資源描述:
《zn空位對al-p共摻雜zno電子結(jié)構(gòu)影響的第一性原理計算》由會員上傳分享,免費在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、Zn空位對Al-P共摻雜ZnO電子結(jié)構(gòu)影響的第一性原理計算李磊磊李維學(xué)戴觸王青蘭州理工大學(xué)理學(xué)院蘭州理工大學(xué)省部共建有色金屬先進(jìn)加工與再利用國家重點實驗室摘要:采用第一性原理平面波贗勢法計算ZnO(Al,P)體系的晶格參數(shù)和電子結(jié)構(gòu),重點分析Zn空位對體系晶體結(jié)構(gòu)、形成能、態(tài)密度的影響.計算結(jié)果表明:A1和P共摻雜過程中,AlZn-PZn有更低的形成能,能帶分析呈現(xiàn)n型.并隨著Zn空位濃度的增大使得摻雜后的晶胞體積減小,晶格常數(shù)c先堉大后減小.存在Zn空位的摻雜體系形成能比AlZn-PO摻雜體系低,體系較穩(wěn)定.能帶分析呈現(xiàn)p型趨勢.A1和P以1:2的比例摻雜時,體系的形成能降低
2、,體系更穩(wěn)定;同時,比較1個VZn和2個VZn的Alzn-Pz#摻雜體系的能帶結(jié)構(gòu)發(fā)現(xiàn),隨著Zn空位濃度增大,帶隙增大,體系P型化特征增強.AlZn-2PZn共摻雜體系帶隙減小為0.56eV,更有利于提高其導(dǎo)電性質(zhì).然而出現(xiàn)2VZn后,帶隙增大為0.73eV,小于本征ZnO帶隙,P型化程度更強烈;此外態(tài)密度分析表明2VZn的AlZn-2Pz,、.共摻雜使得態(tài)密度更加分散,更多的電子穿過費米能級使得P型化更明顯.因此,將A1/P按1:2的比例共摻且Zn空位增至2個時,可以獲得導(dǎo)電性能更好的p型ZnO.關(guān)鍵詞:A1-P共摻雜;第一性原理;Zn空位;電子結(jié)構(gòu);作者簡介:李磊磊(199
3、2-),男,碩士研宄生;E-mail:heatj@foxmail.com作者簡介:李維學(xué)(W63-):教授,博士,主要從事半導(dǎo)體材料第一性原理計算仿真研究,E-mail:lwx@lut.cn收稿日期:2016-09-12基金:國家自然科學(xué)基金(50873047)EffectsofZincVacanciesonElectronicStructureofAl-PCo-dopedZnO:First-principlesCalculationsLILeileiLIWeixueDAIJianfengWANGQingSchoolofSciences,LanzhouUniversityofT
4、echnology;StateKeyLaboratoryofAdvancedProcessingandRecyclingofNon-ferrousMetals,LanzhouUniversityofTechnology;Abstract:Withpseudo-potentialplane-wavebasedondensityfunctionaltheory(DFT),effectsofzincvacanciesonZnOlatticeparametersandelectronicstructureofAl-Pco-dopedwerestudied.Formationenergy
5、,densityofstatesareanalysed.TtshowsthatAlZnPZnhasthelowestformationenergyandpresentsn-typeintheprocessofco-doping.Presenceofzincvacanciesmakecellvolumedecrease,andlatticeconstantcincreaseanddecreasesasconcentrationofzincvacanciesincrease.Accordingtoformationenergyofcodoping,formationofzincva
6、canciessystemismorestablethanAlZn-PO.SystemwithA1andPratioof1:2co-dopingcanreduceformationenergyandbecomemorestable.WithcomparisonsofbandstructureofVZnand2VZn,itisfoundthatbandgapincreasedwithzincvacanciesincreasing,whichmakesp-typeZnOmoreobviousandenhancesconductivityofAlZn-2PZnco-dopingsys
7、tems.However,forAlZn-2PZnco-dopingof2VZn,itshowsgreatsuperiorityofp-type.Accordingtostatedensityanalysis,AlZn-2PZnof2VZnmakesthestatedensitymorediffuse,andgothroughtheFermilevel,whichleadstoformationofobviousp-type.Asaresult,betterp-typeZnOcanbeobt