Showing papers on "Epitaxy published in 1972"
TL;DR: In this paper, the authors report the first time switching and modulation of light in a magneto-optic waveguide that is a single-crystal epitaxially grown iron-garnet film.
Abstract: We report for the first time switching and modulation of light in a magneto‐optic waveguide that is a single‐crystal epitaxially grown iron‐garnet film. These experiments involve the Faraday rotation of the magnetic film and the motion of magnetization in the plane of the film. We have modulated light from a 1.152‐μm laser up to 80 MHz. We were also able to switch light between two waveguide modes by applying a magnetic field as small as 0.2 Oe.
170 citations
TL;DR: Pd2Si contacts to single crystal silicon have been made by depositing Pd at room temperature and annealing at a succession of elevated temperatures as discussed by the authors, which leads to an appreciation of the excellent electrical characteristics of these contacts which are shown to be superior to alloyed aluminum.
Abstract: Pd2Si contacts to single crystal silicon have been made by depositing Pd at room temperature and annealing at a succession of elevated temperatures. The silicide initially formed is a single crystal, even at room temperature. Its crystal structure is uniquely related to that of the underlying silicon with the basal plane of Pd2Si making an excellent match, with respect to silicon atom positions, with the (111) plane of silicon. Understanding this epitaxy leads to an appreciation of the excellent electrical characteristics of these contacts which are shown to be superior to alloyed aluminum. For comparison, barrier height measurements reproduce earlier results of Kircher on Pd2Si formed during a high temperature (200°C) deposition of Pd.
100 citations
TL;DR: The epitaxial growth of GaN by vapor phase reaction between GaCl and NH 3 in a He carrier gas was described in this paper, where single crystal layers 100-200 ωm thick and ∼ 1 cm 2 in area were obtained on (0001) oriented sapphire substrates at deposition temperatures near 1050 °C.
87 citations
75 citations
TL;DR: In this paper, the steady-state surface photovoltage (SPV) method of measuring minority carrier diffusion length (L ) has been extended to the case of an epitaxial layer on a thick substrate.
Abstract: Analysis of the steady-state surface photovoltage (SPV) method of measuring minority carrier diffusion length ( L ) has been extended to the case of an epitaxial layer on a thick substrate. In layers with thickness greater than four diffusion lengths, the measurement yields the bulk value of L . For layers thinner than 0.5 L , the measured value is that of the substrate. For intermediate thicknesses, the bulk value of L can be estimated. The method also provides a sensitive means of observing the influence of surface conditions on the absorption characteristics of silicon.
74 citations
TL;DR: In this paper, the exciton gap in indium phosphide and gallium arsenide was estimated to be approximately 10-3 in certain regions of typical epitaxial layers.
Abstract: Photoluminescence spectra of refined epitaxial indium phosphide and gallium arsenide show clearly a close correspondence of bound exciton transitions. Classified in both materials are emissions due to excitons bound to neutral acceptors and donors, free exciton peaks and various types of phonon coupling. Excitons bound to neutral acceptors in both materials give rise to a sharp doublet emission which readily reveals the presence of strain in the sample. The magnitude of the strain is estimated to be approximately 10-3 in certain regions of typical epitaxial layers. Reflectivity experiments provide new estimates of the exciton gaps-1.4182 eV in indium phosphide and 1.5150 eV in gallium arsenide.
74 citations
TL;DR: In this article, single crystal epitaxial layers of Gaxln1−xP alloys have been grown by the steady-state liquid phase (LPS) epitaxia growth technique on (111)B GaAs substrates.
Abstract: Single crystal epitaxial layers of Gaxln1−xP alloys have been grown by the steady-state liquid phase epitaxial growth technique on (111)B GaAs substrates. The crystal growth process has been studied in detail and the resultant epitaxial layers have been characterized with respect to their structural, electrical and optical properties. Epitaxial layers of good structural quality could be grown only in the composition range x = 0.48 to 0.53, where the lattice parameter is close to that of the GaAs substrate. The band gap of these crystals was in the range 1.86 – 1.92 eV as determined by optical absorption and photoluminescence measurements.
72 citations
TL;DR: In this article, a multiple layer liquid phase epitaxial technique is described, where thin solutions are used to achieve epitaxials in the thickness range of one micrometer which are uniform over relatively large areas.
66 citations
TL;DR: In this paper, liquid phase epitaxy (LPE) by dipping substrates into supercooled fluxed solution provides a convenient way of changing the melt and film composition by substitutions such as gadolinium, samarium or lanthanum for yttrium.
65 citations
TL;DR: In this article, single crystals of boron arsenide, identified by the x-ray diffraction method, have been prepared by the chemical transport of polycrystalline BORON arsenide in the presence of a temperature gradient.
Abstract: Boron arsenide, a semiconductor with an energy gap of 1.46 eV, decomposes irreversibly at temperatures above 900 °C, thus limiting the temperature of the crystal growth process. In this work, single crystals of boron arsenide, identified by the x‐ray diffraction method, have been prepared by the chemical transport of polycrystalline boron arsenide in the presence of a temperature gradient. The transported crystals are p type and have a resistivity of approximately 0.01 Ω cm in the temperature range 77–500 °K. The hole concentration and Hall mobility, essentially independent of temperature in the range 77–300 °K, have been estimated to be in the ranges of 1018–1019 cm−3 and 100–400 cm2V−1sec−1, respectively. In spite of the high carrier concentrations, the transported crystals are suitable as substrates for the epitaxial growth of boron arsenide with controlled dopant distribution.
61 citations
Patent•
01 Mar 1972TL;DR: An apparatus for the liquid-phase epitaxial growth of multilayer wafer comprising a refractory furnace tube, a boat placed in the furnace tube and having a plurality of bathes which are aligned in the longitudinal direction of the furnace and respectively carry solutions each containing semiconductive substances, and a holding member for holding a substrate which is arranged to succeedingly flood the substrate with the solutions so as to epitaxially grow a multi-layer wafer on the substrate as mentioned in this paper.
Abstract: An apparatus for the liquid-phase epitaxial growth of multilayer wafer comprising a refractory furnace tube, a boat placed in the furnace tube and having a plurality of bathes which are aligned in the longitudinal direction of the furnace tube and respectively carry solutions each containing semiconductive substances, and a holding member for holding a substrate which is arranged to succeedingly flood the substrate with the solutions so as to epitaxially grow a multi-layer wafer on the substrate. The holding member arranged to upset the substrate upon pickingup or separating of the substrate from the solution so that the solution remained on the substrate is dropped from the substrate whereby unwanted mixing of the solutions neighbouring each other can be avoided.
TL;DR: In this paper, the properties of multilayer garnet films with stress and/or growth-induced uniaxial anisotropy are reported on a Gd 3 Ga 5 O 12 substrates.
Abstract: A conventional magnetic bubble material consists of a magnetic garnet film deposited on a nonmagnetic substrate. Garnet films with stress- and/or growth-induced uniaxial anisotropy are deposited by chemical vapor deposition (CVD) or liquid phase epitaxy (LPE) usually on Gd 3 Ga 5 O 12 substrates. In this B.S.T.J. Brief we report on the properties of multilayer garnet films deposited by LPE.
TL;DR: In this article, a 200MHz acoustic surface wave isolator was constructed employing an epitaxial layer of Ga-doped YIG on a gadolinium gallium garnet substrate.
Abstract: A 200‐MHz acoustic‐surface‐wave isolator has been constructed employing an epitaxial layer of Ga‐doped YIG on a gadolinium gallium garnet substrate.
TL;DR: In this article, the authors investigated the distribution of an amphoteric impurity silicon over the sublattices of GaAs in equilibrium with the gallium-rich solution, and the change in free energy is estimated for the transfer of silicon atoms from the arsenic sub-lattice to gallium sub-attice via the external liquid phase.
TL;DR: In this article, single-crystal layers of GaAs and GaP grown by chemical vapor deposition on sapphire and magnesium aluminate spinel substrates have been characterized by Lang x-ray topography and X-ray diffraction methods.
Abstract: Single‐crystal layers of GaAs and GaP grown by chemical vapor deposition on sapphire and magnesium aluminate spinel substrates have been characterized by Lang x‐ray topography and x‐ray diffraction methods. Separate topographs and diffraction peak profiles of the substrate and layer were obtained without removing the layer from the substrate. Epitaxial layers grown on substrates prepared by different growth techniques were examined and compared. Layers shown to be monocrystalline by back‐reflection Laue methods were revealed by Lang topography to be composed of small grains which were misoriented ±0.1° from the nominal orientation of the layer. Polishing scratches and growth striae in the substrates were found to influence the perfection of the layer. The Lang camera was used as a diffractometer to measure the misorientation of the layers from exact parallel epitaxy and to determine the radius of curvature of warped substrates.
TL;DR: In this paper, depth and temperature dependences of ion channeling were used to characterize 1−4μm Si layers on spinel substrates (Al2O3 · MgO).
