Wyniki wyszukiwania - BazTech

1

Stability of ZnO nanofibers in processing liquid agents

Stafiniak A., Boratyński B., Fronc K., Elbaum D., Paszkiewicz R., Tłaczała M., Baranowska-Korczyc A.

Materials Science Poland

|

2013

|

Vol. 31, No. 3

312--317

EN

The aim of the research was to determine the impact of developers, removers and solvents on the stability of ZnO nanofibers. Surface imaging of nanofiber morphology was studied using Scanning Electron Microscope. From the obtained results a set of factors which have the least inﬂuence on the etching of ZnO nanofibers during device processing was selected. The dependence of the grains size on the fibers robustness in the liquid solutions was investigated. It was found that the nanofibers calcinated at higher temperatures were more stable. This was due to the grain size of the fiber as the fibers calcinated at higher temperatures revealed larger grain size. The studies have shown that smaller grains were dissolved much faster, leaving the porous core of the ZnO nanofiber.

2

Parametry detektorów MSM wykorzystujących heterostruktury GaAsN/GaAs i MQW InGaAsN/GaAs

Zborowska-Lindert I., Ściana B., Pucicki D., Radziewicz D., Boratyński B., Tłaczała M.

Elektronika : konstrukcje, technologie, zastosowania

|

2012

|

Vol. 53, nr 2

52-54

PL

W artykule przedstawione zostały parametry fotodetektorów MSM wykonanych na warstwach czynnych GaAsN/GaAs i MQW InGaAsN/GaAs. Wszystkie warstwy czynne optycznie wykonane zostały w technologii epitaksji MOVPE. W warstwach GaAsN/GaAs struktura czynna GaAsN miała grubość 100...330 nm, a zawartość atomów azotu mieściła się w zakresie 0,85...2,2%. Struktury MQW InGaAsN/GaAs stanowiły trzy studnie InGa-AsN o grubości 15 nm i zawartości 11% indu rozdzielone barierami GaAs o grubości 30 nm. W pracy przedstawiono charakterystyki prądowo-napięciowe detektorów MSM bez i z oświetleniem, co pozwala określić podstawowe parametry wykonanych fotodetektorów. Z uzyskanych wyników widać bardzo wyraźny wpływ składu materiałowego wykonanych heterostruktur na fotoprąd i czułość wykonanych fotodetektorów MSM.

EN

In this paper the comparison of GaAsN/GaAs and InGaAsN/GaAs MSM photodetectors has been presented. All of the devices were made by MOVPE technology. The GaAsN/GaAs MSM devices were made on undoped GaAsN layers with concentration of nitrogen varied from 0.85...2.2%. The thickness of these layers was from 100...330 nm. The InGaAsN/GaAs active layer for MSM detectors consisted of triple InGaAsN MQW with 11% of indium in 15 nm thick QWs layers and 30 nm thick GaAs barrier layers. The dark and illuminated l-V characteristics of the designed devices were presented. The photoresponse characteristics have shown a strong influence of material composition on the MSM photocurrent for both GaAsN/GaAs and InGaAsN/GaAs heterostructures.

3

Weryfikacja stałoprądowego modelu tranzystora typu MAGFET

Kordalski W., Pribbenow M., Panek M., Boratyński B., Woźniak J., Zborowska-Lindert I., Ściana B.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

|

2008

|

T. 16

513-518

PL

Zaproponowano kompletny, stałoprądowy model tranzystora typu MAGFET wykorzystywanego jako czujnik pola magnetycznego. Zaprezentowany model odzwierciedla zależność podziału prądu płynącego w kanale tranzystora na prądy drenów od napięć drenów.

EN

A complete DC MAGFET model and its verification is presented. The proposed model takes into account a phenomenon of the source current division into two drain terminal currents.

