Reciprocal space maps
Six-axis sample stage on high resolution goniometer.
Absolute angular resolution = 0.0001 degrees.
High Resolution setup for epitaxial layers
Incident beam optics
Hybrid monochromater consisting of closely coupled x-ray mirror and 4 bounce Ge 220 monochromator.
Resolution = 18 arc-seconds.
Diffracted beam optics
1. Fixed slit
2. Three bounce Ge 220 analyzer. Resolution = 12 arc-seconds
High-resolution diffraction is a collection of application techniques that is applied for the measurements of nearly-perfect materials. Most semiconductor device structures, based on silicon, silicon-germanium, III-V and II-VI compounds, are epitaxially grown from the gas phase onto a substrate. These films are nearly-perfect crystalline films and contain a low dislocation density. Properties of these films are largely determined by their composition and structure. Information from these layers, such as layer thickness, composition, strain and relaxation, can be obtained by measuring rocking curves and reciprocal space maps using high-resolution optics. Defect structures inside the layers can be revealed by X-ray topography.
Solutions for high-resolution diffraction
High-resolution diffraction experiments require a highly monochromatic beam with a well defined wavelength and equatorial divergence. PANalytical X’Pert PRO MRD systems can be configured with a hybrid monochromator or a high-resolution monochromator to fulfil these requirements. With PANalytical’s X’Pert PRO Extended MRD system, an X-ray mirror and a high-resolution monochromator can be placed in line to deliver an incident X-ray beam that is not only highly monochromatic with a low divergence, but also has a high intensity. This high intensity is used to uncover the weakest details in a diffraction experiment.X’Pert Epitaxy and Smoothfit provides functionality to analyze rocking curves, reciprocal space maps and wafer maps. Rocking curves can be simulated and fitted using patented algorithms.