Structural and Optical Characteristics of Epitaxially Grown SiGe on Si for Electronic and Photonic Device Applications

Abstract

For higher device performances including low-power consumption and high-speed operation, functional materials in wide variety are actively studied. In particular, Si compatibility is regarded as one of the indispensable prerequisites owing to cost effectiveness and high maturity of Si platform and its process integration. SiGe is gaining much interest owing to Si compatibility, high carrier mobilities, and higher optical confinement capability compared with Si. In this work, SiGe layers have been epitaxially grown on Si substrate under different conditions and their structural and optical characteristics are analyzed in depth. Various analysis tools are used cooperatively, including high-resolution transmission electron microscopy (HR-TEM), dynamic secondary ion mass spectroscopy (SIMS), X-ray diffraction spectroscopy (XRD), and long-wavelength ellipsometer, in order to extract the thickness as the result of epitaxy condition, Ge fraction, interface status, lattice constant, and refractive index with extinction coefficient for setting up parameter database for electronic and photonic device applications.