Here,an engineered tunneling layer enhanced photocurrent multiplication through the impact ionization effect was proposed and experimentally demonstrated on the graphene/silic on heterojunction photodetectors.With con...Here,an engineered tunneling layer enhanced photocurrent multiplication through the impact ionization effect was proposed and experimentally demonstrated on the graphene/silic on heterojunction photodetectors.With con sidering the suitable band structure of the insulation material and their special defect states,an atomic layer deposition(ALD)prepared wide-bandgap insulating(WBI)layer of AIN was introduced into the interface of graphene/silicon heterojunction.The promoted tunneling process from this designed structure dem on strated that can effectively help the impact ionization with photogain not only for the regular minority carriers from silicon,but also for the novel hot carries from graphene.As a result,significantly enhanced photocurrent as well as simultaneously decreased dark current about one order were accomplished in this graphene/insulation/silicon(GIS)heterojunction devices with the optimized AIN thickness of〜15 nm compared to the conventional graphene/silicon(GS)devices.Specifically,at the reverse bias of-10 V,a 3.96-A W_1 responsivity with the photogain of~5.8 for the peak response under 850-nm light illumination,and a 1.03-A W_1 responsivity with~3.5 photogain under the 365 nm ultraviolet(UV)illumination were realized,which are even remarkably higher than those in GIS devices with either AI2O3 or the commonly employed SiO2 insulation layers.This work dem on strates a universal strategy to fabricate broad ba nd,low-cost and high-performance photo-detecting devices towards the graphene-silicon optoelectronic integration.展开更多
基金the National Basic Research Program of China(Grant No.2017YFB0404101 and 2018YFB0406700)National Natural Science Foundation of China(Grant No.61505172 and 61675173)+2 种基金Natural Science Foundation of Fujian Province of China(Grant No.2018J01102)Natural Science Foundation of Jiangxi Province of China(20202ACB214008)the Open Fund of the State Key Laboratory of In teg rated Optoelectronics(IOSKL2020KF12).
文摘Here,an engineered tunneling layer enhanced photocurrent multiplication through the impact ionization effect was proposed and experimentally demonstrated on the graphene/silic on heterojunction photodetectors.With con sidering the suitable band structure of the insulation material and their special defect states,an atomic layer deposition(ALD)prepared wide-bandgap insulating(WBI)layer of AIN was introduced into the interface of graphene/silicon heterojunction.The promoted tunneling process from this designed structure dem on strated that can effectively help the impact ionization with photogain not only for the regular minority carriers from silicon,but also for the novel hot carries from graphene.As a result,significantly enhanced photocurrent as well as simultaneously decreased dark current about one order were accomplished in this graphene/insulation/silicon(GIS)heterojunction devices with the optimized AIN thickness of〜15 nm compared to the conventional graphene/silicon(GS)devices.Specifically,at the reverse bias of-10 V,a 3.96-A W_1 responsivity with the photogain of~5.8 for the peak response under 850-nm light illumination,and a 1.03-A W_1 responsivity with~3.5 photogain under the 365 nm ultraviolet(UV)illumination were realized,which are even remarkably higher than those in GIS devices with either AI2O3 or the commonly employed SiO2 insulation layers.This work dem on strates a universal strategy to fabricate broad ba nd,low-cost and high-performance photo-detecting devices towards the graphene-silicon optoelectronic integration.
