Microstructure and optical properties of Eu-doped Mg_xZn_(1-x)O hexagonal nanocrystals  

作　　者：LI Na,CUI HaiTao,LIU YuXue,XU ChangShan&LIU YiChun Centre for Advanced Optoelectronic Functional Materials Research,Northeast Normal University,Changchun 130024,China 

出　　处：《Science China(Technological Sciences)》2010年第3期761-765,共5页中国科学（技术科学英文版）

基　　金：supported by the Key Project of the Ministry of Education(Grant No.108045);the National Natural Science Foundation of China(Grant No.10874023);Program for Century Excellent Talents in Universities(Grant No.NCET-08-0757)

摘　　要：Eu-doped MgxZn1-xO hexagonal nanocrystals with wurtzite-type structure were fabricated on quartz substrates by electron beam evaporation using Mg0.15Zn0.85O:Euy(0≤y≤0.08)target combined thermal annealing followed with rapid cooling.The influence of Eu on the microstructure and optical properties of MgxZn1-xO hexagonal nanocrystals had been investigated using X-ray diffraction spectra,X-ray photoelectron energy spectra,scanning electron microscopy,absorption spectra,and photoluminescence spectra.It was found that Eu-doped MgxZn1-xO hexagonal nanocrystals annealed at 700°C exhibited(002)preferred orientation,whereas undoped MgxZn1-xO hexagonal nanocrystals annealed at 700°C did not exhibit preferential growth.The Mg concentration of Eu-doped and undoped MgxZn1-xO hexagonal nanocrystals annealed at 700°C were both 0.08.However,an evident phase separation of the Eu-doped MgxZn1-xO hexagonal nanocrystals with Mg0.08Zn0.92O/Mg0.03Zn0.97O/air SQW core-shell structures was observed.The binding energy of exciton in Mg0.03Zn0.97O(66 meV)was larger than that in Mg0.08Zn0.92O(50 meV)that was further evidence of Mg0.08Zn0.92O/Mg0.03Zn0.97O/air SQW core-shell structures formed.Eu-doped MgxZn1-xO hexagonal nanocrystals with wurtzite-type structure were fabricated on quartz substrates by electron beam evaporation using Mg0.15Zn0.85O:Euy(0≤y≤0.08)target combined thermal annealing followed with rapid cooling.The influence of Eu on the microstructure and optical properties of MgxZn1-xO hexagonal nanocrystals had been investigated using X-ray diffraction spectra,X-ray photoelectron energy spectra,scanning electron microscopy,absorption spectra,and photoluminescence spectra.It was found that Eu-doped MgxZn1-xO hexagonal nanocrystals annealed at 700°C exhibited(002)preferred orientation,whereas undoped MgxZn1-xO hexagonal nanocrystals annealed at 700°C did not exhibit preferential growth.The Mg concentration of Eu-doped and undoped MgxZn1-xO hexagonal nanocrystals annealed at 700°C were both 0.08.However,an evident phase separation of the Eu-doped MgxZn1-xO hexagonal nanocrystals with Mg0.08Zn0.92O/Mg0.03Zn0.97O/air SQW core-shell structures was observed.The binding energy of exciton in Mg0.03Zn0.97O(66 meV)was larger than that in Mg0.08Zn0.92O(50 meV)that was further evidence of Mg0.08Zn0.92O/Mg0.03Zn0.97O/air SQW core-shell structures formed.

关 键 词：MGXZN1-XO HEXAGONAL NANOCRYSTALS europium SEM absorption SPECTRA photoluminescence X-ray PHOTOELECTRON energy SPECTRA 

分 类 号：TB383.1[一般工业技术—材料科学与工程]