학술논문

Structural origin of gap states in semicrystalline polymers and the implications for charge transport
Document Type
Working Paper
Source
Subject
Condensed Matter - Materials Science
Condensed Matter - Soft Condensed Matter
Language
Abstract
We quantify the degree of disorder in the {\pi}-{\pi} stacking direction of crystallites of a high performing semicrystalline semiconducting polymer with advanced X-ray lineshape analysis. Using first principles calculations, we obtain the density of states of a system of {\pi}-{\pi} stacked polymer chains with increasing amounts of paracrystalline disorder. We find that for an aligned film of PBTTT the paracrystalline disorder is 7.3%. This type of disorder induces a tail of trap states with a breadth of ~100 meV as determined through calculation. This finding agrees with previous device modeling and provides physical justification for the mobility edge model.
Comment: Text and figures are unchanged in the new version of the file. The only modification is the addition of a funding source to the acknowledgments