Search

Your search keyword '"Pessa, M."' showing total 1,026 results
Start Over Author "Pessa, M."
1,026 results on '"Pessa, M."'

14. Nitrogen incorporation into GaINAs lattice-matched to GaAs: The effects of growth temperature and thermal annealing

Author

Pavelescu, E.-M., Wagner, J., Komsa, H.-P., Rantala, T.T., Dumitrescu, M., and Pessa, M.

Subjects
Gallium arsenide -- Thermal properties, Indium -- Thermal properties, Raman spectroscopy -- Usage, Nitrogen compounds -- Thermal properties, Physics
Abstract

The effects of growth temperature and subsequent thermal annealing on nitrogen incorporation into lattice-matched dilute Ga0.942In0.058NAs-on-GaAs epilayers are studied. Results reveal the indications of the presence of nitrogen dimers NN in qualitative agreement with the calculations as suggested by Raman spectroscopy.

Published
2005

15. Performance comparison of GaInNAs vertical-cavity semiconductor optical amplifiers

Author

Laurand, N., Calvez, S., Dawson, M. D., Bryce, A. C., Pessa, M., Jouhti, T., and Konttinen, J.

Subjects
Quantum wells -- Research, Image intensifiers -- Research, Light amplifiers -- Research, Indium -- Electric properties, Gallium arsenide -- Electric properties, Business, Computers, Electronics, Electronics and electrical industries
Abstract

The theoretical and experimental investigations of the influence of the number of GaInNAs quantum wells (QWs) on performance of 1.3-mum vertical-cavity semiconductor optical amplifiers (VCSOAs) are reported. Findings reveal that at high-gain and low enough reflectivity, the intrinsic noise figure is smaller than 5 decibel (dB).

Published
2005

23. Annealing of the deep recombination center in GaInP/AlGaInP quantum wells grown by solid-source molecular beam epitaxy

Author

Dekker, J., Tukiainen, A., Xiang, N., Orsila, S., Saarinen, M., Toivonen, M., Pessa, M., Tkachenko, N., and Lemmetyinen, H.

Subjects
Annealing -- Research, Molecular beams -- Research, Photoluminescence -- Usage, Quantum wells -- Research, Semiconductors -- Optical properties, Physics
Abstract

The effect of rapid thermal annealing on bulk GaInp and GaInP/AlGaInP quantum wells grown by solid source molecular beam epitaxy is investigated using deep level transient spectroscopy and time resolved photoluminescence. After the rapid thermal annealing, decreases in the concentration of several deep level traps became apparent. Results also suggest that the defect labeled N3, 0.83 eV, below the conduction band, is the dominant recombination center.

Published
1999

24. ZnSe/GaAs band-alignment determination by deep level transient spectroscopy and photocurrent measurements

Author

Souifi, A., Adhiri, R., Dantec, R. Le, Guillot, G., Uusimaa, P., Rinta-Moykky, A., and Pessa, M.

Subjects
Gallium arsenide -- Research, Diodes, Schottky-barrier -- Research, Physics
Abstract

A study was conducted to analyze Schottky contacts formed on p-isotype Zn(SSe)/GaAs heterostructures prepared by molecular beam epitaxy on p-GaAs(100) substrates. Deep level transient spectroscopy and photocurrent measurements were utilized to carry out the analysis. Results indicated that the threshold energies determined on a series of samples can be explained by absorption processes from the ZnSe and GaAs valence bands.

Published
1999

29. Diffusion of Au in ZnSe and its dependence on crystal quality

Author

Slotte, J., Salonen, R., Ahlgren, T., Rauhala, E., Keinonen, j., raisanen, J., Uusimaa, P., Salokatve, A., Pessa, M., and Laakso, A.

Subjects
Diffusion -- Research, Gold -- Research, Zinc compounds -- Research, Crystals -- Research, Backscattering -- Research, Epitaxy -- Research, Thin films -- Research, Gallium arsenide semiconductors -- Research, Physics
Abstract

A study was conducted to analyze the diffusion of gold in zinc selenide by a 12C and 4H ion backscattering method. Molecular beam epitaxy was carried out to prepare thin films on bulk gallium arsenide (GaAs)(100) substrates and on GaAs(100) epitaxial layers. Topographical data of the sample surfaces were utilized to determine the theoretical Rutherford backscattering spectrometry spectrum. Results indicated that gold diffusion correlated with the crystal quality of zinc selenide.

Published
1999

31. Band offsets at the GaInP/GaAs heterojunction

Author

Lindell, A., Pessa, M., Salokatve, A., Bernardini, F., Nieminen, R.M., and Paalanen, M.

Subjects
Gallium arsenide semiconductors -- Research, Phonons -- Analysis, Physics
Published
1997

36. Aluminum-free 980-nm GaInAs/GaInAsP/GaInP pump lasers

Author

Asonen, Harry, Ovtchinnikov, A., Zhang, Guodong, Nappi, J., Savolainen, P., and Pessa, M.

Subjects
Semiconductor lasers -- Research, Waveguides -- Analysis, Business, Computers, Electronics, Electronics and electrical industries
Abstract

The high-power operation of Al-free pump lasers, whose performance was comparable to that of AlGaAs pump lasers, at 0.98 micrometer wavelength was discussed. The lasing characteristics of these lasers were obtained as functions of waveguide composition. These lasers, whose longitudinal modes were jump-free upto 110 milliwatts output power, achieved 200 mW single-lateral mode operation.

Published
1994

38. Effects of rapid thermal annealing on lasing properties of InGaAs/GaAs/GaInP quantum well lasers

Author

Zhang, G., Nappi, J., Ovtchinnikov, A., Asonen, H., and Pessa, M.

Subjects
Quantum wells -- Research, Semiconductor films -- Research, Semiconductors -- Thermal properties, Physics
Abstract

A study was done on the effects of thermal annealing on lasing properties of InGaAs/GaAs/GaInP quantum well lasers. Results show an increase on the room-temperature photoluminescence of the quantum well and a decrease in the threshold current density of the lasers after rapid thermal annealing. These results were attributed to the elimination of nonradiative centers from the InGaAs/GaAs interfaces.

Published
1992

Catalog

Books, media, physical & digital resources
See catalog results