The stability of individual molecules when subjected to electrical stress is of critical importance to molecular electronic device reliability. In this interdisciplinary study, individual cyclopentene molecules are studied on silicon surfaces using ultra-high vacuum (UHV) scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. Part (a) of the figure shows an atomic resolution UHV STM image of a silicon surface decorated with cyclopentene molecules. Using UHV STM, the desorption yield of cyclopentene when subjected to electrical stress was found to be two to three orders of magnitude lower than previous studies performed on aromatic molecules such as benzene. DFT calculations using the geometry depicted in part (b) of the figure provide quantitative insight into the desorption mechanism. Through this improved understanding of desorption of organic molecules from silicon surfaces, enhanced reliability can be intentionally engineered into future silicon-based molecular electronic devices.
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