Reactive Sputtering of NiCr Resistors With Closely AdjustableTemperature Coefficient of Resistance

[摘要] A process is described to obtain NiCr resistors with adjustable temperature coefficient of resistance (TCR) byreactive sputtering in an Ar-atmosphere with a small amount of oxygen in the range of 2% to 6%. As deposited thefilms show a TCR < −200 ppm/K. By heat treatment in air at a temperature of 350°C the TCR can be raised tovalues above −20 ppm/K. The time of heat treatment necessary to obtain a given TCR depends on the oxygen/argonratio during sputtering. The long term stability is not affected by the choice of this ratio in a wide range.Resistor networks with a solderable conductor pattern of TiPdAu have a TCR of 0±7 ppm/K and a long termresistance drift ≤ 2‰ in the first 1,000 hours at 125°C.

[学科分类] 工程和技术（综合）