Selection of CVD Diamond Crystals for X-ray Monochromator Applications Using X-ray Diffraction Imaging

Abstract

A set of 20 single crystal diamond plates synthesized using chemical vapor deposition (CVD) was studied using X-ray diffraction imaging to determine their applicability as side-bounce (single-reflection) Laue monochromators for synchrotron radiation. The crystal plates were of optical grade (as provided by the supplier) with (001) nominal surface orientation. High dislocation density was found for all samples. Distortions in the crystal lattice were quantified for low-index Laue reflections of interests using rocking curve topography. Maps of effective radius of curvature in the scattering plane were calculated using spline interpolation of the rocking curve peak position across the studied plates. For several selected plates, nearly flat regions with large effective radius of curvature were found ( R 0 ≳ 30 - 70 m, some regions as large as 1 × 4 mm 2 ). The average width of the rocking curve for these regions was found to be about 150 μ rad (r.m.s.). These observations suggest that the selected CVD diamond plates could be used as intermediate-bandwidth monochromators refocusing the radiation source to a specific location downstream with close to 1:1 distance ratio.

Chemical Vapor Deposition Single‐Crystal Diamond: A Review

“…[72] The further growth on the side plane confirmed a strong decrease by an order of magnitude in dislocation density. [26,72] The SC CVD diamond is used in X-ray beam position monitors, [73] X-ray monochromators, [74] and splitters, [75] detectors of charged high energy particles, [76,77] neutrons, [78][79][80] UV light, [81] and in dosimeters in radiotherapy, particularly for proton therapy [82] to combine good electronic properties and radiation [50] Copyright 2019, Wiley-VCH.…”

“…The SC CVD diamond is used in X‐ray beam position monitors, [ 73 ] X‐ray monochromators, [ 74 ] and splitters, [ 75 ] detectors of charged high energy particles, [ 76,77 ] neutrons, [ 78–80 ] UV light, [ 81 ] and in dosimeters in radiotherapy, particularly for proton therapy [ 82 ] to combine good electronic properties and radiation hardness. Diamond detector structure with pair of planar metal electrodes on two sides of the diamond plate is a common feature of such devices (UV sensors may have electrodes on one plane only).…”