Inter-band current enhancement by dopant-atoms in low-dimensional pn tunnel diodes

Abstract

Inter-band tunneling current is an attractive transport mechanism for future generations of electronics. However, this mechanism is limited by the momentum conservation law which requires phonon assistance in tunneling due to the indirect-bandgap nature of Si. Here, we show that in low-dimensional pn Esaki diodes, inter-band tunneling current can be enhanced by the resonance of discrete dopants with deepened energy levels. Current enhancement is comparable with the background direct inter-band tunneling and can be modulated by the applied biases, suggesting a pathway for controlling atomic-level resonances for practical purposes.