.2.2 --- Phase diagram of Al-Ga-As ternary system --- p.13Chapter 2.3 --- Principle of LPE growth --- p.17Chapter 2.3.1 --- General concept of liquid phase epitaxy --- p.17Chapter 2.3.2 --- Fundamental methods of LPE growth --- p.19Chapter 2.4 --- Dopants in GaAs and AlGaAs system --- p.21Chapter 2.4.1 --- Common dopants in GaAs --- p.22Chapter 2.4.2 --- Tellurium in GaAs --- p.23Chapter 2.4.3 --- Silicon in GaAs --- p.24Chapter 2.4.4 --- Tellurium and Tin in AlGaAs --- p.26Chapter Chapter 3 --- LPE SYSTEM FOR GaAs AND AlGaAs --- p.28Chapter 3.1 --- Basic requirements for horizontal sliding LPE system --- p.30Chapter 3.2 --- Cleaning process of the LPE system --- p.37Chapter 3.2.1 --- Cleaning procedures of the quartz parts --- p.37Chapter 3.2.2 --- Cleaning procedures of the stainless steel tubing --- p.38Chapter 3.2.3 --- Cleaning procedures of the graphite boat --- p.39Chapter 3.3 --- Final examination for LPE growth --- p.41Chapter 3.3.1 --- Examining the sealing of the system --- p.41Chapter 3.3.2 --- Examining the palladium hydrogen purifier --- p.41Chapter 3.3.2.1 --- Measuring the dew point --- p.41Chapter 3.3.2.2 --- Measuring the content of oxygen and nitrogen --- p.42Chapter 3.3.3 --- Adjusting and measuring the isothermal zone in the fumace --- p.42Chapter 3.3.4 --- Measuring of background impurity --- p.43Chapter 3.3.5 --- Inspection of the operating chamber --- p.44Chapter Chapter 4 --- EXPERIMENTALS --- p.45Chapter 4.1 --- Determination of GaAs and AlGaAs content in the source melt --- p.45Chapter 4.2 --- Calculation of GaAs and AlGaAs content in the source melt --- p.45Chapter 4.3 --- Experimental determination of source melt composition --- p.48Chapter 4.4 --- LPE growth method --- p.49Chapter 4.5 --- Thickness control of LPE epilayers --- p.49Chapter 4.6 --- Experimental procedures --- p.50Chapter Chapter 5 --- RESULTS AND DISCUSSIONS --- p.63Chapter 5.1 --- Growth condition studies of GaAs --- p.63Chapter 5.1.1 --- Experimental --- p.63Chapter 5.1.2 --- Phase equilibrium of GaAs in the range of 780 to 840 °C --- p.63Chapter 5.1.3 --- Results of undoped GaAs epilayers --- p.67Chapter 5.1.4 --- Results of Si doped GaAs epilayers --- p.72Chapter 5.2 --- Growth condition studies of AlxGa1-xAs for x=0.1 to 09 --- p.73Chapter 5.2.1 --- Phase equilibrium of AlxGa1-xAs for x=0.1 to 09 --- p.73Chapter 5.2.2 --- Relation between saturation of solution and he flatness of interface between epilayer and substrate --- p.79Chapter 5.2.3 --- Determination of composition x in AlxGa1-xAs --- p.82Chapter 5.2.4 --- Relation between epilayer thickness and x in AlxGa1-xAs --- p.84Chapter 5.3 --- High AlxGa1-xAs with x ´ 0.9 ° at 780 °C --- p.87Chapter 5.3.1 --- Deposition rate of high AlxGa1-xAs epilayer versus cooling rate --- p.87Chapter 5.3.2 --- Thickness profiles of epilayers versus cooling rate --- p.89Chapter 5.3.3 --- Spectroscopic refractive index of high AlxGa1-xAs in the visible light spectrum --- p.94Chapter 5.3.4 --- Rocking curves of high AlxGa1-xAs --- p.96Chapter 5.4 --- Tellurium doped AlxGa1-xAs with x ranging from 0.1 to 09 --- p.98Chapter 5.4.1 --- Carrier concentration versus composition x in AlxGa1-xAs --- p.98Chapter 5.4.2 --- Carrier concentration of Al0.3Ga0.7As versus Te mole fraction --- p.100Chapter 5.4.3 --- Donor activation energy of Te Versus x in AlxGa1-xAs --- p.102Chapter 5.4.4 --- Refractive index of Te doped AlxGa1-xAs at 300K --- p.105Chapter 5.4.5 --- Dependence of solubility upon Te doping level --- p.106Chapter 5.5 --- Heavily tellurium doped Al0.3Ga0.7As --- p.107Chapter 5.5.1 --- Diffractometry study of heavily Te doped Al0.3Ga0.7As --- p.108Chapter 5.5.2 --- Morphological studies and interface studies of heavily Te doped Al0.3Ga0.7As --- p.112Chapter Chapter 6 --- CONCLUSION --- p.119APPENDIX Photoluminance Analysis at room temperatureREFERENC