The present work demonstrates the growth of undoped and Al doped ZnO (AZO) thin films by using nonconventional sol-gel method. The structural, morphological, optical, and electrical properties of obtained thin films are studied. X-ray diffraction (XRD) analysis confirms hexagonal wurtzite structures for both undoped and doped thin films. The crystallite size is found between 15 and 30 nm. Scanning electron microscope (SEM) images show that the films have approximately uniform morphologies, consisting in several flower-like aggregates with nanosized multipetals. From the optical properties, it is found that with the increase in the doping concentration, there is a decrease in the absorption coefficient in the visible wavelength range. It is also noticed that the increase in doping concentration causes an increase in bandgap (E g ) and a decrease in extinction coefficient. Urbach energy decreases with increase in the doping concentration. In the Hall effect study, it is observed that the conductivity and carrier concentration increase sharply with increasing the aluminum quantity. The causes and significance of these observations are discussed.

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The present work demonstrates the growth of Zinc oxide (ZnO) thin films from its powder precursor by using non-conventional sol-gel technique. The structural, morphological and optical properties of obtained thin films were studied under different annealing temperatures. X-ray diffraction (XRD) analysis confirmed hexagonal wurtzite structures for both annealed and pristine thin films. The crystallite size was found between 14 and 16 nm. Field Emission Scanning Electron Microscope (FESEM) images showed that the films have approximately uniform morphologies, consisting in several flower-like aggregates with nanosized multi petals. From the optical properties it was found that with the increase in the annealing temperature there is an increase in the absorption coefficient in the visible wavelength range. It was also noticed that the increase in annealing temperature caused a decrease in bandgap (Eg) and increase in Extinction coefficient. Urbach energy decreased with the increase annealing temperature up to 250°C, afterwards the Urbach energy increased with the increase in the annealing temperature. The causes for these observations are discussed.

In this work high density ZnO nanorods were grown on glass substrate by using a two steps method. In the rst step drop-casting method was used for growth of seed layer by taking Zinc Acetate Dihydrate as precursor. In the second step, ZnO nanorods were prepared through Chemical Bath Deposition process on this seed layer by taking Zinc Nitrate as precursor. Field Emission Scanning Electron Microscope study was done to study the morphology of grown ZnO nanorods. From this study the average diameter and length of nanorods were found to be 33 nm and 270 nm respectively. These nanorods are successfully used for second harmonic generation (SHG) of femtosecond laser pulses of central wavelengths like 1000 nm, 1100 nm and 1300 nm. Discussion is given on the signi cance of this result along with its potential application.

In this work high density ZnO nanorods were grown on glass substrate by using a two steps method. In the first step drop-casting method was used for growth of seed layer by taking Zinc Acetate Dihydrate as precursor. In the second step, ZnO nanorods were prepared through Chemical Bath Deposition process on this seed layer by taking Zinc Nitrate as precursor. Field Emission Scanning Electron Microscope study was done to study the morphology of grown ZnO nanorods. From this study the average diameter and length of nanorods were found to be 33 nm and 270 nm respectively. These nanorods are successfully used for second harmonic generation (SHG) of femtosecond laser pulses of central wavelengths like 1000 nm, 1100 nm and 1300 nm. Discussion is given on the significance of this result along with its potential application.