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By using photovoltaic cells under high-intensity laser illumination, much higher photoconversion efficiencies are obtained than under the solar spectrum. We demonstrate a monocrystalline Si based minimodule to convert laser light into electricity using edge-illuminated Si "minicells" based on polysilicon on silicon oxide passivating contacts. Ten fully metallized devices were stacked in series and illuminated from the edge, creating a high-voltage, low-current minimodule that mitigates resistive and Auger-Meitner losses. The minimodule shows a high open-circuit voltage of >5 V when tested under 1-Sun illumination and >7 V at higher illumination intensities when tested with a flash simulator. The fill factor in these minimodules is limited by shunting at low illuminations but reaches a maximum of ∼78% for higher illumination intensities >40 Suns (current density >1200 mA/cm2), indicating that the minimodules are not limited by series resistance up to 40 Suns. Under 1000 nm monochromatic light, we measure efficiencies >40% at > 40 Suns equivalent illumination, showing the potential of passivated contact Si cells for laser power conversion. • c- Si infrared laser power converters utilizing poly- Si/SiO x passivating contacts. • "Minicell" devices are fabricated with simple processing and combined into high-voltage, low-current multijunction. • Modules achieve efficiency >40% for infrared illumination >40 Suns. • Low series resistance is achieved despite only mechanical contacting of individual minicells within module. • Quokka3 simulations predict behavior and inform pathways for improvement. [ABSTRACT FROM AUTHOR]

Direct growth of GaP on Si enables the integration of III–V and Si optoelectronic devices for a wide variety of applications, and has therefore been the subject of much research for many decades. Most of this effort has been directed toward overcoming the two main technical challenges: 1) removing atmospheric oxygen and carbon contamination and 2) establishing the conditions needed for “APD-free” III–V epitaxy ( i.e ., without antiphase domains). We have developed an OMVPE process for APD-free GaP growth on Si which overcomes both challenges by using AsH 3 to clean and prepare the Si surface in situ at a relatively low temperature. This process is based upon a very brief “AsH 3 -cleaning” step which simultaneously removes atmospheric contamination (thereby eliminating the need for Si regrowth) and creates a single-domain As-terminated Si surface. Here we discuss the key process steps using results from a suite of analysis tools. [ABSTRACT FROM AUTHOR]