Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: After a Group III-V compound semiconductor layer, to which a p-type dopant has been introduced, has been formed over a substrate, the compound semiconductor layer is annealed. In the stage of heating the compound semiconductor layer, atoms, deactivating the p-type dopant, are eliminated from the compound semiconductor layer by creating a temperature gradient in the compound semiconductor layer.

Abstract: A novel method for growing semiconductor material including GaN is disclosed. The method involves placing a first substance into a growth reactor, supplying a second gaseous substance into the grouth reactor, and applying electrical field to the second gaseous substance to produce the cry stalline compound material.

Abstract: A method for fabricating p-type, i-type, and n-type III-V compound materials using HVPE techniques is provided. If desired, these materials can be grown directly onto the surface of a substrate without the inclusion of a low temperature buffer layer. By growing multiple layers of differing conductivity, a variety of different device structures can be fabricated including simple p-n homojunction and heterojunction structures as well as more complex structures in which the p-n junction, either homojunction or heterojunction, is interposed between a pair of wide band gap material layers. The provided method can also be used to fabricate a device in which a non-continuous quantum dot layer is grown within the p-n junction. The quantum dot layer is comprised of a plurality of quantum dot regions, each of which is typically between approximately 20 and 30 Angstroms per axis.

Abstract: The invention aims to provide a hard film which is improved in high-temperature corrosion resistance without impairing high sliding characteristics (wear resistance, low frictional coefficient) inherent in a titanium nitride thin film and which is suitable for a slide member such as a bearing or a seal used in rotary machines operated at a high temperature, such as a steam turbine and a gas turbine. For attaining this aim, the invention provides a Cr-containing titanium nitride film which is composed of a nitride containing Ti and Cr as main components, the crystal particles thereof having a face-centered cubic crystal structure, and the crystal thereof being highly oriented toward (200) face.

Abstract: An AlxGayInzN(x+y+z=1,x,y,z≧0) film is epitaxially grown, for example to a thickness of about 1.0 &mgr;m, on a surface of a base material. A surface of the AlxGayInzN film opposing the base material is polished and thus, flattened to have a surface roughness Ra of less than 10 Å and a thickness of about 1.0 &mgr;m. A high crystallinity nitride film is interposed between the base material and the AlxGayInzN film.

Abstract: A method for fabricating p-type, i-type, and n-type III-V compound materials using HVPE techniques is provided. If desired, these materials can be grown directly onto the surface of a substrate without the inclusion of a low temperature buffer layer. By growing multiple layers of differing conductivity, a variety of different device structures can be fabricated including simple p-n homojunction and heterojunction structures as well as more complex structures in which the p-n junction, either homojunction or heterojunction, is interposed between a pair of wide band gap material layers. The provided method can also be used to fabricate a device in which a non-continuous quantum dot layer is grown within the p-n junction. The quantum dot layer is comprised of a plurality of quantum dot regions, each of which is typically between approximately 20 and 30 Angstroms per axis. The quantum dot layer is preferably comprised of AlxByInzGa1-x-y-zN, InGaN1-a-bPaAsb, or AlxByInzGa1-x-y-zN1-a-bPaAsb.

Abstract: A method of producing silicon carbide (SiC), by introducing into the interior of a furnace a quantity of relatively pure elemental silicon and a quantity of elemental carbon; subjecting the interior of the furnace to a vacuum; and heating the silicon and carbon to a temperature of 1500° C.-2200° C. to vaporize the silicon and to react it with the carbon to produce silicon carbide. Several embodiments are described for producing a heating or lighting element and a high temperature sensor, respectively, in which the carbon is in the form of a shaped body made of a mixture of finely-divided particles of carbon in a binder, and the silicon is in the form of finely-divided particles applied to the outer surface of the shaped body. A further embodiment is described for producing silicon carbide powder, in which the carbon and silicon are each in the form of finely-divided particles, and are physically separated from each other by a graphite sheet permeable to silicon vapor.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: The method for fabricating a semiconductor device of this invention includes the step of: forming a first compound semiconductor layer by crystal growth on a surface of a semiconductor substrate which includes a plurality of crystal planes having different orientations exposed due to a concave portion and/or a convex portion formed on the semiconductor substrate, the first compound semiconductor layer containing nitrogen and a V group element other than nitrogen.

