金属-半导体接触势垒高度的理论计算X

-X(,,361005)2003203211,2003205217:2,TersoffMonch,Tersoff,2:;;:O47115:A:100023819(2003)042412204TheoreticalCalculationofBarrierHeightofMetal-semiconductorContactsLIShupingWANGRenzhiCAIShuhui(Dept.ofPhys.,XiamenUniv.,Xiamen,361005,CHN)Abstract:Takentheaverage2bond2energyasthereferencelevel,tenbarrierheightsofmet2al2semiconductorcontactsarecalculated.Thecoincidentdegreeofourcalculationalvaluesandexperimentalvaluesisnotlessthanthatofcharge2neutralitypointmethod,adoptedbyTersoffandMonch.Itshowsthattheaverage2bond2energymethod,similartoTersoffscharge2neu2tralitypointmethod,canbeusedasoneofthemethodsintheoreticalcalculationofmetal2semi2conductorcontacts.Keywords:barrierheight;average-bond-energymethod;FermilevelPACC:3120A;7115A;7125122,(Schottky),2[1][4],2,Em2,221(a)(b)Schottky[3]Bardeen[4]mVs234200311RESEARCH&PROGRESSOFSSEVol.23,No.4Nov.,2003XE2mail:[e-mail]:(Y07010),EmFEsF,EcEvEg,EsF,BnBp:Bn=Ec-EsF(1a)Bp=EsF-Ev(1b)1(a)Schottky;(b)Bardeen,CowlyandSzeFig.1(a)ThemodelofSchottky;(b)ThemodelofBardeen,CowlyandSze,Bn+Bp=Ec-EvEg1(a)Schottky,Bn=m-Vs,Bnm,SchottkyBnBpm,SchottkyBardeen,Schottky,,SchottkyCowleySze[4]Bardeen,QmQssQsc(Qm+Qss+Qsc=0),,1(b),,,sp3(Eh)(EB)[5](ED)(Em)[1]EsF,(1a)Ec-EsFBn,EhEBEDEm()()(),,22,Qsc=0,1(b)22EcEvEsF,,EsF,,22Fig.2Themodelofbarrierheightofmetal2semicon2ductorcontact32Tersoff[5]23144:2,(MIGS)EB,Tersoff,LAPWEn(k),En(k):G(R,E)=d3rn,k73nk(r)7nk(r+R)E-En(k)=n,keikRE-En(k)(2),k,n,R,7nkEn(k)Tersoff,En(k),(2)G(R,E)=0EBTersoffEB,EsF=EB,(1b)Bp:Bp=EB-Ev(3)Tersoff[5](Ev=0),(3)Bp=EBMonch[6]Tersoff[5],EbpWdg,Bp:Ebp-Ev=0.449Wdg-[Ev-Ev(kmv)](4),EvEv(kmv)k=(0,0,0)kmv=2Pa0(0.6223,0.2953,0),EbpTersoffEB,Wdg[1],En(k),4(Mc)()Emk[7],Em[1]:Em=12{kBZA(k)[144n=1En(k)+1Mc4+Mcn=5En(k)]}(5),kBZk,A(k)k,En(k)kEn(k),,(5)k4,Mc[2],(5)Mc=5,EmEF,EmEFTer2soff[5],2EsF=Em,2:Bp=Em-Ev(6)(3)(4)(6)1(b),TersoffMonchEBEbpEm2EsF,42SiGeGaPInPAlAsGaAsInAsAlSbGaSbInSb,[8],En(k),1,Ceperley2Alder2,BacheletBHSEcat,AlSbGaSbInSb2015Rdy,22.5Rdy,2(SO)($0),SOEv$0ö31,En(k),1SO$0,Eg,dirEg,ind1(LDA)1Expt.Eg,indEg,ind1,Eg,dirEg,ind(LDA)(Expt)2(LDA)Tersoff[5]EB,2(LDA)Eg,dirEg,ind,En(k),[11],Eg,indEB41423Tersoff,,1Eg,ind(LDA)(Expt.),En(k)5,,(5)Em60k2Em-Ev,Tersoff[5,11]Monch[6]EB-EvEbp-Ev,exptBp1a0S0$0(eV);Eg,dirEg,ind(Expt.)