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1

The Influence of Pressure on the Roughness of InGaP Layers

100%

Dumiszewska E., Knyps P., Wesolowski M., Teodorczyk M., Strupinski W.

Acta Physica Polonica A

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2011

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vol. 120

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issue 6A

A-50-A-51

EN

Today, the technology of typical silicon-solar cells is fully developed and mature. In spite of its continuous improvements, the record efficiencies of 25.0% are approaching theoretical solar conversion limits of around 33.7%. Values much beyond this limit are likely to be achieved using III-V semiconductor compounds, electrical and optical properties are more suitable for solar energy conversion. They are the most promising candidates for realizing solar cells, which can achieve efficiencies of 50% and more. In this paper we studied the influence of pressure in the reactor chamber on the roughness of an InGaP "nucleation layer" grown on Ge. The growth of the layers was performed in a metalorganic vapour phase epitaxy reactor AIX 200/4. The source gases were trimethylgallium, trimethylindium and AsH_3. The rate of pressure in the reactor was raised from 100 mbar to 400 mbar by 50 mbar. The InGaP layers with the lowest roughness were achieved at the pressure of 400 mbar. The layers were characterized by very low roughness (RMS < 0.3) measured by atomic force microscopy. The quality of the surface was perfect enough to be applied in a solar cell structure.

2

Raman Studies of Defects in Graphene Grown on SiC

86%

Grodecki K., Bożek R., Borysiuk J., Strupinski W., Wysmolek A., Stępniewski R., Baranowski J.

Acta Physica Polonica A

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2011

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vol. 119

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issue 5

595-596

EN

The Raman scattering studies of multi-layer graphene obtained by high temperature annealing of carbon terminated face of 4H-SiC(000-1) substrates are presented. Intensity ratio of the D and G bands was used to estimate the average size of the graphene flakes constituting carbon structures. The obtained estimates were compared with flake sizes from atomic force microscopy data. We found that even the smallest structures observed by atomic force microscopy images are much bigger than the estimates obtained from the Raman scattering data. The obtained results are discussed in terms of different average flake sizes inside and on the surface of the multi-layer graphene structure, as well as different type of defects which would be present in the investigated structures apart from edge defects.

3

X-Ray Photoelectron Spectroscopy - Methodology and Application

73%

Papis-Polakowska E., White R., Deeks C., Mannsberger M., Krajewska A., Strupinski W., Płocinski T., Jankowska O.

Acta Physica Polonica A

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2014

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vol. 125

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issue 4

1061-1064

EN

The crucial measurements aspects of X-ray photoelectron spectroscopy, such as chemical state analysis, depth profiling, mapping, and thickness calculation have been presented. The metal alloys, Ti_2O_5, graphene and type-II InAs/GaSb superlattice structures have been examined by using the new Thermo Scientific K-Alpha X-ray Photoelectron Spectrometer.

4

The sensibility of resistance sensor structures with graphene to the action of selected gaseous media

59%

Opilski Z., Stolarczyk A., Pustelny T., Urbańczyk M., Setkiewicz M., Drewniak S., Maciak E., Procek M., Gut K., Pasternak I., Strupinski W.

Bulletin of the Polish Academy of Sciences: Technical Sciences

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2013

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issue 2

5

The Influence of Humidity on the Resistance Structures with Graphene Sensor Layer

59%

Pustelny T., Setkiewicz M., Drewniak S., Maciak E., Stolarczyk A., Procek M., Urbańczyk M., Gut K., Opilski Z., Pasternak I., Strupinski W.

Acta Physica Polonica A

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2012

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vol. 122

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issue 5

870-873

EN

In the paper the results of investigations are presented concerning the influence of humidity of air on the resistance of a gas sensor structure with a graphene layer. The affects of nitrogen dioxide and humidity action on graphene were studied. We indicated that humidity might play an important role in determining the gas sensing properties of the graphene layer. In the paper it has been shown that in the case of a nitrogen oxide sensor, the reaction of NO_2 with water vapour can generate permanent defects in graphene.

Refine search results

The Influence of Pressure on the Roughness of InGaP Layers

Raman Studies of Defects in Graphene Grown on SiC

X-Ray Photoelectron Spectroscopy - Methodology and Application

The sensibility of resistance sensor structures with graphene to the action of selected gaseous media

The Influence of Humidity on the Resistance Structures with Graphene Sensor Layer