ocivm.com > LEED / AES Spectrometers > mini-LEED with Integral Retraction & Shutter: LEED 450-MAX (Model BDL450-MAX)
Based on Low Energy Electron Diffraction (LEED) and Auger Electron Spectroscopy (AES)
The LEED450-MAX combines cutting-edge Low-Energy Electron Diffraction (LEED) and Auger Electron Spectroscopy (AES) capabilities in a compact, reliable package. Featuring a miniature electron gun, a set of concentric grids, and a conductive, phosphor-coated screen, this high-performance instrument delivers exceptionally sharp and bright LEED patterns.
Designed for ease of use, the LEED450-MAX operates with a modern digital power supply and a robust retraction mechanism, ensuring smooth, dependable day-to-day operation, as trusted by our extensive user base for decades. The wide viewing angle (92° at 38 mm sample distance) and minimal screen shadowing by the electron gun maximize the visible LEED pattern, providing unparalleled clarity and precision for surface science research.
Mini model with maximized display for basic surface crystallography of single crystals and "in-situ" epitaxy. The LEED 450-MAX is capable of providing LEED and AES data for a wide range of samples. The miniature instrument size allows for easy installation to smaller UHV systems. Materials suitable for charaterization should be single crystals and epitaxial films in categories such as: 2D materials, semiconductors, metals, oxides and magnetic films.
For seamless integration, 3D step files are available for most models on the PDF Downloads page.
Calculation formula for flange sample distance & retraction length for LEED 450-MAX (BDL450-MAX):
FS = 159mm + 2LMX - OV; where FS is the flange to sample distance, LMX is the retraction length, OV is the overlapping length, PL is the port length and NL is the nipple length.
For detailed specifications, download the LEED 450 MAX Specifications (.pdf). For more information, see the configuration guide or the brochure below.
| Optics | |
|---|---|
| Glass-display | Fused silica coated with indium-tin oxide conductive layer and P31 phosphor (ZnS:Ag:Cu-green, 525 nm wavelength) |
| Acceptance angle | 92° angle of acceptance from sample at a distance of 38 mm |
| Retarding Field Analyser | Concentric assembly of hemispherical grids |
| Working distance | 10 mm from sample |
| Grid material | Gold coated St-Steel wire mesh (100 mesh, 81% transparency) |
| Energy Resolution | 0.2% - 0.5% at low modulation voltages |
| Monitoring | 4.5" standard viewport |
| Linear motion | up to 100 mm 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 | CF4.5" (DN63CF) With Oversized tubing 76 mm (3”) O.D |
| Bakeability | Under vacuum, 250 °C maximum |
| Integral Miniature Electron Gun | |
| Beam energy system | LEED – 5 eV to 750 eV, AES – 5 eV to 3000 eV |
| Beam current | LEED – 2 μA at 100 eV and 0.5 mm beam size, AES - up to 100 μA at 3 keV |
| Beam size | from 1 mm 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 | 10 mm lens diameter and 80 mm length |
Download LEED 450-MAX Configuration Guide (.pdf).