4

Modelowanie numeryczne nowego czujnika pola magnetycznego

Panek M., Kordalski W., Ściana B., Zborowska-Lindert I., Boratyński B.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

|

2008

|

T. 16

301-304

PL

W pracy przedstawiono analizę numeryczną nowego czujnika pola magnetycznego, którego struktura różni się od znanych MOS MAGFET-ów horyzontalnym, a nie pionowym podziałem drenów. Analizowano wpływ rozmiarów kanału w dwudrenowej strukturze MESFET wykonanej z GaAs na zmiany prądu drenu wywołane polem magnetycznym. Dla wybranej topologii struktury wykonano serię dwuwymiarowych symulacji zjawisk transportu nośników ładunku w kanale tranzystora dla dwóch przypadków: braku i obecności pola magnetycznego. Pozwoliło to uzyskać zarówno stałoprądowe charakterystyki elementu jak i określić wpływ parametrów konstrukcyjnych tranzystora na jego czułość na pole magnetyczne.

EN

2D simulation of a GaAs MAGFET was performed. An impact of the channel geometry, source and split-drain contacts configuration on the magnetic field sensitivity was investigated. Sensitivity of 8%T[to -1] was obtained, and its dependence on the magnetic flux direction was evaluated.

5

Małosygnałowy model tranzystora typu MAGFET

Kordalski W., Damaszk L., Boratyński B., Panek M., Woźniak J., Zborowska-Lindert I., Ściana B.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

|

2008

|

T. 16

501-506

PL

Wyprowadzono małosygnałowy model tranzystora typu MAGFET pracującego jako czujnik pola magnetycznego, w którym uwzględniono wzajemne oddziaływanie napięć drenów. Wykorzystując nowoopracowany model obliczono czułość napięciową typowego układu pracy MAGFET-a na pole magnetyczne.

EN

Small-signal model for the MAGFET, in which mutual interaction between drain voltages is taken into account, is derived and a discussion of obtained results is presented.

6

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

|

2008

|

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.

7

Properties and estimated parameters of a submicrometer HSDMAGFET

Kordalski W., Boratyński B., Panek M.

Materials Science Poland

|

2008

|

Vol. 26, No. 1

33--43

EN

Main features and predicted values of key parameters of a novel magnetic field sensitive semiconductor device, horizontally-split-drain magnetic field sensitive field effect transistor (HSDMAGFET) which can be used to measure or detect steady or variable magnetic fields have been presented. Operating principle of the transistor is based on one of the galvanomagnetic phenomena and the gradual channel detachment effect (GCDE). The predicted relative sensitivity of the sensor can reach as high value as 100 [%/T]. Furthermore, due to its original structure, the spatial resolution of the MAGFET is extremely high, which makes this device particularly useful in reading magnetically encoded data or magnetic pattern recognition. Besides, a novel device related to the HSDMAGFET, namely, horizontally-split-drain current controlled field effect transistor (HSDCCFET) has been presented.

8

A new drain insulation design in GaAs SD-MAGFET

Boratyński B., Kordalski W., Ściana B., Panek M., Zborowska-Lindert I.

Materials Science Poland

|

2008

|

Vol. 26, No. 1

27--21

EN

A new design of a split-drain MAGFET type magnetic sensor based on GaAs MESFET device with a sandwich-like drain configuration has been investigated. An excellent performance of the sensor, namely its high sensitivity and spatial resolution to magnetic field could be obtained as a result of an extremely short (200 nm) distance between the transistor drains realized using a unique epitaxial layer structure. A proper sequence of the AlGaAs/GaAs/AlAs/GaAs epitaxial layers grown by MOCVD technique followed by selective etching process has been proposed and realized. Structural parameters of the layers were studied. Electrical performance of the insulated drain structure was evaluated by measurements of the leakage current that was less than 10 nA for 2 V drain voltage bias difference.

9

Stałoprądowy model tranzystora typu HSD MAGFET

Kordalski W., Boratyński B., Panek M., Polowczyk M., Zborowska-Lindert I., Ściana B., Szymański K., Woźniak J.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

|

2007

|

T. 14

665-674

PL

Zaproponowano stałoprądowy model dwudrenowego tranzystora polowego typu HSD MAGFET, wykorzystywanego jako czujnik pola magnetycznego o dużej czułości na zmiany pola magnetycznego i dużej geometrycznej rozdzielczości pomiarowej. Zaprezentowany model odzwierciedla zjawiska podziału prądu płynącego w kanale tranzystora na prądy drenów i uwzględnia wzajemne oddziaływanie napięć drenów VDS1 i VDS2 na prądy drenów ID1 i ID2 poprzez wprowadzenie funkcji podziału prądu źródła tranzystora.

