Abstract: A solid-state far ultraviolet light emitting element is formed by a hexagonal boron nitride single crystal, excited by electron beam irradiation to emit far ultraviolet light having a maximum light emission peak in a far ultraviolet region at a wavelength of 235 nm or shorter.

Abstract: The present III-nitride crystal manufacturing method, a method of manufacturing a III-nitride crystal (20) having a major surface (20m) of plane orientation other than {0001}, designated by choice, includes: a step of slicing III-nitride bulk crystal (1) into a plurality of III-nitride crystal substrates (10p), (10q) having major surfaces (10pm), (10qm) of the designated plane orientation; a step of disposing the substrates (10p), (10q) adjoining each other sideways in such a way that the major surfaces (10pm), (10qm) of the substrates (10p), (10q) parallel each other and so that the [0001] directions in the substrates (10p), (10q) are oriented in the same way; and a step of growing III-nitride crystal (20) onto the major surfaces (10pm), (10qm) of the substrates (10p), (10q).

Abstract: A method for producing a Group III nitride semiconductor crystal includes a first step of supplying a Group III raw material and a Group V raw material at a V/III ratio of 0 to 1,000 to form and grow a Group III nitride semiconductor on a heated substrate and a second step of vapor-phase-growing a Group III nitride semiconductor crystal on the substrate using a Group III raw material and a nitrogen raw material.

Abstract: A nitride semiconductor substrate and a method for manufacturing the same are provided. The nitride semiconductor substrate includes an epitaxy substrate, a nitride pillar layer, a nitride semiconductor layer, and a mask layer. The nitride pillar layer includes a plurality of first patterned arranged pillars and a plurality of second patterned arranged pillars. The nitride pillar layer is formed on the epitaxy substrate. A width of a cross-section of each of the second patterned arranged pillars is smaller than a width of a cross-section of each of the first patterned arranged pillars, and a distance among each of the second patterned arranged pillars is longer than a distance among each of the first patterned arranged pillars. Surfaces of the epitaxy substrate, the first patterned arranged pillars, and the second patterned arranged pillars are covered by the mask layer. The nitride semiconductor layer is formed on the nitride pillar layer.

Abstract: A method of evaluating damage of a compound semiconductor member, comprising: a step of performing measurement of photoluminescence on a surface of the compound semiconductor member; and a step of evaluating damage on the surface of the compound semiconductor member, using a half width of a peak at a wavelength corresponding to a bandgap of the compound semiconductor member, in an emission spectrum obtained by the measurement of photoluminescence.

Abstract: InyGa1-yN (0<y<1) layers whose principal surface is a non-polar plane or a semi-polar plane are formed by an MOCVD under different growth conditions. Then, the relationship between the growth temperature and the In supply mole fraction in a case where the pressure and the growth rate are constant is determined based on a growth condition employed for formation of InxGa1-xN (0<x<1) layers whose emission wavelengths are equal among the InyGa1-yN layers. Then, a saturation point is determined on a curve representing the relationship between the growth temperature and the In supply mole fraction, the saturation point being between a region where the growth temperature monotonically increases according to an increase of the In supply mole fraction and a region where the growth temperature saturates. Under a growth condition corresponding to this saturation point, an InxGa1-xN layer is grown.

Abstract: In a method of manufacturing an aluminum nitride single crystal film on a substrate by heating a sapphire substrate in the presence of carbon, nitrogen and carbon monoxide, an aluminum compound which differs from the raw material sapphire substrate and the formed aluminum nitride single crystal and can control the concentration of aluminum in the heating atmosphere, such as aluminum nitride or alumina, is made existent in a reaction system to promote a reduction nitriding reaction. An aluminum nitride single crystal multi-layer substrate having an aluminum nitride single crystal film on the surface of a sapphire substrate, wherein the aluminum nitride single crystal has improved crystallinity and a low density of defects, is provided.

Abstract: A Periodic Table Group 13 metal nitride crystal is grown by causing a reaction of a Periodic Table Group 13 metal phase with a nitride-containing molten salt phase to proceed while removing a by-product containing a metal element except for Periodic Table Group 13 metals, from the reaction field. According to this process, a high-quality Periodic Table Group 13 metal nitride bulk crystal can be produced under low pressure or atmospheric pressure.

