Study On The PLD Prepared AZO Thin Films And Related Optoelectronic Properties

Compared to other types of transparent conductive oxide (TCO) thin films, AZO (ZnO:Al) and thin films have obvious advantages, for example, inexpensive and relatively low toxic effects, better stability. As a new generation of transparent conductive films, AZO film has the most development potential in very broad application prospects. In this paper, it is found that both substrate temperature and oxygen partial pressure have effects on the film structure, surface morphology, optoelectronic properties of AZO films were deposited on glass slides and ITO substrates by pulsed laser deposition, the results are as the followings:1. AZO thin films deposited on glass slides and ITO coated glass substrates show c-axis preferential oriented growth with excellent crystallinity, when the substrate temperature ranges from200℃to300℃. The c/a ratio of AZO thin films on glass slides decreases, however, that of AZO thin films on ITO coated glass substrates increases with the increase of substrate temperature. AZO thin films deposited on glass slides and ITO coated glass have c-axis preferential oriented growth with excellent crystallinity, when the oxygen partial pressure ranges from0.8Pa to2.0Pa. Both of the c/a ratios of AZO thin films on glass slides and ITO coated glass substrates decreases with the increase of oxygen partial pressure. The roughness of AZO thin films on ITO coated glass is larger than that of AZO thin films on glass slides.2. The averaged transmittance of AZO thin films on glass slides and ITO coated glass substrates in above80%at different substrate temperatures. The ultraviolet absorption edge moved to the long wave and the band gap of AZO film reduces gradually with the increase of oxygen partial pressure from0.2Pa to8.0Pa. The ultraviolet absorption edge moved toward the long wavelength region and the band gap of AZO film reduces gradually with the increase of test temperature.3. AZO films have low resistivity2.5×10-4Ω·cm and high quality factor2.2x10-2Ω-1, when the substrate temperature is200℃, oxygen partial pressure between0.8Pa and2.0Pa. AZO film is sensitive to light, both the reverse bias and forward bias make the current increase significantly, indicating that AZO thin films exhibit good photoelectric response.