Room-Temperature Infrared Photoresponse from Ion Beam–Hyperdoped Silicon

Abstract

Room-temperature broadband infrared photoresponse in Si is of great interest for the development of on-chip complementary metal–oxide–semiconductor (CMOS)-compatible photonic platforms. One effective approach to extend the room-temperature photoresponse of Si to the mid-infrared range is the so-called hyperdoping. This consists of introducing deep-level impurities into Si to form an intermediate band within its bandgap enabling a strong intermediate band–mediated infrared photoresponse. Typically, impurity concentrations in excess of the equilibrium solubility limit can be introduced into the Si host either by pulsed laser melting of Si with a gas-phase impurity precursor, by pulsed laser mixing of a thin-film layer of impurities atop the Si surface, or by ion implantation followed by a subsecond annealing step. In this review, a conspectus of the current status of room-temperature infrared photoresponse in hyperdoped Si by ion implantation followed by nanosecond-pulsed laser annealing is provided. The possibilities of achieving room-temperature broadband infrared photoresponse in ion beam–hyperdoped Si with different deep-level impurities are discussed in terms of material fabrication and device performance. The thermal stability of hyperdoped Si with deep-level impurities is addressed with special emphasis on the structural and the optoelectronic material properties. The future perspectives on achieving room-temperature Si-based broadband infrared photodetectors are outlined.