Optical properties of thin nanosilicon films

The present study is objected to develop an analytical remote optical diagnostics of the functionalized carbons surface. Carbon composites with up to 1 mmol g−1 of irreversibly adsorbed bromine were produced by the room temperature plasma treatment of an activated carbon fabric (ACF) derived from polyacrylonitrile textile. The brominated ACF (BrACF) was studied by elastic optical scattering indicatrix analysis at wavelength 532 nm. The obtained data were interpreted within results of the thermogravimetric analysis, X-ray photoelectron spectroscopy and temperature programmed desorption mass spectrometry. The bromination dramatically reduces the microporosity producing practically non-porous material, while the incorporated into the micropores bromine induces the dielectric and structural impact on surface polarizability and conductivity due to the charging effect. We have found that the elastic optical scattering in proper solid angles in the forward and the backward hemispheres is sensitive to the kind of the bromine bonding, e.g., physical adsorption or chemisorption, and the bromination level, respectively, that can be utilized for the express remote fabrication control of the nanoscale carbons with given interfaces.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-017-1873-7) contains supplementary material, which is available to authorized users.

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“…The scattering signal integrated into spherical coordinates [ 37 , 38 ] for the sectors A , B , C , and D are presented in Fig. 5 .…”

Section: Resultsmentioning

confidence: 99%

Surface Response of Brominated Carbon Media on Laser and Thermal Excitation: Optical and Thermal Analysis Study

et al. 2017

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“…One of the main elements of polycrystalline materials is grain boundaries. Grain boundaries are of great importance for controlling the properties of materials that is due to their significant impact on electrophysical, optical, mechanical and other properties, which are important from the point of view of practical applications [1][2][3][4][5][6]. Grain boundaries in polycrystals form a system of internal surfaces connected by means of a triple or multiple joints.…”

Section: Introductionmentioning

confidence: 99%

Topological Analysis of the Effect of Annealing on the Grain-Boundary Structure of Polysilicon Films

Rodionova¹,

Lytvyn²,

Len³

et al. 2021

J. Nano- Electron. Phys.

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The effect of annealing on the grain-boundary structure of phosphorus-doped silicon films obtained by chemical vapor deposition was investigated by comparative analysis of atomic force microscopy data and existing model concepts. It is shown that the decisive factor for the applicability of the topographic model is the character of grain growth in the films. The model is applicable for annealing temperatures  1000 C, at which normal grain growth is observed. In this temperature range, the distributions of different types of grain boundaries in polysilicon films are symmetric with respect to growing and disappearing boundaries. The structure of polysilicon films is equiaxed, there is no preferred orientation. At annealing temperatures  1000 C, anomalous grain growth takes place in the films, and the distribution of the types of grain boundaries indicates that the topological model is inapplicable in this temperature range. It can be assumed that the differences in the ratios of growing and disappearing grain boundaries in polysilicon films at different annealing temperatures are due to different mechanisms and driving forces of grain growth during normal and abnormal growth. With normal grain growth, the driving force prevails, that is caused by the difference in the density of dislocations in the adjacent grains. With abnormal grain growth, the driving force prevails, that is due to the difference in the average surface energy of the grains, which causes a sharp increase in the rate of grain growth.

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