Electrical breakdown and recovery in rectifying m | lb | m structures



Metal 1 | C16H33–Q3CNQ LB film | metal 2 structures exhibiting asymmetric, non-linear I/V characteristics have been fabricated using the Langmuir–Blodgett (LB) technique with LB film thicknesses as small as a single monolayer. When such junctions are subjected to low biases, the I/V traces exhibit little or no asymmetry, but as the applied biases increase, so the I/V asymmetry becomes more evident. The largest applied voltages before breakdown are of the order of 1 V, which represents an E-field of order 108 V m−1. This breakdown under high biases increases the junction conductance and the I/V traces become very noisy. More interestingly, it has been observed that after such breakdown it is possible for the junction to recover on reduction of the bias. It is observed that recovery is not always immediate and may require several voltage sweeps. A subsequent increase in bias will cause breakdown at the same bias as the first breakdown, indicating that no permanent damage has been caused.