简介:TheexitwavefunctionincludingzeroandhighorderLauezoneshasbeensimulatedbybothmulti-slicemethodandelectrondynamicdiffractionanalyticalexpression.Coincidenceofthesimulationsbythesetwomethodswasachieved.ThecalculatedresultsshowedthattheexitwavefunctionhighlydominatedbyzeroorderLauezone,whilehighorderonesmodifytheexitwavefunctiontosomeextentdependingonthesituation.HighorderLauezoneeffectsbecomeimportantforthefollowingcases:sampleconsistsoflightelements,thethicknessisverythin,latticeplanarspacingperpendiculartothedirectionoftheincidentbeamislarge,andtheelectronbeamhaslongwavelength.InthesecasestheexitwavefunctionshouldbecorrectedbyaddinghighorderLauezoneeffects.TheanalyticalexpressioniseffectiveandconvenientfordealingwithhighorderLauezoneeffects.
简介:Intrinsiccarrierconcentration(ni)isoneofthemostimportantphysicalparametersforunderstandingthephysicsofstrainedSiandSi1-xGexmaterialsaswellasforevaluatingtheelectricalpropertiesofSi-basedstraineddevices.Uptonow,thereportonquantitativeresultsofintrinsiccarrierconcentrationinstrainedSiandSi1-xGexmaterialshasbeenstilllacking.Inthispaper,byanalyzingthebandstructureofstrainedSiandSi1-xGexmaterials,boththeeffectivedensitiesofthestatenearthetopofvalencebandandthebottomofconductionband(NcandNv)at218,330and393KandtheintrinsiccarrierconcentrationrelatedtoGefraction(x)at300KweresystematicallystudiedwithintheframeworkofKPtheoryandsemiconductorphysics.ItisfoundthattheintrinsiccarrierconcentrationinstrainedSi(001)andSi1-xGex(001)and(101)materialsat300KincreasessignificantlywithincreasingGefraction(x),whichprovidesvaluablereferencestounderstandtheSibasedstraineddevicephysicsanddesign.