人工晶体学报
人工晶體學報
인공정체학보
2009年
5期
1073-1077
,共5页
韦志仁%强勇%彭翔宇%高平%董国义
韋誌仁%彊勇%彭翔宇%高平%董國義
위지인%강용%팽상우%고평%동국의
ZnO%电子陷阱%掺杂%光生电子
ZnO%電子陷阱%摻雜%光生電子
ZnO%전자함정%참잡%광생전자
ZnO%electron trap%co-codoped%photoelectrons
采用气相反应制备了ZnO和ZnO∶Co微晶,并通过热释光研究了材料中的电子陷阱能级(施主能级),采用微波介电谱研究了材料的光生电子瞬态过程.发现纯ZnO热释光谱有两个峰,分别为-183 ℃和-127 ℃,说明存在两个电子陷阱能级;而ZnO∶Co中热释光信号很弱,只有纯ZnO的十分之一.微波介电谱研究表明,由于电子陷阱对导带电子的驰豫作用,纯ZnO材料导带光电子的衰减为一级指数过程,寿命为802 ns.ZnO∶Co微晶体的最大微波介电谱强度低于纯ZnO晶体的五分之一,电子陷阱密度较小,其光生电子快速衰减,过程仅为10~20 ns.结果说明Co掺杂具有明显的抑制电子陷阱能级生成的作用.
採用氣相反應製備瞭ZnO和ZnO∶Co微晶,併通過熱釋光研究瞭材料中的電子陷阱能級(施主能級),採用微波介電譜研究瞭材料的光生電子瞬態過程.髮現純ZnO熱釋光譜有兩箇峰,分彆為-183 ℃和-127 ℃,說明存在兩箇電子陷阱能級;而ZnO∶Co中熱釋光信號很弱,隻有純ZnO的十分之一.微波介電譜研究錶明,由于電子陷阱對導帶電子的馳豫作用,純ZnO材料導帶光電子的衰減為一級指數過程,壽命為802 ns.ZnO∶Co微晶體的最大微波介電譜彊度低于純ZnO晶體的五分之一,電子陷阱密度較小,其光生電子快速衰減,過程僅為10~20 ns.結果說明Co摻雜具有明顯的抑製電子陷阱能級生成的作用.
채용기상반응제비료ZnO화ZnO∶Co미정,병통과열석광연구료재료중적전자함정능급(시주능급),채용미파개전보연구료재료적광생전자순태과정.발현순ZnO열석광보유량개봉,분별위-183 ℃화-127 ℃,설명존재량개전자함정능급;이ZnO∶Co중열석광신호흔약,지유순ZnO적십분지일.미파개전보연구표명,유우전자함정대도대전자적치예작용,순ZnO재료도대광전자적쇠감위일급지수과정,수명위802 ns.ZnO∶Co미정체적최대미파개전보강도저우순ZnO정체적오분지일,전자함정밀도교소,기광생전자쾌속쇠감,과정부위10~20 ns.결과설명Co참잡구유명현적억제전자함정능급생성적작용.
ZnO and ZnO∶Co microcrystal were prepared by gas phase reaction.The electron trap energy level structure (donor level) and the photoelectrons temporal process of materials was investigated by thermo-luminescence microwave and absorption dielectric spectrometry respetively. Two peaks was observed in thermo-luminescence spectra of pure ZnO, one is -183 ℃ and the other is -127 ℃, which shows that two kinds of electron trap energy level produced by the intrinsic defects in ZnO. The thermo-luminescence intensity of ZnO∶Co was only 10% of pure ZnO, which shows that the consistency of electron trap is very less. The microwave absorption dielectric spectrometry shows the temporal process of photoelectrons in conduction band in pure ZnO decayed according to exponential, the lifetime of phase photoelectrons is 802 ns. The reason of long lifetime is relaxation effects of electron trap to conduction band photoelectrons. The microwave absorption dielectric spectrometry relative intensity of ZnO∶Co less than one-fifth of the pure crystal ZnO, that shows the density of electron trap is less in ZnO∶Co minicrystal, so photoelectrons are disappeared quickly, and the decay process of photoelectrons is only 10-20 ns. The results show that Co doped ZnO have obvious effect on restrain the formation of electron trap energy level.