Amorphous matrix effects on silicon nanoparticles

Abstract

The search for new materials is a vital endeavor, as the world demands more from the technologies available, new technologies must be developed. As current semiconductors are pushed to their operating limits, the need for new wider bandgap semiconductor technology has become apparent. In this work, the quantum confinement of silicon quantum dots (SiQDs) in various semiconductor materials was examined. The chosen materials were the wide bandgap semiconductor amorphous silicon carbide (SiC) as well as amorphous silicon synthesized using plasma enhanced chemical vapor deposition (PECVD). Amorphous silicon carbide is an interesting material as it has a similar band structure to silicon while functioning in higher temperature and operating power conditions due to it's larger bandgap. The measurement of confinement of the dots was attempted using photoluminescence (PL) and spectroscopic ellipsometry (SE). In addition to measuring quantum confinement, since SiC had not yet been synthesized using the PECVD system in this work, a literature review was conducted to both determine the feasibility and capabilities of growing the SiC films. After the review was finished, the PECVD system was modied to allow for the growth of SiC films both with and without SiQDs. Once growth of the films was complete, the films had to be characterized to determine if the growths were successful. This was accomplished using Fourier transform infrared (FTIR) spectroscopy and SE. Growth and characterization of the SiC films was successful. Growth of SiC films containing SiQDs was also accomplished in this work, while the measurement of confinement of the SiQDs within yielded varying levels of success. Quantum confinement was successfully observed with the SiQDs bandgap increasing to between 1.2 and 1.3 eV, however no signicant differences in bandgap were observed as the surrounding matrix was changed.