Even though efficient near-infrared(NIR)detection is critical for numerous applications,state-of-the-art NIR detectors either suffer from limited capability of detecting incoming photons,i.e.,have poor spectral respon...Even though efficient near-infrared(NIR)detection is critical for numerous applications,state-of-the-art NIR detectors either suffer from limited capability of detecting incoming photons,i.e.,have poor spectral responsivity,or are made of expensive groupⅢ-Ⅴnon-CMOS compatible materials.Here we present a nanoengineered PIN-photodiode made of CMOS-compatible germanium(Ge)that achieves a verified external quantum efficiency(EQE)above 90%over a wide wavelength range(1.2-1.6μm)at zero bias voltage at room temperature.For instance,at 1.55μm,this corresponds to a responsivity of 1.15 A/W.In addition to the excellent spectral responsivity at NIR,the performance at visible and ultraviolet wavelengths remains high(EQE exceeds even 100%below 300 nm)resulting in an exceptionally wide spectral response range.The high performance is achieved by minimizing optical losses using surface nanostructures and electrical losses using both conformal atomic-layer-deposited aluminum oxide surface passivation and dielectric induced electric field-based carrier collection instead of conventional pn-junction.The dark current density of 76μA/cm2 measured at a reverse bias of 5 V is lower than previously reported for Ge photodiodes.The presented results should have an immediate impact on the design and manufacturing of Ge photodiodes and NIR detection in general.展开更多
基金partially funded through the ATTRACT project funded by the European Union’s Horizon 2020 research and innovation programme under grant agreement No.101004462by Business Finland(Project No.RaPtor 687/31/2019)+1 种基金by the Academy of Finland(Project Nos.328482 and 331313)by Tandem Industry Academia funding from the Finnish Research Impact Foundation.
文摘Even though efficient near-infrared(NIR)detection is critical for numerous applications,state-of-the-art NIR detectors either suffer from limited capability of detecting incoming photons,i.e.,have poor spectral responsivity,or are made of expensive groupⅢ-Ⅴnon-CMOS compatible materials.Here we present a nanoengineered PIN-photodiode made of CMOS-compatible germanium(Ge)that achieves a verified external quantum efficiency(EQE)above 90%over a wide wavelength range(1.2-1.6μm)at zero bias voltage at room temperature.For instance,at 1.55μm,this corresponds to a responsivity of 1.15 A/W.In addition to the excellent spectral responsivity at NIR,the performance at visible and ultraviolet wavelengths remains high(EQE exceeds even 100%below 300 nm)resulting in an exceptionally wide spectral response range.The high performance is achieved by minimizing optical losses using surface nanostructures and electrical losses using both conformal atomic-layer-deposited aluminum oxide surface passivation and dielectric induced electric field-based carrier collection instead of conventional pn-junction.The dark current density of 76μA/cm2 measured at a reverse bias of 5 V is lower than previously reported for Ge photodiodes.The presented results should have an immediate impact on the design and manufacturing of Ge photodiodes and NIR detection in general.
