電子顯微術(shù)ppt課件-在線瀏覽
2025-06-29 03:17本頁面
【正文】 p e c i m e nP r e pa r a t i o nE a sy C o m pl i c a t e d E a sySp e c i m e n Si z e L a r g e Sm a l l L a r g eMe t a l c o a t i ng N o t ne c e ssa r y N o t ne c e ssa r y N e c e ssa r yIm a g eT r a nsm i t t e d Im a g eo r Su r f a c e Im a g eT r a nsm i t t e d Im a g e Su r f a c e Im a g e H a r d w a r eS o f t w a r e ? P e r f o r m a n c eT y peCh a ra ct eris t ic第一節(jié)結(jié)構(gòu)原理 掃描電鏡基本上是由電子光學(xué)系統(tǒng)、信號接收系統(tǒng)、供電系統(tǒng)、真空系統(tǒng)等四部分組成。 在掃描電鏡中，電子槍發(fā)射出來的電子束，經(jīng)三個電磁透鏡聚焦后，成直徑 20微米 ~25197。置于末級透鏡上部的掃描線圈能使電子束在試樣表面上做光柵狀掃描。 值得強調(diào)的是，入射電子束在試樣表面上是逐點掃描的，像是逐點記錄的，因此試樣各點所激發(fā)出來的各種信號都可記錄下來。 SE Detector Specimen CRT Camera Amplifier Image Signal High Voltage Deflection Coils Deflection Amplifier Vacuum Pump Filament Wehnelt Electron Gun Anode Condenser Lens Deflection Coils Objective Lens Specimen Chamber Scanning Electron Beam Mag. Control Configuration of a scanning electron microscope PG1 PG2 Filament Condenser Lens aperture Orifice NV Vacuum Gauge Vacuum controller (Realtime) Vacuum condition preset RP1 RP2 DP Low Vacuum Condition BSE detector V8 V6 V9 V3 V4 V1 Specimen V5 V7 High Vacuum Condition V2 Block diagram of evacuating system Image Sample Objective Lens (Illumination Source) Lump O M Condenser Lens Projection Lens Screen Image Image Sample Sample Objective Lens Electron Source Condenser Lens Deflection Coils SE Detector C R T T E M S E M Fluorescent screen Scanning Difference among OM, TEM and SEM FE Tip Tungsten Filament 750μ m Electron Source Type of Emission Operating Vacum (Pa) Brightness (A/cm2?str) Source Size (μ m) Energy Spred (eV) Life Time (h) Tungsten Filament Thermonic Field Emission Cold FE 105 ～ 108 5x105 108 30 50 2022 Energy Spread Effect of chro
教學(xué)課件相關(guān)推薦
鄂ICP備17016276號-1