Abstract: A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated.

Abstract: A susceptor is disclosed for minimizing or eliminating thermal gradients that affect a substrate wafer during epitaxial growth. The susceptor comprises a first susceptor portion including a surface for receiving a semiconductor substrate wafer thereon, and a second susceptor portion facing the substrate-receiving surface and spaced from the substrate-receiving surface. The spacing is sufficiently large to permit the flow of gases therebetween for epitaxial growth on a substrate on the surface, while small enough for the second susceptor portion to heat the exposed face of a substrate to substantially the same temperature as the first susceptor portion heats the face of a substrate that is in direct contact with the substrate-receiving surface.

Abstract: A GaN boule is epitaxially grown by reacting a vapor of the metal Ga with the gas NH3 at a high temperature of about 1200-degrees C., which high temperature causes the NH3 to dissociate into the two elements N and H. A seed 51 of GaN is placed within a growth-furnace that is heated to about 1200-degrees C., and an input stream of Ga vapor and NH3 gas are directed incident on the GaN seed. An upward-facing, shower head-shaped, manifold is provided to uniformly distribute the Ga vapor and the NH3 gas to the interior of the growth-furnace at a location that is generally below and spaced from the bottom of the GaN seed. GaN vapor is thus formed within this space, generally adjacent to the surface of the boule. At the exterior surface of the GaN seed, the Ga vapor reacts with the NH3 gas to epitaxially form solid GaN on the exterior surface of the GaN seed, and to also form H2.

Abstract: The inventive method exploits the fact that in solutions or melts which contain certain organic substances, small nitride crystallites consisting of GaN or AlN are formed by thermal reaction and decomposition. A vessel containing the melt is kept at a first temperature T1. In the vessel is a substrate nucleus of he nitride to be formed, which is heated to second temperature T2 through the input of energy, where T2>T1. Epitaxial growth from the melt then takes place on the surface of the substrate nucleus. The energy input can be carried out in different ways.

Abstract: An improved apparatus and method for substrate layer deposition in which substrate layers are grown by carrier gas delivery of sequential pulses of reactants to the substrate surface. At least one of the reactants comprises excited species, e.g., radicals. In a specific embodiment, the apparatus of this invention provides sequential repeated pulses of reactants in a flow of carrier gas for reaction at a substrate surface. The reactant pulses are delivered with sufficient intervening delay times to minimize undesirable reaction between reactants in adjacent pulses in the gas phase or undesired uncontrolled reactions on the substrate surface.

Abstract: A method of fabricating a group III-V nitride compound semiconductor in which high crystallinity is achieved without lack of nitrogen, even when it is grown at a low temperature, and a method of fabricating a semiconductor device employing the method of fabricating a group III-V nitride compound semiconductor are provided. Along with carrier gas, a gas source including a nitrogen-including compound such as hydrazine, a substitution product of hydrazine, amine or azide as a nitrogen source is supplied to a reaction tube of a MOCVD apparatus. These nitrogen-including compounds have higher decomposition efficiencies than those of ammonia. Therefore, even though MOCVD is performed at a growth temperature below or equal to 900° C., a large amount of nitrogen which contributes growth is supplied onto the growth surface of a substrate (that is, an underlying layer). As a result, crystallinity of the group III-V nitride compound semiconductor layer is improved.

