Effect of Oxygen Pressure on Growth of Cd0.05Zn0.95O Thin Films Using Pulsed Laser Deposition
In this work, ternary CdxZn1−xO (x = 0.05) thin films were deposited on Corning glass substrates using pulsed laser deposition (PLD) growth technique. Films were grown in environment of oxygen flown into the PLD chamber at pressures of 5, 20 and 40 mTorr. XRD studies revealed wurtzite crystal structure and a highly (002)-preferred orientation for all films. The influence of oxygen pressure on FWHM and lattice constants was recorded. UV-Vis transmittance studies indicated that carrier concentration resulting from the oxygen vacancies in films strongly affects band gap energy. This was confirmed by evaluating carrier concentrations and electrical resistivities of films using a four-probe Hall effect measurement set-up at 298 K. Films grown in 20 mTorr oxygen pressure reported the highest carrier concentration of 1.57 × 1015 cm−2, while registering the lowest energy band gap of 3.2 eV, hence making it a critically important pressure for film growth.
S. Sharma is thankful to UGC, New Delhi for providing financial support through the award of Senior Research Fellowship.
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