Mechanism of ultra-low reflectance for nanocrystalline Si/crystalline Si structure formed by surface structure chemical transfer method

Abstract Black silicon layers were formed on silicon substrate by the surface structure chemical transfer method and by anodic etching method. Properties of microstructure of formed layers were experimentally studied by the electron microscopy methods (TEM) and characterized by statistical, Fourier and multifractal methods. Theoretical structures with defined fractal properties and surface roughness were generated and their microstructure properties were evaluated. Obtained results were used for the explanation of the real structure development during the forming procedure. By using of this approach, we study the correlation of roughness and fractality with optical properties. Black silicon layers were also investigated by using of Raman scattering method. Optimized theoretical model describing the 1st order of black Si Raman scattering profile was constructed and used for evaluation of the biaxial tensile stress introduced during etching procedure.

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High conversion efficiency of crystalline Si solar cells using black − Si fabricated by SSCT method

Journal of Electrical Engineering ◽

10.1515/jee-2017-0053 ◽

2017 ◽

Vol 68 (7) ◽

pp. 37-42 ◽

Cited By ~ 2

Author(s):

Kentaro Imamura ◽

Yuya Onitsuka ◽

Yuya Sakae ◽

Hikaru Kobayashi

Keyword(s):

Conversion Efficiency ◽

Internal Quantum Efficiency ◽

Wavelength Region ◽

Minority Carrier Lifetime ◽

High Conversion ◽

Short Wavelength Region ◽

High Conversion Efficiency ◽

Chemical Transfer ◽

Phosphosilicate Glass ◽

Nanocrystalline Si

Abstract We have developed a technology for fabrication of black − Si by use of the surface structure chemical transfer (SSCT) method. The ultralow reflectance below 3% results from formation of a graded porosity structure of a nanocrystalline Si layer formed by the SSCT method. The nanocrystalline Si layer with an extremely large surface area is effectively passivated by deposition of phosphosilicate glass (PSG) followed by heat treatment at 925 ◦C. After PSG passivation, the minority carrier lifetime greatly increases, and the internal quantum efficiency in the short wavelength region is also greatly increased. Using the SSCT method and the PSG passivation method, the high conversion efficiency of 19.7% is achieved.

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About complex refractive index of black Si

Journal of Electrical Engineering ◽

10.1515/jee-2017-0063 ◽

2017 ◽

Vol 68 (7) ◽

pp. 81-83

Author(s):

Emil Pinčík ◽

Robert Brunner ◽

Hikaru Kobayashi ◽

Milan Mikula

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Complex Refractive Index ◽

Black Silicon ◽

Nano Crystalline ◽

Light Region ◽

Chemical Transfer ◽

Transfer Method ◽

Different Thickness ◽

Ir Light

Abstract The paper deals with the complex refractive index in the IR light region of two types of samples (i) as prepared black silicon, and (ii) thermally oxidized black silicon (BSi) nano-crystalline specimens produced both by the surface structure chemical transfer method using catalytic Ag evaporated spots (as prepared sample) and by the catalytic Pt catalytic mesh (thermally oxidized sample). We present, compare, and discuss the values of the IR complex refractive index obtained by calculation using the Kramers-Krönig transformation. Results indicate that small differences between optical properties of as prepared black Si and thermally oxidized BSi are given by: (i) – oxidation procedure, (ii) – thickness of the formed black Si layer, mainly, not by utilization of different catalytic metals, and by iii) the different thickness. Contamination of the surface by different catalytic metals contributes almost equally to the calculated values of the corresponding complex refractive index.

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Surface Structure of the Spores of Glugea Weissenbergi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006310x ◽

1969 ◽

Vol 27 ◽

pp. 238-239

Author(s):

Sanford H. Vernick ◽

Anastasios Tousimis ◽

Victor Sprague

Keyword(s):

Electron Microscope ◽

Surface Structure ◽

Transmission Electron Microscope ◽

Mature Spore ◽

Spore Surface ◽

Sectioned Material ◽

Transmission Electron ◽

Surface Detail

Recent electron microscope studies have greatly expanded our knowledge of the structure of the Microsporida, particularly of the developing and mature spore. Since these studies involved mainly sectioned material, they have revealed much internal detail of the spores but relatively little surface detail. This report concerns observations on the spore surface by means of the transmission electron microscope.

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Surface Structure of Nucleated Animal Cells: Carbon Replicas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060611 ◽

1967 ◽

Vol 25 ◽

pp. 120-121

Author(s):

Robert M. Glaeser ◽

Thea B. Scott

Keyword(s):

Cell Surface ◽

Surface Structure ◽

Particle Diameter ◽

Cellular Functions ◽

Animal Cells ◽

Replica Technique ◽

Carbon Replica ◽

Characteristic Particle ◽

Cell Surface Structure ◽

Carbon Replicas

The carbon-replica technique can be used to obtain information about cell-surface structure that cannot ordinarily be obtained by thin-section techniques. Mammalian erythrocytes have been studied by the replica technique and they appear to be characterized by a pebbly or “plaqued“ surface texture. The characteristic “particle” diameter is about 200 Å to 400 Å. We have now extended our observations on cell-surface structure to chicken and frog erythrocytes, which possess a broad range of cellular functions, and to normal rat lymphocytes and mouse ascites tumor cells, which are capable of cell division. In these experiments fresh cells were washed in Eagle's Minimum Essential Medium Salt Solution (for suspension cultures) and one volume of a 10% cell suspension was added to one volume of 2% OsO4 or 5% gluteraldehyde in 0.067 M phosphate buffer, pH 7.3. Carbon replicas were obtained by a technique similar to that employed by Glaeser et al. Figure 1 shows an electron micrograph of a carbon replica made from a chicken erythrocyte, and Figure 2 shows an enlarged portion of the same cell.

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