RHEED

RHEED stands for Reflection High Energy Electron diffraction. RHEED is quite similar to LEED.

Related Topics:
Electron diffraction - LEED

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RHEED uses an electron gun and a fluorescent screen for creating pictures showing the structure and/or morphology of a crystal surface.

Related Topics:
Electron gun - Fluorescent - Morphology - Crystal

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RHEED uses much higher electron energy (5-100keV) and lower impact angles (

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In RHEED, the reciprocal lattice is 2-dimensional if the crystal is single crystalline and the surface is flat in nanometer scale. This characteristic makes the reciprocal lattice appear as lines instead of dots in 3-dimensional case. This way the reciprocal lattice lines touch the Ewald-sphere more often than normal and the Laue diffraction condition is fulfilled quite often in the forward direction of the electron beam, where the fluorescent screen is mounted. The diffraction image changes in other cases, depending on the crystallinity and the morphology of the crystal.

Related Topics:
Reciprocal lattice - Single crystalline - Nanometer - Laue diffraction - Crystallinity

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Pros of RHEED:

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Real-Time Analysis: RHEED is often used for monitoring crystal growth, as it doesn't block the direction vertical to the surface of the crystal, which is observed. It's also very sensitive to surface roughness.

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Especially for the crystals that can be easily damaged, MCP-RHEED is used.

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