Electrical characterization of indium tin oxynitride thin films for infrared sensor application

transparent conductive oxides (TCOs) are one class of materials with wide band gap ($\sim3.1$ eV). These materials have good transparency and conductivity. Indium Tin Oxide (ITO) is a degenerate semiconductor material with high band gap, transparent in the visible range of the solar spectrum and belonging to TCO class. When nitrogen is added to the ITO thin film, it is formed a new semiconductor, ITON (or indium tin oxynitride). The properties and characteristics of this material depend on the nitrogen concentration that is incorporated in its structure. Characteristics such as band gap and resistivity differ if compared to ITO. ITON thin film also has a higher light response. In this work, Indium Tin Oxynitride films were fabricated by evaporation and PECVD techniques and electrical parameters were characterized. Incorporation of nitrogen into the film by plasma annealing with different temperatures $(140 ^{\circ}\mathrm{C}, 200 ^{\circ}\mathrm{C}, 260 ^{\circ}\mathrm{C}$ and $320 ^{\circ}\mathrm{C})$ could improve further the optical and electrical properties of the ITON films and thus making ITON film an ideal transparent and conducting material for opto-electronic applications. Substrates were silicon (75 mm, p-type, 1-10 ohm.cm) and optical three-inch glass wafers with 0.5 mm thickness. The thin films were analyzed with spectral response, IxV (current x voltage) and Hall effect analyses. The main objective of this study is the development of optoelectronic devices. The current versus voltage curve show the response of light. With the spectral response measures it is possible to verify that ITON based devices have higher quantum efficiency for the near infrared region. In conclusion, the ideal would be the application of these materials in sensors that operate in the infrared range.