Simultaneous diffusion of Zn and P in InGaAs and GaSb cells for solar and thermophotovoltaic space applications.

In0.53Ga0.47As (InGaAs) heterostructures and GaSb cells with a p/n configuration were developed. These cells can be used as thermophotovoltaic (TPV) converters and as bottom solar cells in high-efficiency tandems with wide gap top cells, respectively. All cells were fabricated by diffusion of Zn and P into undoped layers of InGaAs grown by liquid phase epitaxy (LPE), and into n-GaSb(Te) substrates. The cells had total areas of 1, 0.16, and 0.04 cm(2). The typical one-sun AMO 25 degreesC efficiency, short-circuit current density, open-circuit voltage, and fill factor, of the InGaAs solar cells were 8.2-9.4 %, 45-50.4 mA/cm(2), 0.35-0.36 V and 0.69-0.71, respectively. The InGaAs TPV devices demonstrated open-circuit voltage voltages in the range of 0.42-0.5V and short-circuit current densities of 1.5-31 A/cm(2). The highest fill factor achieved in our cells at 25 degrees C was 0.785 at 15.5 A/ cm(2).