EN

An analytical self-consistent DC model of a horizontally split-drain magnetic field-effect transistor (HSD MAG-FET) bas been elaborated. The MAGFET-type sensors ale known and valued because of their high magnetic field sensitivity and high measurement spatial resolution. The proposed model takes into account a phenomenon of the source current division into two drain terminal currents. In the model, a mathematical function of the transistor current splitting, based on the drain currents magnitudes, ID1 and ID2 dependency on the drain bias voltages, VDS1 and VDS2 is introduced and explained.

10

Technology and characterization of p-i-n photodetectors with DQW (In,Ga)(As,N)/GaAs active region

Pucicki D., Zborowska-Lindert I., Ściana B., Radziewicz D., Boratyński B.

Optica Applicata

|

2007

|

Vol. 37, nr 4

415-421

EN

Double quantum well (DQW) (In,Ga)(As,N)/GaAs p-i-n photodetectors, grown by solid source molecular beam epitaxy using a radio-frequency plasma source for nitrogen with absorption for wavelengths above 870 nm have been investigated. The active region of the photodetectors contained two very thin absorption layers: 10.5 nm Ga(As,N) (structure #DP02) or 4 nm (In,Ga)(As,N) (#DP03). In spite of this, photodetectors exhibited high sensitivity (0.0525 A/W for 980 nm) for wavelength greater than the absorption edge of GaAs (870 nm). The dark current of photodetectors did not exceed 0.1 žA.

11

Opracowanie technologii i konstrukcji tranzystorów HFET oraz diod Schottky'ego na bazie heterostruktur AIII-N/SiC, przeznaczonych do pracy w zakresie b.w.cz.

Tłaczała M., Paszkiewicz R., Paszkiewicz B., Boratyński B.

Elektronika : konstrukcje, technologie, zastosowania

|

2006

|

Vol. 47, nr 9

16-20

PL

Przedstawiono ofertę grupy badawczej Wydziału Elektroniki Mikrosystemów I Fotoniki Politechniki Wrocławskiej, kierowanej przez Marka Tłaczałę, na opracowanie technologii i konstrukcji tranzystorów HFET i diod Schottky'ego na bazie heterostruktur AIII-N/SiC, przeznacz-nych do pracy w zakresie b.w.cz. Omówiono główne założenia i cele projektu. Przedstawiono oczekiwane rezultaty jego realizacji. Pokazano uwarunkowania technologiczne (urządzenia i laboratoria) oraz oprogramowanie i techniki charakteryzacji umożliwiające podjęcie realizacji projektu.

EN

This paper presents the offer formulated by research group of the Faculty of Microsystem Electronics and Photonic of Wroclaw University of Technology, headed by Marek Tłaczala, for the design of technology and fabrication process of AIII-N/SiC heterostructures HFET transistors and Schottky diodes for microwave application. The main assumption and goals of the project are given. The anticipated results are discussed. The main technological facilities (systems and clean rooms) as well as the software and measurements techniques intended for the realization of the project are presented.

12

Design of a GaN UV integrated photoreceiver

Wiatrowski A., Boratyński B.

Opto-Electronics Review

|

2004

|

Vol. 12, No. 1

165--168

EN

A design of the structure of an integrated GaN photoreceiver for the UV range is presented. The circuit includes an MSM photodetector and an HFET based amplifier. Preliminary data for the design were obtained from the measurements performed on the test structures - CTLM, van der Pauw, Schottky contacts and also performed on discrete devices - MSM detectors, HFET transistors - all fabricated on AlGaN/GaN/sapphire substrates. Frequency response characteristics of the HFET based amplifier and also of the complete MSM-HFET photoreceiverwere computer-simulated. One of the most important steps in device monolithic integration is isolation of the elements. In this project were considered two types of possible elements isolation: plasma etch (mesa) and implant isolation. A set of photolithography masks for chip fabrication on AlGaN/GaN layers was created. Anticipated fabrication of the designed MSM-HFET integrated photoreceiver in 1-um geometry should allow its RF operation.

