Substituted silicon phthalocyanine Langmuir-Blodgett film and its possible use in electronic devices

Abstract

This paper summarizes the preparation of Langmuir-Blodgett (LB) films of a substituted silicon phthalocyanine, namely tetra-4- tert.-butyl-phthalocyaninato-silicon dichloride (ttb-PcSiCl 2), and its possible use in electronic devices. We describe how high quality ttb-PcSiCl 2 LB films which exhibit mechanical and thermal stability can be successfully deposited. The aggregation in the floating film is much reduced and the molecules are stacked edge on to the substrate with a preferred orientation perpendicular to the dipping direction. These are two distinct types of possible use for this film in electronic devices whose performance is enhanced by the incorporation of a few monolayers of ttb-PcSiCl 2: (1) the phthalocyanine layers take an “active” part in photovoltaic devices and gas-sensitive structures; (2) the layers play a “passive” role in metal-organic chemical-vapour-deposited (MOCVD) ZnSe/LB film and MOCVD InP/LB film metal insulator/semiconductor structures.