<title>Light-emitting devices based on sequentially adsorbed layers of poly(p-phenylene vinylene) (PPV) and poly(acrylic acid) (PAA)</title>

Abstract

We have recently reported on the fabrication of organic light emitting devices based on sequentially adsorption layers of a polycationic poly(p-phenylene vinylene) (PPV) precursor and poly(methacrylic acid) (PMA). Here we have fabricated devices with PPV precursor and poly(acrylic acid) (PAA) in an effort to further improve device performance by controlling the nature of the polyanion with which the PPV precursor is assembled. We have seen dramatic differences in device performance by systematically varying the bilayer composition and the total film thickness by controlling the solution parameters and the total number of bilayers deposited. In addition, the conversion temperature has also been shown to strongly influence device characteristics. The current, best performing device has been for a system in which the bilayer thickness is around 60 angstrom, approximately half of which is due to the PPV. From this system we have been able to achieve luminance levels greater than 1000 cd/m2 using an aluminum cathode and an ITO anode. Such high brightness levels from a PPV single slab device with an aluminum top electrode are quite unusual.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.