Ambient-atmosphere annealing effect on the carrier conduction behavior based on the linear-regime transfer characteristics of pentacene thin film transistors

The linear-regime transfer properties of the annealed pentacene-based organic thin film transistors (OTFTs) in air at various temperatures up to 375K are examined. It is found that the linear-regime carrier mobility increases with increasing annealing temperature reaching a maximum at 350K, and then decreases with further increasing of annealing temperature beyond that point. However, an increase in annealing temperature leads to the shift of the threshold voltage towards positive gate-source voltages. An analysis through the temperature-dependent transfer characteristics of OTFTs reveals that the increased carrier mobility is the result of the reduced values of the hopping distance and the barrier height for hopping. [Display omitted] •The thermal annealing effect on carrier transports in pentacene is researched.•The linear-regime carrier mobility is increased by thermal annealing at 350K.•The temperature-dependent transfer characteristics exhibit the hopping behavior.•Annealing leads to a change in the hopping conduction behavior.•Annealing leads to the reduced values of hopping distance and barrier height.