Organic Field-Effect Transistor Devices Based on Latent Pigments of Unsubstituted Diketopyrrolopyrrole or Quinacridone

Abstract
Organic field-effect transistors (FETs) based on unsubstituted diketopyrrolopyrrole (DPP) or quinacridone (QA) have been fabricated using their solvent-soluble precursors called latent pigments (t-BOC DPP and t-BOC QA) which can also be regenerated into their parent pigments by heating at about 200 °C. The use of latent pigments enables us to fabricate FETs by spin coating, offering a low-cost fabrication process rather than an expensive vacuum technology. The objective of the present investigation is to evaluate the performance of DPP- and QA-based FETs prepared using latent pigments. As a result, field effect mobilities of about 7.19×10-6 and 8.23×10-6 cm2 V-1 s-1 are obtained for FETs based on t-BOC DPP and QA, respectively. These values are almost equivalent to those of FETs prepared by the vacuum deposition of DPP and QA, namely 1.43×10-5 and 1.08×10-5 cm2 V-1 s-1, respectively. The present result leads us to conclude that latent pigment technology is an excellent low-cost process fabricating organic FETs