Temperature-dependent characteristics of n-channel transistors based on 5,5′-bithiazolidinylidene-2,4,2′,4′-tetrathiones†
The crystal structures and temperature-dependent transistor properties of newly prepared pentyl and hexyl derivatives of the title compounds are investigated. Similarly to the propyl derivative, the pentyl derivative makes air-stable n-channel transistors in the form of evaporated films as well as single crystals, and the large as-grown single crystals obtained by solvent-vapor annealing show mobilities exceeding 1 cm2 V−1 s−1. The mobility in the intercolumnar direction is comparable to the columnar direction, reflecting the two-dimensional S–S network and transfer integrals. The sharp rise of the transfer curve is maintained down to low temperatures, indicating the absence of deep traps and a comparatively small number of total traps.