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Characterization of deep-level defects in GaNAs/GaAs heterostructures grown by APMOVPE

Gelczuk Ł., Dąbrowska-Szata M., Ściana B., Pucicki D., Radziewicz D., Kopalko K., Tłaczała M.

Materials Science Poland

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2016

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Vol. 34, No. 4

726--734

EN

Conventional deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS techniques were used to study electrical properties of deep-level defects in dilute GaNAs epitaxial layers grown by atmospheric-pressure metalorganic vapourphase epitaxy (APMOVPE) on the GaAs substrate. Three samples with nitrogen concentrations of 1.2 %, 1.6 % and 2.7 % were investigated. In DLTS and LDLTS spectra of the samples, four predominant electron traps were observed. On the basis of the obtained electrical parameters and previously published results, one of the traps was associated with N-related complex defects, while the other traps with common GaAs-like native defects and impurities, called EL6, EL3 and EL2.

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AP-MOVPE Technology and Characterization of InGaAsN p-i-n Subcell for InGaAsN/GaAs Tandem Solar Cell

Dawidowski W., Ściana B., Zborowska-Lindert I., Mikolásek M., Latkowska M., Radziewicz D., Pucicki D., Bielak K., Badura M., Kováč J., Tłaczała M.

International Journal of Electronics and Telecommunications

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2014

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Vol. 60, No. 2

151-156

EN

Tandem (two p-n junctions connected by tunnel junction) and multijunction solar cells (MJSCs) based on AIIIBV semiconductor compounds and alloys are the most effective photovoltaic devices. Record efficiency of the MJSCs exceeds 44% under concentrated sunlight. Individual subcells connected in series by tunnel junctions are crucial components of these devices. In this paper we present atmospheric pressure metal organic vapour phase epitaxy (AP-MOVPE) of InGaAsN based subcell for InGaAsN/GaAs tandem solar cell. The parameters of epitaxial structure (optical and electrical), fabrication process of the test solar cell devices and current-voltage (J-V) characteristics are presented and discussed.

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Technology and characterisation of GaAsN/GaAs heterostructures for photodetector applications

Ściana B., Zborowska-Lindert I., Pucicki D., Boratyński B., Radziewicz D., Tłaczała M., Serafińczuk J., Poloczek P., Sęk G., Misiewicz J.

Opto-Electronics Review

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2008

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Vol. 16, No. 1

1-7

EN

The nitrogen-containing AIIIBV semiconductor alloys, so-called diluted nitrides (AIIIBV-N, have been extensively studied recently. Unusual properties of these materials make them very promising for applications in lasers and very efficient multijunction solar cells. This work presents the technology and properties of undoped GaAs1-xNxGaAs heterostructures used as active regions in the construction of metal-semiconductor-metal (MSM) photodetectors. The atmospheric pressure metal organic vapour phase epitaxy (APMOVPE) was applied for growing MSM test structures. Their structural and optical properties were examined using high resolution X-ray diffraction (HRXRD), photoluminescence (PL), and photoreflectance spectroscopy (PR). Chemical wet etching was applied for forming an active region and a multifinger Schottky metallization was used as MSM contacts. Dark and illuminated current-voltage characteristics were measured. Based on the obtained results, the main detector parameters as responsivity and spectral response were estimated.

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Technology and properties of GaAs doping superlattices

Ściana B., Radziewicz D., Pucicki D., Tłaczała M., Sęk G., Poloczek P., Misiewicz J., Kováč J., Srnanek R., Christofi A.

Materials Science Poland

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2008

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Vol. 26, No. 1

71--78

EN

Heterojunction and doping superlattices are widely used in many advanced semiconductor devices such as resonant tunnelling diodes, optical modulators, cascade lasers, tunable light emitting diodes and photodetectors. These structures exhibit nonlinear electrooptical properties. Nonlinear processes are governed by the Franz-Keldysh effect and the band-filling effect in the n-i-p-i superlattices and by the quantum-confined Stark effect in the case of n-i-p-i multiple quantum well structures. The paper presents investigations of GaAs n-i-p-i and p-i-p-i doping superlattices grown by atmospheric pressure metal organic vapour phase epitaxy. The properties of the obtained structures were examined using: EC-V method, SIMS spectrometry, photoluminescence and photoreflectance spectroscopy.

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Submicron suspended structures based on A(III)B(V) epitaxial layers

Kramkowska M., Szyszka A., Ściana B., Zubel I.

Materials Science Poland

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2008

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Vol. 26, No. 1

173--179

EN

A technological process has been described for fabrication of suspended structures on GaAs substrate with AlGaAs/GaAs epitaxial multi-layers deposited by the AP MOVPE method. The patterns of beams and bridges with various dimensions were made by the photolithography method. The structures were fabricated by wet chemical etching in two systems of solutions based on phosphoric or citric acid with hydrogen peroxide. The former one enabled etching through the deposited epitaxial layers down to the GaAs substrate. The latter one allowed a selective etching of GaAs over AlGaAs. In effect, a beam made of AlGaAs layer was released and formed the suspended structure. As an etching mask, AZ 1813 positive photoresist was used. A series of rectangular beams with various planar dimensions and submicrometer thicknesses was fabricated. The elaborated process may be used for fabrication of suspended structures for various applications.