Metal/TaN (≈5 nm)/Si diode fabricated by DC magnetron sputtering

Metal/ultrathin Tantalum Nitride (TaN)/p-Si (MTS) diodes were fabricated using dc magnetron reactive sputtering to form the ultrathin (≈5 nm) resistive TaN layer. The diode quality factor and barrier height were directly related to the substrate arrangement during sputtering of the ultrathin TaN layer. An effective barrier height of 0.75±0.01 eV and near-unity diode quality factor were observed while the plane of the substrate was perpendicular to that of the target. However, an effective barrier height of 0.78±0.01 eV and a diode quality factor around 1.15±0.02 were seen while the substrate was parallel to the target. Thermal stability of the as-deposited diodes was studied using elevated-temperature treatment with different time intervals at 100°C and 150°C, respectively. Thermal stability of the MTS diodes was also related to the substrate arrangement during sputtering.