Full Flange Size LEED for Higher Angular and Energy Resolution
- High energy and image resolution for LEED and AES with no Moire pattern interference
- Large Angle (100°) Fluorescent LEED Display and superior magnetic shielding
- Miniature electron gun with large coherence width double focusing
- Suitable for In Situ Film Growth Monitoring
- Low outgassing rate
- Convenient LEED Image Capture with External CCD Camera
- Simple and Powerful Operation with Digital Controller
The LEED 800 with integral shutter has LEED and AES capabilities using a miniature electron gun, set of concentric grids and a conductive, phosphor coated screen. 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 LEED 800 delivers exceptionally sharp and bright LEED patterns with high resolution in k-space (typical transfer width of 300 Å at 100 eV). The wide viewing angle (100° at 75 mm sample distance) and minimal shadowing of the screen by the miniature electron gun give a maximum visible LEED pattern.
The LEED 800 is capable of providing LEED and AES data for a wide range of samples. The larger size allows for higher angular and energy resolution.
For seamless integration, 3D step files are available for all models.
LMX length calculation for LEED 800 (model BDL800IR):
FS = 155 mm + 2LMX – OV + WD; where FS is the flange to sample distance, LMX is the retraction distance, OV is the overlapping distance, WD is the working distance and the 155 mm value is a constant related to this optic model.
If the calculated FS value is longer than the actual port length a nipple adapter can be added as a spacer between the LEED optics and the UHV chamber. The nipple length can be calculated as follows:
NL = FS – PL; where NL is nipple length and PL is port length.
Configuration Guide and Specifications
The LEED 800 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.
Fused silica coated with indium-tin oxide conductive layer and P31 phosphor (ZnS:Ag:Cu-green, 525 nm wavelength)
100° angle of acceptance from sample at a distance of 75 mm
Concentric assembly of hemispherical grids
18 mm from sample
Gold coated tungsten wire mesh (100 mesh, 81 % transparency)
0.2 % - 0.5 % at low modulation voltages
8" standard viewport
Up to 150 mm retraction from sample (100 mm standard); linear ball bearing and acme thread with all spring electr. connections
Manual shutter driven by a rotary feedthrough
Mu-metal cylinder with front cover for maximum attenuation
Extreme-high-vacuum compatibility with stainless steel, high alumina and Au-plated copper alloy materials
8"(CF150) double sided conflat flange with sample distance 145 mm – 500 mm
Under vacuum, 250 °C maximum
LEED – 2 µA at 100 eV and 0.5 mm beam size, AES - up to 100 µA at 3 keV
From 1 mm to 250 µm - adjusted by Wehnelt potential, limited by exchangeable aperture down to 50 µm
Tungsten-2 % thoriated filament standard,
single crystal LaB6 filament optional
0.45 eV (thoriated - tungsten filament)
10 mm lens diameter and 80 mm length
For full specifications and more information about product options, please do not hesitate to contact your local sales representative.