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These devices frequently employ a combination of peroxide based explosives as well as nitramines, nitrates, and nitroaromatics. Detection of these explosives can be challenging due to varying chemical composition and the extremely low vapor pressures exhibited by some explosive compounds. No electronic trace detection system currently exists that is capable of continuously monitoring both peroxide based explosives and certain nitrogen based explosives, or their precursors, in the vapor phase. Recently, we developed a thermodynamic sensor that can detect a multitude of explosives in the vapor phase at the parts-per-trillion (ppt) level. The sensors rely on the catalytic decomposition of the explosive and specific oxidation\u2013reduction reactions between the energetic molecule and metal oxide catalyst; i.e. the heat effects associated with catalytic decomposition and redox reactions between the decomposition products and catalyst are measured. Improved sensor response and selectivity were achieved by fabricating free-standing, ultrathin film (1\u00a0\u00b5m thick) microheater sensors for this purpose. The fabrication method used here relies on the interdiffusion mechanics between a copper (Cu) adhesion layer and the palladium (Pd) microheater sensor. A detailed description of the fabrication process to produce a free-standing 1\u00a0\u00b5m thick sensor is presented.<\/jats:p>","DOI":"10.1038\/s41598-021-86077-6","type":"journal-article","created":{"date-parts":[[2021,3,23]],"date-time":"2021-03-23T11:04:44Z","timestamp":1616497484000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Free-standing, thin-film sensors for the trace detection of explosives"],"prefix":"10.1038","volume":"11","author":[{"given":"Peter P.","family":"Ricci","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Otto J.","family":"Gregory","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,3,23]]},"reference":[{"key":"86077_CR1","doi-asserted-by":"publisher","first-page":"35","DOI":"10.1016\/j.trac.2012.09.010","volume":"42","author":"RG Ewing","year":"2013","unstructured":"Ewing, R. 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