scispace - formally typeset
Search or ask a question

Showing papers on "Antimonide published in 1998"


Journal ArticleDOI
TL;DR: In this article, the InAs/GaSb/AlAsSb quantum wells were modeled in detail and the large conduction-band offset of the AlAs-Sb barriers with respect to the INAs wells allowed the lasing wavelength to be shortened to at least 1.9 μm.
Abstract: Optically and electrically pumped infrared lasers based on intersubband transitions in InAs/GaSb/AlAsSb quantum wells are modeled in detail. The large conduction-band offset of the AlAsSb barriers with respect to the InAs wells allows the lasing wavelength to be shortened to at least 1.9 μm. Furthermore, the small InAs electron mass results in longer phonon-limited lifetimes in the upper lasing subband as well as larger dipole matrix elements. This leads to the prediction of lower threshold currents, and hence, higher cw operating temperatures than for quantum cascade lasers based on the InGaAs/InAlAs/InP system.

60 citations


Journal ArticleDOI
TL;DR: In this article, the authors used epitaxial ternary and quaternary layers grown on GaSb substrates for thermophotovoltaic (TPV) devices.

42 citations


Journal ArticleDOI
J. Harper, M. Weimer, D. Zhang, C.-H. Lin, S. S. Pei 
TL;DR: In this article, cross-sectional scanning tunneling microscopy (STM) was used to examine two important aspects of material and interface quality in the mixed-anion InAs/GaSb/AlSb system under growth conditions similar to those presently employed for type-II quantum well and interband cascade lasers.
Abstract: We have used cross-sectional scanning tunneling microscopy (STM) to examine two important aspects of material and interface quality in the mixed-anion InAs/GaSb/AlSb system under growth conditions similar to those presently employed for type-II quantum well and interband cascade lasers: (1) anion cross incorporation in the bulk (specifically, unintended substitution of As for Sb within the GaSb layers); and (2) the roughness spectrum at the common-anion AlSb-on-GaSb heterojunction. Two apparently different anion defects are noted in the GaSb layers, but the demonstration of a linear correlation between the bulk defect density observed with STM and the arsenic valve setting during antimonide layer growth clearly establishes background arsenic incorporation as the common origin for both of these defects. The roughness spectrum at the AlSb-on-GaSb interface displays a surprisingly short correlation length that is dominated by heterogeneity in the cation rather than anion sublattice. The relationship of these...

32 citations


Patent
17 Nov 1998
TL;DR: An antimony/Lewis base adduct of the formula SbR3.L is proposed in this paper, where each R is independently selected from C1 - C8 alkyl, C1- C8 perfluoroalkyl, C 1 - C 8 haloalkyl and halo; and L is a Lewis base ligand coordinating with Sbr3.
Abstract: An antimony/Lewis base adduct of the formula SbR3.L, wherein each R is independently selected from C1 - C8 alkyl, C1 - C8 perfluoroalkyl, C1 - C8 haloalkyl, C6 - C10 aryl, C6 - C10 perfluoroaryl, C6 - C10 haloaryl, C6 - C10 cycloalkyl, substituted C6 - C10 aryl and halo; and L is a Lewis base ligand coordinating with SbR3. The adducts of the invention are useful as metal source compositions for chemical vapour deposition, assisted chemical vapor deposition (e.g., laser-assisted chemical vapor deposition, light-assisted chemical vapor deposition, plasma-assisted chemical vapor deposition and ion-assisted chemical vapor deposition), ion implantation, molecular beam epitaxy, and rapid thermal processing, to form antimony or antimony-containing films.

24 citations


Journal ArticleDOI
TL;DR: The metal-rich antimonide Zr2V6Sb9 has been prepared by arcmelting of stoichiometric mixtures of Zr, V, and VSb2 as mentioned in this paper.
Abstract: The metal-rich antimonide Zr2V6Sb9 has been prepared by arc-melting of stoichiometric mixtures of Zr, V, and VSb2. Zr2V6Sb9 is the first example of a ternary ordered (filled) variant of the unusual V15Sb18 structure type. In addition to strong metal–antimony bonding, the crystal structure is significantly stabilized by bonding V–V and Sb–Sb interactions, whereas the Zr atoms do not form short metal–metal bonds. Band structure calculations using the Extended Huckel approximation reveal Zr2V6Sb9 being metallic, in agreement with the Pauli paramagnetism experimentally observed.

