Organic field-effect transistors were fabricated with pentacene as the active material and different polymeric dielectrics such as cyano-ethylpullulan, poly(4-vinyl phenol), polymethylmethacrylate, parylene-C and polyimide as the gate material. The performance of the devices is compared with respect to the parameters, field-effect mobility, threshold voltage, subthreshold swing, and the maximum possible value of interface traps. (c) 2007 Elsevier Ltd. All rights reserved.