THE MIT KAVLI INSTITUTE FOR ASTROPHYSICS AND SPACE RESEARCH (MKI) INTENDS TO SUBMIT A PROPOSAL TO THE RESEARCH OPPORTUNITIES IN SPACE AND EARTH SCIENCES (ROSES-2017) OPPORTUNITY (NNH17ZDA001N-SAT) UNDER THE STRATEGIC ASTROPHYSICS TECHNOLOGY (SAT) PROGRAM ELEMENT. WITH PREVIOUS NASA SUPPORT MIT HAS DEVELOPED A REVOLUTIONARY TYPE OF LIGHTWEIGHT HIGH EFFICIENCY AND HIGH RESOLUTION DIFFRACTION ELEMENT CALLED A CRITICAL ANGLE X-RAY TRANSMISSION (CAT) GRATING. CONCENTRATED TECHNOLOGY DEVELOPMENT HAS PRODUCED PROTOTYPE GRATING ELEMENTS WITH HIGH DIFFRACTION EFFICIENCY AND SPECTRAL RESOLUTION APPROACHING PREDICTED LEVELS. THIS TECHNOLOGY HAS ADVANCED TO THE POINT WHERE IT WAS SELECTED FOR THE ARCUS X-RAY SPECTROMETER PROPOSAL FOR A NASA MIDEX MISSION WHICH HAS WON A PHASE A AWARD. A SERIES OF PROTOTYPE FLIGHT GRATING SPECTROMETERS USING CAT GRATINGS HAVE BEEN BUILT AND X-RAY TESTED MEETING ARCUS MISSION REQUIREMENTS AND PASSING ENVIRONMENTAL TESTS. HOWEVER THE RELATIVELY MODEST REQUIREMENTS FOR THE ARCUS SPECTROMETER ARE NOT AS CHALLENGING AS WOULD BE NECESSARY FOR A STRATEGIC MISSION SUCH AS LYNX. FURTHER ADVANCES IN GRATING DIFFRACTION EFFICIENCY RESOLUTION ELEMENT SIZE MANUFACTURABILITY AND ASSEMBLY ACCURACY WILL BE NECESSARY IN ORDER TO MEET LYNX SCIENTIFIC AND COST GOALS. MIT PROPOSES TO DEVELOP NEW GRATING FABRICATION TECHNOLOGY LEVERAGING THE ADVANCED SEMICONDUCTOR INDUSTRY TOOLS OF THE MIT LINCOLN LABORATORY SILICON WAFER FOUNDRY ESSENTIALLY TRANSFERRING FABRICATION PROCESSES DEVELOPED BY MIT STUDENTS ON SMALL WAFERS USING RESEARCH TOOLS IN OUR ON-CAMPUS LAB TO THE MORE PRECISE 200 MM WAFER TOOLS IN LINCOLN'S MICROELECTRONICS LABORATORY FACILITY. THE IMPROVED PROCESS CONTROL AND PATTERNING ACCURACY ENABLED BY LINCOLN'S ADVANCED CMOS FABRICATION TOOL SET ARE ESSENTIAL TO ENABLE THE REQUIRED IMPROVEMENTS IN SPECTROMETER PERFORMANCE REQUIRED BY LYNX.