The interpretation of space-charge-limited currents in semiconductors and insulators

The specific current-voltage-temperature dependence of space-charge-limited conduction processes in semiconductors and insulators is largely determined by the distribution in energy of traps within the band gap. A linear dependence of current-density on the square of the applied voltage, may be alternatively interpreted in terms of either a single discrete trapping level, or of an exponential trap distribution. The two types of trapping behavior may be distinguished using measurements of the variation of current with temperature for a range of different constant voltages.