Abstract: In the flux method, a source nitrogen gas is sufficiently heated before feeding to an Na—Ga mixture. The apparatus of the invention is provided for producing a group III nitride based compound semiconductor. The apparatus includes a reactor which maintains a group III metal and a metal differing from the group III metal in a molten state, a heating apparatus for heating the reactor, an outer vessel for accommodating the reactor and the heating apparatus, and a feed pipe for feeding a gas containing at least nitrogen from the outside of the outer vessel into the reactor. The feed pipe has a zone for being heated together with the reactor by means of the heating apparatus, wherein the zone is heated inside the outer vessel and outside the reactor.

Abstract: Isolation of III-nitride devices may be performed with a dopant selective etch that provides a smooth profile with little crystal damage in comparison to previously used isolation techniques. The dopant selective etch may be an electro-chemical or photo-electro-chemical etch. The desired isolation area may be identified by changing the conductivity type of the semiconductor material to be etched. The etch process can remove a conductive layer to isolate a device atop the conductive layer. The etch process can be self stopping, where the process automatically terminates when the selectively doped semiconductor material is removed.

Abstract: A method for growing flat, low defect density, and strain-free thick non-polar III-V nitride materials and devices on any suitable foreign substrates using a fabricated nano-pores and nano-network compliant layer with an HVPE, MOCVD, and integrated HVPE/MOCVD growth process in a manner that minimum growth will occur in the nano-pores is provided. The method produces nano-networks made of the non-polar III-V nitride material and the substrate used to grow it where the network is continuous along the surface of the template, and where the nano-pores can be of any shape.

Abstract: The substrate is used for opto-electric or electrical devices and comprises a layer of nitride grown by means of vapor phase epitaxy growth wherein both main surfaces of the nitride substrate are substantially consisting of non N-polar face and N-polar face respectively and the dislocation density of the substrate is 5×105/cm2 or less. Therefore, the template type substrate has a good dislocation density and a good value of FWHM of the X-ray rocking curve from (0002) plane less than 80, so that the resulting template type substrate is very useful for the epitaxy substrate from gaseous phase such as MOCVD, MBE and HVPE, resulting in possibility of making good opto-electric devices such as Laser Diode and large-output LED and good electric devices such as MOSFET.

Abstract: Method for producing a III-N (AlN, GaN, AlxGa(1-x)N) crystal by Vapor Phase Epitaxy (VPE), the method comprising: providing a reactor having: a growth zone for growing a III-N crystal; a substrate holder located in the growth zone that supports at least one substrate on which to grow the III-N crystal; a gas supply system that delivers growth material for growing the III-N crystal to the growth zone from an outlet of the gas supply system; and a heating element that controls temperature in the reactor; determining three growth sub-zones in the growth zone for which a crystal grown in the growth sub-zones has respectively a concave, flat or convex curvature; growing the III-N crystal on a substrate in a growth region for which the crystal has a by desired curvature.

Abstract: Bulk GaN and AlGaN single crystal boules, preferably fabricated using a modified HVPE process, are provided. The single crystal boules typically have a volume in excess of 4 cubic centimeters with a minimum dimension of approximately 1 centimeter. If desired, the bulk material can be doped during growth, for example to achieve n-, i-, or p-type conductivity.

Abstract: Fabrication of doped and undoped stoichiometric polycrystalline AlN ceramics with high purity is accomplished by, for example, reacting Al pellets with nitrogen gas. Such polycrystalline AlN ceramics may be utilized in the fabrication of high purity AlN single crystals, which may be annealed to enhance a conductivity thereof.

Abstract: Affords a Group-III nitride crystal substrate that is of low dislocation density and is inexpensive to manufacture, a method of manufacturing such a substrate, and Group-III nitride semiconductor devices that incorporate the Group-III nitride crystal substrate. The Group-III nitride crystal substrate manufacturing method includes: a step of growing, by liquid-phase epitaxy, a first Group-III nitride crystal (2) onto a base substrate (1); and a step of growing, by vapor-phase epitaxy, a second Group-III nitride crystal (3) onto the first Group-III nitride crystal (2). The Group-III nitride crystal substrate, produced by such a manufacturing method, has a dislocation density of 1×107 dislocations/cm2.

Abstract: It is used a substrate main body 1 having a side face 1b and a pair of main faces 1a and an underlying film 2 of a single crystal of a nitride of a metal belonging to the group III formed at least on one main face of the substrate main body 1. A single crystal 3 of a nitride of a metal belonging to the group III is grown on the main face 1a of the substrate main body 1 by a liquid phase process. The underlying film 2 has a shape of a convex figure in a plan view. A surface 4 without the underlying film thereon surrounds the entire circumference of the underlying film 2. The single crystal 3 of a nitride of a metal belonging to the group III grown on the underlying film 2 is not brought into contact with a single crystal of a nitride of a metal belonging to group III formed on another underlying film.

