Abstract
In this thesis, we fabricated flexible OTFT devices with soluble gelatin as gate dielectric and soluble p-type TIPS-pentacene as the semiconductor layer by using solution process. We found that the parameters of blade coating would affect the characteristics of OTFT devices significantly. The best characteristics of OTFT device occur when the TIPS-pentacene thin film is coated along the charge transport channel with a coating speed of 1 mm/sec at a substrate temperature of 70 ℃. Its field effect mobility is up to 1.71 cm2V-1s-1. Based on AFM and XRD, the crystal of TIPS-pentacene grows along the coating direction when the coating speed is 1 mm/sec and the substrate temperature is 70 ℃. The thin film morphology consisted of many plate-like domains with long-range ordering and the crystallinity increases a lot at the same coating speed and substrate temperature. The formation of plate-like domains and the increment of crystallinity are responsible for better OTFT devices characteristics. We have also demonstrated that the anisotropy of the electrical characteristics of the OTFT devices is in match with oriented TIPS-pentacene crystal growth direction. The influence of coating direction on field effect mobilities is also illustrated.