For sensitive detection of neutral and charged particles in satellite survey missions, instrumentation for the efficient rejection of EUV, Deep UV and visible flux is needed that also efficiently transmits the particles. At present, commercially available filters offer deep UV rejection, limited particle transmission efficiency, and limited lateral dimensions. The team of MicroXact Inc., Virginia Tech and Old Dominion University (ODU) is proposing to develop a deep UV blocking particle filter for NASA and commercial applications that will combine superior mechanical stability, with efficient UV blocking and high particle transmission efficiency. The proposed filter is based on macroporous silicon with conformal pore wall coating by Atomic Layer Deposition. In Phase I of the project the team will finalize the design of the MPSi structure, will make two iterations in fabrication of the filter prototype and will perform testing of both UV rejection and particle transmission to fully validate the proposed approach. In Phase II the team will optimize the material fabrication, and design and fabricate a packaged UV blocking particle filter that will fully comply with NASA specifications and will perform testing in a relevant environment. The filters developed on this SBIR project will be commercialized in Phase III.