第3-1章 透射电子显微镜--原理

ZhengminLi1TransmissionElectronMicroscope(TEM)ZhengminLi2z1932-1933,(Ruska)z1940,ZhengminLi3z100~200nmZhengminLi4zEM-902ZhengminLi5z(JEOL)JEM-1230ZhengminLi6zPhilipsEM400TZhengminLi7PhilipsTECNAI-20ZhengminLi8TEMTEMzzZhengminLi9TEMTEMz:z:z:ZhengminLi10ZhengminLi11zZhengminLi12————50ZhengminLi13ZhengminLi14ZhengminLi15ZhengminLi16WhyaWhyaFieldemissionFieldemissiongun(gun(FEG)?FEG)?z4itemsforconsideration:••BrightnessBrightness••LifetimeLifetime••Pressure(vacuum)=relatedtothepricePressure(vacuum)=relatedtotheprice••MaintenanceMaintenanceZhengminLi17Brightness(Candela)LifetimePressureMaintenanceTungsten840hr1.3E-4mBarCleaningofWehneltLaB6402000Hr2E-7mBar(-1IGP)DriftSchottkyZrOonW30007000Hr5E–9mBar(-2IGP’s)ColdFEG3000?5E-11mBarFlashonceadayZhengminLi18ZhengminLi19z3-5ZhengminLi20z0-20ZhengminLi21zzM=M0.Mi.MpzM0---50-100Mi----0-20Mp---100-150M1000-200,000ZhengminLi22ZhengminLi23TTEEMMZhengminLi24zZhengminLi25ZhengminLi26zZhengminLi27ZhengminLi28SpecimenHoldersZhengminLi29HeatingHighTiltCoolingStrainingAnalyticalSpecimenHoldersZhengminLi30Hexring?ToolHexringAnti-twistwasherSpecimengridTheanti-twistwasherisusedtomaintainalignmentofgridswhenspecimensareclampedbetweentwogrids.Normally,theanti-twistwasherisnotusedwhenclampingsinglegrids,foldinggridsanddiscspecimens.MakesurethespecimenissecurelyclampedbytheHexring?(loosespecimenswillpreventthefullmicroscoperesolutionfrombeingobtained.)TipdetailforspecimenloadingTipdetailforspecimenloadingZhengminLi31OLPolepieceZhengminLi32,:,,;10-4~10-6Torr,,,10-3Torr,,10-4~10-6Torr,ZhengminLi33:z,z,zZhengminLi34(1),z,;z,ZhengminLi35Au0.204nmAu0.204nmZhengminLi36z2‰‰,‰10080,0.2mm,0.1nm0.2mm,200,,ZhengminLi37z3z,zZhengminLi38TEM™™™ZhengminLi39ZhengminLi40ZhengminLi411“”ZhengminLi42ZhengminLi43ZhengminLi441nm.1nm10nmZhengminLi45TEMABHREM(HREM)ZhengminLi46