Abstract: This invention relates to a method of growing a nitride semiconductor layer by molecular beam epitaxy comprising the steps of: a) heating a GaN substrate (S) disposed in a growth chamber (10) to a substrate temperature of at least 850° C.; and b) growing a nitride semiconductor layer on the GaN substrate by molecular beam epitaxy at a substrate temperature of at least 850° C., ammonia gas being supplied to the growth chamber (10) during the growth of the nitride semiconductor layer; wherein the method comprises the further step of commencing the supply ammonia gas to the growth chamber during step (a), before the substrate temperature has reached 800° C.

Abstract: When nitride series III-V group compound semiconductor is manufactured by gas phase growing using starting material for a group III element, ammonia as a starting material for a group V element and hydrogen, the gas phase molar ratio of hydrogen to the total amount of hydrogen and ammonia (H2/(H2+NH3)) is specified to 0.3<(H2/(H2+NH3))<0.7, 0.3<(H2/(H2+NH3))<0.6 or 0.4<(H2/(H2+NH3))<0.5. A nitride series III-V group compound semiconductor can thus be manufactured with less non-emission center and of excellent crystallinity.

Abstract: A GaN single crystal is grown by synthesizing GaN in vapor phase, piling a GaN crystal on a substrate, producing a three-dimensional facet structure including facets in the GaN crystal without making a flat surface, maintaining the facet structure without burying the facet structure, and reducing dislocations in the growing GaN crystal. The facet structure reduces the EPD down to less than 106 cm−2.

Abstract: A III-V nitride homoepitaxial microelectronic device structure comprising a III-V nitride homoepitaxial epi layer on a III-V nitride material substrate, e.g., of freestanding character. Various processing techniques are described, including a method of forming a III-V nitride homoepitaxial layer on a corresponding III-V nitride material substrate, by depositing the III-V nitride homoepitaxial layer by a VPE process using Group III source material and nitrogen source material under process conditions including V/III ratio in a range of from about 1 to about 105, nitrogen source material partial pressure in a range of from about 1 to about 103 torr, growth temperature in a range of from about 500 to about 1250 degrees Celsius, and growth rate in a range of from about 0.1 to about 500 microns per hour. The III-V nitride homoepitaxial microelectronic device structures are usefully employed in device applications such as UV LEDs, high electron mobility transistors, and the like.

Abstract: A freestanding GaN single crystal substrate is made by the steps of preparing a (111) GaAs single crystal substrate, forming a mask having periodically arranged windows on the (111) GaAs substrate, making thin GaN buffer layers on the GaAs substrate in the windows of the mask, growing a GaN epitaxial layer on the buffer layers and the mask by an HVPE or an MOC, eliminating the GaAs substrate and the mask away and obtaining a freestanding GaN single crystal substrate. The GaN single crystal has a diameter larger than 20 mm and a thickness more than 0.07 mm, being freestanding and substantially distortion-free.

Abstract: A new and improved method for growing a p-type nitride III-V compound semiconductor is provided which can produce a p-type nitride compound semiconductors having a high carrier concentration, without the need for annealing to activate impurities after growth. In a preferred embodiment, a p-type nitride compound semiconductor, such as p-type GaN, is grown by metal organic chemical vapor deposition methods using a nitrogen source material which does not release hydrogen during release of nitrogen and the semiconductor is grown in an inactive gas. The nitrogen source materials may be selected from nitrogen compounds that contain hydrogen radicals and alkyl radicals and/or phenyl radicals provided that the total amount of hydrogen radicals is less than or equal to the sum total of alkyl radicals and phenyl radicals present in the nitrogen compound used as the nitrogen source material.

Abstract: This invention provides a process and apparatus for producing products of M-nitride materials wherein M=gallium (GaN), aluminum (AlN), indium (InN), germanium (GeN), zinc (ZnN) and ternary nitrides and alloys such as zinc germanium nitride or indium aluminum gallium nitride. This process and apparatus produce either free-standing single crystals, or deposit layers on a substrate by epitaxial growth or polycrystalline deposition. Also high purity M-nitride powders may be synthesized. The process uses an ammonium halide such as ammonium chloride, ammonium bromide or ammonium iodide and a metal to combine to form the M-nitride which deposits in a cooler region downstream from and/or immediately adjacent to the reaction area. High purity M-nitride can be nucleated from the vapor to form single crystals or deposited on a suitable substrate as a high density material.