Abstract: Large area single crystal III-V nitride material having an area of at least 2 cm2, having a uniformly low dislocation density not exceeding 3×106 dislocations per cm2 of growth surface area, and including a plurality of distinct regions having elevated impurity concentration, wherein each distinct region has at least one dimension greater than 50 microns, is disclosed. Such material can be formed on a substrate by a process including (i) a first phase of growing the III-V nitride material on the substrate under pitted growth conditions, e.g., forming pits over at least 50% of the growth surface of the III-V nitride material, wherein the pit density on the growth surface is at least 102 pits/cm2 of the growth surface, and (ii) a second phase of growing the III-V nitride material under pit-filling conditions.

Abstract: Reconditioned donor substrates that include a remainder substrate from a donor substrate wherein the remainder substrate has a detachment surface where a transfer layer was detached and an opposite surface; and an additional layer deposited upon the opposite surface of the remainder substrate to increase its thickness and to form the reconditioned substrate. The reconditioned substrate is recycled as a donor substrate for fabricating compound material wafers and is typically made from gallium nitride donor substrates.

Abstract: A production method is provided in which Group-III-element nitride single crystals that have a lower dislocation density and a uniform thickness and are transparent, high quality, large, and bulk crystals can be produced with a high yield. The method for producing Group-III-element nitride single crystals includes: heating a reaction vessel containing at least one metal element selected from the group consisting of an alkali metal and an alkaline-earth metal and at least one Group III element selected from the group consisting of gallium (Ga), aluminum (Al), and indium (In) to prepare a flux of the metal element; and feeding nitrogen-containing gas into the reaction vessel and thereby allowing the Group III element and nitrogen to react with each other in the flux to grow Group-III-element nitride single crystals, wherein the single crystals are grown, with the flux being stirred by rocking the reaction vessel, for instance.

Abstract: The object of this invention is to provide a high-output type nitride light emitting device. The nitride light emitting device comprises an n-type nitride semiconductor layer or layers, a p-type nitride semiconductor layer or layers and an active layer therebetween, wherein a gallium-containing nitride substrate is obtained from a gallium-containing nitride bulk single crystal, provided with an epitaxial growth face with dislocation density of 105/cm2 or less, and A-plane or M-plane which is parallel to C-axis of hexagonal structure for an epitaxial face, wherein the n-type semiconductor layer or layers are formed directly on the A-plane or M-plane. In case that the active layer comprises a nitride semiconductor containing In, an end face film of single crystal AlxGa1-xN (0?x?1) can be formed at a low temperature not causing damage to the active layer.

Abstract: A method of making a metal nitride is provided. The method may include introducing a metal in a chamber. A nitrogen-containing material may be flowed into the chamber. Further, a hydrogen halide may be introduced. The nitrogen-containing material may react with the metal in the chamber to form the metal nitride.

Abstract: A boule formed by high rate vapor phase growth of Group III-V nitride boules (ingots) on native nitride seeds, from which wafers may be derived for fabrication of microelectronic device structures. The boule is of microelectronic device quality, e.g., having a transverse dimension greater than 1 centimeter, a length greater than 1 millimeter, and a top surface defect density of less than 107 defects cm?2. The Group III-V nitride boule may be formed by growing a Group III-V nitride material on a corresponding native Group III-V nitride seed crystal by vapor phase epitaxy at a growth rate above 20 micrometers per hour. Nuclear transmutation doping may be applied to an (Al,Ga,In)N article comprises a boule, wafer, or epitaxial layer.

Abstract: A synthesis route to grow textured thin film of gallium nitride on amorphous quartz substrates and on single crystalline substrates such as c-sapphire and polycrystalline substrates such as pyrolytic boron nitride (PBN), alumina and quartz using the dissolution of atomic nitrogen rather than molecular nitrogen to allow for growth at subatmospheric pressure.

Abstract: Methods of controlling stress in GaN films deposited on silicon and silicon carbide substrates and the films produced therefrom are disclosed. A typical method comprises providing a substrate and depositing a graded gallium nitride layer on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. A typical semiconductor film comprises a substrate and a graded gallium nitride layer deposited on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply.

