C30B23/002

METHOD FOR MANUFACTURING SILICON CARBIDE SINGLE CRYSTAL

A method for manufacturing a SiC single crystal having a growth container surrounded by a heat-insulating material, a seed crystal substrate disposed inside a top at a center of the container, a silicon carbide raw material disposed at a bottom of the container to sublimate and grow a SiC crystal to allow a center of the hole to deviate from a center position of the seed substrate to a position on a periphery side, a SiC substrate having a main surface tilted from a {0001} plane wherein a basal plane is used and grown with the seed substrate so that a direction of a component of a normal vector of the basal plane of the seed substrate parallel to the main surface and an eccentric direction of the hole are opposite directions in a cross-sectional view including the center of the seed substrate and the center of the hole.

METHOD FOR PRODUCING P-TYPE 4H-SIC SINGLE CRYSTAL

A method for producing a p-type 4H-SiC single crystal includes sublimating a nitrided aluminum raw material and a SiC raw material. Further, there is a stacking of a SiC single crystal, which is co-doped with aluminum and nitrogen, on one surface of a seed crystal.

Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them

In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000 C., and cooling the bulk AlN crystal to a first temperature between approximately 1500 C. and approximately 1800 C. at a first rate less than approximately 250 C./hour.

CRYSTAL GROWING METHOD FOR CRYSTALS
20240011185 · 2024-01-11 · ·

A crystal growing method for crystals include the following steps. A first crystal seed is provided, the first crystal seed has a first monocrystalline proportion and a first size. N times of crystal growth processes are performed on the first crystal seed, wherein each of the crystal growth process will increase the monocrystalline proportion, and the N times of crystal growth processes are performed until a second crystal having a monocrystalline proportion of 100% is reached, and wherein the N times includes more than 3 times of crystal growth processes. Each crystal growth process includes adjusting a ratio difference (Tz/Tx) between an axial temperature gradient (Tz) and a radial temperature gradient (Tx) of the crystal, so as to control the ratio difference within a range of 0.5 to 3 for forming the second crystal.

CRYSTAL GROWTH METHOD AND WAFER

A crystal growth method, including providing a seed crystal in a crystal growth furnace, and forming a crystal on the seed crystal along a first direction after multiple time points, is provided. The crystal includes multiple sub-crystals stacked along the first direction, a corresponding one of the sub-crystals is formed at each of the time points, and the sub-crystals include multiple end surfaces away from the seed crystal, so that a difference value of maximum temperatures of any two of the end surfaces is less than or equal to 20 degrees. A wafer is also provided.

HIGHLY ORIENTED, SINGLE-CRYSTALLINE LOW-DIMENSIONAL NANOSTRUCTURES, METHOD OF FABRICATION AND DEVICES
20240011184 · 2024-01-11 ·

A method of fabricating low dimensional nanostructures on a growth substrate, a single-crystalline low dimensional nanostructure, and a device comprising one or more single-crystalline low dimensional nanostructures. The method comprises fabricating low dimensional nanostructures on a growth substrate using physical vapor deposition, PVD, in a vacuum chamber wherein the low dimensional nanostructures are formed as a strain relief mechanism promoted by a similarity of crystal structure 2-dimensional symmetry between the growth substrate and the low dimensional nanostructures to be grown and a lattice mismatch between the growth substrate and the low dimensional nanostructures to be grown.

Molecular beam epitaxy under vector strong magnetic field and in-situ characterization apparatus thereof

The present invention discloses a molecular beam epitaxy under vector strong magnetic field and an in-situ characterization apparatus thereof. The apparatus mainly consists of an inverted T-shaped ultrahigh vacuum growth and characterization chamber with a compact structure and a strong magnet. The inverted T-shaped vacuum chamber portion, which disposed in the room-temperature chamber of the strong magnet, includes a compact epitaxial growth sample stage, a device capable of rotating angle between the growth and magnetic field directions, and an in-situ characterization apparatus. The portion disposed below the strong magnet includes a molecular beam source component such as evaporation source, plasma source etc., and a vacuum-pumping system. The present invention surmounts effectively the technical problems between the small volume of the strong magnetic field chamber and numerous components of the growth and test system, and realizes the molecular beam epitaxial growth and in-situ characterization under the strong magnetic field.

THERMAL CONTROL FOR FORMATION AND PROCESSING OF ALUMINUM NITRIDE

In various embodiments, controlled heating and/or cooling conditions are utilized during the fabrication of aluminum nitride single crystals and aluminum nitride bulk polycrystalline ceramics. Thermal treatments may also be utilized to control properties of aluminum nitride crystals after fabrication.

METHOD OF ACQUIRING SAMPLE FOR EVALUATION OF SiC SINGLE CRYSTAL
20200182752 · 2020-06-11 · ·

A method of acquiring a sample for evaluation of a SiC single crystal, comprising: a step of cutting a SiC ingot in a radial direction at a thickness position, which is located in a range from a curved surface which forms a distal end surface in a crystal growth direction to a seed crystal, to obtain a head member which includes the curved surface, wherein the SiC ingot used in the step is a SiC ingot in which SiC thereof is crystal-grown from a seed crystal along a c axis direction; and a step of polishing a silicon surface of the head member to obtain a sample for evaluation.

SiC SINGLE CRYSTAL MANUFACTURING APPARATUS
20200080227 · 2020-03-12 · ·

The present invention provides a SiC single crystal manufacturing apparatus, including a crystal growth vessel which has a source loading portion to hold a SiC source, and a lid which is provided with a seed crystal support to hold a seed crystal; an insulating material which has at least one through-hole and covers the crystal growth vessel; a heater which is configured to heat the crystal growth vessel; and a temperature measuring instrument which is configured to measure the temperature of the crystal growth vessel through the through-hole, wherein the inner wall surface of the through-hole of the insulating material is coated with a coating material which contains a heat-resistant metal carbide or a heat-resistant metal nitride.