OBJECTIVES SUMMARY: WE PROPOSE THE DEVELOPMENT AND USE OF HYBRID INTEGRATED SILICON PHOTONIC CIRCUITS FOR HIGH-SPEED FREE-SPACE OPTICAL COMMUNICATION AND SPACE SENSING TECHNOLOGIES. BASED ON THE SCALABLE SILICON NANOPHOTONIC PLATFORM THREE DIMENSIONAL NANOPHOTONIC DEVICES CONFIGURATIONS WILL BE DESIGNED AND INTEGRATION TECHNIQUES WILL BE DEVELOPED FOR CONVERTING THE SPECIALIZED PROPERTIES OF HYBRID INTEGRATED MATERIALS TO DESIRED ENGINEERING PURPOSES. METHODOLOGY SUMMARY: CMOS MANUFACTURING OFFERS WAFER SCALE FABRICATION OF SILICON WITH SUB-10NM FEATURES AND ATOMIC-SCALE SURFACE ROUGHNESS. AS INDIVIDUAL DEVICE SPEED/SENSITIVITY IS LIMITED BY THE INTRINSIC PROPERTIES OF SILICON COMPLEX DESIGNS INVOLVING CASCADED MULTI-LEVEL CIRCUITS HAVE BEEN DEVELOPED TO FURTHER IMPROVE THE BANDWIDTH AND OTHER PERFORMANCE METRICS. TO REDUCE CIRCUIT COMPLEXITY HYBRID MATERIALS WITH HIGH NONLINEAR COEFFICIENTS ARE PROPOSED FOR DIRECT INTEGRATION ONTO SILICON NANOPHOTONIC PLATFORM. WE BELIEVE THAT HYBRID INTEGRATION CAN FUNDAMENTALLY IMPROVE EFFICIENCY DEVICE SPEED IN ADDITION TO INTRODUCING OTHER DESIRED FUNCTIONALITIES ONTO THE SILICON PLATFORM SUCH AS IONIZATION RADIATION DETECTION. THE RADIATION-INDUCED ELECTRONIC/PHOTONIC PERTURBATIONS IN THE ACTIVE MEDIUM CAN BE CAPTURED BY THE ELECTRONIC JUNCTIONS IN SILICON LAYER TO MAINTAIN THE PRISTINE QUALITY OF THE ACTIVE LAYER. ADDITIONALLY DEVICE SENSITIVITY CAN BE INCREASED THROUGH RESONANCE ENHANCEMENT DESIGNS IN THE SILICON LAYER THROUGH VARIOUS LIGHT-TRAPPING SCHEMES. RELEVANCE SUMMARY: THE MINIATURIZED PHOTONIC INSTRUMENTS FOR SENSING AND COMMUNICATION COULD SIGNIFICANTLY REDUCE SIZES WEIGHT AND POWER COMPARED TO EXISTING TECHNOLOGIES AND DIRECTLY RELATES TO SEVERAL TECHNOLOGY AREAS (TA) ON NASA S TECHNOLOGY ROADMAP INCLUDING TA 5.1 OPTICAL COMMUNICATIONS AND NAVIGATION AND TA 8.3 IN-SITU INSTRUMENTS AND SENSORS. THE ON-CHIP PHOTONIC TRANSCEIVER IS POTENTIAL TO CONTRIBUTE TO THE LASER COMMUNICATIONS RELAY DEMONSTRATION MISSION AT GODDARD SPACE FLIGHT CENTER WITH LAUNCH READINESS YEAR OF 2019. THE SENSOR DEVELOPMENT IS INSPIRED BY THE INSTRUMENTS ON CURRENT MISSIONS OF MAGNETOSPHERIC MULTISCALE MISSION AND REUVEN RAMATY HIGH ENERGY SOLAR SPECTROSCOPIC IMAGER. THE PROPOSED X-RAY UV AND IR DETECTOR ARRAYS COULD BE USED FOR TWO MAJOR STRATEGIC SURVEYOR MISSIONS WITH ESTIMATED LAUNCH DATE IN 2035 AS DESCRIBED IN NASA S TECHNOLOGY ROADMAP. WORK SUMMARY: WE PROPOSE IN THIS THREE-YEAR EFFORT TO DEVELOP NEW SCALABLE HYBRID INTEGRATION TECHNIQUES THAT INCORPORATE NONLINEAR CRYSTAL MATERIALS WITH STANDARD CMOS SILICON PROCESSING TO REALIZE NOVEL DEVICES AND INSTRUMENTS. WE WILL APPLY THESE NEW METHODS TOWARDS THE DETECTION/IMAGING OF IONIZATION RADIATION AND OTHER CHARGED PARTICLES FOR SPACE WEATHER OBSERVATIONS AND HIGH-SPEED OPTICAL COMMUNICATION. THE SPECIFIC OBJECTIVES ARE (1) TO DESIGN NEW DEVICE CONFIGURATIONS THAT COMBINE CMOS FOUNDRY FABRICATED ADVANCED SUBSTRATES AND THIN FILM MATERIALS WITH DESIRED FUNCTIONALITIES; (2) TO ENGINEER THE DIRECT CONTACT INTERFACE BETWEEN HYBRID INTEGRATED MATERIALS AND SILICON TOP SURFACES PROCESSED IN A CMOS FOUNDRY. WE WILL ALSO DEVELOP A HIGH-PERFORMANCE INTEGRATION TECHNOLOGY FOR EFFICIENT INTERLAYER COUPLING; (3) TO EVALUATE AND OPTIMIZE DEVICE BANDWIDTH SENSITIVITY AND RELIABILITY FOR HIGH DATA RATE COMMUNICATION APPLICATIONS AND RADIATION SENSING APPLICATIONS; (4) TO COMPILE THE OPTIMIZED DEVICE CONFIGURATIONS INTO A PHOTONIC DESIGN KIT (PDK) THAT COULD BE USED BY NASA SCIENTISTS AS PART OF A LIBRARY SPECIALIZED FOR SPACE INSTRUMENTATIONS.