Institute of Microelectronics and Optoelectronics

Warsaw, Poland

Institute of Microelectronics and Optoelectronics

Warsaw, Poland
SEARCH FILTERS
Time filter
Source Type

Lukasiak L.,Institute of Microelectronics and Optoelectronics | Jasinski J.,Institute of Microelectronics and Optoelectronics | Jakubowski A.,Institute of Microelectronics and Optoelectronics
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

Reverse current of GaN vertical Schottky diodes is simulated using Silvaco ATLAS to optimize the geometry for the best performance. Several physical quantities and phenomena, such as carrier mobility and tunneling mechanism are studied to select the most realistic models. Breakdown voltage is qualitatively estimated based on the maximum electric field in the structure. © 2016 SPIE.


Lukasiak L.,Institute of Microelectronics and Optoelectronics | Jasinski J.,Institute of Microelectronics and Optoelectronics | Beck R.B.,Institute of Microelectronics and Optoelectronics | Ikraiam F.A.,Omar Al-Mukhtar University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

This paper presents a model of high frequency capacitance of a SOI MOSCAP. The capacitance in strong inversion is described with minority carrier redistribution in the inversion layer taken into account. The efficiency of the computational process is significantly improved. Moreover, it is suitable for the simulation of thin-film SOI structures. It may also be applied to the characterization of non-standard SOI MOSCAPS e.g. with nanocrystalline body. © 2016 SPIE.


Wielgus M.,Polish Institute of Electron Technology | Wielgus M.,Institute of Micromechanics and Photonics | Grochowski J.,Polish Institute of Electron Technology | Grochowski J.,Institute of Microelectronics and Optoelectronics | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

We present a novel application of the continuous wavelet transform (CWT) for quantitative analysis of electron diffraction fringe patterns for material science research. With this method unsupervised analysis of large data sets can be performed, to determine statistical distribution of fringe periods, corresponding to the spacing between the planes in the atomic lattice. It is more robust and less time consuming than typical manual approach. Obtained information can be further utilized for characterization and identification of the crystallographic structures present in the sample. The proposed method is applied to analysis of high resolution transmission electron microscope (HRTEM) images of Iridium-Zinc-Silicon-Oxide thin films, which reveal nanocrystallic structures dispersed in an amorphous matrix. © 2012 SPIE.


Malinowski M.,Institute of Microelectronics and Optoelectronics | Kaczkan M.,Institute of Microelectronics and Optoelectronics | Turczynski S.,Institute Of Electronic Materials Technology of Poland | Pawlak D.,Institute Of Electronic Materials Technology of Poland
Optical Materials | Year: 2011

Concentration dependant emission spectra and fluorescence dynamic profiles have been investigated in PrxLa1-xAlO 3 single crystals in order to better understand processes responsible for concentration quenching of the praseodymium 3P0 and 1D2 emissions. The cross-relaxation transfer rates were experimentally determined as a function of Pr3+ concentration. Decays were modeled and nearest-neighbor trapping rates were calculated. © 2010 Elsevier B.V. All rights reserved.


Drozdowski W.,Nicolaus Copernicus University | Brylew K.,Nicolaus Copernicus University | Malinowski M.,Institute of Microelectronics and Optoelectronics | Turczynski S.,Institute Of Electronic Materials Technology of Poland
Journal of Alloys and Compounds | Year: 2015

Y4Al2O9:Pr (YAM:Pr) crystals have been grown by the micro-pulling-down method and their scintillation properties have been investigated. YAM:0.1%Pr displays a light yield of about 2000 ph/MeV and its scintillation time profile contains a prompt component with a decay time of 23.5 ns and a contribution of 20%. Radioluminescence spectra show both fast d-f and slow f-f praseodymium emissions. Low temperature glow curves are complex, consisting of discrete peaks and broad bands related to quasi-continuous trap distributions. Overall scintillation performance of YAM:Pr deteriorates with increasing praseodymium concentration. © 2015 Elsevier B.V. All rights reserved.


Zawistowski J.,Institute of Microelectronics and Optoelectronics | Kurzejamski G.,Lingaro Sp. Z O.o. | Garbat P.,Institute of Microelectronics and Optoelectronics | Naruniec J.,Institute of Radioelectronics and Multimedia Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

This paper presents a system designed for the multi-object detection purposes and adjusted for the application of product search on the market shelves. System uses well known binary keypoint detection algorithms for finding characteristic points in the image. One of the main idea is object recognition based on Implicit Shape Model method. Authors of the article proposed many improvements of the algorithm. Originally fiducial points are matched with a very simple function. This leads to the limitations in the number of objects parts being success- fully separated, while various methods of classification may be validated in order to achieve higher performance. Such an extension implies research on training procedure able to deal with many objects categories. Proposed solution opens a new possibilities for many algorithms demanding fast and robust multi-object recognition. © 2016 SPIE.


