Molecular Orientation Analysis of a C₈-BTBT Thin Film Grown under an External Temperature Gradient

Abstract

Organic semiconductors with a high carrier mobility can be realized by controlling a growth direction of the thin film. A new method to control the growth direction is using a temperature gradient. Molecular orientation strongly influences on the carrier mobility. Therefore, the molecular orientation of 2,7-dioctyl benzothieno benzothiophene (C₈-BTBT) thin films grown under a temperature gradient, has been evaluated by X-ray absorption fine structure measurements. It is considered that the C₈-BTBT has a molecular orientation with standing up on the substrate, and is aligned to the temperature gradient direction. [DOI: 10.1380/ejssnt.2018.79]