Schottky photodiodes incorporating monolayers formed by adsorption and by the Langmuir-Blodgett technique

The efficiency of Schottky-barrier photodiodes can be much improved by the inclusion of a monolayer of a suitable amphiphilic substance. Such layers have hitherto been formed by the Langmuir-Blodgett technique. In the paper we describe results obtained using monolayers adsorbed from an alkane solvent, and compare them with results obtained using the Langmuir-Blodgett method. It is shown that adsorbed layers lead to superior layers, and also make it possible to use perfluorinated carboxylic acids which have a pKa too low to be applied by the Langmuir-Blodgett technique.