- •ACKNOWLEDGMENTS
- •TABLE OF CONTENTS
- •LIST OF TABLES
- •LIST OF FIGURES
- •INTRODUCTION
- •2.1.1 Structural Properties
- •2.1.2 Physical Properties
- •2.1.3 Electrical Properties of InN
- •2.1.3.1 Background Defects
- •2.1.4 Optical Properties of InN
- •2.2.1 Thermodynamic Models in Solid Solution
- •2.2.1.1 Regular Solution Model
- •2.2.1.2 Bonding in Semiconductor Solid Solutions Model
- •2.2.1.4 Strain Energy Model
- •2.2.1.5 First-Principal Models
- •2.2.2 Thermodynamic Analysis of InN
- •2.2.3 Phase Separation in InxGa1-xN
- •2.3.1 Growth Temperature and V/III Ratio
- •2.3.2 Nitrogen Source
- •2.4 Indium Nitride (InN) Growth Techniques
- •2.4.1 Chemical Vapor Deposition (CVD)
- •2.4.1.1 Metal-Organic Vapor Phase Epitaxy (MOVPE)
- •2.4.1.2 Hydride Vapor Phase Epitaxy (HVPE)
- •2.4.1.3 Plasma Enhanced Chemical Vapor Deposition (PECVD)
- •2.4.3 Atomic Layer Deposition (ALD)
- •2.5 Substrate Materials
- •2.5.1 Sapphire Substrate (Al2O3) (0001)
- •2.5.2 Silicon (Si) Substrate
- •2.5.4 Other Substrates
- •2.5.5 Buffer Layer
- •2.6 Summary for Growth of InN on Different Substrate
- •2.6.2 Growth on Silicon (Si) Substrate
- •2.6.3 Growth on Gallium Arsenide (GaAs) Substrate
- •2.6.4 Growth on Gallium Phosphorus (GaP) Substrate
- •2.7 Overview
- •THERMODYNAMIC ANALYSIS OF InN AND InXGa1-XN MOVPE GROWTH
- •3.1 Thermodynamic Analysis of InN and InxGa1-xN
- •3.1.1 Reaction Mechanism and Kinetics of InN MOVPE
- •3.2.1 Boundary Passivation Method with Hydrogen
- •5.1. Indium Nitride (InN) Growth Optimization
- •5.1.1. Substrate Selection
- •5.1.1.1. Sapphire (c-Al2O3 (0001))
- •5.1.1.2. Gallium Nitride (GaN/c-Al2O3 (0001))
- •5.1.1.3. Silicon (Si (111))
- •5.1.2. Substrate Preparation Procedure
- •5.1.3. Metal-Organic Vapor Phase Epitaxy (MOVPE) Reactor
- •5.1.4. Growth Chemistry and Conditions for InN Growth
- •5.1.5. Indium Nitride (InN) Growth and Optimization
- •5.1.5.1. Influence of Growth Temperature
- •5.1.5.2. Influence of Substrate Nitridation
- •5.1.5.3. Influence of N/In Ratio
- •5.1.5.4. Influence of Buffer Layer and Morphological Study
- •5.1.5.5. Influence of Pressure
- •5.1.5.6. Optical and Electrical Properties
- •5.1.5.7. Summary
- •5.1.6. Indium Nitride (InN) Droplet Formation
- •5.1.7. Annealing Effect
- •5.3. Inlet Tube Modification and Growth Results
- •CONCLUSIONS
- •LIST OF REFERENCES
- •BIOGRAPHICAL SKETCH
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2.7 Overview
The latest lattice constant of single crystal InN with wurtzite was reported to be a = 3.537 Å and c = 5.704 Å [Dav02a]. The band-gap energy of InN is nowadays accepted to ~ 0.7 eV instead of 1.89 eV.
Thermodynamic analysis helped us to understand at which growth condition the growth and etching happen and therefore help us to predict where InN film can be grown before the epitaxial growth is performed.
The possible candidates as N precursor were reviewed due to low decomposition efficiency of NH3 at low growth temperature of InN (~ 550 oC). Because all of other candidates for nitrogen source have the several problems such as toxicity, explosion and contamination, NH3 is still widely used N precursor and N2 carrier gas is better than H2 as carrier gas.
MOVPE is still the most widely used growth technique for InN for the industry and academy to date.
Based on available published data, the typical range of FWHM of XRC for single crystalline InN grown by MOVPE is higher than 2000 arcsec [Yam04a]. For Si substrate, it is still very difficult to have the high crystalline InN because of the bad coverage of InN on Si substrate despite of a small lattice mismatch [this topic was not reviewed in the InN growth on Si substrates section]. Therefore the study for the growth high quality single crystalline InN has been still required.
It is found that some factors such as growth temperature, V/III ratio, substrate, nitridation treatment, buffer layer, and flow pattern of source gases can have an effect on the structural quality of InN film. Based on the results of this review, these factors will be analyzed in detail to conduct our experiments of InN growth by MOVPE.