NTC Thermistor Manufacturing Process and Quality Control
NTC thermistor starting materials are different oxides of metals such as manganese, iron, cobalt, nickel, copper and zinc,
to which chemically stabilizing oxides may be added to achieve better reproducibility and stability
of the thermistor characteristics.
The oxides are milled to a powdery mass, mixed with a plastic binder and then compressed into the desired shape. The blanks are then sintered at high temperatures (between 1000 ˇăC and 1400 ˇăC) to produce the
polycrystalline thermistor body. Disks are contacted by baking a silver paste onto the flat surfaces. Depending on the application, the thermistors are fitted with leads or tab connectors, coated
or additionally incorporated in different kinds of housing. Finally the thermistors are subjected to a special aging process to ensure high stability of the electrical values.
The major production process for temperature measurement Leaded NTC thermistors is as following: