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1

Struktury detektora podczerwieni na bazie supersieci II rodzaju ze związków InAs/GaSb

Kaniewski J., Jasik A., Regiński K., Sankowska I., Pierścińska D., Pierściński K., Papis E., Wawro A.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 10

18-21

PL

W artykule przedstawiono aktualny stan technologii detektorów podczerwieni na bazie supersieci II-rodzaju ze związków InAs/GaSb. Detektory te wytwarzane są metodą epiaksji z wiązek molekularnych MBE w Instytucie Technologoii Elektronowej (ITE) w Warszawie.

EN

Present state of technology of infrared detectors based on InAs/GaSb type-II superlattice is presented. Detectors of this type are fabricated by molecular beam epitaxy MBE at the Institute of Electron Technology (IET) in Warsaw.

2

Low resistance ohmic contacts to n-GaAs for application in GaAs/AlGaAs quantum cascade lasers

Karbownik P., Barańska A., Szerling A., Macherzyński W., Papis E., Kosiel K., Bugajski M., Tłaczała M., Jankieła R.

Optica Applicata

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2009

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Vol. 39, nr 4

655-661

EN

This paper reports on the results of optimization of ohmic contacts for GaAs/AlGaAs quantum cascade lasers (QCLs). Technological parameters during optimization concerned surface preparation, evaporation method, and thermal treatment. The aim of this research was to obtain low resistance and time stable ohmic contacts. The average specific contact resistance was 6×10-7 ?cm-2 with record value below 3×10-7 ?cm-2. It appears that the crucial role in contact formation is played by the in-situ surface pretreatment and thermal processing. Circular transmission line method (CTLM) was applied for electrical characterization of Ni/AuGe/Ni/Au metallization system. Secondary ion mass spectroscopy (SIMS) was used for determination of Au diffusion into semiconductor. The system presented was used in fabrication of pulse operating QCLs. The lasers mounted with diamond heat spreaders on copper block cooled by liquid nitrogen (LN) achieved optical powers over 1 W, threshold current density values of 7 kAcm-2 and differential efficiencies above 1 W/A.

3

(100) GaAs surface treatment prior to contact metal deposition in AlGaAs/GaAs quantum cascade laser processing

Papis E., Barańska A., Karbownik P., Szerling A., Wójcik-Jedlińska A., Bugajski M., Rzodkiewicz W., Szade J., Wawro A.

Optica Applicata

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2009

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Vol. 39, nr 4

787-797

EN

The effects of HCl-based chemical and Ar+ sputter etching treatment on (100) GaAs surface properties with the aim to develop the procedure of surface preparation before metal deposition have been investigated. Variable angle spectroscopic ellipsometry, X-ray photoelectron spectroscopy, atomic force microscopy and photoluminescence have been used to study the surface characterization. We show that combining chemical etching in 5% HCl with Ar+ sputter etching gives the best results for surface cleaning prior to metal deposition. The application of this two-step treatment allows to obtain Ni/AuGe/Ni/Au ohmic contact with rc = 2×10–6 .omega.cm2 with excellent adhesion and long-term thermal stability.

4

Application of SU8 Polymer in Waveguide Interferometer Ammonia Sensor

Bednorz M., Urbańczyk M., Pustelny T., Piotrowska A., Papis E., Sidor Z., Kamińska E.

Molecular and Quantum Acoustics

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2006

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Vol. 27

31-40

EN

The deposition possibility of the polymer based waveguides in low cost and relatively simple and repeatable process is presented in experimental results. The waveguide can be easily formed into Mach-Zehnder interferometer by photolithography. The numerical analysis using the beam propagation method yields very promising results of sensor interaction with ammonia. The aim of future work will be to deposit the desired interferometer and compare the efficiency of the sensor with computer analysis.

5

Design and fabrication of GaSb/InGaAsSb/AlGaSb mid-infrared photodetectors

Piotrowski T. T., Piotrowska A., Kamińska E., Piskorski M., Papis E., Gołaszewska K., Kątcki J., Ratajczak J., Adamczewska J., Wawro A., Piotrowski J., Orman Z., Pawluczyk J., Nowak Z.

Opto-Electronics Review

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2001

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Vol. 9, No. 2

188-194

EN

The paper reports on the design and fabrication of LPE-grown GaSb/n-InxGa₁-xAsySb₁-y/p-AlxGa₁-xAsySb₁-y heterojuction photodetectors operating in the 2-2.4 mm wavelength region. Experiments on LPE growth of high-x-content quaternaries as well as optimisation of device processing has been carried out. LPE growth at T » 530°C enabled obtaining lattice matched heterostructures with 19% indium in the active layer In₀.₁₉Ga₀.₈₁As₀.₁₆Sb₀.₈₄/Al₀.₂₄Ga₀.₇₆As₀.₀₄Sb₀.₉₆ and photodetectors with lc = 2.25 um. By increasing the temperature of epitaxial growth to 590°C In₀.₂₃Ga₀.₇₇As₀.₁₈Sb₀.₈₂/Al₀.₃₀Ga₀.₇₀As₀.₀₃Sb₀.₉₇ heterostructures (with 23% indium content) suitable for photodetectors with lc = 2.35 um have been obtained. Mesa-type photodiodes were fabricated by RIE in CCl₄/H₂ plasma and passivated electrochemically in (NH₄)₂S. These devices are characterised by differential resistance area product up to 400 Wcm² and the detectivity in the range the range 3´1010-2´1011 cmHz¹/²/W, in dependence on the photodiode active area and cut-off wavelength.

