Nickel phosphide film resistor with titanium dioxide layer - formed on sintered alumina substrate reducing scatter of surface resistivity

摘要

An electric resistor with a NiP resistance film has a substrate of sintered Al2O3 and an intermediate layer of polycrystalline TiO2, with a thickness =1 mu m. It is used in integrated circuits, esp. microwave circuits. The TiO2 layer gives a considerable redn. in the scatter in the resistance per square, e.g. for a resistance film with a value of 50ohm/sq., the scatter is 100% on a 2.5 x 2.5cm2 substrate with no TiO2 coating, cf. 50 plus-or-minus 1 0ohm/sq. The TiO2 can be applied easily by pyrolysis of a suitable Ti cpd. on the substrate.