Investigation of novel semiconductor heterostructure systems: I. Cerium oxide/silicon heterostructures II. 6.1 A semiconductor-based avalanche photodiodes

The work presented in this thesis concerns the development of two different semiconductor heterostructure technologies.;Part I describes research in the CeO2/silicon heterostructure system. Details are presented concerning the growth of CeO2 on silicon and the reactions that take place at the CeO2/silicon interface. The evolution of this interface as a function of annealing temperature and annealing ambient are studied via in situ x-ray photoelectron spectroscopy (XPS). Studies of metal-CeO2-silicon capacitors are also presented which help to determine the usefulness of this oxide as an alternative gate dielectric for silicon-based device applications.;Part II involves research into the fabrication of avalanche photodiodes (APD's) utilizing the 6.1 A semiconductor system. Certain alloys of AlxGa1-xSb are shown to greatly favor hole multiplication which is beneficial for both noise characteristics and gain-bandwidth product. Further, details are presented on the current investigation into using 6.1 A superlattices to achieve even more desirable detector performance.