JSM 840

SM-840 examines structure by bombarding the specimen with a scanning beam of electrons and then collecting slow moving secondary electrons that the specimen generates. These are collected, amplified, and displayed on a cathode ray tube (CRT, typically a slower version of the picture tube of a television set) although now, most are driven by PCs and these computer-generated images are displayed on LCDs. The electron beam is scanned using a raster pattern so that an image of the surface of the specimen is formed. Specimen preparation typically includes drying the sample and making it conductive to electricity, if it is not already. Photographs are taken at a very slow rate of scan in order to boost the signal and capture greater resolution. All our SEMs use digital imaging. SEM is typically used to examine the external structure of objects that are as varied as biological specimens, rocks, metals, ceramics and almost anything that can be observed in a dissecting light microscope. The JEOL JSM-840 is used for conventional samples of normal sizes using the airlock. These specimens are usually mounted on multiple "stubs" (up to 4 specimen stubs fit) and each are observed individually. An alternative for large specimens is to vent the column an use the specimen drawer, which allows silicon disks and other objects to be viewed, but takes longer to pump as the whole specimen viewing area is brought to room pressure.
JSM 840
Magnification 10 to 300000 x
Accelerating voltage 1000 to 40000 VA
Electron Microscope Type SEM
Microscope Type Electron
Additional Specifications accelerating voltages:      
1,000 volts to 40,000 volts (1,000 volt increments)     
useful magnification:      
X 10 to X 300,000     
30 Ångstrom resolution (LaB6 source at 40KV)     
solid state backscattered electron detector     
Kevex X-ray analyzer with light element capabilities and IXRF software and digital imaging capability


Equipped for x-ray feature analysis, mapping and quantitative analysis     
Nabity e-beam lithography package




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