New evidence of the hopping nature of the excess tunnel current in heavily doped silicon p-n diodes at cryogenic temperatures

Abstract

The new experimental data concerning the effect of magnetic field on electric properties of silicon diodes with high doping levels both in the emitter and base (conduction of which at low temperatures is determined by the excess tunnel current) has been analyzed. In addition to previous investigations of the influence of magnetic fields up to 9.4 T on this tunnel current at 4.2 K, now the measurements have been carried out up to 14 T at temperatures lower than the liquid helium temperature. Under these conditions, the transfer to saturation of the diode magnetoresistance was observed, which agrees with the results predicted theoretically for the hopping conduction via impurity centers in high magnetic fields.

Keywords

• p-n diode
• silicon
• heavy doping
• excess tunnel current
• hopping conduction