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The experiments described in this paper look to further transient electronic device development by exploring the fracturing capabilities of aluminum copper (II) oxide and aluminum bismuth (III) oxide nanothermites. In particular, a quick, inexpensive test was developed that was able to characterize the substrate fracturing capability of these selectively deposited energetic materials. Using this test, aluminum bismuth (III) oxide nanothermite with near stoichiometric composition was shown to be an effective mate-rial for fracturing silicon wafers of two different thicknesses for the configuration considered. Nanothermites were deposited at various equivalence ratios, resulting in a range of damage, which enables material preparation in a given practical application to be based on the desired level of resultant fracturing. This data was subsequently compared with thrust measurements and gas shock formation in an effort to correlate thrust production to the severity of fracturing produced.

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With an eye towards improving the safety of the deposition of energetic materials while broadening the scope of materials compatible with inkjet printing, this work demonstrates the use of combinatorial inkjet printing for the deposition of energetic materials. Two largely inert colloidal suspensions of nanoaluminum and nanocopper (II) oxide in dimethylformamide with polyvinylpyrrolidone were sequentially deposited on a substrate using piezoelectric inkjet printing. The materials were deposited in such a way that the aluminum and copper (II) oxide droplets were adjacent, and overlapping, to allow for in situ mixing of the components. The alternating deposition was repeated to create a sample with multiple layers of energetic materials. Energetic performance was subsequently tested on samples printed with 3, 5, and 7 layers of materials using a spark igniter. This ignition event was observed with a high speed camera and compared to representative samples printed with pre-mixed nanothermite. High speed thermal imaging supported a conclusion that the maximum reaction temperature of comparable samples printed with the dual nozzle technique was nominally 200 K less than the samples printed with a single nozzle. Scanning transmission electron microscopy images confirmed a claim that the material constituents were comparably mixed with the single and dual nozzle techniques. This work proves the feasibility of reactive inkjet printing as a means for depositing energetic materials from two largely inert suspensions. In doing so, it opens the doors for safer material handling and the development of a wide array of energetic materials that were previously deemed incompatible with inkjet printing.