Abstract: The invention concerns a method for epitaxial growth of a material on a first solid material from a material melting on the material, characterized in that it comprises: a step of growth of the first material on the substrate, made of a second material; a step whereby crystalline tips of the first material are made to grow from the contact surface between the first material and the melting material; a step which consists in causing crystals to grow laterally from the crystalline tips in a plane parallel to that of the free surface of the melting material.

Abstract: A gallium nitride growth process forms crystalline gallium nitride. The process comprises the steps of providing a source gallium nitride; providing mineralizer; providing solvent; providing a capsule; disposing the source gallium nitride, mineralizer and solvent in the capsule; sealing the capsule; disposing the capsule in a pressure cell; and subjecting the pressure cell to high pressure and high temperature (HPHT) conditions for a length of time sufficient to dissolve the source gallium nitride and precipitate the source gallium nitride into at least one gallium nitride crystal. The invention also provides for gallium nitride crystals formed by the processes of the invention.

Abstract: The present invention comprises growing gallium nitride films in the presence of bismuth using MBE at temperatures of about 1000 K or less. The present invention further comprises the gallium nitride films fabricated using the inventive fabrication method. The inventive films may be doped with magnesium or other dopants. The gallium nitride films were grown on sapphire substrates using a hollow anode Constricted Glow Discharge nitrogen plasma source. When bismuth was used as a surfactant, two-dimensional gallium nitride crystal sizes ranging between 10 &mgr;m and 20 &mgr;m were observed. This is 20 to 40 times larger than crystal sizes observed when GaN films were grown under similar circumstances but without bismuth. It is thought that the observed increase in crystal size is due bismuth inducing an increased surface diffusion coefficient for gallium. The calculated value of 4.7×10−7 cm2/sec. reveals a virtual substrate temperature of 1258 K which is 260 degrees higher than the actual one.

Abstract: Apparatus for bulk vapor phase crystal growth comprising: at least one source zone and at least one sink zone each associated with means for independent temperature control within the zone; and at least one passage means adapted for transport of vapor from source to sink zone; and additionally comprising means for in-situ monitoring of the sink zone; wherein means for monitoring is substantially non-intrusive in terms of temperature regulation within the sink zone; process for bulk vapor phase crystal growth employing the apparatus; method for starting up the process; method for controlling the process; use for any bulk vapor transport technique; equipment for monitoring growth using the apparatus or process; and crystal grown with the apparatus or process.

Abstract: The subject invention pertains to a method and device for producing large area single crystalline III-V nitride compound semiconductor substrates with a composition AlxInyGa1-x-y N (where 0≦x≦1, 0≦y≦1, and 0≦x+y≦1). In a specific embodiment, GaN substrates, with low dislocation densities (˜107 cm2) can be produced. These crystalline III-V substrates can be used to fabricate lasers and transistors. Large area free standing single crystals of III-V compounds, for example GaN, can be produced in accordance with the subject invention. By utilizing the rapid growth rates afforded by hydride vapor phase epitaxy (HVPE) and growing on lattice matching orthorhombic structure oxide substrates, good quality III-V crystals can be grown. Examples of oxide substrates include LiGaO2, LiAlO2, MgAlScO4, Al2MgO4, and LiNdO2. The subject invention relates to a method and apparatus, for the deposition of III-V compounds, which can alternate between MOVPE and HVPE, combining the advantages of both.

Abstract: The Group III-V compound semiconductor manufacturing method which pertains to the present invention is a semiconductor manufacturing method employing epitaxy which comprises (a) a step in which growing areas are produced using a mask patterned on a substrate surface and (b) a step in which a Group III-V compound semiconductor layer is grown in the growing areas while forming facet structures. As epitaxy is continued, adjacent facet structures come into contact so that the surface of the semiconductor layer becomes planarized. Since lattice defects extend towards the facet structures, they do not extend towards the surface of the semiconductor layer. Accordingly, the number of lattice defects in the vicinity of the semiconductor layer surface is reduced.

