Hot carrier-based metal-semiconductor photodetectors: from quantum efficiency models to structural innovations

Abstract Hot carrier photodetectors have emerged as a promising technology in modern photonics. They show immense potential for affordable, high-performance photodetection in various applications due to their simple fabrication and extended spectral range through sub-bandgap operation. This review provides a comprehensive analysis of hot carrier photodetectors, elucidating their operation principles based on internal photoemission. By examining the evolution of quantum efficiency models for hot carrier generation and transport, we offer a comparative analysis of recent advances in these models. We also outline various design strategies and emphasize their role in improving the overall device efficiency. The paper concludes with a summary of performance milestones achieved by different hot carrier photodetectors and a discussion on future directions.