ISSN:
1089-7550
Quelle:
AIP Digital Archive
Thema:
Physik
Notizen:
We present photoluminescence (PL), UV absorption, electroluminescence and x-ray reflectivity studies of self-assembled multilayer films containing alternate layers of conjugated copolymers, and nonconjugated insulating polymers. We show that the PL emission properties of these organic quantum wells can be "tuned'' by a proper choice of the conjugated copolymer and the thickness of the insulating layers. Particularly, some of the self-assembled ultrathin films containing thin (∼7 A(ring)) insulating polymeric layers exhibit a blue shift upon decreasing the thickness of the assembly. The PL shift is roughly proportional to 1/d2 where d is the thickness of the assembly, as expected for confined photogenerated electron-hole pair in an infinite square potential well. In contrast, the PL emission of similar assemblies but containing thick (∼40 A(ring)) insulating layers is independent of the assembly thickness and exhibit emission in the blue. This may suggest a strong spatial confinement. Light emitting diodes based on self-assembled multilayer films with improved efficiency and stability and with threshold voltage as low as 2.6 V could be fabricated. © 1996 American Institute of Physics.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.361250
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