Sigec Heteroepitaxial Layer Growth By Low Temperature, High Purity

THE GOAL OF THE PROPOSED RESEARCH IS TO DEVELOP A PROCESS GROW DEVICE QUALITY Si-Ge-C STRAIN LAYERS HETEROEPITAXIALLY ONTO SINGLE CRYSTAL SILICON SUBSTRATES. Si-Ge-C ALLOYS WILL MAKE POSSIBLE A NEW CLASS OF HETEROJUNCTION DEVICES IN WHICH THE BANDGAP CAN BE TAILORED TO BE WIDER OR NARROWER THAN SILICON, AND IN WHICH PARTIAL OR COMPLETE STRAIN COMPENSATION IS POSSIBLE. INITIAL PROCESS DEVELOPMENT WILL BE AT THE UNIVERSITY OF CALIFORNIA AT DAVIS IN A PROTOTYPE ULTRA-HIGH VACUUM CHEMICAL VAPOR DEPOSITION REACTOR WITH PURIFIED GAS SOURCES. SINCE CARBON MUST BE INCORPORATED INTO SILICON IN EXCESS OF ITS SOLUBILITY LIMIT, DEPOSITION WILL BE AT THE LOWEST POSSIBLE TEMPERATURE, <700 DEGREE. PROPERTIES WILL BE MEASURED AND DEPOSITION PARAMETERS VARIED TO OPTIMIZE THE LAYERS. THE DEPOSITED LAYERS WILL BE CHARACTERIZED BY OPTICAL MICROSCOPY, SEM, TEM, AES, HIGH RESOLUTION XRD, SRP, PHOTOLUMINESCENCE AND PHOTOABSORPTION. WHEN INITIAL PROCESS CONDITIONS HAVE BEEN ESTABLISHED IN THE UHV/CVD SYSTEM, A PARALLEL DEVELOPMENT WILL BE STARTED AT LAWRENCE SEMICONDUCTOR RESEARCH LABORATORIES (LSRL) USING AN EPSILON ONE, SINGLE WAFER AUTOMATED CVD REACTOR. THE EPSILON ONE ALSO OPERATES WITH HIGH PURITY GAS SOURCES, AND HAS PREVIOUSLY DEMONSTRATED Si-Ge EPITAXIAL LAYER GROWTH AT TEMPERATURES AS LOW AS 600 C DEGREE. THE ULTIMATE GOAL IS TO ESTABLISH LSRL AS A SUPPLIER OF CUSTOM Si-Ge-C HETEROSTRUCTURES TO COMMERCIAL CUSTOMERS AND TO GOVERNMENT CONTRACTORS AND AGENCIES.