Temperature coefficient of resistance of sintered semiconductors

摘要

Sintered semiconductors of various compositions were described in a previous paper, with special emphasis on sintered materials with zero temperature co-efficient of resistance. The material was described as an electrical network, the resistance of which was composed of the total of the particle resistances and the resistances between the particles called contact resistances. Figure 1 shows a diagrammatic sketch of a sintered material composed of three components and the electrical network which characterizes this material. The material with a. low or practically zero temperature coefficient of resistance was composed of 72% ZrO2, 23% magnesium-silicate (talc) and 5% graphite. It was observed that the graphite particle size greatly affects the resistance of the material and its temperature coefficient, and further it-was found that a slight variation in particle size or a change in the mixing procedure changes the temperature coefficient from plus to minus, as shown in Figure 2.