Charge Carrier Mobility Of Devices Research Articles

The effect of side-chain length on the microstructure and processing window of zone-cast naphthalene-based bispentalenes

The solubilizing side-groups of solution-processable π-conjugated organic semiconductors affect both the crystal structure and microstructure of the respective thin films and thus charge-carrier mobility in devices.

Oligothiophenes in organic thin film transistors – Morphology, stability and temperature operation

We have investigated a series of oligothiophenes in organic thin film transistors (TFTs), with special emphasis on their thin film morphology related to device performance and application requirements. The transistor performance was studied for devices fabricated at different substrate temperatures during semiconductor deposition (ranging from room temperature to 120 °C). A significant dependence of thin film morphology on the substrate temperature was observed, whereas the charge carrier mobility in devices occurs almost unaffected. We have tested the long-term stability of 78 transistor devices (shelf-life in ambient conditions) over a period up to 100 days. Only a small degradation in mobility by less than one order of magnitude was observed. Investigations at elevated temperatures during TFT operation (room temperature to 105 °C) show that devices with α,α′-hexylsexithiophene (Hex-6T-Hex) degrade in their charge carrier mobility by a factor of 8, but completely recover to their initial value of 0.7 cm 2/Vs after a short period of storage at room temperature in ambient conditions.

Performance of poly(3-hexylthiophene) organic field-effect transistors on cross-linked poly(4-vinyl phenol) dielectric layer and solvent effects

Bottom-contact organic field-effect transistors (OFETs) were fabricated using a polymer gate insulator cross-linked poly(4-vinyl phenol) with regioregular poly(3-hexylthiophene) (RR-P3HT) as an active layer from different organic solvents. With this polymer dielectric, a field-effect mobility of 0.084±0.006cm2V−1s−1 was obtained. Solvents and interfacial properties have pronounced effects in determining the crystallinity and device performance of RR-P3HT on the polymer gate layer. Morphology correlation with the charge carrier mobility of RR-P3HT OFETs is investigated. Large nanoscale crystalline island densities of this polymer play an important role in the high charge carrier mobility of devices.