Solving the doping asymmetry issue in wide gap semiconductors is a key dificulty and long-standing challenge for device applications.Here,a desorption-tailoring strategy is proposed to juggle the carrier concentration...Solving the doping asymmetry issue in wide gap semiconductors is a key dificulty and long-standing challenge for device applications.Here,a desorption-tailoring strategy is proposed to juggle the carrier concentration and transport.Specific to the p-doping issue in Al-rich AlGaN,self-assembled p-AlGaN superlattices with an average Al composition of over 50%are prepared by adopting this approach.The hole concentration as high as 8.1×10^(18)cm^(-3)is thus realized at room temperature,which is attributed to the signifcant reduction of effective Mg activation energy to 17.5 meV through modulating the activating path,as well as the highlighted Mg surface-incorporation by an intentional interruption for desorption.More importantly,benefting from the constant ultrathin barrier thickness of only three monolayers via this approach,vertical miniband transport of holes is verifed in the p-AlGaN superlattices,greatly satisfying the demand of hole injection in device application.280 nm deep-ultraviolet light emitting diodes are then fabricated as a demo with the desorption-tailored Al-rich p-AlGaN superlattices,which exhibit a great improvement of the carrier injection efficiency and light extraction efficiency,thus leading to a 55.7%increase of the light output power.This study provides a solution for p-type doping of Al-rich AlGaN,and also sheds light on solving the doping asymmetry issue in general for wide-gap semiconductors.展开更多
基金the National Key Research and Development Program of China(Nos.2016YFB0400101,and 2018YFE0125700)the National Natural Science Foundation of China(Nos.61974002,62075081,and 61927806)+1 种基金the Key-Area Research and Development Program of Guangdong Province(No.2020B010172001)the Major Scientific and Technological Innovation Project(MSTIP)of Shandong Province(No.2019JZZY010209).
文摘Solving the doping asymmetry issue in wide gap semiconductors is a key dificulty and long-standing challenge for device applications.Here,a desorption-tailoring strategy is proposed to juggle the carrier concentration and transport.Specific to the p-doping issue in Al-rich AlGaN,self-assembled p-AlGaN superlattices with an average Al composition of over 50%are prepared by adopting this approach.The hole concentration as high as 8.1×10^(18)cm^(-3)is thus realized at room temperature,which is attributed to the signifcant reduction of effective Mg activation energy to 17.5 meV through modulating the activating path,as well as the highlighted Mg surface-incorporation by an intentional interruption for desorption.More importantly,benefting from the constant ultrathin barrier thickness of only three monolayers via this approach,vertical miniband transport of holes is verifed in the p-AlGaN superlattices,greatly satisfying the demand of hole injection in device application.280 nm deep-ultraviolet light emitting diodes are then fabricated as a demo with the desorption-tailored Al-rich p-AlGaN superlattices,which exhibit a great improvement of the carrier injection efficiency and light extraction efficiency,thus leading to a 55.7%increase of the light output power.This study provides a solution for p-type doping of Al-rich AlGaN,and also sheds light on solving the doping asymmetry issue in general for wide-gap semiconductors.
