QUANTUM CONFINEMENT EFFECTS ON THE OPTICAL PROPERTIES OF ION BEAM SPUTTERED NICKEL OXIDE THIN FILMS

2001 ◽  
Vol 15 (02) ◽  
pp. 191-200 ◽  
Author(s):  
M. GHANASHYAM KRISHNA ◽  
A. K. BHATTACHARYA
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Nickel Oxide ◽  
Band Gap ◽  
Quantum Confinement ◽  
Ion Beam ◽  
Confinement Effects ◽  
Oxide Thin Films ◽  
Quantum Confinement Effects ◽  
Nickel Oxide Thin Films

Quantum confinement effects on the optical properties of ion beam sputtered nickel oxide thin films are reported. Thin films with crystallite sizes in the range 9 to 14 nm have been deposited on to fused silica substrates. There is an increase in band gap, from 3.4 to 3.9 eV, and a decrease in refractive index, from 2.4 to 1.6, with decrease in crystallite size, that can be attributed to quantum confinement effects. The effective mass approximation has been used to explain the observed behaviour in band gap variation.

Structural and Optical Properties of Nebulized Nickel Oxide Thin Films

2014 ◽  
Vol 938 ◽  
pp. 103-107
Author(s):  
V. Gowthami ◽  
M. Meenakshi ◽  
N. Anandhan ◽  
Chinnappanadar Sanjeeviraja
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Nickel Oxide ◽  
Band Gap ◽  
X Ray Diffraction ◽  
Oxide Thin Films ◽  
Structural And Optical Properties ◽  
Functional Layer ◽  
X Ray ◽  
Nickel Oxide Thin Films

Nickel oxide has been widely used as material for antiferromagnetic, electrochromic display and functional layer for chemical sensors. Nickel oxide thin films of various molarities were deposited using a simple nebulizer technique and the substrate temperature was fixed at 350C. The effect of the molarity of precursor solution on structural and optical properties was studied using X-ray diffraction (XRD) and UV-Vis-NIR spectrometer techniques respectively. The band gap of the material was confirmed by photoluminescence spectrometer. It is found that increase in the molarity of 10ml volume of the sprayed solution leads to the increasing in film thickness. X-ray diffraction studies indicated cubic structure and the crystallites are preferentially oriented along (1 1 1) plane. It is also found that as the concentration of the solution increases the transmittance decreases, consequently the band-gap energy wanes from 4.0 eV to 3.2 eV.

The effect of the withdrawal speed on properties of nickel oxide thin films

2019 ◽  
Vol 234 (10) ◽  
pp. 647-655
Author(s):  
Zohra Nazir Kayani ◽  
Atiqa Aslam ◽  
Rabia Ishaque ◽  
Syeda Nosheen Zahra ◽  
Hifza Hanif ◽  
...  
Keyword(s):  
Thin Films ◽  
Nickel Oxide ◽  
Band Gap ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Dip Coating ◽  
Oxide Thin Films ◽  
Withdrawal Speed ◽  
Sem Micrograph ◽  
Nickel Oxide Thin Films

Abstract Nickel oxide thin films have been prepared by sol-gel dip-coating technique on glass substrate. It is shown that nickel oxide thin films have poly crystalline nature. Nickel oxide thin films exhibit high transmission (39–85%) in the wavelength range of 400–900 nm, strong absorption between 300 and 400 nm wavelengths and decrease of band gap values are in the range 3.69–3.27 eV with increase of withdrawal speed. High band gap at low withdrawal speed is because of the small average crystallite size, which decreases with increase in withdrawal speed. The SEM micrograph shows cubic crystallites and surface of thin films become dense, smooth and homogeneous with an increase in withdrawal speed. Assessment of nickel oxide deposition conditions provides gateway for effective and cheap solar cells.

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