Abstract: A method of subliming material is provided for use in a CVD film preparation method wherein a CVD precursor is sublimed from its solid state by heating to a temperature not exceeding its melting point, thereby producing a vapor of the precursor, and the vapor of the precursor is transported to a reactor. The method of subliming material comprises the steps of forming the solid-state compound into a film, covering a back surface of the film with a non-reactive support and exposing a front surface of the film to an atmosphere as a sublimation surface. The method maintains the exposed surface area of the solid compound constant during processing.

Abstract: This invention provides an epitaxial growth method capable of decreasing variations of the resistance of an epitaxial layer resulting from an in-plane temperature distribution of a silicon wafer and also capable of reducing particles and haze. This epitaxial growth method is an epitaxial growth method of growing a boron- or phosphorus-doped silicon epitaxial layer on the surface of a silicon wafer with an in-plane temperature distribution of 2 to 50.degree. C., and includes the steps of arranging the silicon wafer in a reaction vessel, supplying into the reaction vessel a source gas containing (a) silane, (b) 5 to 600 vol % of hydrogen chloride added to the silane, and (c) a dopant consisting of a boron compound or a phosphorus compound, and growing a boron- or phosphorus-doped silicon epitaxial layer on the surface of the wafer by setting a vacuum degree of 10 to 200 torr in the reaction vessel and heating the wafer to 900 to 1100.degree. C.

Abstract: A method of manufacturing a semiconductor device which has a crystalline silicon film comprises the steps of forming crystal nuclei in a surface region of an amorphous silicon film and then growing the crystals from the nuclei by a laser light. Typically the crystal nuclei are silicon crystals or metal silicides having an equivalent structure as silicon crystal.

Abstract: Disclosed is a method of growing 4 gallium nitride-based crystal by vapor phase epitaxy, suitable for mass production, without the necessity of thermal processing after completion of the crystal growth. The temperature of the substrate crystal immediately after completion of the crystal growth is 700.degree. C. or higher, and cooling of the substrate crystal at 700.degree. C. or lower after completion of the crystal growth is performed in an atmosphere of a hydrogen-fee carrier gas.

Abstract: A planar waveguide and a process for making a planar waveguide is disclosed. The waveguide has a layer of dope host material formed on a substrate. The host material is a trivalent material such as a metal fluoride, wherein the metal is selected from the Group III B metals and the lanthanide series rare earth metals of the Mendeleevian Periodic Table. The dopant is a rare earth metal such as erbium. The waveguide has an emission spectrum with a bandwidth of about 60 nm for amplification of an optical signal at a wavelength of about 1.51 .mu.m to about 1.57 .mu.m. The waveguide is made by forming the layer of doped host material on a substrate. The film is formed by evaporating materials from two separate sources, one source for the dopant material and a separate source for the host material and forming a film of the evaporated materials on a substrate.

Abstract: The present invention relates to a method for growing new binary, ternary and quaternary epitaxial layers of III-V compound semiconductors which have the characteristics of low temperature growth, good stability and high-purity, using remote plasma, comprising the steps of converting H.sub.2 and He mixed gas into a plasma state; heating a high-purity of solid source to generate a vaporized source; reacting the vaporized source with H.sub.2 under the H.sub.2 and He plasma environment to produce V-hydrides in situ; introducing the V-hydrides directly into group III source without passing through the plasma; and reacting V-hydrides with group III source on a substrate to form an epitaxial thin layer of III-V compound semiconductors.

Abstract: A process for growing a single crystal comprises providing a single crystal substrate acting as a seed crystal above a source material in a container, heating the source material in an inert gas atmosphere in the container to form a sublimed source material, and discharging the sublimed source material from the container through a port above the single crystal substrate, to cause the sublimed source material to flow along and in parallel with a surface of the single crystal substrate, and grow a single crystal on the surface of the single crystal substrate.

Abstract: A method of growing 4-H polytype silicon carbide crystals in a physical vapor transport system where the surface temperature of the crystal is maintained at less than about 2160.degree. C. and the pressure inside the PVT system is decreased to compensate for the lower growth temperature.

Abstract: A process for producing high purity silicon carbide uses a high purity tetraethoxysilane or the like as the silicon source and a novolak-type phenol resin or the like as the carbon source. The process comprises a step of forming silicon carbide in which silicon carbide powder is prepared by calcining a mixture of these sources in a non-oxidizing atmosphere, and a step of post-treating silicon carbide in which the silicon carbide powder thus obtained is treated by heating at a temperature of 2000.degree. to 2100.degree. C. for 5 to 20 minutes at least once while the silicon carbide powder is kept at a temperature of 1700.degree. or higher to lower than 2000.degree. C., to obtain silicon carbide powder having an average particle diameter of 10 to 500 .mu.m and a content of impurity elements of 0.5 ppm or less. The high purity silicon carbide powder is advantageously used as a material for producing an excellent silicon carbide single crystal having a decreased number of crystal defects.

Abstract: A method for forming a crystal comprises applying a crystal forming treatment on a substrate having a free surface comprising a nonnucleation surface (S.sub.NDS) with small nucleation density and a nucleation surface (S.sub.NDL) exposed from said nonnucleation surface having a sufficiently small area for a crystal growing only from a single nucleus and having a greater nucleation density (ND.sub.L) than the nucleation density (ND.sub.S) of said non-nucleation surface (S.sub.NDS), thereby growing a single crystal from said single nucleus.

Abstract: A method of growing a single crystal thin film characterized by heating a silicon single crystal substrate placed in a reactor vessel, then while the temperature of the silicon single crystal substrate is 850.degree. C. or below, introducing a mixed gas composed of hydrogen fluoride gas and hydrogen gas into the reactor vessel for removing a native oxide film on a main surface of the silicon single crystal substrate in an ambient of hydrogen gas; and thereafter, growing a single crystal thin film by a vapor phase epitaxy on said main surface free from the native oxide film at a temperature of 1,000.degree. C. or below. With this method, both evaporation of a dopant caused by outdiffusion and autodoping can be suppressed with a substantial reduction of the processing time.

Abstract: A structure including a film of a desired perovskite oxide which overlies and is fully commensurate with the material surface of a semiconductor-based substrate and an associated process for constructing the structure involves the build up of an interfacial template film of perovskite between the material surface and the desired perovskite film. The lattice parameters of the material surface and the perovskite of the template film are taken into account so that during the growth of the perovskite template film upon the material surface, the orientation of the perovskite of the template is rotated 45.degree. with respect to the orientation of the underlying material surface and thereby effects a transition in the lattice structure from fcc (of the semiconductor-based material) to the simple cubic lattice structure of perovskite while the fully commensurate periodicity between the perovskite template film and the underlying material surface is maintained.

Abstract: The method of forming a III-V group compound semiconductor crystalline layer on a semiconductor crystal containing at least V-group compound, includes the steps of: performing the crystal growth of the III-V compound semiconductor crystalline layer; and supplying an n-type dopant and a material compound containing a V-group element onto the semiconductor crystal without causing the crystal growth of the III-V compound semiconductor crystalline layer.

Abstract: A lattice matching device includes a substrate having thereon monocrystal regions having different lattice mismatches with respect to a LnBa.sub.2 Cu.sub.3 O.sub.x superconductor. A superconducting thin film is formed on the substrate, which film consists essentially of a superconductor of LnBa.sub.2 Cu.sub.3 O.sub.x wherein Ln represents yttrium or a lanthanide, and 6<x<7. The first and second superconducting thin film portions have different axes of orientation perpendicular to a main surface of the substrate, and arranged in contact with each other or at a distance which allows transmission of electron pairs from one to another.

Abstract: Diamond film is deposited by chemical vapor deposition on the surface of a graphite mandrel which is covered with a protective coating to which the diamond film adheres. After completion of the deposition, the diamond is removed from the mandrel by sawing through the substrate to saw off a layer thereof which includes the deposition surface and the diamond film. The graphite and protective coating may be left in place for some applications or be removed either chemically or by mechanical abrasion to separate the diamond therefrom.

Abstract: A novel molecular beam epitaxy deposition process for precisely growing structurally robust films and coatings containing germanium and various fluoride compounds for use as an optical filter. The process comprises depositing two (2) materials having different indices of refraction via molecular beam epitaxy at a temperature significantly lower than the optimal growth temperature. At such lower temperature, layers of the respective compounds are grown, via molecular beam epitaxy, such that the layers contain large concentrations of dislocations. Once the film or coating has been grown to the desired thickness, the material deposited is allowed to cool to room temperature and may then be used in a wide range of applications.

Abstract: A graded layer composition of Zn(Se,Te) in which the Te fraction varies across the layer in a super-parabolic grading profile. Such a graded layer has lower contact resistance than graded layers in which the Te fraction varies in a linear or parabolic grading profile. Such low contact resistance makes such graded layers useful in forming ohmic contacts for II-VI semiconductor lasers and light emitting diodes.

Abstract: A diamond wafer including a substrate and a (100) oriented polycrystalline diamond film grown on the substrate for making surface acoustic wave devices, semiconductor devices or abrasion-resistant discs. The (100) oriented film is produced by changing a hydrocarbon ratio in a material gas halfway from a higher value to a lower value. The wafer is monotonously distorted with a distortion height H satisfying 2 .mu.m.ltoreq..vertline.H.vertline..ltoreq.150 .mu.m. The film is polished to a roughness of less than Rmax50 nm and Ra20 nm.

Abstract: The present invention relates to molecr beam epitaxy, in particular, to a gas source molecular beam epitaxy apparatus using compound gases as sources of semiconductor component elements, and also relates to a method for growing semiconductor crystal using this apparatus. It is an object of the present invention to prevent an epitaxial layer from being contaminated with organic compounds produced by decomposition of source gases. It is another object to grow a high purity semiconductor crystal at a growth rate high enough for practical applications. To achieve the above objects, in a growth apparatus in accordance with the present invention, the ambient gas pressure is maintained at the order of 10.sup.-5 -10.sup.-3 Torr during a growing process.

Abstract: An epitaxial growth method of semiconductor can reliably avoid irregularities from being produced when a II-VI compound semiconductor is grown epitaxially. When this method is applied to a method of manufacturing a semiconductor light-emitting device, it is possible to obtain a semiconductor light-emitting device having a long life and excellent light-emitting characteristic. When a II-VI compound semiconductor is grown epitaxially, a VI/II ratio, i.e., a supplying ratio of VI-group element and II-group element used in the epitaxial growth is selected in a range of from 1.3 to 2.5.

Abstract: The present invention includes a process of growing a compound semiconductor layer locally, after applying radical particles that do not become an etchant of a compound semiconductor layer to an insulating mask so as to terminate the surface of the insulating mask in a state that the compound semiconductor layer is covered with the insulating mask, on the surface of the compound semiconductor layer exposed from the insulating mask.

Abstract: A buffer layer having crystal orientation In a (111) face is formed on a semiconductor single-crystal (100) substrate and a ferroelectric thin film having crystal orientation in a (111) or (0001) face is then formed over the buffer layer. The buffer layer is preferably formed of MgO at a temperature ranging from 20.degree. to 600.degree. C. and at a rate ranging from 0.5 to 50 .ANG./sec. The thus formed ferroelectric thin film has its axes of polarization aligned in one direction. Using the oriented ferroelectric thin-film device, highly functional nonvolatile memories, capacitors or optical modulators can be fabricated on semiconductor substrates.

Abstract: In a method for growing a CdTe layer on a clean surface of a Si substrate, the clean surface of the Si substrate is subjected to an irradiation of As at a temperature in the range of about 650.degree. C. to about 800.degree. C. so that Si atoms on terrace of the clean surface are replaced by As atoms, followed by carrying out a molecular beam epitaxy to grow a CdTe layer on the surface. It is preferable that the clean surface is subjected to an irradiation of Cd in addition to the irradiation of As.

Abstract: A magnetic recording medium comprising a magnetic alloy layer having a bicrystal cluster microstructure and, hence, reduced medium noise, is formed by depositing a seed layer on a glass or a glass-ceramic material substrate, oxidizing the seed layer, depositing an underlayer, such as chromium, on the oxidized seed layer, whereby the underlayer exhibits a (200) crystallographic orientation. A magnetic alloy epitaxially grown on the underlayer having a (200) crystallographic orientation exhibits a bicrystal cluster microstructure.

Abstract: Disclosed herein is a selective metalorganic vapor phase growth method of a group III-V compound semiconductor containing at least Al and In, in which a ratio of an HCl gas supply amount to a supply amount of a group III metalorganic material (?HCl supply amount!/?group III supply amount!) is set in a range of 0.01-0.3. Hence, a polycrystal density is decreased to ensure a selectivity, and a grown crystal composition can be controlled so as not to be excessive in the Al composition so that composition control can be done easily.

Abstract: A cycle of alternately or cyclically introducing external gases containing molecules of component elements of a compound semiconductor to be formed on a substrate is repeated while appropriately controlling the pressure, substrate temperature and gas introduction rate in a crystal growth vessel, so that a monocrystal which is dimensionally as precise as a single monolayer can grow on the substrate by making use of chemical reactions on the heated substrate surface.Doped molecular layer epitaxy of a compound semiconductor comprising individual steps of introducing and evacuating a first source gas, introducing and evacuating a second source gas, and introducing and evacuating an impurity gas which contains an impurity element. The doped impurity concentration varies almost linearly with the pressure during doping in a wide range.

Abstract: A crystal is formed by applying crystal forming treatment to a substrate, the surface of the substrate being divided into nonnucleation surface exhibiting a small nucleation density and nucleation surface having a sufficeintly small area to allow crystal growth from a single nucleus and exhibiting a larger nucleation density than the nonnucleation surface and the nonnucleation surface being constituted of the surface of a buffer layer to alleviate generation of stress in the crystal formed.

Abstract: The present invention has been achieved by perceiving the fact to the effect that a semiconductor production process-like manner such as CVD method or the like by which materials and film thickness can be controlled in an atomic scale may be utilized in case of preparing thin-film crystal, and employing such semiconductor production process-like manner being quite different from conventional technique.

Abstract: An epitaxial growth system comprises a housing around an epitaxial growth chamber. A substrate support is located within the growth chamber. A gallium source introduces gallium into the growth chamber and directs the gallium towards the substrate. An activated nitrogen source introduces activated nitrogen into the growth chamber and directs the activated nitrogen towards the substrate. The activated nitrogen comprises ionic nitrogen species and atomic nitrogen species. An external magnet and/or an exit aperture control the amount of atomic nitrogen species and ionic nitrogen species reaching the substrate.

Abstract: A method for making a set of surface-emitting laser diodes comprises the making of reflectors by the epitaxial growth of at least one semiconductor material through a mask having apertures with inclined flanks. This method leads to the obtaining of the Bragg reflectors obtained in situ, removing the need for the ion etching of a semiconductor substrate followed by a phase for the conditioning of the surface of the sample before the preparation of the desired laser structure.Application: optical power source.

Abstract: A method for making oriented thin films of a ternary intermetallic compound and such films having a tetragonal structure and generally uniaxial magnetic, optical, electronic, and mechanical properties, as well as a generally lower Curie temperature than oriented binary intermetallic films. The steps of the method involve selecting a substrate material for biasing the orientation of the ternary intermetallic compound and exhibiting no chemical reactiveness to the ternary intermetallic compound. Preferably, such substrate is a single crystal, such as MgO or Al.sub.2 O.sub.3, or an amorphous material such as pure SiO.sub.2, amorphous carbon, or glass. In a second step the substrate is heated to a temperature above 450.degree. C. and then, a first metal, a second metal, and a third metal are simultaneously deposited on the substrate material.

Abstract: A flat free-standing diamond film is produced by growing alternately at least one pair of a potential-concave diamond layer and a potential-convex diamond layer on a non-diamond substrate and eliminating the substrate. The potential-concave films are made by a CVD method under a condition (b), which is characterized by of a substrate temperature of 880.degree. C. to 950.degree. C. and a hydrocarbon ratio of 2.5 vol % to 3.5 vol %. The potential-convex films are made by a CVD method under the condition (a) which is charcterized by of a substrate temperature of 800.degree. C. to 850.degree. C. and a hydrocarbon ratio of 0.5 vol % to 1.5 vol %. The condition (a) can make a potential-convex film of a good crystal quality in spite of a slow deposition speed. It is preferable to employ an assembly of thinner potential-convex films and thicker potential-concave films to curtail the total time of synthesis.

Abstract: A novel method is proposed for the preparation of a superlattice multilayered film, which has a multilayered structure alternately consisting of epitaxially grown layers of a metal and layers of a metal oxide formed on the surface of a substrate and is useful as high-speed electronic devices, soft X-ray reflectors, neutron beam polarizers and the like. According to the discovery leading to this invention, good epitaxial growth of the layers can be accomplished when the metal has a face-centered cubic lattice structure and the metal oxide has a sodium chloride-type cubic lattice structure and the difference in the lattice constant between the metal and the metal oxide is small enough as in the combinations of silver and nickel oxide or magnesium oxide and nickel and nickel oxide.

Abstract: A deposition method of a compound semiconductor forming a semiconductor device comprises the steps of; covering the surface of a compound semiconductor containing a V group element with a III group element with a thickness of one or more monolayers; and forming a second compound semiconductor containing a V group element different from said V group element on said III group element while utilizing said III group element as a protective film for preventing the desorption of said V group element.

Abstract: A doped or undoped photoresponsive material having metallic precipitates, and a PiN photodiode utilizing the material for detecting light having a wavelength of 1.3 micrometers. The PiN photodiode includes a substrate having a first compound semiconductor layer disposed thereon. The PiN photodiode further includes an optically responsive compound semiconductor layer disposed above the first compound semiconductor layer. The optically responsive layer includes a plurality of buried Schottky barriers, each of which is associated with an inclusion within a crystal lattice of a Group III-V material. The PiN device also includes a further compound semiconductor layer disposed above the optically responsive layer. For a transversely illuminated embodiment, waveguiding layers may also be disposed above and below the PiN structure. In one example the optically responsive layer is comprised of GaAs:As.

Abstract: In a method of and an apparatus for epitaxially growing a chemical-compound crystal, a plurality of raw-material gasses are alternately introduced into a closed chamber of a crystal growing device to grow the crystal placed within the closed chamber. At growing of the crystal, a light from a light source is emitted to a crystal growing film of the crystal. Intensity of a light reflected from the crystal growing film and received by a photo detector is measured. Charge amounts of the respective raw-material gasses are controlled by a control system on the basis of a change in the reflected-light intensity, thereby controlling a growing rate of the growing film.

Abstract: A method of growing a first SiC single crystal on a seed crystal including a second SiC single crystal, comprises the steps of setting a SiC source material at an initial temperature, growing the first SiC single crystal on the seed crystal including the second SiC single crystal at a temperature lower than the initial temperature of the source material and gradually decreasing the source material temperature from the initial temperature during at least a predetermined period during the growing step.

Abstract: A technique of heteroepitaxially growing compound semiconductor on a silicon wafer, which can simplify the growth sequence, and improve the productivity and the surface morphology of a growth film. In growing compound semiconductor on a silicon wafer, the growth sequence such as shown in FIG. 1 is used. A necessary thin buffer layer is continuously grown at the temperature raising period up to the crystal growth temperature. Therefore, an independent process of growing a buffer layer at a lower temperature is not necessary, and the surface morphology is also improved by this method of growing compound semiconductor on a silicon wafer.

Abstract: A method for making layered structures of artificial high T.sub.c superconductor compounds by which on top of a seed crystal having a lattice structure matching the lattice structure of the superconductor compound to be made, oxide layers of all constituent components are epitaxially grown in a predetermined sequence so as to create a sandwich structure not found in natural crystals. The epitaxial deposition of the constituent components is performed in a reaction chamber having evaporation facilities, inlets for metal-organic gases, and inlets for background gases including oxygen.

Abstract: In the manufacture of a single crystal film by epitaxial growth method, defects such as cracking are avoided by increasing the deviation of the lattice constant of the resulting film in the direction of growth from the substrate. Preferably, the deviation is increased at the rate of (0.4.about.9).times.10.sup.-4 %/.mu.m.

Abstract: A metal-organic chemical vapor-phase deposition process for fabricating a layer of a Group II-VI compound semiconductor using an organometallic compound based on bis(cyclopentadienyl)magnesium having a vapor pressure in the range of from 1.3.times.10 Pa to 1.3.times.10.sup.2 Pa at a temperature of 330.degree. K. The present invention also provides a light-emitting device which is fabricated by means of the metal-organic vapor-phase deposition process above. The process according to the present invention provides a magnesium-containing compound semiconductor layer having an accurately controlled composition, and it readily enables the fabrication of a compound semiconductor layer having a grated structure.

