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This paper demonstrates the novel application of d.c. sputtered zinc oxide (ZnO) as a charge trapping dielectric material for the application of an organic thin film transistor (OTFT) based non-volatile memory (NVM). The motivation of using ZnO as a dielectric is due to its chemical stability and optical transparency, enabling future development of transparent electronic devices. Unbalanced magnetron d.c. sputtering with Ar:O"2 ratio of 80:20 was used to obtained a ZnO dielectric of 50nm thick. The ZnO has an optical band gap of 3.23eV, resistivity and k-value of 5x10^7@W-cm and 50, respectively. The ZnO sandwiched between two layers of low-k methyl-silsesquioxane (MSQ) sol-gel dielectric creates a triple layer dielectric structure for charge storage. A solution-processable pentacene, 13,6-N-Sulfinylacetamodipentacene, was used as an active layer of an OTFT-NVM. It has been successfully demonstrated that this OTFT-NVM can be electrically programmed and erased at a low voltage.

Most functionalized thiophenes are difficult to electropolymerize due to nucleophilicity that will attack the radical cation inhibiting polymerization. However, we have successfully electrodeposited a newly synthesized functionalized terthiophene monomer 3-((2′:2″,5″:2‴-terthiophene)-3″-yl) acrylic acid (TAA) as an active layer of a organic field-effect transistor (OFET). The polymer was then oxidized in order to increase its conductivity. Various oxidizing potentials were experimented and their effect on the OFET's charge mobility was examined. A mobility of 0.25 cm2 (V s)−1 is achieved with an oxidizing potential of 0.9 V after vacuum drying.

This paper discusses the effect of forming gas (93%N2 + 7%H2) plasma treatment for sol-gel methyl-silsesquioxane (MSQ) as a dielectric film towards the grain morphology of a solution processable pentacene. Atomic force microscopy and X-ray diffractometer results confirm that a brief (10 s) plasma treatment for MSQ increases the grain size of pentacene and encourages its growth in thin-film phase. This paper also demonstrates that the presence of large Si(CH3)3 bonds on the MSQ surface are very important to encourage the growth of pentacene’s molecules in thin-film phase. In addition, this paper also suggests that there is no strong relationship between the grain size and ordering of pentacene molecules.

Polyaniline (PANI) nanotubes configured as a field effect transistor (FET) exhibits a p–n junction diode behavior. The forward-bias current can be modulated by a gate voltage; turning on at negative gate voltage and turning off at positive gate voltage. An energy band diagram model has been proposed to explain the rectifying effect of the PANI nanotubes FET (PNT-FET). All the four different forward bias conduction mechanisms of a typical p–n junction diode can be identified for this PNT-FET using a semi-log graph to confirm this resemblance.