Abstract: A piezoelectric single crystal wafer for SAW or LSAW devices has an x-ray rocking curve half width of up to 0.06° on the wafer surface on which electrodes are to be formed for transmitting and receiving SAW or LSAW.

Abstract: The invention concerns a method for producing a gallium nitride (GaN) epitaxial layer characterised in that it consists in depositing on a substrate a dielectric layer acting as a mask and depositing on the masked gallium nitride, by epitaxial deposit, so as to induce the deposit of gallium nitride patterns and the anisotropic lateral growth of said patterns, the lateral growth being pursued until the different patterns coalesce. The deposit of the gallium nitride patterns can be carried out ex-situ by dielectric etching or in-situ by treating the substrate for coating it with a dielectric film whereof the thickness is of the order of one angstrom. The invention also concerns the gallium nitride layers obtained by said method.

Abstract: A GaN layer is grown on a sapphire substrate, an SiO2 film is formed on the GaN layer, and a GaN semiconductor layer including an MQW active layer is then grown on the GaN layer and the SiO2 film using epitaxial lateral overgrowth. The GaN based semiconductor layer is removed by etching except in a region on the SiO2 film, and a p electrode is then formed on the top surface of the GaN based semiconductor layer on the SiO2 film, to join the p electrode on the GaN based semiconductor layer to an ohmic electrode on a GaAs substrate. An n electrode is formed on the top surface of the GaN based semiconductor layer.

Abstract: Disclosed is a method for manufacturing a high conductivity p-type GaN-based thin film superior in electrical and optical properties by use of nitridation and RTA (rapid thermal annealing) in combination. A GaN-based epitaxial layer is grown to a desired thickness while being doped with Mg dopant with a carrier gas of hydrogen by use of a MOCVD process. The film thus obtained is subjected to nitridation using nitrogen plasma and RTA in combination. The p-type GaN-based thin film exhibits high hole concentration as well as low resistivity, so that it can be used where high electrical, optical, thermal and structural properties are needed. The method finds application in the fabrication of blue/white LEDs, laser diodes and other electronic devices.

Abstract: A method for forming a relatively thick epitaxial film of a III-V compound on a non-native substrate involves sequentially forming a plurality of epitaxial layers on the substrate at a growth temperature. By cooling the substrate and each sequentially grown epitaxial layer to a sub-growth temperature prior to resumption of epitaxial growth, stress within the sample (due to thermal mismatch between the substrate and the epitaxial layer) is periodically relieved. Sequential epitaxial growth is combined with system etching to provide an epitaxial layer which not only has a lower propensity to shatter, but also exhibits improved surface morphology. Sequential hydride vapor-phase epitaxy using HCl as both source gas and etchant, allows integration of sequential deposition and system etching into a single process.

Abstract: A MOVPE method is provided that makes it possible to grow a high-quality nitride crystal of a group III element. The method comprises the steps (a) to (d). In the step (a), an organometallic compound in a gas phase is supplied to a reaction chamber as a group III component material by a carrier gas. In the step (b), a nitrogen compound in a gas phase is supplied to the chamber as a group V component material by the carrier gas. In the step (c), a hydrocarbon in a gas phase is supplied to the chamber by the carrier gas. In the step (d), the organometallic compound and the nitrogen compound are reacted with each other in a atmosphere containing the hydrocarbon in the chamber to grow a nitride crystal of a group III element on a crystalline substrate. As the hydrocarbon, any hydrocarbon containing at least one carbon-to-carbon (i.e., C—C) bond in its molecule (i.e., alkanes) may be used. Preferably, any hydrocarbon containing at least one double or triple carbon-to-carbon bond (i.e.

