Electron transport in metallic dot arrays: Effect of a broad dispersion in the tunnel junction dimensions

We have shown that for a one-dimensional multijunction array with a broad junction length distribution, we can increase the mean threshold voltage V-th for a given maximal tunnel resistance without increasing the scatter of V-th. For two-dimensional arrays we can increase strongly the output of devices which do not behave as open circuits, without any loss on the scatter on V-th, and still increase the latter with respect to a single-island device. The experimental background which justified the calculation will be described, as our model needs the experimental distribution of the island dimensions and junction lengths. Such a result may either show a way to increase the threshold voltages for a given technology, or allow for larger and therefore more controllable dimensions, or even extend the choice of materials. (C) 1998 American Institute of Physics. [S0021-8979(98)05819-8]