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Article
Publication date: 3 August 2010

A.F. Abd Rahim, M.R. Hashim and N.K. Ali

The purpose of this paper is to describe a very low‐cost way to prepare Ge nano/microstructures by means of filling the material inside porous silicon (PS) using a conventional…

Abstract

Purpose

The purpose of this paper is to describe a very low‐cost way to prepare Ge nano/microstructures by means of filling the material inside porous silicon (PS) using a conventional and cost effective technique in which thermal evaporator with PS acts as patterned substrate. Also, the potential metal‐semiconductor‐metal (MSM) photodetector IV characteristics of the structure are demonstrated.

Design/methodology/approach

PS was prepared by anodization of Si wafer in ethanoic hydrofluoric acid. The Ge layer was then deposited onto the PS by thermal evaporation. The process was completed by Ni metal deposition using thermal evaporator followed by metal annealing of 400°C for 10 min. Structural analysis of the samples was performed using energy dispersive X‐ray analysis (EDX), scanning electron microscope (SEM), X‐ray diffraction (XRD) and Raman spectroscopy.

Findings

A uniform circular network distribution of pores is observed with sizes estimation of 100 nm to 2.5 μm by SEM. Also observed are clusters with near spherical shape clinging around the pores believed to be Ge or GeO2. The EDX spectrum suggests the presence of Ge or GeO2 on and inside the pore structure. Raman spectrum showed that good crystalline structure of the Ge can be produced inside the silicon pores. XRD showed the presence of a Ge phase with the diamond structure by (111), (220), and (400) reflections. Finally, current‐voltage (I‐V) measurement of the Si/Ge/PS MSM photodetector was carried out. It showed lower dark currents compared to control device of Si. The device showed enhanced current gain compared to conventional Si device which can be associated with the presence of Ge nanostructures in the PS.

Originality/value

This paper shows that it is possible to grow Ge nano/microstructure on PS by using a simple and low‐cost method of thermal evaporation and thermal annealing and demonstrates potential MSM photodetector IV characteristics from the device.

Details

Microelectronics International, vol. 27 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 5 March 2010

Keiji Houjou, Kotoji Ando and Koji Takahashi

Zirconia ceramics exhibit high strength and fracture toughness. The purpose of this paper is to research a possibility of crack healing in zirconia ceramics.

Abstract

Purpose

Zirconia ceramics exhibit high strength and fracture toughness. The purpose of this paper is to research a possibility of crack healing in zirconia ceramics.

Design/methodology/approach

ZrO2/SiC composite ceramics are sintered and subjected to three‐point bending. A surface crack of 100 μm in diameter is formed on each specimen. The cracks are healed and the specimens are tested under bending.

Findings

The paper finds that ZrO2/SiC composite ceramic material had a high crack‐healing ability at a considerably low temperature. For example, a crack of 100 μm in diameter is healed even at 600°C.

Research limitations/implications

The paper provides a low temperature healing and a new mechanism of crack healing.

Originality/value

The paper shows the healing temperature and the minimum time required to heal showed a good proportional relation on the Arrhenius plot at temperatures of 600‐800°C. Moreover, the crack healing is caused by SiO2 cristobalite produced during the healing.

Details

International Journal of Structural Integrity, vol. 1 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 June 2005

B. Klapiszewska, A. Krysztafkiewicz and T. Jesionowski

The study reported here concerned production of green pigments, hydrated nickel(II) silicates and oxides, obtained by precipitation from solutions of sodium metasilicate and…

Abstract

Purpose

The study reported here concerned production of green pigments, hydrated nickel(II) silicates and oxides, obtained by precipitation from solutions of sodium metasilicate and sodium hydroxide using nickel(II) sulphate.

Design/methodology/approach

The pigments were analysed using a number of techniques including scanning electron microscopy for particle surface morphology and dynamic light scattering for particle structure and the tendency of the particles to agglomerate.

Findings

The most desirable physicochemical parameters were shown by highly dispersed nickel(II) silicates precipitated in presence of the modifying agents. Silicate pigments precipitated in the presence of Rokanol K‐7 had low bulk densities, a high capacity to absorb water, dibutyl phthalate and paraffin oil within the primary particles, which is particularly noteworthy.

Practical implications

Due to their good dispersibility, well developed surface and appropriate coating power, coloured silicates of, e.g. chromium(III) and nickel(II) may be used as pigments and fillers for surface coatings.

Originality/value

The method of obtaining nickel(II) pigments developed was novel and provided a solution for problem of post‐galvanic nickel solutions.

Details

Pigment & Resin Technology, vol. 34 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 10 December 2020

Zhenrong Zheng, Lingli Ren, Peng Huang and Xiaoming Zhao

The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

Abstract

Purpose

The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

Design/methodology/approach

The silicone resin with excellent heat resistance was selected as the base solution. Silica nanoparticles, mica powder and ferric oxide were added into the coating solution, which was coated on the glass fiber fabrics. The vertical burning, thermal protective performance (TPP) value, second-degree burn time and water repellency of the coated fabrics were characterized.