Abstract: The method of fabrication of highly resistive GaN bulk crystals by crystallization from the solution of atomic nitrogen in the molten mixture of metals, containing gallium in the concentration not lower than 90 at. % and the Periodic Table group II metals: calcium, beryllium or in the concentration of 0.01-10 at. %, at the temperature 1300-1700° C., under the nitrogen pressure 0.5-2.0 GPa and in the presence of temperature gradient characterized by the temperature gradient not higher than 10° C./cm.

Abstract: A Group III metal element is heated so as to melt, a gas NH3 containing nitrogen atoms is injected into a melt 3 of the Group III metal element at a temperature lower than the melting point of a nitride to be obtained, thereby producing a nitride microcrystal of the Group III element having high wettability with the melt 3 in the melt 3 of the Group III metal element. A mixture of the Group III nitride microcrystal obtained as mentioned above and the Group III metal element solution is used as a starting material of a liquid phase growth or Group III nitride powders obtained by removing the Group III metal material from the mixture are used as a starting material of a vapor phase growth.

Abstract: A method of growing a Group III-V nitrite buffer layer on a substrate made of a different material by molecular beam epitaxy is provided, which compensates for lattice mismatching between a material of the substrate and a material of a further layer to be grown on the substrate. The method includes the steps of: placing the substrate in a vacuum chamber at a reduced pressure suitable for epitaxial growth and at an elevated temperature; and supplying species to the vacuum chamber to be used in the epitaxial growth including a nitrogen precursor species supplying nitrogen to the substrate to cause epitaxial growth on the substrate of the buffer layer. The elevated temperature is in the range of 300 to 800 ° C., and a supply rate of nitrogen to the substrate is such as to cause epitaxial growth on the substrate of the Group III-V nitride buffer layer of uniform thickness less than 2000 Å at a growth rate in the range of 2 to 10 &mgr;m/hr.

Abstract: A device made of a III-V nitride compound semiconductor comprising a substrate of sapphire, a Si single crystal, a GaAs single crystal, or a GaP single crystal; a GaN single crystal film with a thickness not greater than 3 nm formed on the substrate; and at least one layer of a III-V nitride compound semiconductor formed on the GaN single crystal film. Also a device made of a III-V nitride compound semiconductor comprising a Si single crystal substrate having a natural oxide film; a SiOn film formed by partially nitriding the natural oxide film; and a layer of a III-V nitride compound semiconductor formed on the SiON film.

Abstract: The present invention relates to a process for the application of an epitactic GaN layer to a substrate by pyrolysis of precursor compounds.

Abstract: A process is disclosed for producing pn junctions and p-i-n junctions from group III nitride compound semiconductor materials. The process comprises growing of pn junctions and p-i-n junctions by hydride vapor phase epitaxy employing hydride of nitrogen (ammonia, hydrozine) as a source of nitrogen and halides of group III metal as a source of metal. Mg is used as acceptor impurity to form p-type III-V nitride layers. The preferred sources for Ga and Al are Ga and Al metals, respectively. The process is carried out in the temperature range from 900 to 1200° C.

Abstract: Metal nitrate-containing precursor compounds are employed in atomic layer deposition processes to form metal-containing films, e.g. metal, metal oxide, and metal nitride, which films exhibit an atomically abrupt interface and an excellent uniformity.

Abstract: Method for forming a single crystal GaN semiconductor substrate and a GaN diode with the substrate is disclosed which forms in a short time period, has a low crystal defect concentration and allows forming a size large enough to fabricate an optical device, the method including either the steps of fast growth of a GaN group material on an oxide substrate to a thickness without cracking and subjecting to mechanical polish to remove a portion of the oxide substrate, and growing GaN again on the grown GaN layer and complete removal of the remaining oxide substrate to obtain a GaN film, or the steps of separating the oxide substrate from the GaN layer utilizing cooling to obtain a GaN film, grown GaN on the GaN film to a predetermined thickness to form a GaN bulk single crystal and mirror polishing it to form the GaN single crystal substrate, whereby a defectless GaN single crystal substrate of a size required for fabrication of an optical device can be obtained within a short time period because fast homoeptaxia