20 citations


Journal ArticleDOI
01 Oct 1998
TL;DR: In this article, an electron channel with high Hall mobility was observed at the interface of isotype p-GaInAsSb/p-InAs heterojunctions with undoped and slightly doped quaternary layers at low temperatures.
Abstract: Type II antimonide–arsenide based heterostructures have recently received great attention from researchers engaged in the design of mid-infrared optoelectronic devices. Magnetotransport properties of the semimetal channel and the interface electroluminescence were experimentally studied on type II broken-gap GaInAsSb/InAs single heterojunctions grown by LPE with high quality interface. An electron channel with high Hall mobility was, for the first time, observed at the interface of isotype p-GaInAsSb/p-InAs heterojunctions with undoped and slightly doped quaternary layers at low temperatures. A depletion of the electron channel was found to be due to the heavy acceptor doping level of the quaternary layer. The two-dimensional nature of the interface carriers was established by Shubnikov–de Haas oscillation experiments at 1.8–4.2 K under magnetic fields up to 9–14 T. Intensive interface electroluminescence in the structures under study was observed in the spectral range of 3–4 µm at low temperatures (4.2–77 K). A model of the recombination transition at the type II broken-gap interface was proposed and experimentally confirmed. A new physical approach to the design of mid-infrared tunnelling-injection lasers is demonstrated.

14 citations


Journal ArticleDOI
TL;DR: In this article, a Si-doped InAs/AlSb short-period superlattice was used to modulate the current-carrying InAs channel of an InAs and AlSb heterostructure field effect transistor (HFET).
Abstract: Modulation doping of InAs/AlSb quantum wells generally requires the use of chalcogenide donor impurities because silicon, the usual donor of choice in molecular beam epitaxy, displays an amphoteric behavior in antimonide compounds. In the present article, we demonstrate the use of a Si-doped InAs/AlSb short-period superlattice (with Si co-deposited with the InAs) to modulation dope the current-carrying InAs channel of an InAs/AlSb heterostructure field-effect transistor (HFET). Using this new approach, we have fabricated 1.5 μm gate InAs/AlSb HFETs with a measured extrinsic transconductance of 550 mS/mm at 300 K. The present band gap engineering approach eliminates the requirement for captive chalcogenide donor sources to modulation dope InAs/AlSb quantum wells. Design alternatives to the use of the short-period superlattice are also considered and demonstrated.

12 citations


Journal ArticleDOI
TL;DR: A detailed study of the growth of Al1−xInxAs1−ySby epilayers has been conducted in this article, where the compositional dependence on the Sb:As flux, Sb :In flux, and substrate temperature has been studied.
Abstract: Al1−xInxAs1−ySby epilayers and Al1−xInxAs1−ySby/GaSb multilayers (0.5⩽y⩽1.0) have been grown by molecular beam epitaxy on GaSb (100) substrates as part of an investigation for potential use of this material’s system as kinetic heterojunctions (KHJs). Viable KHJ’s require lattice matching and a zero-conduction-band offset to GaSb, necessitating a high degree of compositional control. Therefore, a detailed study of the growth of Al1−xInxAs1−ySby epilayers has been conducted. Synthesis of the arsenide/antimonide quaternary system is problematic due to the miscibility gap throughout the composition range, therefore, the compositional dependence on the Sb:As flux, Sb:In flux, and substrate temperature has been studied. In situ reflection high-energy electron diffraction was used to monitor the surface reconstruction during growth. Crystalline quality and composition of single layer and multilayer samples have been determined by double-crystal x-ray diffraction and electron dispersion spectroscopy. Hall-effect ...

11 citations



Journal ArticleDOI
TL;DR: In this paper, a technique for protecting alkali-antimonide visible light photocathodes against deterioration by exposure to impurities, during handling or storage in poor vacuum or gas, was described.
Abstract: We describe a technique for protecting alkali-antimonide visible light photocathodes against deterioration by exposure to impurities, during handling or storage in poor vacuum or gas. The photocathodes are coated with a ∼1 μ m vacuum-deposited hexatriacontane film, which can be subsequently removed by low-temperature sublimation . We show that Cs 3 Sb coated photocathodes can be exposed for several minutes to considerable amounts of oxygen, without deterioration. Their initial photoemission properties are almost fully recovered after film removal.

10 citations


Proceedings ArticleDOI
TL;DR: In this paper, the authors reported a room-temperature threshold current density as low as 173 A/cm 2 for a 2-micrometer GaInAsSb quantum well laser and 225 A/ cm 2 for the 4-QW laser.
Abstract: Compressively strained 2 micrometer GaInAsSb quantum well lasers with large valence band offsets and broadened waveguides display a record characteristic temperature, T 0 equals 140 degrees Kelvin for a 4-QW laser and a differential efficiency of 0.74 for a pulsed 2-QW device. The T 0 of these antimonide lasers is 65% more than that reported for phosphide-based lasers operating at 2 micrometer wavelength. A room-temperature threshold current density as low as 173 A/cm 2 has been observed for a 2-QW device and 225 A/cm 2 for the 4-QW laser.

Patent
15 Sep 1998
TL;DR: In this paper, the authors proposed a component comprising a heterojunction formed between a first binary III-V semiconductor material substrate, in particular of Ga As, and at least a thin epitaxial layer of a second ternary antimonide-arsenide 3-V alloy.
Abstract: The invention concerns a component comprising a heterojunction formed between a first binary III-V semiconductor material substrate, in particular of Ga As, and at least a thin epitaxial layer of a second ternary III-V semiconductor material at least lattice-mismatched with the material the former, with at least a buffer inter-layer of a third III-V semiconductor material lattice-matched between the substrate layer and the thin layer. The buffer layer has a metamorphic structure and the thin epitaxial layer is essentially devoid of cross-hatch pattern and has a surface roughness less than 2 nm. The buffer layer material is particular a binary, ternary or quaternary antimonide III-V alloy, or at least a ternary antimonide-arsenide III-V alloy: the component can in particular comprise a GaAs/AlxIn1-xAs/InyGa1-yAs heterostructure with a fraction of indium molar y > 25 %.

Journal ArticleDOI
TL;DR: In this article, ballistic electron emission microscopy (BEEM) was employed to directly probe AlSb barriers as well as more complicated structures such as selectively doped n-type InAs/AlSb superlattices.
Abstract: Due to its large band gap, AlSb is often used as a barrier in antimonide heterostructure devices. However, its transport characteristics are not totally clear. We have employed ballistic electron emission microscopy (BEEM) to directly probe AlSb barriers as well as more complicated structures such as selectively doped n-type InAs/AlSb superlattices. The aforementioned structures were grown by molecular beam epitaxy on GaSb substrates. A 100 A InAs or 50 A GaSb capping layer was used to prevent surface oxidation from ex situ processing. Different substrate and capping layer combinations were explored to suppress background current and maximize transport of BEEM current. The samples were finished with a sputter deposited 100 A metal layer so that the final BEEM structure was of the form of a metal/capping layer/semiconductor. Of note is that we have found that hole current contributed significantly to BEEM noise due to type II band alignment in the antimonide system. BEEM data revealed that the electron barrier height of Al/AlSb centered around 1.17 eV, which was attributed to transport through the conduction band minimum near the AlSb X point. Variation in the BEEM threshold indicated unevenness at the Al/AlSb interface. The metal on semiconductor barrier height was too low for the superlattice to allow consistent probing by BEEM spectroscopy. However, the superlattice BEEM signal was elevated above the background noise after repeated stressing of the metal surface. A BEEM threshold of 0.8 eV was observed for the Au/24 A period superlattice system after the stress treatment.

Patent
28 Apr 1998
TL;DR: In this paper, a thin-film-coated photocathode consisting of first material consisting of potassium cesiuin antimonide (CesIin) and a thinfilm coating of a second material, cesium bromide (CsBr), was described.
Abstract: This invention discloses a thin-film-coated photocathode, including a photocathode formed of first material consisting of potassium cesiuin antimonide and a thin-film coating of a second material consisting of cesium bromide (CsBr).

Proceedings ArticleDOI
03 Dec 1998
TL;DR: In this article, an optically-pumped all-epitaxial 1.56 /spl mu/m VCSEL on an InP substrate was presented, which combined a simple InGaAs active region with AlAsSb-AlGaAsSsb mirror stacks.
Abstract: We demonstrate an optically-pumped all-epitaxial 1.56 /spl mu/m VCSEL on an InP substrate which combined a simple InGaAs active region with AlAsSb-AlGaAsSb mirror stacks. The AlGaAsSb material system is well-suited for fabrication of high-reflectivity DBRs due to a significantly higher refractive index contrast than achievable using InAlGaAsP, particularly at 1.55 /spl mu/m.

Journal ArticleDOI
TL;DR: In this article, the authors describe an elongated ccp arrangement of As or Sb atoms along the tetrahedral holes, where half of the holes are centered by Ca atoms.
Abstract: Source of material: The title compounds were synthesized from stoichiometric amounts of the elements (Rb:Ca:As(Sb) =1:1:1) in sealed niobium ampoules in evacuated quartz tubes at 973 K. RbCaAs and RbCaSb are isostructural with KMnAs (see ref. 1). The structure can be described as an elongated ccp arrangement of As or Sb atoms along [101]. Half of the tetrahedral holes are centered by Ca atoms. The filled tetrahedra share edges forming ^[CaX4/4] layers (X = As, Sb) parallel ((Ю1) with J(Ca-As) = 296.4 pm and ¿(Ca-Sb) = 315.8 pm. These layers are held together by the Rb atoms, which are displaced from the centers of the octahedra resulting in a pyramidal coordination (CN = 5). The band gaps from diffuse reflexion spectra Eg = 2.4 eV (RbCaAs) and Eg = 2.3 eV (RbCaSb) are in agreement with the ruby-red color of these compounds.

Patent
18 Mar 1998
TL;DR: In this article, the preparation processes include mixing alpha-hydroxy-carboxylic acid and amide in the hydroxyl-to-amino molar ratio of 0.5-3.0, heating while stirring to 40-150 deg. c for 1-5 hr.
Abstract: The preparation processes include mixing alpha-hydroxy-carboxylic acid and amide in the hydroxyl-to-amino molar ratio of 0.5-3.0, heating while stirring to 40-150 deg.c, adding antimony oxide in the hydroxyl-to-antimony molar ratio of 0.5-4.0 and reaction at 100-150 deg. c for 1-5 hr. By using low-volatility no-irritant smell reaction material, the present invention has improved production and use environment and the passivating agent product has excellent performance.

Patent
28 Apr 1998
TL;DR: In this paper, a thin-film-coated photocathode consisting of first material consisting of potassium cesium antimonide (CAnt), and then a thin film coating of a second material, consisting of Cesium bromide (CsBr).
Abstract: This invention discloses a thin-film-coated photocathode, including a photocathode formed of first material consisting of potassium cesium antimonide and a thin-film coating of a second material consisting of cesium bromide (CsBr).

Book ChapterDOI
01 Jan 1998
TL;DR: In this paper, the optical properties of aluminum antimonide (AlSb) have been analyzed for a limited number of samples and the refractive index, n, and extinction coefficient, k, of AlSb have been measured.
Abstract: Publisher Summary This chapter analyzes the optical properties of aluminum antimonide (AlSb). The refractive index, n, and the extinction coefficient, k, of AlSb have been measured for a limited number of samples. The two main reasons for this are that large high-quality single crystals are difficult to grow and the surface of AlSb reacts rapidly with the atmosphere to produce a relatively thick contaminated layer. One method for measuring the optical properties of semiconductors—especially for the ultraviolet (UV) and visible regions—is spectroscopic ellipsometry. However, contamination-free surfaces are needed for precise ellipsometric measurements. The chapter reviews the measurements of the dependence of energy-gap absorptance of AlSb at room temperature for hydrostatic pressures from atmospheric up to the phase change at about 8 GPa; the reflectance of room-temperature AlSb between 16 m and 40 m, which includes the infrared lattice reflectance band; and the fundamental reflection band of six III–V compound semiconductors at liquid helium-temperature.

01 Jan 1998
TL;DR: In this article, an antimonide based interdiffused quantum well structure is carefully examined including experimental results, with strong emphasis on its tunable properties and summerized with focus on its device applications and future development.
Abstract: Antimonide(Sb) is said to be an emerging optoelectronic material for both high speed and long wavelength electronics devices. Recently, there has been much research activities on antimonide based system. Among Group V elements, antimonide is of particular interest as its lattice parameter matches solid solutions of various ternary and quarternary III - V compounds whose band gap cover a wide spectral range from absorption in antimonide based superlattices, detection of longer wavelength of 8 to 14μm is possible. With the technique of interdiffusion applying to an antimonide based quantum well, we will be able to obtain devices which are bias tunable. This technique of interdiffusion is a thermal process which induces an interdiffusion of the constituent atoms across the heterointerfaces of an as-grown quantum well, and results in modification of the composition and confinement profiles of the quantum well structures. Hence, the optical properties of the material can be modified to desire values. In this presentation, an antimonide based interdiffused quantum well structure is carefully examined including experimental results, with strong emphasis on its tunable properties and summerized with focus on its device applications and future development.

