METHOD FOR PRODUCING A SEMICONDUCTOR CERAMIC MATERIAL, SEMICONDUCTOR CERAMIC MATERIAL AND A SEMICONDUCTOR COMPONENT

摘要

The invention relates to a method for producing a semiconductor ceramic material having a non-linear electrical resistance with a positive temperature coefficient, in which a precursor mass that comprises a donor-doped, ferroelectric material having a Perovskite structure and the general formula AxByO3 is sintered in a reduced atmosphere at temperatures of not more than 1200 °C. According to the invention, the sintered material has an average grain size in the sub-micrometer range. The sintered material is then reoxidized at its grain boundaries at temperatures of not more than 600 °C. The grain size of the precursor mass has an average primary grain size in the sub-micrometer range, preferably an average primary grain size of not more than 50 nm, more preferably of not more than 20 nm and even more preferably of not more than 10 nm. The semiconductor ceramic material produced by said method has also an average grain size in the sub-micrometer range, preferably in such a way that 80% of the grains are smaller than 800 nm, more preferably smaller than 300 nm and even more preferably smaller than 200 nm.