| Abstract
| - We show that electron beam evaporation of metal onto a monolayer of organic molecules can yield reproducibleelectrical contacts, if evaporation is indirect and the sample is on a cooled substrate. The metal contact formswithout damaging even the molecules' outermost groups. In contrast, direct evaporation seriously damagesthe molecules. By comparing molecular effects on metal/molecular layer/GaAs junctions, prepared by indirectevaporation and by other soft contacting methods, we confirm experimentally that Au is not an optimal choiceas an evaporated contact metal. We ascribe this to the ease by which Au can diffuse between molecules,something that can, apart from direct contact−substrate connections, lead to undesired and uncontrollableinterfacial interactions. Such phenomena are largely absent with Pd as evaporated contact.
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