The LEED 800 MCP with integral shutter has LEED and AES capabilities using a miniature electron gun, set of concentric grids and a conductive, phosphor coated screen. In addition, this optic model incorporates the high gain of microchannel plates. It is an extremely reliable high-performance LEED instrument which operates with up to date digital power supply. The retraction mechanism has outstanding mechanical properties ensuring smooth day-to-day operation as experienced by our large user base over decades. The wide viewing angle (101° at 75mm sample distance) and minimal shadowing of the screen by the miniature electron gun give a maximum visible LEED pattern.
The LEED 800 MCP is especially good at providing LEED and AES data of organic samples. The larger size allows for higher angular and energy resolution and the gain from the MCPs allows better focusing of LEED imaging.
For seamless integration, 3D step files are available for all models.
LEED 800 MCP (Model BDL800IR-MCP) calculation formula for Flange-Sample distance
& Retraction length:
FS = 165.5mm + 2 LMX – OV; where FS is the flange to sample distance, LMX is the retraction length and OV is the overlapping length.
For detailed specifications, download LEED 800 MCP Configuration and Specifications (PDF).
|Glass-display||Fused silica coated with indium-tin oxide conductive layer and P31 phosphor (ZnS:Ag:Cu-green, 525 nm wavelength)|
|Acceptance angle||101 °C angle of acceptance from sample at a distance of 75mm|
|Retarding Field Analyser||Concentric assembly of hemispherical grids|
|Working distance||20mm from sample|
|Grid material||Gold coated tungsten wire mesh (100 mesh, 81% transparency)|
|Energy Resolution||0.2% - 0.5% at low modulation voltages|
|Monitoring||8" standard viewport|
|Linear motion||up to 100mm retraction from sample; linear ball bearing and acme thread with all spring electr. connections|
|Integral Shutter||Manual shutter driven by rotary feedthrough|
|Magnetic shielding||Mu-metal cylinder with front cover for maximum attenuation|
|Assembly||Extreme-high-vacuum compatibility with stainless steel, high alumina and Au-plated copper alloy materials|
|Mounting||8"(CF150) double sided conflat flange with sample distance 145mm – 400mm|
|Bakeability||Under vacuum, 250 °C maximum|
|Integral Miniature Electron Gun|
|Beam energy system||LEED – 5 eV to 750 eV, AES – 5 eV to 3000eV|
|Beam current||LEED – 2 µA at 100 eV and 0.5mm beam size, AES - up to 100 µA at 3 keV|
|Beam size||from 1mm to 250 µm - adjusted by Wehnelt potential, limited by exchangeable aperture down to 50 µm|
|Electron source||Tungsten-2% thoriated filament standard,
single crystal LaB6 filament optional
|Energy spread||0.45 eV (thoriated - tungsten filament)|
|Overall size||10mm lens diameter and 80mm length|
|Channel diameter||25 microns|
|Center to center spacing||32 microns|
|Bias angle||8 °|
|Electron gain||104 to 105 per plate|
The LEED 800 MCP optics is controlled using either a LPS075-D or LPS300-D power supply. The LPS075-D is used to operate the optic in LEED mode only whereas the LPS300-D in conjunction with the LOA10-AES lock-in controller and AUS30 input coupler is used to operate the optics in LEED and AES modes. Integral shutter (Model ISH-8) and LaB6 filament (Model LaB6) are further options. The MCPS01/02 controllers are used for operation of the microchannel plates.
For more information, download LEED 800 MCP Configuration and Specifications (PDF).