摘要
A high-performance and broadband heterojunction photodetector has been successfully fabricated.The heterostructure device is based on a uniform and pinhole-free perovskite film constructed on top of a single-crystal germanium layer.The perovskite/germanium photodetector shows enhanced performance and a broad spectrum compared with the single-material-based device.The photon response properties are characterized in detail from the visible to near-infrared spectrum.At an optical fibre communication wavelength of 1550 nm,the heterojunction device exhibits the highest responsivity of 1.4 A/W.The performance is promoted because of an antireflection perovskite coating,the thickness of which is optimized to 150 nm at the telecommunication band.At a visible light wavelength of 680 nm,the device shows outstanding responsivity and detectivity of 228 A/W and 1.6×10^(10) Jones,respectively.These excellent properties arise from the photoconductive gain boost in the heterostructure device.The presented heterojunction photodetector provides a competitive approach for wide-spectrum photodetection from visible to optical communication areas.Based on the distinguished capacity of light detection and harvesting from the visible to near-infrared spectrum,the designed germanium/perovskite heterostructure configuration is believed to provide new building blocks for novel optoelectronic devices.
基金
the National Natural Science Foundation of China(Nos.61874109,51525202,61674140,61574054,51672076,61804177)
the Foundation for Innovative Research Groups of NSFC(Grant 21521063).