Abstract: A method of depositing a gallium nitride-based III-V Group compound semiconductor crystal layer over a substrate by a metalorganic chemical vapor deposition technique. A reaction gas is supplied to a surface of a heated substrate in a direction parallel or oblique to the substrate. The gallium nitride-based III-V Group compound semiconductor crystal layer is grown on the heated substrate, while introducing a pressing gas substantially in a vertical direction toward the substrate to press the reaction gas against the entire surface of the substrate, under atmospheric pressure or a higher pressure.

Abstract: There is provided a method of producing a high-quality n-type, 6H silicon carbide single crystal with good reproducibility. A silicon carbide single crystal substrate having a growth orientation of <0001>, as a seed crystal, is mounted to an inner surface of a cover of a graphite crucible. A source material includes a high-purity silicon carbide powder having an impurity proportion of not more than 1 ppm and an aluminum powder of 50 ppm relative to the silicon carbide powder. The source material is loaded into the graphite crucible. The graphite crucible is closed with a seed crystal-mounted cover placed in a double quartz tube. Ar gas and N.sub.2 gas are caused to flow in the double quartz tube. Temperature of the silicon carbide powder and aluminum powder is controlled to 2300.degree. C., and temperature of the silicon carbide single crystal substrate to 2200.degree. C.; and interior of the double quartz tube is controlled to 30 torr.

Abstract: A method of manufacturing a semiconductor device according to the present invention comprises the steps of forming a conductive film on an insulating film, forming growth nucleuses containing any of elements in group IIIb, group IVb, group Vb and group VIIb that does not constitute the conductive film and the insulating film on the surface of the conductive film, and growing a semiconductor selectively on growth nucleuses.

Abstract: A method of fabricating a plurality of optoelectronic components on a semiconductor substrate, each optoelectronic component comprising several layers grown in a reactor. Every layer is being grown under a predetermined individual pressure. The active layers of all the components are lying substantially at the same height. Control of the pressure in the reactor during growth allows the thickness of the layer grown to be constant or to vary over the substrate area.

Abstract: A ferromagnetic .delta.-Mn.sub.1-x Ga.sub.x thin film having perpendicular anisotropy is described which comprises: (a) a GaAs substrate, (b) a layer of undoped GaAs overlying said substrate and bonded thereto having a thickness ranging from about 50 to about 100 nanometers, (c) a layer of .delta.-Mn.sub.1-x Ga.sub.x overlying said layer of undoped GaAs and bonded thereto having a thickness ranging from about 20 to about 30 nanometers, and (d) a layer of GaAs overlying said layer of .delta.-Mn.sub.1-x Ga.sub.x and bonded thereto having a thickness ranging from about 2 to about 5 nanometers, wherein x is 0.4 .+-.0.05.

Abstract: A new method for accurately and sequentially growing monolayers and creating new superlattice structures employing a MBE thermal source control technique employing a quasi-double beam atomic absorption background correction measurements with the beam blocked and with the beam unblocked and by calculating the concentration based on the: ##EQU1## and applying corrections for non-linear absorption curves because of comparable spectral bandwidth of the molecular beam.

Abstract: Thin films of cubic boron nitride carbide are provided on an underlying silicon substrate. The cubic boron nitride carbide films are deposited using laser ablation methods. The boron nitride film has a crystallographic lattice constant which can be varied depending upon the desired film composition and processing parameters. Preferably, the resulting thin film composition is characterized by a chemical formula of (BN).sub.1-x C.sub.x where x is about 0.2. The resulting films are particularly suitable for wear resistance and semiconducting applications over a wide range of temperatures.

Abstract: A single-crystal substrate is prepared which has the (100) crystal plane with a step line formed therein by cleaving an MgO single crystal. By evaporating metal onto the cleavage plane, with a mask wire of platinum disposed at a distance from the cleavage plane and extended in a direction across the step line, a pair of metal thin film electrodes separated by a gap are epitaxially grown. By this, a step line corresponding to the cleavage-plane step line is formed in the surface of each of the metal thin film electrodes. Metal is further evaporated onto the metal thin film electrodes at a low rate, by which nano-size thin wires extending along the step lines are grown so that they approach each other and are finally connected to each other.

Abstract: The present invention is a method of forming large device quality single crystals of silicon carbide. The sublimation process is enhanced by maintaining a constant polytype composition in the source materials, selected size distribution in the source materials, by specific preparation of the growth surface and seed crystals, and by controlling the thermal gradient between the source materials and the seed crystal.