Abstract: An n-doped, high quality gallium nitride substrate suitable for further device or epitaxial processing, and method for making the same. The nitride substrate is produced by epitaxial deposition of first metal nitride layer on a non-native substrate followed by a second deposition of metal nitride. During the second deposition of metal nitride, a liquid metal layer is formed at the interface of the non-native substrate and the metal nitride layer form. The formed metal nitride layer may be detached from the non-native substrate to provide an metal nitride substrate with a high quality inverse surface. A epitaxial metal nitride layer may be deposited on the inverse surface of metal nitride substrate. The metal nitride substrate and the epitaxial metal nitride layer thereon may be deposited using the same hydride vapor-phase epitaxy system.

Abstract: With an object of providing gallium nitride thick film crystals excelling in crystallization, the structure thereof is formed of an amorphous silicon dioxide thin film 2 formed on a silicon substrate 1 and then a single crystal silicon thin film 3 is formed on the foregoing amorphous silicon dioxide thin film 2 and further gallium nitride 4 is formed on this silicon thin film 3.

Abstract: A method of growing a nitride semiconductor crystal which has very few crystal defects and can be used as a substrate is disclosed. This invention includes the step of forming a first selective growth mask on a support member including a dissimilar substrate having a major surface and made of a material different from a nitride semiconductor, the first selective growth mask having a plurality of first windows for selectively exposing the upper surface of the support member, and the step of growing nitride semiconductor portions from the upper surface, of the support member, which is exposed from the windows, by using a gaseous Group 3 element source and a gaseous nitrogen source, until the nitride semiconductor portions grown in the adjacent windows combine with each other on the upper surface of the selective growth mask.

Abstract: A method for producing thick, high quality GaN substrates uses an epitaxially deposited film is used as a substrate material for further device or epitaxial processing. The film is deposited using an epitaxial technique on a thin substrate called the disposable substrate. The deposited film is thick enough so that upon cooling the thermal mismatched strain is relieved through cracking of the lower disposable substrate and not the newly deposited epitaxy. The epitaxial film now becomes a platform for either further epitaxial deposition or device processing.

Abstract: A method for forming a GaN-based semiconductor layer includes the steps of: forming a ZnO buffer layer on one of a glass substrate and a silicon substrate; and epitaxially growing a GaN-based semiconductor layer on the ZnO buffer layer by using an electron cyclotron resonance--molecular beam epitaxy (ECR-MBE) method.

Abstract: The present invention comprises growing gallium nitride films in the presence of bismuth using MBE at temperatures of about 1000 K or less. The present invention further comprises the gallium nitride films fabricated using the inventive fabrication method. The inventive films may be doped with magnesium or other dopants. The gallium nitride films were grown on sapphire substrates using a hollow anode Constricted Glow Discharge nitrogen plasma source. When bismuth was used as a surfactant, two-dimensional gallium nitride crystal sizes ranging between 10 .mu.m and 20 .mu.m were observed. This is 20 to 40 times larger than crystal sizes observed when GaN films were grown under similar circumstances but without bismuth. It is thought that the observed increase in crystal size is due bismuth inducing an increased surface diffusion coefficient for gallium. The calculated value of 4.7.times.10.sup.-7 cm.sup.2 /sec. reveals a virtual substrate temperature of 1258 K which is 260 degrees higher than the actual one.

Abstract: The method of forming gallium nitride crystal comprises the following three steps: the first step of heating a silicon substrate 1 in gas atmosphere including gallium, the second step of forming the first gallium nitride 3 on the silicon substrate 1, the third step of forming the second gallium nitride 4 on the first gallium nitride 3 at the higher temperature than when the first gallium nitride 3 has been formed. The method including these three steps can produce a thick film crystal of gallium nitride having excellent flatness and crystallinity.