Cross-Linked PVP 게이트 유기 박막트랜지스터

Abstract

The preparation and processing of PVP- gate insulators on the device performance have been studied in the fabrication of organic thin film transistors (OTFTs). One of polyvinyl series, poly-4-vinyl phenol(PVP) was used as a solute and propyleneglycol monomethyl etheracetate(PGMEA) as a solvent in the formation of organic gate solutions. The cross-linking of organic insulators was also attempted by adding the thermosetting material, poly (melamine-co-formaldehyde) as a hardener in the compounds. From the measurements of electrical insulating characteristics of metal-insulator-metal (MIM) samples, PVP-based insulating layers showed lower leakage current according to the increase of concentration of PVP and poly (melamine-co-formaldehyde) to PGMEA in the formation of organic solutions. The PVP(20 wt%) copolymer with composition of 20 wt% PVP to PGMEA and cross-linked PVPs in which 5 wt% and 10 wt% poly (melamine-co-formaldehyde) hardeners had been additionally mixed into PVP(20 wt%) copolymers were used as gate dielectrics in the fabrication of OTFTs, respectively. In our experiments, the maximum field effect mobility of 0.31cm/Vs could be obtained in the 5 wt% cross-linked PVP(20 wt%) device and the highest on/off current ratio of 1.9210 in the 10 wt% cross-linked PVP(20 wt%) device.