Abstract: Depth and temperature dependences of ion channeling were used to characterize 1–4‐μm Si layers on spinel substrates (Al2O3 · MgO). Profiles of the density of crystal imperfections in the Si layers have been calculated from the channeling spectra. The imperfections are greatest near the interface, and the crystalline quality improves significantly with increasing distance from the interface. This technique is particularly applicable to heteroepitaxial layers containing high densities of crystal imperfections and can be used to monitor the relative influence of growth parameters on the crystalline quality of the layers.
TL;DR: Wang et al. as discussed by the authors showed that two-dimensional growth was very dominant in silicon epitaxial growth using hydrogen reduction of SiCl 4. This conclusion was also supported by other results concerning to surface morphology and growth with screw type stacking fault as nucleus center and so on.
Patent•
IBM1
TL;DR: In this paper, a planar dielectrically isolated semiconductor device is fabricated by depositing a surface layer of dielectric material on a major surface of a monocrystalline substrate, removing portions of the layer to define annular channels.
Abstract: A method of fabricating a planar dielectrically isolated semiconductor device by depositing a surface layer of dielectric material on a major surface of a monocrystalline substrate, removing portions of the layer to define annular channels, thermally oxidizing the exposed surface areas thereby forming annular ridges of SiO2, removing portions of the dielectric layer, selectively growing an epitaxial silicon layer over the surface wherein the surfaces of the annular ridges of SiO2 and the regions of epitaxial silicon are substantially co-planar. A semiconductor integrated circuit device having a silicon epitaxial layer on a monocrystalline substrate, a network of thermally oxidized silicon regions extending through the epitaxial layer, across the epitaxial layer-substrate interface and into the silicon substrate, the network separating the epitaxial silicon layer into individual pockets, a laterally extending region of low resistivity located generally at the epitaxial layer-substrate interface embodying a first conductivity type impurity, the first type impurity distribution in the epitaxial layer such that the concentration increases with depth.
TL;DR: In this paper, the thicknesses of the layers grown were measured as a function of the total amount the solution had cooled from a very carefully established equilibrium situation, and the results formed three series.
TL;DR: In this article, the equilibrium elastic strain in epitaxial islands of small size is shown to have a sawtooth dependence on island width by minimizing the systems energy as calculated from a periodic interaction potential between substrate and overgrowth.
TL;DR: In this paper, a model based on the formation of siliconoxygen pairs is proposed to explain a variety of anomalous phenomena associated with GaAs grown in the presence of silicon, SiO2, and/or oxygen.
Abstract: A model based on the formation of silicon‐oxygen pairs is proposed to explain a variety of anomalous phenomena associated with GaAs grown in the presence of silicon, SiO2, and/or oxygen. It is suggested that silicon atoms on gallium sites pair with interstitial oxygen atoms, forming a complex which behaves as an acceptor with energy levels near 0.2 and 0.4 eV below the conduction band. It is assumed that the complex can dissociate upon annealing below 850°C by the reaction 2(SiGaOi)−=(SiGaO2)0+SiGa++3e−. This reaction may be reversed at higher temperatures. The electrical and thermochemical properties of such a complex can explain annealing behavior, the occurence of a mobility maximum between 150 and 200°K, site distribution of silicon in p‐type silicon‐doped GaAs, change from n‐ to p‐type conductivity as a function of Si concentration in GaAs grown from Ga solutions, the formation of I (insulating) layers in GaAs grown by vapor‐phase epitaxy, and some of the anomalous behavior observed in GaAs devices. ...
TL;DR: In this article, the authors used a deep depletion MIS structure to obtain measurements of the carrier concentration and mobility variations through thin epitaxial films, (0·6-2 μm), of n-type silicon on sapphire substrates.
Abstract: A deep depletion MIS structure has been used to obtain measurements of the carrier concentration and mobility variations through thin epitaxial films, (0·6–2 μm), of n -type silicon on sapphire substrates. Both the mobility and the net donor concentrations decrease in the direction of the sapphire interface. The room temperature mobility in the material close to the sapphire interface is shown to be limited by scattering at charged defects but in accumulation layers adjacent to the oxide interface a phonon scattering limitation is observed and a large proportion of the oxide interface scattering is shown to be specular. Under certain conditions shallow donor states can be generated at the sapphire interface in densities of the order of 10 12 cm −2 . A new technique for measuring the energy distribution of fast interface states at the oxide interface in a film with nonuniform doping is described. The energy distributions obtained on the silicon-on-sapphire films investigated in the present work are very similar to those obtained in bulk silicon by earlier workers.
TL;DR: Heteroepitaxy of gallium phosphide on insulating substrates has been studied in this article, where undoped epitaxial films with thickness up to 25 μm have been successfully grown on (0001) and (1012) sapphire and on (111) spinel by the reaction between trimethyl gallium and phosphine using hydrogen as the carrier gas.
