Direct observation by resonant tunneling of the B^+ level in a delta-doped silicon barrier

TL;DR

This paper reports direct observation of the B^+ energy level in delta-doped silicon barriers through resonant tunneling, revealing its diamagnetic shift, which provides new insights into impurity states in silicon devices.

Contribution

It introduces a method to directly observe the B^+ level in silicon via resonant tunneling, highlighting the diamagnetic shift in a field-independent reference.

Findings

Resonance in conductance attributed to B^+ tunneling

Direct measurement of diamagnetic shift of B^+ level

Contrasts with magneto-optical spectroscopy results

Abstract

We observe a resonance in the conductance of silicon tunneling devices with a delta-doped barrier. The position of the resonance indicates that it arises from tunneling through the B^+ state of the boron atoms of the delta-layer. Since the emitter Fermi level in our devices is a field-independent reference energy, we are able to directly observe the diamagnetic shift of the B^+ level. This is contrary to the situation in magneto-optical spectroscopy, where the shift is absorbed in the measured ionization energy.