Si–InAs heterojunction Esaki tunnel diodes with high current densities

Abstract

Si-InAs heterojunction p-n diodes were fabricated by growing InAs nanowires in oxide mask openings on silicon substrates. At substrate doping concentrations of 1 x 10(16) and 1 x 10(19) cm(-3), conventional diode characteristics were obtained, from which a valence band offset between Si and InAs of 130 meV was extracted. For a substrate doping of 4 x 10(19) cm(-3), heterojunction tunnel diode characteristics were obtained showing current densities in the range of 50 kA/cm(2) at 0.5 V reverse bias. In addition, in situ doping of the InAs wires was performed using disilane to further boost the tunnel currents up to 100 kA/cm(2) at 0.5 V reverse bias for the highest doping ratios. (C) 2010 American Institute of Physics. [doi:10.1063/1.3499365]