Thickness Dependence of the Electrical Properties in NiCr Thin Film Resistors Annealed in a Vacuum Ambient for π - type Attenuator Applications

NiCr thin films prepared on $SiO_2/Si$ substrates at room temperature by magnetron co-sputtering technique and then annealed in a vacuum ambient $(3{\times}10^{-6}\;Torr)\;at\;400^{\circ}C$. The grain size and crystallinity of the films increased with film thickness. The resistivity of the films slightly decreases as the film thickness increases, Temperature coefficient resistance (TCR) exhibits positive values irrespective of film thickness and TCR in the range of 50 to 400 nm thickness shows suitable values for the application of 10 dB in ${\pi}-type$ attenuators.