The minority carrier diffusion length of n-type GaN fdms grown by metalorganic chemical vapor deposition （MOCVD） has been studied by measuring the surface photovoltaic （PV） spectra. It was found that the minority ...The minority carrier diffusion length of n-type GaN fdms grown by metalorganic chemical vapor deposition （MOCVD） has been studied by measuring the surface photovoltaic （PV） spectra. It was found that the minority carrier diffusion length of undoped n-type GaN is considerably larger than that in lightly Si-doped GaN. However, the data suggested that the dislocation and electron concentration appear not to be responsible for the minority cartier diffusion length. It is suggested that Si doping plays an important role in decreasing the minority carrier diffusion length.展开更多
The persistent photoconductivity（PPC） phenomena in n-type GaN Films grown by metalorganic chemical vapor deposition（MOCVD） have been studied. After using some testing and analysis methods, such as the double cryst...The persistent photoconductivity（PPC） phenomena in n-type GaN Films grown by metalorganic chemical vapor deposition（MOCVD） have been studied. After using some testing and analysis methods, such as the double crystal X-ray diffraction（DCXRD）, the photolumineseence（PL） spectra, etc, it is found that the issue which influences PPC in n-type GaN is not relative to the dislocations and yellow band （YB）, and is caused by the doping level of Si most likely.展开更多
Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomer...Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomers.More importantly,the 1,6-dibromo regioisomers could only be separated by preparative HPLC.Herein,we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives.This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs,which yields exclusively the 1,6-regioisomers.Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer,which causes substantial changes on the optoelectronic properties.Moreover,the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm^(2)V^(-1)s^(-1),showcasing their potential as versatile building block towards high-performance n-type organic semiconductors.展开更多
文摘The minority carrier diffusion length of n-type GaN fdms grown by metalorganic chemical vapor deposition （MOCVD） has been studied by measuring the surface photovoltaic （PV） spectra. It was found that the minority carrier diffusion length of undoped n-type GaN is considerably larger than that in lightly Si-doped GaN. However, the data suggested that the dislocation and electron concentration appear not to be responsible for the minority cartier diffusion length. It is suggested that Si doping plays an important role in decreasing the minority carrier diffusion length.
文摘The persistent photoconductivity（PPC） phenomena in n-type GaN Films grown by metalorganic chemical vapor deposition（MOCVD） have been studied. After using some testing and analysis methods, such as the double crystal X-ray diffraction（DCXRD）, the photolumineseence（PL） spectra, etc, it is found that the issue which influences PPC in n-type GaN is not relative to the dislocations and yellow band （YB）, and is caused by the doping level of Si most likely.
基金support from the National Natural Science Foundation of China(Nos.22071007,22020102001,22335002)the National Key R&D Program of China(No.2022YFB3602802)+3 种基金Beijing Natural Science Foundation(No.Z220025)the National Facility for Protein Science in Shanghai,Shanghai Advanced Research Institute,CAS,for providing technical support in X-ray diffraction data collectionthe High-Performance Computing Platform of Peking University for supporting the computational workthe support of BMS Junior Fellow program。
文摘Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomers.More importantly,the 1,6-dibromo regioisomers could only be separated by preparative HPLC.Herein,we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives.This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs,which yields exclusively the 1,6-regioisomers.Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer,which causes substantial changes on the optoelectronic properties.Moreover,the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm^(2)V^(-1)s^(-1),showcasing their potential as versatile building block towards high-performance n-type organic semiconductors.
