Study of point defect clusters in high purity single crystals of silicon grown by Czochralski and float-zone methods by diffuse X-ray scattering technique

1995 ◽  
Vol 156 (4) ◽  
pp. 377-382 ◽  
Author(s):  
R.R Ramanan ◽  
G Bhagavannarayana ◽  
Krishan Lal
Keyword(s):  
Point Defect ◽  
Single Crystals ◽  
High Purity ◽  
X Ray ◽  
Defect Clusters ◽  
Float Zone ◽  
X Ray Scattering ◽  
Scattering Technique ◽  
Point Defect Clusters ◽  
Ray Scattering

Study of point defects in as-grown and annealed bismuth germanate single crystals

2005 ◽  
Vol 38 (3) ◽  
pp. 448-454 ◽  
Author(s):  
G. Bhagavannarayana ◽  
A. Choubey ◽  
Yu. V. Shubin ◽  
Krishan Lal
Keyword(s):  
Point Defect ◽  
Single Crystals ◽  
Point Defects ◽  
Bismuth Germanate ◽  
Cluster Radius ◽  
X Ray ◽  
Defect Clusters ◽  
X Ray Scattering ◽  
Point Defect Clusters ◽  
Ray Scattering

Point defects and their clusters in bismuth germanate single crystals free from grain boundaries and having low density of dislocations were studied by high-resolution diffuse X-ray scattering measurements. Differences in defects in the colourless crystals (type A) and the crystals having yellow tinge (type B), which were grown with different raw materials, were investigated. In addition, interesting differences in defect structures in specimens from different regions of the same boule were investigated. Specimens with diffracting surfaces along (111), (112) and (100) planes were studied. A multicrystal X-ray diffractometer employing a well collimated and highly monochromated Mo Kα1 beam and set in (+,−,−,+) configuration was employed. The diffraction curves of all the samples were quite narrow with half-widths in the range 7–11 arcsec, which are close to the theoretically expected values, if instrumental broadenings are taken into account. The observed distribution of diffuse X-ray scattering (DXS) intensity showed that not all the point defects are isolated but a significant fraction are agglomerated into clusters. Experimental data of DXS intensity were analysed by using a phenomenological model for a small concentration of dislocation loops wherein the point defects are loosely clustered with weak interactions among them. From this analysis, the cluster radius R cl, cluster volume A cl, the number of point defects within a cluster N cl and the relative concentration of the point-defect clusters among the samples were estimated. It was observed that cluster sizes do not vary from sample to sample. However, it was found that the concentration of clusters is approximately twice in the coloured sample compared with that of the colourless sample from the same boule. Annealing of the crystals at 1273 K produced an increase in point-defect clusters by a factor of ∼200. It was accompanied by a reduction in volume of clusters by a factor of ∼0.14.

Evolution of Pore Ordering during Anodizing of Aluminum Single Crystals: In Situ Small-Angle X-ray Scattering Study

2021 ◽  
Author(s):  
Ilya V. Roslyakov ◽  
Andrei P. Chumakov ◽  
Andrei A. Eliseev ◽  
Alexey P. Leontiev ◽  
Oleg V. Konovalov ◽  
...  
Keyword(s):  
Single Crystals ◽  
Small Angle ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Study ◽  
Ray Scattering

A New X-Ray Scattering Method for Determining Pore-Size Distribution in Low-k Thin Films

2001 ◽  
Vol 714 ◽  
Author(s):  
Kazuhiko Omote ◽  
Shigeru Kawamura
Keyword(s):  
Thin Films ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Gas Adsorption ◽  
Size Distributions ◽  
X Ray ◽  
X Ray Scattering ◽  
Pore Size Distributions ◽  
Scattering Technique ◽  
Ray Scattering

ABSTRACTWe have successively developed a new x-ray scattering technique for a non-destructive determination of pore-size distributions in porous low-κ thin films formed on thick substrates. The pore size distribution in a film is derived from x-ray diffuse scattering data, which are measured using offset θ/2θ scans to avoid strong specular reflections from the film surface and its substrate. Γ-distribution mode for the pores in the film is used in the calculation. The average diameter and the dispersion parameter of the Γ-distribution function are varied and refined by computer so that the calculated scattering pattern best matches to the experimental pattern. The technique has been used to analyze porous methyl silsesquioxane (MSQ) films. The pore size distributions determined by the x-ray scattering technique agree with that of the commonly used gas adsorption technique. The x-ray technique has been also used successfully determine small pores less than one nanometer in diameter, which is well below the lowest limit of the gas adsorption technique.

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