Abstract
Epitaxial Growth and Fundamental Properties of III-Nitride Semiconductors Abstract The III-nitrides semiconductors AlN, GaN, and InN are promising wide-band-gap semiconductors for optoelectronic applications. Large bond ionicity and crystalline asymmetry in z-axis produce macroscopic polarizations in wurtzite-type III-nitrides and therefore strong piezoelectric and spontaneous polarization strongly affect the III-nitrides thin films and polar III-nitride heterointerfaces. In chapter 1, we will introduce the crystal properties and polarization effects in III-nitrides semiconductors. Next, experimental methods used in this thesis will be briefly discussed in chapter 2. The design and growth of high quality III-Nitrides structures for the propose of study their crystal properties, polarization effects and electronic structures are described in chapter 3. Because unwanted surface contaminations may influence the intrinsic properties, we performed in situ SR-PES measurements on InN. The electronic structures of contamination-free InN surface is discussed in chapter 4. The integration of the unique properties of III-nitrides semiconductors with the mature silicon technology is very attractive and the high quality III-nitrides epilayers can be grown on silicon substrate by utilizing a Si3N4 buffer layer. Therefore, the growth of Si3N4 on Si substrate by nitrogen plasma source and its valence band offset and interface stoichiometry will be studied in Chapter 5.