In this communication we report on studies of the electroluminescent (EL), optical and electrical properties of In-doped Zinc oxide (ZnO:In) films depending on the deposition parameters. ZnO:In films were prepared by, developed in our laboratory, reactive pulsed laser deposition method.
The experiments were carried out using a laboratory technological unit based on Nd:YAG laser. We used quasi-closed reaction chamber, which was specially constructed for the reactive pulse laser sputtering in oxygen ambient. The ZnO:In thin films were deposited on various substrates in a wide range of temperatures at different values of oxygen pressure.
Analysis of experimental results shows that ZnO and ZnO:In thin films can be deposited in situ by pulsed laser sputtering of synthesized homogeneous targets or of pure metallic targets in high pressure of oxygen at suitable values of substrate temperatures.
We found that the characteristics of the grown films are strongly depend on substrate temperature. Moreover, it was established, that EL and optical properties of films, grown at optimal substrate temperature, can be improved by increasing the oxygen pressure. The performed studies showed that the molar fraction of doping atoms introduced into the host film material is the most important factor for achieving maximum intensity of luminescent emission.
As a result, we prepared the ZnO:In films at optimal deposition conditions, which demonstrated excellent optical parameters in the visible region of the spectrum, good electrical characteristics and strong luminescent emission, with maximum intensity located at 520 nm. The films the optical transmittance higher than 85% and the electrical resistivity up to `104` - `105` Ohm*cm.
Finally, the correlation between the luminescent properties of ZnO:In films and the parameters of the deposition process were determined and compared with their electrical and optical characteristics as well as with their structural parameters.