13

Badanie wpływu technologii na parametry wybranych elementów optoelektronicznych

Zborowska-Lindert I., Boratyński B., Paszkiewicz B., Ohly T.

Elektronika : konstrukcje, technologie, zastosowania

|

2004

|

Vol. 45, nr 10

41-43

PL

Przedstawiono wyniki badań związanych z konstrukcją i wytwarzaniem fotodetektorów MSM oraz mikrobaterii fotowoltaicznych ze związków Ga(Al,In)As. W prawidłowej konstrukcji obydwu grup przyrządów, niezwykle istotna jest minimalizacja prądu ciemnego i upływności elementów. Opisano efekty pasywacji powierzchni fotodetektorów poprzez zastosowanie warstw dielektrycznych Si3NOx i AIN. Badano także wpływ konpozycji materiału warstwy aktywnej mikrobaterii fotowoltaicznej na jej prąd zwarciowy i napięcie rozwarcia.

EN

Influence of process technology on electrical parameters of Ga(Al,In)As MSM photodetectors and photovoltaic micro-arrays was envestigated. The effects of the dark current suppression due to surface passivation in MSM photodetectors with AIN and Si3NOx layers are presented. The photovoltaic arrays were fabricated as a series connection of seven Ga((Al,In)As PIN diodes. The influence of device active layer composition on the open circuit voltage and the short circuit current values was investigated.

14

Advanced technology of AIII-BV and AIII-N structures for microelectronics application

Boratyński B., Korbutowicz B., Paszkiewicz B., Paszkiewicz R., Pucicki D., Radziewicz D., Ściana B., Tłaczała M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2004

|

Vol. 52, nr 4

291-299

EN

In this work studies of MOVPE growth of InAlGaAs/ AlGaAs/GaAs heterostructures are presented. The HRXRD and SIMS measurements indicate the high structural and optical properties as well as high uniformity of thickness and composition of InAlGaAs quantum wells. This work is the first step towards elaboration of the technology of the strained InAlGaAs/GaAs heterostructures for advanced optoelectronic devices working in the visible part of the spectrum. The investigations of Si (n-type), Zn (p-type) b-doped GaAs epilayers and centre Si-b-doped InxGa1-xAs single quantum well (SQW) are presented. The b-doping layer was formed by SiH4 or DEZn introduction during the growth interruption. The electrical and optical properties of the obtained structures were examined using C-V measurement, EC-V electrochemical profiler, Raman spectroscopy (RS), photoreflectance (PR) and photocurrent (PC) spectroscopies. Technology of thick GaN layers grown on sapphire by HVPE is very promising as a part of freestanding GaN substrates manufacturing. Further works will be focused on the optimisation of growth, separating layers from substrates and surface polishing. The influence of the growth parameters on the properties of (Ga, Al)N/ Al2O3 and Mg dopant incorporation was studied.

15

Elektronika wysokotemperaturowa

Boratyński B., Strupiński W.

Elektronizacja : podzespoły i zastosowania elektroniki

|

2003

|

Vol. 23, nr 11

23-25

16

Transistors today - after 50 years in microelectronics

Boratyński B.

Optica Applicata

|

2002

|

Vol. 32, nr 3

437-447

EN

The current status and future trends in bipolar junction transistors (BJT) and field effect transistors (FET) construction design, technology and applications are presented. The development of heterojunction bipolar transistor (HBT) and high electron mobility transistor (HEMT) devices which find a widespread use in communication and optoelectronic circuits has been closely tied with advances in epitaxial growth of semiconductor nanolayers and the so-called bandgap engineering. Application of new semiconductor materials such as SiGe, AlInAs, GaN, AlGaN in traditional devices allows improving substantially their parameters. The comparison of the performance of advanced devices is given. Research results on advanced GaN HFET (heterostructure field effect transistor) devices fabricated in our semiconductor device laboratory are presented. Future trends in the device design market are signalised

17

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

|

2000

|

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.