Broadband infrared response of sulfur hyperdoped silicon under femtosecond laser irradiation

Broadband infrared response has attracted great attention due to its potential applications in silicon based photodetectors. We have studied broadband infrared response of sulfur hyperdoped silicon under femtosecond laser irradiation. The fabricated PN photodiodes exhibit several photoresponse spectral peaks in near and mid-infrared region of electromagnetic spectrum. The onset energies corresponding to the distinct sub-band gap photoresponse features are consistent with the active energy levels of known sulfur within the silicon band-gap. This technique may offer a promising approach to fabricate low-cost broadband silicon based detectors.