Journal ArticleDOI
TL;DR: The metal-rich antimonide Zr2V6Sb9 has been prepared by arcmelting of stoichiometric mixtures of Zr, V, and VSb2 as discussed by the authors.
Abstract: The metal-rich antimonide Zr2V6Sb9 has been prepared by arc-melting of stoichiometric mixtures of Zr, V, and VSb2. Zr2V6Sb9 is the first example of a ternary ordered (filled) variant of the unusual V15Sb18 structure type. In addition to strong metal–antimony bonding, the crystal structure is significantly stabilized by bonding V–V and Sb–Sb interactions, whereas the Zr atoms do not form short metal–metal bonds. Band structure calculations using the Extended Huckel approximation reveal Zr2V6Sb9 being metallic, in agreement with the Pauli paramagnetism experimentally observed.

Book ChapterDOI
01 Jan 1998
TL;DR: In this paper, the qualities of GaSb substrates commonly used for the preparation of III-V antimonide epilayers were studied before and after growing GaInAsSb multi-layers by MOCVD using PL, FTIR and DCXD together with the electrical properties and EPD value.
Abstract: The qualities of GaSb substrates commonly used for the preparation of III-V antimonide epilayers were studied before and after growing GaInAsSb multi-layers by MOCVD using PL, FTIR and DCXD together with the electrical properties and EPD value. The correlation between the substrate qualities and epilayer properties was briefly discussed. The good property epilayers of GaInAsSb and, then, the high preformance of 2.3 um photodetectors were achieved only using the good quality GaSb wafers as the substrates.

Journal ArticleDOI
TL;DR: Manganese cation binding energy, dispersion curves, total phonon spectrum, and temperature dependence of the lattice and magnetic contributions to specific heat of Mn2Sb have been calculated in this paper.
Abstract: Manganese cation binding energy, dispersion curves, total phonon spectrum, and temperature dependence of the lattice and magnetic contributions to specific heat of Mn2Sb have been calculated.

Journal ArticleDOI
TL;DR: In this paper, a self-consistent numerical calculation of the electronic structure of field effect transistors where the electric transport channel is a quasi-two-dimensional plan of antimonide doping in a silicon crystal is presented.

Proceedings ArticleDOI
01 Jan 1998
TL;DR: In this paper, the subband of Al/sub x/In/sub 1-x/Sb/InSb quantum-well structure under the effect of interdiffusion were calculated.
Abstract: The subband of Al/sub x/In/sub 1-x/Sb/InSb quantum-well structure under the effect of interdiffusion were calculated. The model use the 14-band calculation and the effective Hamiltonian approach. The results show that the interband transition energy is relatively small, compared to quantum well constructed by As based. With a particular Al concentration and design, the interband transition energy at around 200-300 meV. This is the range for medium wavelength infrared region. Hence, we suggest in this paper to use Al/sub x/In/sub 1-x/Sb/InSb quantum-well structure for infrared detectors. The effect of interdiffusion shows a shift in interband transitions energy, which is useful for find tunneling the transition energy. When it apply to infrared detector, the absorption wavelength can be tune by interdiffusion to a desire value. In this paper, we propose to use antimonide based interdiffusion quantum well as an infrared detector, and show it wavelength tunability.

Proceedings ArticleDOI
22 Jun 1998
TL;DR: In this paper, an antimonide based interdiffused quantum well structure is carefully examined including experimental results, with strong emphasis on its tunable properties and summarized with focus on its device applications and future development.
Abstract: Antimonide (Sb) is said to be an emerging optoelectronic materials for both high speed and long wavelength electronics devices. Recently, there has been much research activities on antimonide based system. Among Group V elements, antimonide is of particular interest as its lattice parameter matches solid solutions of various ternary and quaternary III-V compounds whose band gap cover a wide spectral range from absorption in antimonide based superlattices, detection of longer wavelength of 8 to 14 micrometers is possible. With the technique of interdiffusion applying to an antimonide based quantum well, we will be able to obtain devices which are bias tunable. This technique of interdiffusion is a thermal process which induces an interdiffusion of the constituent atoms across the heterointerfaces of an as-grown quantum well, and results in modification of the composition and confinement profiles of the quantum well structures. Hence, the optical properties of the material can be modified to desire values. In this presentation, an antimonide based interdiffused quantum well structure is carefully examined including experimental results, with strong emphasis on its tunable properties and summarized with focus on its device applications and future development.