Abstract: A method of growing hexagonal boron nitride single crystal is provided. Hexagonal boron nitride single crystal is grown in calcium nitride flux by heating, or heating and then slowly cooling, boron nitride and a calcium series material in an atmosphere containing nitrogen. Bulk hexagonal boron nitride single crystal can thereby successfully be grown.

Abstract: A process for obtaining bulk mono-crystalline gallium-containing nitride, liminating impurities from the obtained crystal and manufacturing substrates made of bulk mono-crystalline gallium-containing nitride has been now proposed.

Abstract: A method for producing Group-III-element nitride crystals by which an improved growth rate is obtained and large high-quality crystals can be grown in a short time, a producing apparatus used therein, and a semiconductor element obtained using the method and the apparatus are provided. The method is a method for producing Group-III-element nitride crystals that includes a crystal growth process of subjecting a material solution containing a Group III element, nitrogen, and at least one of alkali metal and alkaline-earth metal to pressurizing and heating under an atmosphere of a nitrogen-containing gas so that the nitrogen and the Group III element in the material solution react with each other to grow crystals.

Abstract: Disclosed is a method of manufacturing a GaN-based material having high thermal conductivity. A gallium nitride-based material is grown by HVPE (Hydride Vapor Phase Epitaxial Growth) by supplying a carrier gas (G1) containing H2 gas, GaCl gas (G2), and NH3 gas (G3) to a reaction chamber (10), and setting the growth temperature at 900 (° C.) (inclusive) to 1,200 (° C.) (inclusive), the growth pressure at 8.08×104 (Pa) (inclusive) to 1.21×105 (Pa) (inclusive), the partial pressure of the GaCl gas (G2) at 1.0×104 (Pa) (inclusive) to 1.0×104 (Pa) (inclusive), and the partial pressure of the NH3 gas (G3) at 9.1×102 (Pa) (inclusive) to 2.0×104 (Pa) (inclusive).

Abstract: A single crystal M*N article, which may be made by a process including the steps of: providing a substrate of material having a crystalline surface which is epitaxially compatible with M*N; depositing a layer of single crystal M*N over the surface of the substrate; and removing the substrate from the layer of single crystal M*N, e.g., with an etching agent which is applied to the substrate to remove same, to yield the layer of single crystal M*N as said single crystal M*N article. The bulk single crystal M*N article is suitable for use as a substrate for the fabrication of microelectronic structures thereon, to produce microelectronic devices comprising bulk single crystal M*N substrates, or precursor structures thereof.

Abstract: A method of producing a separated GaN crystal body grown by vapor phase epitaxy on a substrate made of material different from GaN is provided. In this method, a nitride deposit is formed during the growth on a periphery of the substrate and GaN crystal body. The present method comprises the steps of: processing the periphery of the substrate to remove the nitride deposit; and, after the peripheral processing, separating the substrate from the GaN crystal body to make the substrate and the GaN crystal body independent of each other.

Abstract: A method for forming vertically oriented, crystallographically aligned nanowires (nanocolumns) using monolayer or submonolayer quantities of metal atoms to form uniformly sized metal islands that serve as catalysts for MOCVD growth of Group III nitride nanowires.

Abstract: An object of the invention is to carry out the flux method with improved work efficiency while maintaining the purity of flux at high level and saving flux material cost. The sodium-purifying apparatus includes a sodium-holding-and-management apparatus for maintaining purified sodium (Na) in a liquid state. Liquid sodium is supplied into a sodium-holding-and-management apparatus through a liquid-sodium supply piping maintained at 100° C. to 200° C. The sodium-holding-and-management apparatus further has an argon-gas-purifying apparatus for controlling the condition of argon (Ar) gas that fills the internal space thereof. Thus, by opening and closing a faucet at desired timing, purified liquid sodium (Na) supplied from the sodium-purifying apparatus can be introduced into a crucible as appropriate via the liquid-sodium supply piping, the sodium-holding-and-management apparatus, and the piping.

Abstract: A method of making a group III nitride-based compound semiconductor has the steps of: providing a semiconductor substrate with a polished surface, the semiconductor substrate being of group III nitride-based compound semiconductor; and growing a semiconductor epitaxial growth layer of group III nitride-based compound semiconductor on the semiconductor substrate. The polished surface is an inclined surface that has an off-angle ? of 0.15 degrees or more and 0.6 degrees or less to a-face, c-face or m-face of the semiconductor substrate.

