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The performance of a positive tone resist, PMMA, for sub 100 nm patterning of nano-dots using electron beam lithography is to be studied. This optimization is done on a JEOL JBX-6000 FS System. The various parameters such as beam current, resist thickness, dose and electron energies are optimized. This patterning involves greater control over beam parameters so as to reduce aberrations that might arise due to astigmatism. In this respect, the optimization of the beam current parameters is very important, as a narrower beam will minimize scattering effects. These structures will be particularly significant for the fabrication of quantum dot based devices. Nano-dot arrays of dimensions 70 nm with equal spacings of 70 nm were obtained at 100 pA beam current at 50 KeV for a dose of 170 μC/cm².

This work presents template synthesis of ordered arrays of nickel, cobalt and nickel hexacyanoferrates (NiHCF) with several distinct morphologies such as dots, rods, and tubes. Anodic alumina oxide (AAO) with preferred pore diameters and thickness was fabricated by electrochemical anodization of aluminum used as template. Ni and Co nanostructures inside AAO template were prepared by electrodeposition using galvanostatic method. NiHCF nanostructures were prepared by electrochemical oxidation of Ni using cyclic voltametry (CV) in the presence of hexacyanoferrate ions. The morphology, chemical, and functional properties of prepared nanostructures were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray microscopy (EDAX), and electrochemical methods. The electrocatalytic properties of NiHCF nanorod arrays electrode and their potential for the detection of hydrogen peroxide and biosensing application were demonstrated.

Gallium oxide nanodots of diameter 300 to 220 nm have been grown by SiO₂ assisted thermal evaporation. The formed grayish white crust deposited on the crucible walls was proved to be crystalline Ga₂O₃ through X-ray diffraction and TEM electron diffraction. The morphology of the samples examined by SEM, confirmed the nanodot structure formation of averag diameter 220 ± 30 nm and average density of 1.77×10⁸ cm^-2. The absorption spectra of the Ga₂O₃ suspension in DMF solution revealed two absorption peaks at 329.99nm (3.76 eV) and 338.60 nm (3.67 eV). Photoemission of blue light at room temperature was observed at 410.3 nm with FWHM 56.7 nm under excitation by 330.00 nm. The growth mechanism of the nanodots is explained in terms of liquid-vapor-solid mechanism (LVS). The remaining hard ingot was found to have 16.6 Vicker's hardness. The silicon glass having the value of Vicker's hardness 15 indicates that the ingot material is 10 % harder than that of glass.