TL;DR: In this paper, the authors showed that recrystallized silicon became epitaxial with the substrate over the temperature range 800 to 1100 K and was accompanied by loss of conductivity by the specimen.
Abstract: Silicon implanted with 3 × 1014 20KeV phosphorus ions/cm2 was isochronally annealed at temperatures ranging from 600 K to 1250 K. Sheet resistivity measurements of the specimens were taken after each anneal, together with corresponding transmission electron micrographs. The increase in conductivity is explained in terms of a first order thermal reaction with an activation energy of 0.77 eV. The reaction rate for non-crystalline silicon produced by ion beam damage is shown to be about 40 times faster than for crystalline silicon, and occurs at temperatures below 900 K. The recrystallized silicon became epitaxial with the substrate over the temperature range 800 to 1100 K and was accompanied by loss of conductivity by the specimen. This process has been identified as a second order thermal reaction with an activation energy of 1–59 eV. Both reactions are discussed in terms of vacancy mechanisms. A study of the crystal defects in the recrystallized silicon reveals them to be either faulted or prisma...
TL;DR: In this paper, the deformation properties of GaxIn1−xAs and GaAsxP 1−x were investigated and it was found that there was an evident anisotropy of bending in the directions of 〈110 ǫ and 》110 ë, and this phenomenon cannot be explained by the simple bimetal model.
Abstract: Crystals of GaxIn1−xAs and GaAsxP1−x were deposited on GaAs substrate from the vapor phase, and the deformation properties of these systems accompanying the heteroepitaxial growth were investigated. When the crystal surface of the substrate was {100}, it was found that there was an evident anisotropy of bending in the directions of 〈110〉 and 〈110〉, and this phenomenon cannot be explained by the simple bimetal model. The influence of the crystalline surface of the substrate on the deformation was also checked.
TL;DR: In this paper, the mass spectrometric molecular beam technique has been used to measure the thermal accomodation coefficient, the kinetics and thermodynamics of adsorption and the extended growth of crystalline silver.
TL;DR: In this article, surface barrier diodes, using gold or palladium, have been fabricated on high purity material grown by liquid phase epitaxy, which has a thickness varying from 30 to 120?M and an electrically active impurity concentration varying from 5.1012 to 1.1014 per cc.
Abstract: Room temperature operating X and alpha ray spectrometers have been made with gallium arsenide. Surface barrier diodes, using gold or palladium have been fabricated on high purity material grown by liquid phase epitaxy. The epitaxial layers have a thickness varying from 30 to 120 ?M and an electrically active impurity concentration varying from 5.1012 to 1.1014 per cc. These layers deplete with only 8 volts reverse bias. Diodes of 4 to 8 mm2 area have given a resolution 15.5 kev FWHM on 5.48 MeV alpha particles at room temperature and 40 keV at 120°C. Similar devices have given a resolution of better than 5 keV FWHM on 60 keV X-rays at 25°C. The bulk generated currents are as low as 2.5 nanoamperes per cubic millimeter.
TL;DR: In this article, the epitaxial garnet films Y3−xEuxAlyFe5−y O12, with x=1.5−2.0 and y=0.7−1.2 and small additions of Yb, are reported: with 1−7μ bubbles; with bubble diameters that are relatively constant versus temperature; and in which bubble velocities greater than 1500 cm/sec have been observed.
Abstract: Epitaxial garnet films Y3−xEuxAlyFe5−y O12, with x=1.5–2.0 and y=0.7–1.2 and small additions of Yb, are reported: with 1–7‐μ bubbles; with bubble diameters that are relatively constant versus temperature; and in which bubble velocities greater than 1500 cm/sec have been observed. These materials show promise for bubble device applications.
TL;DR: In this article, the minimum substrate temperature required to form epitaxial layers by vapor deposition of Pd, Pt, Rh, and Ir on either Ir or Rh was determined to be 50, 100, 180, and 300°K using a field ion microscope.
Abstract: The minimum substrate temperature required to form epitaxial layers by vapor deposition of Pd, Pt, Rh, and Ir on either Ir or Rh is determined to be 50, 100, 180 and 300°K, respectively, using a field ion microscope. This shows that the minimum temperature increases with the binding energy of the deposited metal. It is suggested that a very few jumps before an incident atom settles in a site, plus the possible displacement of an adsorbed atom by an incident one, will give epitaxy in these fcc metals. Any involvement of foreign adsorbed atoms in the formation of epitaxy is ruled out by the good (<10−9 Torr) vacuum used in these experiments.