Germanium (Ge) quantum dot (QD) photodetectors (PDs) were fabricated on Ge substrates exhibiting a broadband, visible to near-infrared (near-IR) photoresponse in the k ¼ 400-1550 nm range. Room-temperature responsivities (R sp) up to 1.12 A/W and internal quantum efficiency IQE ¼ 313% were obtained, superior to conventional silicon and germanium photodiodes. Noise analysis was performed at visible k ¼ 640 nm and telecom k ¼ 1550 nm wavelengths, both yielding room-temperature specific detectivity D* ' 2 Â 10 10 cm Hz 1/2 W À1. Lowering the operating temperature and incident power led to sharply enhanced performance, with D * ¼ 1.1 Â 10 12 cm Hz 1/2 W À1 and IQE ¼ 1000% at T ¼ 100 K for an incident power of 10 nW at k ¼ 1550 nm. Based on their simple fabrication and silicon technology compatibility, these Ge QD PDs represent a promising alternative for broadband, high-performance visible to near-IR detection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.