Malinowski M.,Institute of Microelectronics and Optoelectronics | Kaczkan M.,Institute of Microelectronics and Optoelectronics | Turczynski S.,Institute Of Electronic Materials Technology of Poland
Optical Materials | Year: 2016

Sm3+ doped YAlO3 (YAP) single crystals were prepared by the micro-pulling down method. Emission spectra as well as luminescence decay curves for these crystals were recorded at temperatures ranging from 10 K to 300 K. Based on the low temperature spectra the energies of the Stark levels for several multiplets were determined. The fluorescence decay curves have been measured as a function of concentration and temperature and are found to exhibit single exponential nature at lowest concentration of 0.1 at.% but are strongly non-exponential at concentrations above 1 at.%. This concentration quenching of the Sm3+ ion emission was ascribed to resonant cross-relaxation. The non-exponential decay rates were successfully fitted to Inokuti-Hirayama model for s = 6 indicating that the nature of the energy transfer process among the Sm3+ ions is of electric dipole-dipole type. Cross-relaxation rates were experimentally determined as a function of activator concentration and used to evaluate and to model the decays. The critical distances and energy transfer microparameter for the transfer processes were given.After pulsed 925-975 nm infra-red excitation upconverted yellow-orange emission has been generated at room temperature in Sm3+:YAP crystals. Dynamics of the involved excited states have been analyzed and the responsible upconversion mechanism was proposed to be energy transfer. © 2016.


Kaczkan M.,Institute of Microelectronics and Optoelectronics | Boruc Z.,Institute of Microelectronics and Optoelectronics | Fetlinski B.,Institute of Microelectronics and Optoelectronics | Turczynski S.,Institute Of Electronic Materials Technology of Poland | Malinowski M.,Institute of Microelectronics and Optoelectronics
Applied Physics B: Lasers and Optics | Year: 2013

Temperature-dependent emission spectra and fluorescence dynamics profiles have been investigated in Pr3+:Y4Al2O 9 crystals in order to better understand the processes responsible for quenching of the praseodymium 3P0 emissions. The cross-relaxation transfer rates were experimentally determined as a function of temperature. Using the rate equations formalism, the dynamics of the observed emissions were modeled. Basing on comparison between the measured and calculated decays, the energy transfer rates between Pr3+ ions were evaluated. The role of the backward process in explanation of the complicated character of 3P0 decays and its temperature dependence, especially its unexpectedly slow decaying component, were established. © 2013 The Author(s).


Boruc Z.,Institute of Microelectronics and Optoelectronics | Kaczkan M.,Institute of Microelectronics and Optoelectronics | Fetlinski B.,Institute of Microelectronics and Optoelectronics | Turczynski S.,Institute Of Electronic Materials Technology of Poland | Malinowski M.,Institute of Microelectronics and Optoelectronics
Optics Letters | Year: 2012

Temperature dependent emission spectra and decay times of trivalent dysprosium (Dy3+) activated Y4Al2O9 (YAM) crystals have been studied for the first time (to our knowledge). The ratio of emission lines intensity can be used in temperature measurements, as it is not dependent on the variability of absolute intensity. The Boltzmann model was applied for modeling the temperature variation of the 4I 15/2 and 4F9/2 states emissions relative intensities 455 and 481 nm, respectively. The calculated approximation gives highest sensor sensitivity of about 3 × 10-3°C-1 for the 600°C-800°C range, which allows for an expectation of usefulness of Dy3+:YAM in high-temperature luminescence thermometry. Also, the measured decay times are suitable for temperature sensing. © 2012 Optical Society of America.


Yang L.,Institute of Microelectronics and Optoelectronics | Hu T.,Zhejiang University | Shen A.,Zhejiang University | Pei C.,Zhejiang University | And 5 more authors.
IEEE Photonics Technology Letters | Year: 2014

We propose a new method to change the resonant status of the microring by modifying the light-absorption ability of the waveguide. A conception of a 2 × 2 microring switch based on the graphene-silicon-waveguide is presented by inserting a single graphene flake inside the lateral slot waveguide. The resonance procedure of the microring is thoroughly blocked when the graphene is tuned to be a zero-permittivity material, which significantly enhances the waveguide's loss. Neither a high quality factor nor a large driving voltage of the microring is needed. According to the numerical analysis, an extinction ratio for > 50 dB is obtained in the drop port with a broad bandwidth. The extinction ratio in the through port is 34 dB. The radius of the microring is 5.1 μm and the driving voltage is 2.38 V. © 2013 IEEE.

Loading Institute of Microelectronics and Optoelectronics collaborators
Loading Institute of Microelectronics and Optoelectronics collaborators