Method and means for measuring moisture content of hermetic semiconductor devices

摘要

The moisture content of a hermetically sealed semiconductor device is a function of the dew point of the cavity atmosphere which is the temperature of maximum surface conductivity. A pattern of interdigitated thin film aluminum conductors is provided on an impurity free, non-porous silicon oxide insulative substrate. The surface conductivity of this structure rises as moisture condenses onto and between the conductors as the temperature is reduced at a slow controlled rate to the dew point temperature. The amplitude of the maximum surface conductivity is proportional to ionic impurity concentration.