the resistance consists of the following:
1. the substrate material is usually 96% alumina ceramic. the substrate should not only have good electrical insulation, but also have excellent thermal conductivity, electrical properties and mechanical strength at high temperature
2. the resistance film is printed on the ceramic substrate with a certain resistivity paste, and then sintered
3. electrode is to ensure that the resistor has good solderability and reliability, generally using three-layer electrode structure: inner, middle and outer electrode
4. the protective film covers the resistance film mainly to protect the resistance body. on the one hand, it plays a mechanical protection role, on the other hand, it makes the surface of the resistance body have insulation, so as to avoid the fault caused by the contact between the resistance and the adjacent conductor, it can also prevent the resistance film from being eroded by the electrolyte, which is usually glass paste with low melting point.