Wyniki wyszukiwania - BazTech

1

Planarne domieszkowanie krzemem naprężonych studni kwantowych InxGa1-xAs/GaAs w technice MOVPE

Ściana B., Radziewicz D., Paszkiewicz B., Tłaczała M., Sitarek P., Kudrawiec R., Misiewicz J., Kováč J., Florovič M.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 2-3

14-15

PL

Przedstawiono wyniki badań, dotyczące procesów planarnego domieszkowania krzemem naprężonych, pojedynczych studni kwantowych InxGa1-xAs/GaAs w technice MOVPE. Badano wpływ parametrów procesu domieszkowania oraz szerokości studni kwantowej na rozkład domieszki krzemowej. Wprowadzenie domieszki typu delta do studni kwantowej w znaczący sposób zwiększa jej przestrzenne ograniczenie. Ponadto powoduje silną modyfikację przejść optycznych i wzmocniony efekt Starka.

EN

This work presents the studies of Si-δ-doped InxGa1-x As/GaAs strained quantum well obtained by MOVPE technology. The influence of the growth parameters and quantum well width on silicon dopant distribution was investigated. It was shown that introducing delta layer into quantum well gives better carrier confinement. In addition, the PR and PC spectra of Si-δ-doped InxGa1-x As/GaAs SQW confirmed significant modification of the optical transitions and enhanced QCSE.

2

Semiconductor heterostructures and device structures investigated by photoreflectance spectroscopy

Misiewicz J., Sitarek P., Sęk G., Kudrawiec R.

Materials Science

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2003

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Vol. 21, No. 3

263-318

EN

In this review paper, we present the photoreflectance spectroscopy as a powerful tool for investigations of bulk semiconductors and semiconductor heterostructures. We discuss the application of this spectroscopy technique to investigate various properties of semiconductors, including: the composition of multinary compounds, distribution of the built-in electric field and the influence of perturbation such as temperature, strain, pressure; low-dimensional structures such as quantum wells, multiple quantum wells and superlattices, quantum dots; and the structures of semiconductor devices like transistors and vertical/planar light emitting laser structures.

3

Photoreflectance spectroscopy of low-dimensional semiconductor structures

Misiewicz J., Sitarek P., Sęk G.

Opto-Electronics Review

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2000

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Vol. 8, No. 1

1-24

EN

In this paper, we present the applications of photoreflectance spectroscopy for investigations of low-dimensional, semiconductor structures. We briefly introduce the theoretical background of this technique including the line-shape expressions related to semiconductor microstructures. We show examples of photoreflectance investigations of two-dimensional structures such as quantum wells, multiple quantum wells and superlattices, one-dimensional structures-guantum wires, and quasi zero-dimensional structures-quantum dots. Finally, we concentrate our attention on investigations of the structures of semiconductor devices like high electron mobility transistors, heterojunction bipolar transistors and vertical / planar light emitting lasers structures.

4

Technology and characterization of resonant cavity enhanced MSM GaAs photodetectors

Ściana B., Radziewicz D., Zborowska-Lindert I., Boratyński B., Czernecki R., Sitarek P., Misiewicz J., Tłaczała M.

Electron Technology

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2000

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Vol. 33, No. 3

404-407

EN

Design, material growth and characterization of high speed resonant cavity enhanced GaAs MSM photodetector for 0.87 µm were performed. The epitaxial structure was grown by Metal Organic Vapour Phase Epitaxy (MOVPE). A GaAs absorption layer was placed inside a Fabry-Perot resonant cavity formed by a 10 apir AlAs/GaAs quarter-wavelength stack Bragg reflector on the substrate side and the natural semiconductor-air interface on the top side. The quality of the Bragg reflector was examined using a high resolution X-ray diffraction and reflectivity measurements. The Ti/Pd/Au multifinger Schottky contacts were patterned using lift-off photolithographic technique. The current responsivity, spectral chracteristics and optical pulse response of the obtained RCE MSM photodetectors were measured.

5

Spectroscopic properties of CdS nanoparticles embedded in sol-gel silica glasses

Stręk W., Makuszewski K., Jasiorski M., Łukowiak E., Bryja L., Ciorga M., Sitarek P., Misiewicz J.

Optica Applicata

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1999

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Vol. 29, nr 3

401-405

EN

Absorption, emission and excitation spectra of CdS nanoparticles embedded in sol-gel silica glasses are reported. Their manufacturing and morphology are described. The effects of temperature on emission behaviour were investigated.

6

Photoreflectance spectroscopy applied to semiconductors and semiconductor heterostructures.

Misiewicz J., Sęk G., Sitarek P.

Optica Applicata

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1999

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Vol. 29, nr 3

327-363

EN

The photoreflectance spectroscopy is presented as a powerful tool for the characterisation of semiconductor bulk and heterostructures. the advantages and possibilities offered by this electromodulation technique to investigate optical properties of a number of semiconductors and semiconductor structures, on which the modern electronic and optoelectronic devices are based, are reviewed. We discuss the application of the photoreflectance spectroscopy to study various properties of semiconductors, including the composition of multinary semiconducting compounds, carrier concentration, characteristic lifetimes of carriers, energies of trap states, distribution of the built-in electric field in home- and heterostructures, the influence of perturbations such as temperature, strain and effects of growth processing and annealing.

7

Photoreflectance spectroscopy of strained Si1-xGex/Si epilayers

Sitarek P., Misiewicz J., Nauka K.

Electron Technology

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1998

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Vol. 31, No. 3/4

409-410

EN

Si1-xGex epilayers with germanium composition up to 25% have been studied by photoreflectance spectroscopy. All sprectra were obtained at room temperature with He-Ne laser as the pumping source. Aspne's analytical formula applied to the PR spectra allowed us to determine the optical transtion energies. The observed transitions were identified as E1 and E'0 ( E1+∆1) direct transitons at Si1-xGex layers were analyzed in terms of the changes of the optical transition energies comparing to unstrained material.

8

CdTe/Cd1-xMnxTe quantum structures investigated by photoreflectance spectroscopy

Sitarek P., Misiewicz J., Karczewski G., Wójtowicz T., Kossut J.

Electron Technology

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1998

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Vol. 31, No. 3/4

311-314

EN

Room temperature photoreflectance spectroscopy was used to investigate Cd1-xMnxTe/CdTe quantum structures grown by MBE technique. The system of four quantum wells of x = 0.28 with different thicknesses was under study first. The obtained spectrum showed a series of resonances which are attributed to the intersubband transitions. The second group of quantum structures were CdTe/Cd1-xMnxTe MQW. The samples were δ-doped in the middle of the wells by using indium. Transitions related to heavy holes in δ-doped wells were found to occur at different energies thaqn those in undoped wells. The influence of the strains on (CdMn)Te/CdTe quantum stryctures has been taken into account.