Abstract
Chapter 3 Fabrication and characterization of
3.7 Conclusion
The Zn1-xAlxO (0≤x≤0.10) thin films were deposited onto fused silica substrate via PLD technique. The XRD and Raman measurement revealed the c-axis oriented
Chapter 3: Fabrication and characterization of pulsed laser deposited Zn1-xAlxO (0≤x≤0.10) thin films.
hexagonal wurtzite phase for all the films. The best crystallinity was observed for x=0.05.
The optical band gap was observed to be tunable with the aluminum content (x) from 3.26 eV to 3.64 eV. The largest band gap was observed in the thin film having Al content of 5wt%. For the higher value of x, the estimated band gap energy was observed to be decreased slightly. The blue shift in the optical band gap with Al content (x) from x=0.00 to x=0.05 was mainly due to the Burstein moss effect arising due to the high n-type doping effect while a slight red shift for higher x value was due to the band gap renormalization effect associated with many body interaction effect. The variation in the linear refractive index with x was marginal in these films. The films exhibited UV and blue emission dominated photoluminescence signal in RTPL spectra. Also, the green emission in the Al doped film was observed to be reduced with the Al concentration in the film due to the reduction in the oxygen defects.
Chapter 3: Fabrication and characterization of pulsed laser deposited Zn1-xAlxO (0≤x≤0.10) thin films.
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