Multifunctional materials are a new class of thin films and coatings. These materials show interesting characteristics for application in many scientific areas, in special electronic and photonic technologies. These characteristics include sensitivity for thermal, light, mechanical, chemical and other influences, high resistivity, high electrical isolation and transparence in visible range. Recently it was obtained a new oxide type that combines oxygen, nitrogen and indium: the indium oxynitride. In this work, we study the deposition of indium oxynitride by reactive sputtering for application in photoconductor sensors. The deposition processes were performed in a home build magnetron sputtering system, using a four-inch pure In target, nitrogen and oxygen as process gases. The pressure was kept constant at 10 mtorr and the RF power (13.56 MHz) was constant at 250 W. The photoconductors were made with these thin films. The photoelectric detectors were analyzed by IxV (current versus voltage) analyses. The IxV analysis presented a low leakage current (10-8 A). The photoelectric effect was observed from the difference between the case with emitted light and dark currents. It increased around 140 times, under illumination of a halogen lamp. The Hall Effect measurements indicated that the films were n-type semiconductors. The increase in the oxygen concentration added in the plasma, promoted the change in the character of these thin films from conductor to semiconductor material.

This work shows the study of the optical band gap of indium oxynitride (InNO) and indium nitride (InN) deposited by magnetron reactive sputtering. InNO shows multi-functionality in electrical and photonic applications, transparency in visible range, wide band gap, high resistivity and low leakage current. The deposition processes were performed in a magnetron sputtering system using a four-inches pure In (99.999%) target and nitrogen and oxygen as plasma gases. The pressure was kept constant at 1.33 Pa and the RF power (13.56 MHz) constant at 250 W. Three-inches diameter silicon wafer with 370 micrometer thickness and resistivity in the range of 10 ohm-centimeter was used as substrate. The thin films were analyzed by UV-Vis-NIR reflectance, photoluminescence (PL) and Hall Effect. The band gap was obtained from Tauc analysis of the reflectance spectra and photoluminescence. The band gap was evaluated for both films: for InNO the value was 2.48 eV and for InN, 1.52 eV. The relative quantities obtained from RBS spectra analysis in InNO sample are 48% O, 12% N, 40% In and in InN sample are 8% O, 65% N, 27% In.