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Fabrication, physical modeling and dynamic response of p-type Al-doped SnO x active channel thin film transistors (TFTs) are presented for the potential application of ultra-high definition (UHD) displays. After deposition of Al-doped SnO x active layer using reactive co-sputtering, the channel was treated with plasma fluorination which improve the device performance of high I ON /I OFF ratio of > 10 6 , low subthreshold swing of ∼100 mV/dec and high field-effect mobility (μ FE ) of 4.8 cm 2 V −1 s −1 . To understand the origin of such high performance, physical modeling and numerical simulations were performed using density of state (DOS) model of defects/traps of oxide semiconductor. This model describes the modifications of donor-like tail states and acceptor-like Gaussian defect states due to Al doping on SnO x and fluorine treatment. To evaluate the device performance for UHD large scale displays, the dynamic responses of p-type TFT pixel circuit for various requirements are simulated with physical models. These results suggest that the Al-doped SnO x TFTs are potential candidates for future high-definition displays and many applications in transparent electronics. INDEX TERMS Thin film transistors (TFTs), Al doped SnO x , plasma fluorination, density of states (DOS), dynamic response.

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Magnetite and biopolymer-magnetite nanoparticles coated with polyethylene glycol (PEG) and chitosan have been synthesized. The adsorption of the biopolymers on the magnetite nanoparticles is confirmed using Fourier Transform Infrared (FTIR) Spectroscopy. Atomic Force Microscopy (AFM) imaging revealed magnetite-biopolymer core–shell nanoparticles of typical size range 25–80 nm. We report a novel way of determining the thickness of the biopolymer coating using noncontact AFM imaging. AFM has been used to study the variation of the biopolymer coating thickness as a function of the magnetite core diameter, biopolymer type, and its concentration. The thickness of the chitosan coating varies in the range of 4–11 nm and increases linearly with increase in magnetite core size. PEG coating thickness has similar values as for the chitosan coating.