Mechanically flexible low-leakage multilayer gate dielectrics for flexible organic thin film transistors

The incorporation of an ultrathin, atomic layer deposited Hf O2 layer in between the spin-coated poly-4-vinyl phenol (PVP) organic layers in the laminated multilayer gate dielectric for pentacene organic thin film transistors on a flexible substrate reduced the gate leakage current by three to four orders of magnitude and thereby significantly enhanced the current on/off ratio up to 104 -fold. Cyclic bending testing indicated that the electrical characteristics of the device with the PVPHf O2 PVP trilayer gate dielectric stack were superior to those of the device with the single PVP gate dielectrics due to the improved mechanical and electrical stabilities of the gate dielectric.