6

Wzrost epitaksjalny i właściwości warstw poczwórnych na bazie GaSb

Piskorski M., Papis E., Gołaszewska K., Piotrowski T. T., Piotrowska A., Barcz A., Zieliński M., Adamczewska J., Sawicki M.

Elektronika : konstrukcje, technologie, zastosowania

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2001

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Vol. 42, nr 8-9

29-31

EN

Quaternary compounds grown on GaSb substrates are very attractive materials for IR applications. Ga1-xJnxASySb1-y are used as active layers in emitters and detectors, for mid infrared region, whereas Ga1-xAlxASySb1-y compounds are usefull materials for low refractive index cladding layers in DH lasers and for wide gap window layer in photodetectors operating at wavelengths up to 2,4 um. Among various techniques of growing epitaxial layers of III—V semiconductors, liquid phase epitaxy (LPE) still remains interesting method due to its simplicity and satisfactory results.

7

Obróbka powierzchni (100) GaSb w związkach zawierających siarkę

Papis E., Piotrowska A., Piotrowski T. T., Kamińska E., Gołaszewska K., Kudła A., Pankowski P., Szade J., Winiarski A.

Elektronika : konstrukcje, technologie, zastosowania

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2001

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Vol. 42, nr 8-9

41-44

EN

The influence of sulfide treatments of the (100) GaSb surface have been investigated. Sulfide passivating layers have been prepared by chemical and electrochemical process using 1M Na2S, 21% (NH4)2S, 0,3 M (NH2)2CS aqueous and alcohol solutions. Spectroscopic elipsometry (ES), x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) were used to characterize of the superficial sulfide layers. Our results show that sulfide pretreatment in 1M Na2S in isopropanol and annealing under flowing H2 (T= 640°C, t = 1 h) is the best technique of surface preparation of GaSb substrate prior to epitaxy (the thickness of superficial oxide layer is about d = 0,8 nm with minimal surface roughness d= 0,23 nm.

8

Technology and properties of GaInAsSb layers grown on GaSb substrates

Piskorski M., Papis E., Gołaszewska K., Jung W., Adamczewska J., Perchuć L.

Electron Technology

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2000

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Vol. 33, No. 3

393-399

EN

The Ga1-xInxAsySb1-y layers were grown on GaSb substrates by the liquid phase epitaxy (LPE) technique. The materials were characterized by means of optical microscopy, X--ray high resolution diffractometry, electroprobe microanalysis (EPXMA) and numerical analysis of measured C-V characteristic of Schottky barrier junction Hg--GaInAsSb. The different compositions of Ga1-xInxAsySb1-y compounds lattice matched to GaSb substrates with x value changing from 0.021 to 0.23, were established. Applying of sulfidation technique to the substrate's surface before growth, improved layer's quality n-type layers, with carrier concentration below 3⋅10⁻¹⁵ cm⁻³ have been grown.

9

Wet and dry etching of GaSb/GaInAsSb photodiode heterostructures

Piotrowski T. T., Papis E., Guziewicz M., Gołaszewska K., Kamińska E., Piotrowska A., Andreev I. A., Mikhailova M. P., Kunitsyna E. V., Yakovlev Y. P.

Electron Technology

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1998

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Vol. 31, No. 3/4

304-310

EN

Antimonide-based heterostrucures lattice matched to GaSb substrates are particulary attractive for high-efficiency fast photodiodes (PDs) working in the mid-infraret region of the spectrum. Much of the recent progress in the technology of these devices has occurred on the materials side. In order to exploit this potential considerable advances in processing technology, including controlled mesa etching and photodiode surface passivation techniques are required. This paper deals the processes of wet and dry etching of GaSb-based compounds in order to form and passivate GaSb/Ga₀.₇₈In₀.₂₂As₀.₁₈Sb₀.₈/Ga₀.₆₆Al₀.₃₄As0.₂₅Sb₀.₉₇₅ PD mesa sructures. HCL + H₂O₂ + H₂O solutions and CCL₄/H₂ plasmas have been used for masa etching and thier results on mesa profile and etch depth control have been compared. For mesa passivation a surface treatment in (NH₄)₂S water solution was carried out. Examination of PD performance through the measurments of current-voltage and spectral responsivity characteristic have shown that unpassivated photodode structures are characterized by darc current Id=5 ÷ 10 µA at reverse bias UR = -1 V, and quantum efficiency ƞ = 0.5 ÷ 0.7 at ʎ = 2.3 µm and T = 300 K. reduction of dark curent to Id ≤ 3 µA has been obtained for GaSb/GaAlAsSb mesa structures processed in (NH₄)₂S.