The Department of Mechanical Engineering at BZU organizes a lecture entitled: "Printed Nanocomposite Dielectric Gate Insulator for Organic Field Effect Transistors," delivered by Dr. Amjad al-Taweel on 22 March 2011.

ABSTARCT:

Organic Field Effect Transistors (OFETs), whose characteristics are modulated by an electric filed, are a prominent constituent of modern microelectronics.  Since they were first introduced by Tsumura et al. in 1986, they have undergone great progress, especially during the last several years.  OFETs are particularly interesting as their fabrication processes are more cost effective and much less complex compared with conventional silicon technology, In general, low-temperature deposition and solution processing can replace the high-temperature and high-vacuum deposition and sophisticated photolithographic pattering involved in conventional silicon technology.  Additionally, the mechanical flexibility of organic materials makes them compatible with flexible substrates for lightweight and foldable products.

Printed high capacitance nanocomposite dielectric material was demonstrated as a gate insulator for organic field effect transistors (OFETs).  A nanocomposite consisting of cross-linked Propylene Glycol Methyl Ether Acetate and Barium Titanate (BTO) nanoparticles was developed and utilized as the gate insulator. The high permittivity (k=35), bimodal nanocomposite utilized had two different filler particle sizes; 200 nm. and 1000 nm. diameter particles.   Due to the nanosize of the BTO particles, they disperse well in the organic solvent, which makes it possible to use solution-processable methods, such as printing to fabricate the devices.  It was demonstrated that OFETs with the nanocomposite dielectric layer have higher field-induced current than that of conventional devices due to the high dielectric constant of the gate insulator.