High‐Detectivity InGaAs/GaAsP Superlattice PIN Photodetector with a Thin Absorber on GaAs substrate for 1100 nm Applications
Rémy Tribout, Alexis Palais, Driss Mouloua, Mickael Martin, Frédérique Ducroquet, Sébastien Cavalaglio, Badreddine Smiri, Jeremy Da Fonseca, Jeremy Moeyaert, Clara Cornille, Franck Bassani, Charles Leroux, Veronika Letka, Vita Mergner, David Cooper, Evan Oudot, Christophe Duluard, Sophie Barbet, Christophe Jany, Thierry BaronABSTRACT
III‐V materials exhibit superior optoelectronic properties compared to conventional semiconductors, making them ideal for short‐wavelength infrared (SWIR) photodetectors. These devices are in demand for applications such as telecommunications, LiDAR, and biomedical engineering around 1100 nm wavelength, which is safer for humane eyes, minimally absorbed by the atmosphere, and resistant to ambient light interference. Despite this, semiconductor‐based solutions in this range remain limited. Here, we present a strain‐compensated InGaAs/GaAsP superlattice grown by metal‐organic vapor phase epitaxy on a 100 mm GaAs substrate. High‐quality epitaxy is confirmed by Transmission Electron Microscopy, surface morphology is analyzed by Atomic Force Microscopy, structural properties are characterized using X‐Ray Diffraction, and optical characteristics are assessed via photoluminescence and absorbance. At −1 V bias, the device exhibits a low dark current density of 2.3 × 10 −7 A/cm 2 at room temperature and a high detectivity of 1.9 × 10 11 Jones under 1100 nm excitation, with an external quantum efficiency (EQE) close to expectations. The structural and optoelectronic results demonstrate the potential for producing very thin photodetectors compared to those currently on the market with performances that can be further improved by integrating these photodetectors into resonant cavities.