Annealed high band gap tunnel junctions with peak current densities above 800 A/cm2

The development of high-performance high band gap tunnel junctions is critical for producing efficient multijunction photovoltaic cells that can operate at high solar concentrations. The n-InGaP/GaAs/p-AlGaAs TJ has been demonstrated to produce peak tunneling currents (J
_pk
) above 1000 A/cm
²
with minimal absorption losses due to the use of thin (≤50 Å) GaAs layer. We will report on the growth and device modeling of these structures as well as the effect of high temperature annealing on J
_pk
. A method to grow TJ structures resistant to annealing will be described, which has resulted in thermally annealed TJ with J
_pk
above 800 A/cm
²
. This is the highest value ever reported for an annealed high band gap TJ. Device modeling has been used to investigate the source of the high tunneling current, as well as the behavior of the annealed TJ.