Abstract: Methods of controlling stress in GaN films deposited on silicon and silicon carbide substrates and the films produced therefrom are disclosed. A typical method comprises providing a substrate and depositing a graded gallium nitride layer on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. A typical semiconductor film comprises a substrate and a graded gallium nitride layer deposited on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply.

Abstract: There is disclosed a PBN container in which a conductive film is deposited on a surface of a body formed by depositing PBN (pyrolytic boron nitride), wherein, at least, an angle between a PBN cut face of the body and at least one wall surface adjacent to the PBN cut face is 20°-80°, and a method for producing a PBN (pyrolytic boron nitride) container comprising at least steps of depositing PBN to form a body, processing a PBN cut face of the formed body so that at least, an angle between the PBN cut face and at least one wall surface adjacent to the PBN cut face is 20°-80°, and coating a surface of the processed body with a conductive film. Thus, there can be provided a PBN container excellent in durability where a conductive film is laminated on a surface of a body formed by depositing PBN, and a method for producing the PBN container.

Abstract: A method of growing bulk single crystals of an AlN on a single crystal seed is provided, wherein an AlN source material is placed within a crucible chamber in spacial relationship to a seed fused to the cap of the crucible. The crucible is heated in a manner sufficient to establish a temperature gradient between the source material and the seed with the seed at a higher temperature than the source material such that the outer layer of the seed is evaporated, thereby cleaning the seed of contaminants and removing any damage to the seed incurred during seed preparation. Thereafter, the temperature gradient between the source material and the seed is inverted so that the source material is sublimed and deposited on the seed, thereby growing a bulk single crystal of AlN.

Abstract: It is provided a method for gently and safely recovering only sodium metal from a flux containing sodium metal in a short time and in a reusable form. Flux 23 is heated in a medium 19 unreactive with sodium metal 22 at a temperature equal to or higher than the melting point of sodium metal to separate and recover the sodium metal 22 from the flux 23. The medium is a hydrocarbon, for example.

Abstract: A method for growing high quality, nonpolar Group III nitrides using lateral growth from Group III nitride nanowires. The method of nanowire-templated lateral epitaxial growth (NTLEG) employs crystallographically aligned, substantially vertical Group III nitride nanowire arrays grown by metal-catalyzed metal-organic chemical vapor deposition (MOCVD) as templates for the lateral growth and coalescence of virtually crack-free Group III nitride films. This method requires no patterning or separate nitride growth step.

Abstract: A nitride-based semiconductor substrate having a diameter of 25 mm or more, a thickness of 250 micrometers or more, and an optical absorption coefficient of less than 7 cm?1 to light with a wavelength of 380 nm or more. The nitride-based semiconductor substrate is made by the HVPE method that uses gallium chloride obtained by reacting a Ga melt with a hydrogen chloride gas. The Ga melt is contacted with the hydrogen chloride gas for one minute or more to produce the gallium chloride.

Abstract: A boule formed by high rate vapor phase growth of Group III-V nitride boules (ingots) on native nitride seeds, from which wafers may be derived for fabrication of microelectronic device structures. The boule is of microelectronic device quality, e.g., having a transverse dimension greater than 1 centimeter, a length greater than 1 millimeter, and a top surface defect density of less than 107 defects cm?2. The Group III-V nitride boule may be formed by growing a Group III-V nitride material on a corresponding native Group III-V nitride seed crystal by vapor phase epitaxy at a growth rate above 20 micrometers per hour.

Abstract: Methods of controlling stress in GaN films deposited on silicon and silicon carbide substrates and the films produced therefrom are disclosed. A typical method comprises providing a substrate and depositing a graded gallium nitride layer on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. A typical semiconductor film comprises a substrate and a graded gallium nitride layer deposited on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply.

Abstract: A method of growing a p-type nitride semiconductor material by molecular beam epitaxy (MBE) uses bis(cyclopentadienyl)magnesium (Cp2Mg) as the source of magnesium dopant atoms. Ammonia gas is used as the nitrogen precursor for the MBE growth process. To grow p-type GaN, for example, by the method of the invention, gallium, ammonia and Cp2Mg are supplied to an MBE growth chamber; to grow p-type AlGaN, aluminum is additionally supplied to the growth chamber. The growth process of the invention produces a p-type carrier concentration, as measured by room temperature Hall effect measurements, of up to 2 1017 cm?3, without the need for any post-growth step of activating the dopant atoms.