(LDA)Tab.1Latticeconstantsa0,experimentalvaluesofS0split$0;theexperimentalandthecalculatedval-uesofdirectbandgapEg,dir,indirectbandgapEg,indSemiconductorLatticecons2tantsS0splitDirectbandgapEg,diröeVIndirectbandgapEg,indöeVa0önm$0öeV(LDA)Expt.(LDA)Expt.Si0.5430.042.510.631.12aGe0.5650.29-0.020.090.66aGaP0.5450.081.951.632.27aInP0.5870.110.801.34b1.542.03aAlAs0.5650.281.941.292.15aGaAs0.5650.340.501.43b0.941.71aInAs0.6060.39-0.170.36b0.931.52aAlSb0.6140.701.360.961.63bGaSb0.6080.750.030.70b0.260.80bInSb0.6480.98-0.330.18b0.340.62ba[9];b[10]52Bp=(Em-Ev)(exptBp),GeAlSb011eV,,;,2Em-EvTersoffMonchEB-EvEBp-Ev,Tersoff,22Em-EvEB-Ev[5,11]Ebp-Ev[6][10]Au-PexptBpTab.2ThecalculatedvaluesofEm-EvonthispaperandthecorrespondingvaluesofEB-Ev[5,11],Ebp-Ev[6],andtheexperimentalvaluesofAu-PtypebarrierheightexptBpinreference[10]SemiconductorThispaperEm2EvöeVCNLEB2EvöeVETBEbp2EvöeVp2typebarrierheightexptBp(Au)öeVSi0.300.360.030.32Ge-0.050.18-0.280.07GaP0.860.810.830.94InP0.830.860.860.77AlAs1.001.050.920.96GaAs0.570.500.520.52InAs0.560.500.500.47AlSb0.420.450.530.55GaSb0.030.070.160.07InSb-0.010.010.220.00Schottky,TersoffEB,()En(k),(),,,2(2)22,EsF(n=p)Ei1(b)EsFEi,1(a)(b)BpBn,,2BpBn2EsF(,n=0p=0),,EsFEB,EBEsF,EBEm,EBEmEsF(453)5144:21,.[M],:,2000:541722LeeYeh.MLSDriving,w3.Epson.com.twöelectronicsöeventö22LeeYeh-1.pdf[N],2001:2113.MLSDriver,w3.Epson.com.twöelectronicsöevent[N],2000:4124.CMOS[M],:,2000:206209(ZHONGRui),197510,,,(WEITongli),19344,,,,ULSIULSI(415)2,2nBnBp=Eg-Bn[1(c)]Bp,2pBp,p,Bp(Bn)(),np,Bp(Bn=Eg-Bp)2,2Em-EvEB-EvexptBp(Au)1,.$Ev.,1991;40(10):168316882,,.Em.,2001;50(2):2732773SchottkyW.Zurhalbleitertheoriedersperrschict2undspitzengleichrichter.ZPhys,1939;113:3674144CowleyAM,SzeSM.Surfacestatesandbarrierheightofmetal2semiconductorsystems.JApplPhys,1965;36:321232205TersoffJ.Schottkybarrierheightsandthecontinuumofgapstates.PhysRevLett,1984;52:4654686MonchW.Empiricaltight2bindingcalculationofthebranch2pointenergyofthecontinuumofinterface2in2ducedgapstates.JApplPhys,1996;80:507650827ChadiDJ,CohenML.Specialpointsinthebrillouinzone.PhysRev,1973;B8:574757538BacheletGB,HamannDR,SchlterM.Pseudopoten2tialsthatwork:fromHtoPu.PhysRev.,1982;B26:419942289Landolt2Bornstein,NewSeries,GroupË,Vol,22,pt.a,editedbyO.Madelung,Springer,NewYork(1982)10TersoffJ.Schottkybarrierandsemiconductorbandstructures.PhysRev,1985;B32:6968697111TersoffJ.Calculatitonofschottkybarrierheightsfromsemiconductorbandstructures.SurfaceScience,1986;168:275284(LIShuping)197311,,,1996,,3544: