A method for manufacturing a group III nitride substrate is described. The method involves forming group III nitride films having a group III element face on a surface thereof, on both surfaces of a substrate, so as to produce a group III nitride film carrier. The group III nitride film carrier is subjected to ion implantation and adhered to a base substrate containing polycrystals containing a group III nitride as a major component. The group III nitride film carrier is spaced from the base substrate to transfer the ion-implanted region to the base substrate, so as to form a group III nitride film having an N face on a surface thereof on the base substrate. A group III nitride film is formed on the group III nitride by a THVPE method, so as to produce a thick film of a group III nitride film.

Core-cladding planar waveguide (PWG) structures and methods of making and using same. The core-cladding PWG structures can be synthesized by hydride vapor phase epitaxy and processed by mechanical and chemical-mechanical polishing. An Er doping concentration of [Er] between 1×10.sup.18 atoms/cm.sup.3 and 1×10.sup.22 atoms/cm.sup.3 can be in the core layer. Such PWGs have a core region that can achieve optical confinement between 96% and 99% and above.

There is provided a Group-III element nitride semiconductor substrate including a first surface and a second surface, in which even when devices to be produced on the first surface are increased in size, variations in device characteristics between the devices in the same substrate are suppressed. A Group-III element nitride semiconductor substrate includes a first surface and a second surface. The Group-III element nitride semiconductor substrate satisfies at least one of the following items (1) to (3): (1) The main surface has a maximum height Wz of a surface waviness profile of 150 nm or less; (2) The main surface has a root mean square height Wq of the surface waviness profile of 25 nm or less; (3) The main surface has an average length WSm of surface waviness profile elements of 0.5 mm or more.

A method for manufacturing a semiconductor structure is provided. The method includes a III-V semiconductor device in a first region of a base substrate and a further device in a second region of the base substrate. The method includes: (a) obtaining a base substrate comprising the first region and the second region, different from the first region; (b) providing a buffer layer over a surface of the base substrate at least in the first region, wherein the buffer layer comprises at least one monolayer of a first two-dimensional layered crystal material; (c) forming, over the buffer layer in the first region, and not in the second region, a III-V semiconductor material; and (d) forming, in the second region, at least part of the further device. A semiconductor structure is also provided.

This disclosure relates to methods of growing crystalline layers on amorphous substrates by way of an ultra-thin seed layer, methods for preparing the seed layer, and compositions comprising both. In an aspect of the invention, the crystalline layers can be thin films. In a preferred embodiment, these thin films can be free-standing.

The present invention relates to a method for reducing lateral growth as well as growth of the bottom surface of crystals in a crystal growing process, wherein before the crystal seed undergoes a growing process the method includes a step of wrapping the crystal seed with metal foil so that all the side surfaces as well as the bottom surface of the crystal seed are surrounded by the foil.

A manufacturing apparatus for a group-III nitride crystal, the manufacturing apparatus includes: a raw material chamber that produces therein a group-III element oxide gas; and a nurturing chamber in which a group-III element oxide gas supplied from the raw material chamber and a nitrogen element-containing gas react therein to produce a group-III nitride crystal on a seed substrate, wherein an angle that is formed by a direction along a shortest distance between a forward end of a group-III element oxide gas supply inlet to supply the group-III element oxide gas into the nurturing chamber and an outer circumference of the seed substrate placed in the nurturing chamber, and a surface of the seed substrate is denoted by “θ”, wherein a diameter of the group-Ill element oxide gas supply inlet is denoted by “S”, wherein a distance between a surface, on which the seed substrate is placed, of a substrate susceptor that holds the seed substrate and a forward end of a first carrier gas supply inlet to supply a first carrier gas into the nurturing chamber is denoted by “L.sub.1”, wherein a distance between the forward end of the first carrier gas supply inlet and the forward end of the group-III element oxide gas supply inlet is denoted by “M.sub.1”, wherein a diameter of the seed substrate is denoted by “k”, and wherein following Eqs. (1) to (4), 0°<θ<90° (1), 0.21≤S/k≤0.35 (2), 1.17≤(L.sub.1+M.sub.1)/k≤1.55 (3), k=2*(L.sub.1+M.sub.1)/tan θ+S (4) are satisfied.

A manufacturing method for a group-III nitride crystal, the manufacturing method includes: preparing a seed substrate; increasing temperature of the seed substrate placed in a nurturing chamber; and supplying a group-III element oxide gas produced in a raw material chamber connected to the nurturing chamber by a connecting pipe and a nitrogen element-containing gas into the nurturing chamber to grow a group-III nitride crystal on the seed substrate, wherein a flow amount y of a carrier gas supplied into the raw material chamber at the temperature increase step satisfies following two relational equations (I) and (II), y<[1−k*H(Ts)]/[k*H(Ts)−j*H(Tg)]j*H(Tg)*t (I), y≥1.58*10.sup.−4*(22.4/28)S*F(N)/F(T) (II), wherein k represents an arrival rate to a saturated vapor pressure of a group-III element in the raw material chamber, Ts represents a temperature of the raw material chamber, Tg represents a temperature of the nurturing chamber, H(Ts) represents a saturated vapor pressure of the group-III element at the temperature Ts in the raw material chamber, H(Tg) represents a saturated vapor pressure of the group-III element at the temperature Tg in the nurturing chamber, j represents a corrective coefficient, t represents a sum of gas flow amounts flowing into the nurturing chamber from those other than the raw material chamber, S represents a cross-sectional area of the connecting pipe, F(N) represents a volumetric flow amount of the nitrogen element-containing gas supplied into the nurturing chamber, and F(T) represents a sum of volumetric flow amounts of gases supplied into the nurturing chamber from those other than the raw material chamber.

A manufacturing method of a nitride semiconductor device includes: introducing a p type impurity into at least a part of an upper layer portion of a first nitride semiconductor layer to form a p type impurity introduction region; forming a second nitride semiconductor layer from an upper surface of the first nitride semiconductor layer so as to include the p type impurity introduction region; and performing an anneal treatment in a state where the second nitride semiconductor layer is formed on the first nitride semiconductor layer.

The manufacturing apparatus for a group-III compound semiconductor crystal according to the present disclosure comprises a reaction container. The reaction container has a raw material reaction section, a crystal growth section, and a gas flow channel. The raw material reaction section has a raw material reaction chamber, and a raw material gas nozzle. The crystal growth section has a substrate supporting member, and reactive gas nozzles. The gas flow channel includes a first flow channel, a second flow channel, and a connection portion. The first flow channel has a first opening, and the second flow channel has a second opening. The area of the second opening is configured to be larger than the area of the first opening. The connection portion connects the first opening and the second opening with each other. The gas flow channel forms a gas flow path in the reaction container. The substrate supporting member is disposed inside the gas flow path and located on the downstream side of the first opening.