Morphology and optical characterization of organic semiconductor microwires based on tetracyanoquinodimethane

Liquid phase deposition starting from solutions of 7,7′,8,8′ Tetracyanoquinodimethane (TCNQ) is used to grow oriented aggregates consisting of submicron-sized width wires. Spectrophotometric analysis shows that the as-deposited films consist of neutral TCNQ and have polarization dependent optical properties. The TCNQ microstructures react when exposed to organic solvent vapours, forming charge-transfer complexes characterized by a gradual and partial reduction of the organic molecules from the neutral to the monovalent ionic state. The morphology of the solution deposited films before and after the vapour treatment is investigated by means of optical microscopy, and Scanning Electron Microscopy (SEM).