A New Type Semiconductor (Critical Temperature Resistor)

A new type semiconductor, which shows an abrupt resistance change of 2–4 orders of magnitude at about 68°C with negative temperature coefficient, has been prepared by sintering a mixture of V 2 O 5 and an acidic oxide (B, Si or P oxide) or a basic oxide (Mg, Ca, Sr or Ba oxide) in a suitable reducing atmosphere. It has been found that there are some optimum conditions of sintering and reducing for obtaining such remarkable characteristics. Life of the samples obtained under suitable conditions is theoretically estimated to be several ten years in air at 200°C. The large temperature coefficient of resistance of this newly developed semiconductor, which is thirty times as large as the magnitude of the usual thermistor, suggests many useful applications.