Wavelength – Tunable Grating – Resonance InGaAs Narrowband Photodetector with Infrared Optical PCM, Antimony Triselenide (Sb2Se3)

We proposed a wavelength-tunable grating-resonance narrowband photodetector (PD) array designed to operate at the wavelength range of 1300 nm to 1700 nm. The PD layer with a thin InGaAs absorbing layer is bonded on the Si grating to achieve the optical resonance, and the refractive index-tunable PCM layer, formed by depositing antimony triselenide (Sb
2
Se
3
) on the pixels, allows for wavelength tuning. Through device fabrication and measurement, we successfully demonstrate excellent wavelength selectivity based on the grating period, high responsivity peaks of about 150 mA/W, narrow FWHMs, and distinct peak shifts resulting from the phase change.