Strain engineered < Si/Si_0.97C_0.03 > superlattice photodetector for optoelectronic applications: a comprehensive numerical analysis and experimental verification

In this paper, a strain-modified Si/Si_0.97C_0.03 asymmetrical superlattice exotic type (p + -i-p-n +) avalanche photodetector has been designed for applications on the infrared wavelength region. The photoelectric characteristics of the device are studied by developing a self-consistent quantum phenomena-based drift–diffusion model in conjunction with PSpice simulator. The overall performance of the device has been boosted significantly by introducing strain engineering which enhances the out-plane mobility of the charge particles in the intrinsic/active region of the device. The strain is produced in the intrinsic/active region by inclusion of small amount of carbon (C) into the pure Si material. The proposed strain-modified exotic avalanche photodetector exhibits better performance in terms of quantum efficiency (0.671) and photo-responsivity (0.645 A/W) compared to its planer unstrained Si counterpart (quantum efficiency: 0.481, photo-responsivity: 0.524A/W) at 1800 nm wavelength. Additionally, a 3 × 4 array of photodetectors has been designed using this device and its optoelectronic properties are studied in the IR wavelength region. The superiority of the performance of the 3 × 4 array of photodetectors is established in terms of better quantum efficiency (0.872) and better photo-responsivity (0.851 A/W). The validity of quantum phenomena-based drift–diffusion model is established by comparing the simulated data with experimental findings under similar operating conditions. The developed device can be used in defense as well as biomedical industries for sensing applications.