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In 2019, the Atacama Rover Astrobiology Drilling Studies (ARADS) project field-tested an autonomous rover-mounted robotic drill prototype for a 6-Sol life detection mission to Mars (Icebreaker). ARADS drilled Mars-like materials in the Atacama Desert (Chile), one of the most life-diminished regions on Earth, where mitigating contamination transfer into life-detection instruments becomes critical. Our Contamination Control Strategy and Implementation (CCSI) for the Sample Handling and Transfer System (SHTS) hardware (drill, scoop and funnels) included out-of-simulation protocol testing (out-of-sim) for hardware decontamination and verification during the 6-Sol simulation (in-sim). The most effective five-step decontamination combined safer-to-use sterilants (3%_hydrogen-peroxide-activated 5%_sodium-hypochlorite), and in situ real-time verification by adenosine triphosphate (ATP) and Signs of Life Detector (SOLID) Fluorescence Immunoassay characterization of hardware bioburden and airborne contaminants. The 20- to 40-min protocol enabled a 4-log bioburden reduction down to <0.1 fmoles ATP detection limit (funnels and drill) to 0.2–0.7 fmoles (scoop) of total ATP. The (post-cleaning) hardware background was 0.3 to 1–2 attomoles ATP/cm2 (cleanliness benchmark background values) equivalent to ca. 1–10 colony forming unit (CFU)/cm2. Further, 60–100% of the in-sim hardware background was ≤3–4 bacterial cells/cm2, the threshold limit for Class <7 aseptic operations. Across the six Sols, the flux of airborne contaminants to the drill sites was ∼5 and ∼22 amoles ATP/(cm2·day), accounting for an unexpectedly high Fluorescence Intensity (FI) signal (FI: ∼6000) against aquatic cyanobacteria, but negligible anthropogenic contribution. The SOLID immunoassay also detected microorganisms from multiple habitats across the Atacama Desert (anoxic, alkaline/acidic microenvironments in halite fields, playas, and alluvial fans) in both airborne and post-cleaning hardware background. Final

We report resistance results from carbon nanotube (CNT) vias of widths from 150 to 60 nm for potential application in integrated circuits technology. Selective CNT growth inside the vias with an areal density of 2x10(11)/cm(2) is achieved with a statistical average resistance of 1.7 k Omega with standard deviation between 420 Omega and 7.1 k Omega, and lowest resistance of 150 Omega for 60 nm vias, the lowest reported value for sub-100 nm-CNT vias. Statistical analysis yields a best-case projected value of 295 Omega for a 30 nm via, within one order of magnitude of its copper and tungsten counterparts.

Carbon nanofibers are promising interconnect materials for future military applications. How they behave in the elevated ambient temperature environment of a battle field is studied by performing series of current-induced nanofiber breakdown experiments. In a battlefield, the ambient temperature of electronic equipment is often raised significantly due to use of ammunition, explosion, and/or fire, but integrated circuits (IC) or chips embedded in the equipment should never malfunction. Interconnects are one of the most critical heat-generating elements on a chip, and their operation must be optimized in the context of the interplay between electrical and thermal transport, especially for military applications., See also ADM002187. Presented at the Army Science Conference (26th) Held in Orlando, Florida on 1-4 December 2008. Published in the Proceedings of the Army Science Conference, December 2008. The original document contains color images.