Hole-injection from a polar mono-molecular layer derivatised ultra-thin gold electrode into a triphenylamine derivative

It is shown, via current-voltage analysis, that modifying the surface of an ultra-thin gold electrode with a self-assembled thiolate polar monolayer is an effective means of circumventing the well documented abrupt negative vacuum level shift, which forms when the amorphous molecular semiconductor N,N′-bis(3-methylphenyl)-N,N′diphenyl-1,1′biphenyl-4,4′-diamine (TPD) is thermally deposited onto gold electrodes.