1  Introduction

1.1 Introduction: gallium nitride and related alloys (III-nitrides)
1.2 GaN applications and characteristics
1.3 Physical properties of III-nitrides
1.3.1 Crystal structure
1.3.2 Mechanical properties
1.3.3 Hetero-epitaxial relations with substrates
1.4 Defects in III-nitrides
1.4.1 Dislocations
1.5 Outline of the thesis