MIM tunnel junctions

The most extensively used theoretical method for the understanding of the MIM tunneling junction is the time-dependent perturbation approach developed by Bardeen (1960). It is sufficiently simple for treating many realistic cases, and has been successfully used for describing a wide variety of effects (Duke, 1969 Kirtley, 1982). 

The detection of photon- or chemically induced electronic excitation became possible with metal-insulator-metal (MIM) tunnel junctions as well as with Schottky devices. In this case, excited carriers are detected that have enongh energy to overcome either a tunnel or a Schottky barrier. Therefore, the metal film acts as a substrate for the reaction, as a photon-adsorbing layer, and as an emitter of hot carriers. There have been many experimental attempts to elucidate the nature of hot carriers using the MIM junction structure [1, 36 6]. It was found that hot electrons injected in MIM structures influence the surface reactivity [47-49]. 

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