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Titanium oxyhonitride ͑TiN x O y ͒ thin films were deposited on SiO 2 /Si substrates using reactive dc magnetron sputtering and were then annealed at various temperatures in air ambient to incorporate oxygen into the films. The effect of annealing temperature on the structural and electrical properties of the films was investigated. The grain size of the films decreases with increasing annealing temperature. Crystallinity of the films is independent of annealing temperature in air ambient. Resistivity of the films increases remarkably as an annealing temperature increases and temperature coefficience of resistance ͑TCR͒ of the films varies from a positive value to a negative value. The films annealed at 350°C for 30 min exhibited a near-zero TCR value of approximately −5 ppm/K. The decrease of the grain size with increasing annealing temperature was attributed to an increase of oxygen concentration incorporated into the films during annealing treatment.Thin-film resistors of copper-nickel ͑CuNi͒, 1,2 nichrome ͑NiCr͒, 3,4 and tantalum nitride ͑Ta 2 N͒, 5,6 were commonly used for microelectronics, portable terminal ⌸-type attenuators, and telecommunication devices. Especially, for the reliability of the resistors in ⌸-type attenuators, films are required to have an adequate specific resistivity and a near-zero TCR. A near-zero temperature coefficience of resistance ͑TCR͒ means that the materials show a constant electric resistance over a wide range of temperatures. However, materials such as CuNi, NiCr, and Ta 2 N have a drawback, i.e., their rather low resistivity. 7-9 Hence, these materials are not suitable for the applications ͑in 30 dB of ⌸-type attenuators͒ where a high resistivity is required. We studied tantalum nitride and titanium nitride thin films with an excessive nitrogen concentration to achieve a high resistivity. These materials were satisfactory in the case of resistivity, but the TCR is seen to be highly negative. 10 For this reason, development of the materials to achieve high resistivity and a nearzero TCR is actually a challenge. In this work, we developed the TiN x O y materials with both a high resistivity and a near-zero TCR for 30 dB of ⌸-type attenuator. For 30 dB applications of ⌸-type attenuator, sheet resistance of the titanium oxy-nitride films should be at least 600 ⍀/ᮀ and the TCR should be in the range of −100 to 100 ppm/K. An optimum sheet resistance and a TCR can be realized by controlling the annealing temperature in an air ambient.In this study, titanium oxynitride thin films were prepared on oxidized silicon substrates at room temperature and were then annealed at various temperatures in air ambient. The heat treatment in air ambient was performed for oxygen incorporation into the TiN films for the film resistivity suitable to 30 dB applications of ⌸-type attenuator. The structural and electrical properties including composition, phase structure, resistivity, and TCR are characterized as a function of annealing temperature. ExperimentalTitanium oxynitride thin films about 300 n...

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