MANUFACTURING: Nickel film is deposited on ceramic substrate. This is done by electrolytic deposition of nickel in a chemical bath containing hypophosphate. The sheet resistance is controlled by the amount of nickel and Ni-P alloys depositing on substrate.
SPECIFICATIONS:
Ohm values 0.2 ohm/sq. Cm to 10000 ohm/sq. Cm
Tolerances > 2%
Stability 2%
Temperature coefficient of resistance <+200 ppm /0C
Working voltage 300 volts
Working temperature -40 to 1500C
APPLICATIONS: Photolithographic techniques are used to manufacture this type of resistor. Alloy of nickel and chromium in a ratio 80: 20 or 50: 50 are deposited on ceramic substrate by sputtering in vacuum. Then a resistive film pattern of predetermined length and width is etched out with the help of masks. This process is cost-effective for mass production. Very low mass production. Very low temperature coefficient of resistance and stability are attained by adding small quantities of copper, aluminium, or iron.
SPECIFICATIONS:
Ohm range 1 ohm/sq-cm to 5 kilns-ohms/sq-cm
Temperature coefficient of resistance 50 ppm /0C
APPLICATIONS: There are used in semi-precision and precision applications.