Micro-transfer printing of antimonide III–V photovoltaics

We demonstrate micro-transfer printing of AlGaAsSb membranes and GaSb-based photovoltaic devices using a lattice-matched design and a citric-acid-based chemistry. Using near-IR microscopy, we quantify the lateral undercut rate of AlGaAsSb membranes. We characterize the performance of GaSb photovoltaics integrated on silicon with a print adhesive with both dark current–voltage characteristics and power conversion efficiency measurements under a 1550 nm laser. The highest performing transfer printed photovoltaic device exhibited 19.1% efficiency under 0.1 W/cm2 and a peak efficiency of 23.8% under 0.86 W/cm2. We evaluate the current–voltage characteristics to identify methods to improve the series resistance of the devices. We also show that the SiNx encapsulation is critical to achieving high power conversion efficiency after selective etching and transfer printing.