Findings

Results showed that the dosages of the thickening filler were in the range 4%–6%; the coating solution has good viscosity. The optimal composition of fillers added in the silicone resin is silica nanoparticles 6%, ferric oxide 5% and mica powder 6%. The TPP value of the optimum coated fabric is 413 kW·s/m2. The second-degree burn time is 4.98 s, which is obviously higher than that of the original glass fiber fabric (3.49 s) and that of the aramid fabric (3.82 s). The coated fabric has better thermal stability than aramid fabric.

Originality/value

The production cost of this coated glass fiber fabric was much lower than that of the aramid fabric.

Details

Pigment & Resin Technology, vol. 50 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 February 1991

A.K. Bhattamishra, G.S. Mishra and M.K. Banerjee

Iron and silicon are the two inherent impurities present in commercial aluminium which impair its corrosion resistance. Influence of silicon/iron ratio present in aluminium alloys…

Abstract

Iron and silicon are the two inherent impurities present in commercial aluminium which impair its corrosion resistance. Influence of silicon/iron ratio present in aluminium alloys containing different amounts of silicon has been studied through electrochemical polarization in some inorganic and organic acids (0.1 N). It has been observed that Si/Fe ratio has potential role on corrosion rates in different acids studied.

Details

Anti-Corrosion Methods and Materials, vol. 38 no. 2
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 December 1998

Hans Mayer

An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

1587

Abstract

An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

Details

Pigment & Resin Technology, vol. 27 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Content available
Article
Publication date: 3 July 2007

56

Abstract

Details

Sensor Review, vol. 27 no. 3
Type: Research Article
ISSN: 0260-2288

Article
Publication date: 1 February 1965

MICHAEL BASSEY B.Sc. Ph.

PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses of the…

Abstract

PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses of the three GCE Boards previously discussed are analysed.

Details

Education + Training, vol. 7 no. 2
Type: Research Article
ISSN: 0040-0912

Article
Publication date: 21 November 2008

Ehsan Saeedi, Samuel Kim and Babak A. Parviz

The paper's aim is to present a method for integrating high‐performance circuit components onto flexible substrates using self‐assembly. The basic process of self‐assembly at the…

Abstract

Purpose

The paper's aim is to present a method for integrating high‐performance circuit components onto flexible substrates using self‐assembly. The basic process of self‐assembly at the micrometer‐scale is reviewed and recent work in building functional parts such as silicon transistors and compound semiconductor light emitting diodes, as well as their integration onto flexible plastic templates, is reported.

Design/methodology/approach

A micron‐scale self‐assembly method was used for building flexible circuits. In micron‐scale self‐assembly, functional micro‐components are independently microfabricated and subsequently allowed to self‐assemble on a template with electrical interconnects and corresponding binding sites in a fluid.

Findings

The self‐assembly process can achieve heterogeneous integration with a potentially very high yield. Successful assembly of functional micro‐components such as LEDs and transistors on plastic has been demonstrated.

Originality/value

The paper demonstrates fabrication techniques for free‐standing micro‐components with novel designs, low‐temperature fabrication on thin plastic sheets, and using capillary‐gravity‐based self‐assembly for the integration of crystalline inorganic semiconductor components onto unconventional substrates such as flexible polymers.

Details

Circuit World, vol. 34 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 27 July 2018

Walaa M. Abd El-Gawad and Nivin M. Ahmed

The purpose of this paper is to prepare new economical thermal resistant coatings containing white sand (WS) and kaolin (K) fillers, which are cheap natural ores in Egypt and are…

Abstract

Purpose

The purpose of this paper is to prepare new economical thermal resistant coatings containing white sand (WS) and kaolin (K) fillers, which are cheap natural ores in Egypt and are sources for ceramic materials such as SiO2 and Al2O3.

Design/methodology/approach

This paper investigates the effect of heat at 500°C on the durability of mild steel samples coated with silicon coatings. The coated plates were exposed to elevated temperatures according to ASTM D 2485 to determine their stability. Thermal gravimetric analysis and scanning electron microscopy were used to investigate the thermal stability of the modified films.

Findings

It was revealed that the composite fillers can enhance the thermal stability of silicon coatings. Another advantage of using the prepared composite fillers is promoting the dryness of silicon resin without heat.

Research limitations/implications

Different natural ores were used as ceramic filler to enhance the thermal stability of silicon coatings.

Originality/value

New economical thermal-resistant coatings containing white sand and kaolin were prepared to replace the expensive thermal coatings; also, they can be used in industries other than coatings, e.g. paper, rubber and plastics composites.

1 – 10 of 404