Abstract: A method for growing a crystal of an Al-containing III-V group compound semiconductor by the conventional HVPE method, characterized in that it comprises a step of reacting Al with hydrogen halide at a temperature of 700° C. or lower to form a halide of Al. The method has allowed the suppression of the formation of aluminum chloride (AlCl) or aluminum bromide (AlBr) reacting violently with quartz, which is the material of a reaction vessel for the growth, resulting in the achievement of the vapor phase growth of an Al-containing III-V group compound semiconductor at a rate of 100 microns/hr or more, which has lead to the mass-production of a substrate and a semiconductor element having satisfactory resistance to adverse environment.

Abstract: A self-supported nitride semiconductor substrate of 10 mm or more in diameter having an X-ray diffraction half width of 500 seconds or less in at least one of a {20-24} diffraction plane and a {11-24} diffraction plane.

Abstract: SiC is a very stable substance, and it is difficult to control the condition of a SiC surface to be suitable for crystal growth in conventional Group III nitride crystal growing apparatuses. This problem is solved as follows. The surface of a SiC substrate 1 is rendered into a step-terrace structure by performing a heating process in an atmosphere of HCl gas. The surface of the SiC substrate 1 is then treated sequentially with aqua regia, hydrochloric acid, and hydrofluoric acid. A small amount of silicon oxide film formed on the surface of the SiC substrate 1 is etched so as to form a clean SiC surface 3 on the substrate surface. The SiC substrate 1 is then installed in a high-vacuum apparatus and the pressure inside is maintained at ultrahigh vacuum (such as 10?6 to 10?8 Pa). In the ultrahigh vacuum state, a process of irradiating the surface with a Ga atomic beam 5 at time t1 at temperature of 800° C. or lower and performing a heating treatment at 800° C. or higher is repeated at least once.

Abstract: The present invention relates to a fabrication method of gallium manganese nitride (GaMnN) single crystal nanowire, more particularly to a fabrication method of GaMnN single crystal nanowire substrate by halide vapor phase epitaxy (HVPE) in which such metal components as gallium (Ga) and manganese (Mn) react with such gas components as nitrogen (N2), hydrogen chloride (HCl) and ammonia (NH3), wherein the amount of the gas components are adjusted to control the Mn doping concentration in order to obtain nanowire having a perfect, one-dimensional, single crystal structure without internal defect, concentration of holes, or carriers, and magnetization value of which being determined by the doping concentration and showing ferromagnetism at room temperature, thus being a useful spin transporter in the field of the next-generation spintronics, such as spin-polarized LED, spin-polarized FET, etc.

Abstract: A method for growing bulk GaN and AlGaN single crystal boules, preferably using a modified HVPE process, is provided. The single crystal boules typically have a volume in excess of 4 cubic centimeters with a minimum dimension of approximately 1 centimeter. If desired, the bulk material can be doped during growth to achieve n-, i-, or p-type conductivity. In order to have growth cycles of sufficient duration, preferably an extended Ga source is used in which a portion of the Ga source is maintained at a relatively high temperature while most of the Ga source is maintained at a temperature close to, and just above, the melting temperature of Ga. To grow large boules of AlGaN, preferably multiple Al sources are used, the Al sources being sequentially activated to avoid Al source depletion and excessive degradation.

Abstract: Methods of crystal growth for semiconductor materials, such as nitride semiconductors, and methods of manufacturing semiconductor devices are provided. The method of crystal growth includes forming a number of island crystal regions during a first crystal growth phase and continuing growth of the island crystal regions during a second crystal growth phase while bonding of boundaries of the island crystal regions occurs. The second crystal growth phase can include a crystal growth rate that is higher than the crystal growth rate of the first crystal growth phase and/or a temperature that is lower than the first crystal growth phase. This can reduce the density of dislocations, thereby improving the performance and service life of a semiconductor device which is formed on a nitride semiconductor made in accordance with an embodiment of the present invention.

Abstract: An aerosol of a powder composed of helium carrier gas and particles of a hexagonal aluminum nitride is charged through a transfer pipe 3 into a film deposition chamber 4 whose interior is depressurized by gas evacuation using a vacuum pump 5 to maintain a degree of vacuum of 200-8000 Pa during supply of the carrier gas and the aerosol is blown from a nozzle 6 provided on the end of the transfer pipe 3 inside the film deposition chamber 4 to impinge on a substrate fastened to a substrate holder 7 to make the impact force of the particles at collision with the substrate 4 GPa or greater, thereby transforming the crystal structure of the aluminum nitride from hexagonal to cubic to deposit cubic aluminum nitride on the substrate.