Current-voltage characteristics of Si:As blocked impurity band photodetectors with hopping conductivity (BIB-II)

The current-voltage characteristics of Si:As blocked impurity band (BIB) structures are investigated. The behavior of the dark current in the temperature range 4.2–25 K and in the range of bias voltages −3 to +3 V is analyzed. It is shown that the main features of the I-V characteristics are governed by the thermal-field injection of charge carriers from the contacts to the BIB structure. The details of the I-V characteristics for bias voltages of both polarities are attributed to generation-recombination processes between the conduction band and the impurity band of the N ⁺ photoconductive layer. It is established that the blocking layer can accumulate charge of both signs, influencing the formation of the dark I-V characteristics. Fiz. Tekh. Poluprovodn. 33, 1005–1009 (August 1999)