A group III nitride single crystal substrate comprises: a first main face; and a first back face opposite to the first main face, wherein an absolute value of a radius of curvature of the first main face of the substrate is 10 m or more; an absolute value of a radius of curvature of a crystal lattice plane at a center of the first main face of the substrate is 10 m or more; and a 1/1000 intensity width of an X-ray rocking curve of a low-incidence-angle face at the center of the first main face of the substrate is 1200 arcsec or less.

A method for manufacturing a semiconductor element includes providing, on a surface of a substrate 11, a mask 12 which has an opening 12a and in which a peripheral upper surface region of the opening is processed to have a predetermined structure, and epitaxially growing a semiconductor from the surface of the substrate exposed from the opening to the top of the peripheral upper surface region to fabricate a semiconductor element having a semiconductor layer 13 with the predetermined structure transferred thereon. In one example, the predetermined structure is due to a shape having a difference in level. In another example, the predetermined structure is due to a selectively arranged element, and the transferred element moves into the semiconductor layer.

A method for manufacturing a vertical JFET includes providing a III-nitride substrate having a first conductivity type; forming a first III-nitride layer coupled to the III-nitride substrate, wherein the first III-nitride layer is characterized by a first dopant concentration and the first conductivity type; forming a plurality of trenches within the first III-nitride layer, wherein the plurality of trenches extend to a predetermined depth; epitaxially regrowing a second III-nitride structure in the trenches, wherein the second III-nitride structure is characterized by a second conductivity type; forming a plurality of III-nitride fins, each coupled to the first III-nitride layer, wherein the plurality of III-nitride fins are separated by one of a plurality of recess regions; epitaxially regrowing a III-nitride gate layer in the recess regions, wherein the III-nitride gate layer is coupled to the second III-nitride structure, and wherein the III-nitride gate layer is characterized by the second conductivity type.

In certain examples, methods and semiconductor structures are directed to a method comprising steps of forming by monolithically integrating or seeding via polycrystalline diamond (PCD) particles on a GaN-based layer characterized as including GaN in at least a surface region of the GaN-based layer. After the step of seeding, the PCD particles are grown under a selected pressure to form a diamond layer section and to provide a semi-conductive structure that includes the diamond layer section integrated on or against the surface region of the GaN-based layer.

A III-nitride-based semiconductor packaged structure includes a lead frame, an adhesive layer, a III-nitride-based die, an encapsulant, and at least one bonding wire. The lead frame includes a die paddle and a lead. The die paddle has first and second recesses arranged in a top surface of the die paddle. The first recesses are located adjacent to a relatively central region of the top surface. The second recesses are located adjacent to a relatively peripheral region of the top surface. The first recess has a shape different from the second recess from a top-view perspective. The adhesive layer is disposed on the die paddle to fill into the first recesses. The III-nitride-based die is disposed on the adhesive layer. The encapsulant encapsulates the lead frame and the III-nitride-based die. The second recesses are filled with the encapsulant. The bonding wire is encapsulated by the encapsulant.

A method of performing heteroepitaxy comprises exposing a substrate to a carrier gas, a first precursor gas, a Group II/III element, and a second precursor gas, to form a heteroepitaxial growth of one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN on the substrate; wherein the substrate comprises one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN; wherein the carrier gas is Hz, wherein the first precursor is HCl, the Group II/III element comprises at least one of Zn, Cd, Hg, Al, Ga, and In; and wherein the second precursor is one of AsH.sub.3 (arsine), PH.sub.3 (phosphine), H.sub.2Se (hydrogen selenide), H.sub.2Te (hydrogen telluride), SbH.sub.3 (hydrogen antimonide), H.sub.2S (hydrogen sulfide), and NH.sub.3 (ammonia). The process may be an HVPE (hydride vapor phase epitaxy) process.

A method of removing a substrate, comprising: forming a growth restrict mask with a plurality of striped opening areas directly or indirectly upon a GaN-based substrate; and growing a plurality of semiconductor layers upon the GaN-based substrate using the growth restrict mask, such that the growth extends in a direction parallel to the striped opening areas of the growth restrict mask, and growth is stopped before the semiconductor layers coalesce, thereby resulting in island-like semiconductor layers. A device is processed for each of the island-like semiconductor layers. Etching is performed until at least a part of the growth restrict mask is exposed. The devices are then bonded to a support substrate. The GaN-based substrate is removed from the devices by a wet etching technique that at least partially dissolves the growth restrict mask. The GaN substrate that is removed then can be recycled.

A semiconductor chip includes a chip constituent substrate having a first surface and a second surface, and including a layer containing gallium nitride. The chip constituent substrate is provided with a semiconductor element, and components constituting the semiconductor element are located more in an area adjacent to the first surface than in an area adjacent to the second surface. The chip constituent substrate is formed with a through hole penetrating the chip constituent substrate from the first surface to the second surface. The through hole defines a first opening adjacent to the first surface and a second opening adjacent to the second surface, and the first opening is larger than the second opening.

A method of manufacturing nitride semiconductor substrate, comprising: providing silicon-on-insulator substrate which comprises an underlying silicon layer, a buried silicon dioxide layer and a top silicon layer; forming a first nitride semiconductor layer on the top silicon layer; forming, in the first nitride semiconductor layer, a plurality of notches which expose the top silicon layer; removing the top silicon layer and forming a plurality of protrusions and a plurality of recesses on an upper surface of the buried silicon dioxide layer, wherein each of the plurality of protrusions is in contact with the first nitride semiconductor layer, and there is a gap between each of the plurality of recesses and the first nitride semiconductor layer; and epitaxially growing a second nitride semiconductor layer on the first nitride semiconductor layer, such that the first nitride semiconductor layer and the second nitride semiconductor layer form a nitride semiconductor substrate.

An epitaxial lateral overgrowth (ELO) of a III-nitride layer is used to cover a growth restrict mask deposited on a substrate, wherein the III-nitride ELO layer is grown with a low V/III ratio of less than 500 resulting in high-speed lateral growth as compared to low-speed vertical growth. The III-nitride ELO layer contains a large amount of impurities, over 1 × 10.sup.18 cm.sup.-3, which result in the III-nitride ELO layer comprising a coloring layer. The coloring layer absorbs light from an active region due to the large amount of impurities. When a bar of device layers is removed from the substrate, at least a portion of the coloring layer is removed from the bar. The elimination of the coloring layer reduces absorption losses, which makes the device characteristics improve.