Patent classifications
C30B25/183
METHOD FOR GROWING A NON-POLAR A-PLANE GALLIUM NITRIDE USING ALUMINUM NITRIDE / GALLIUM NITRIDE SUPERLATTICES
A method for growing a non-polar a-plane gallium nitride includes cleaning of r-sapphire substrate, and nitridating for initiating growth sequences. The growth sequences include growing a gallium nitride nucleation layer, growing a thick first layer of gallium nitride, growing a film stack of gallium nitride and aluminum nitride as a superlattices layer, and overgrowing of gallium nitride on superlattices layer to form a second layer. The non-polar a-plane gallium nitride is grown by inserting multiple layers of a gallium nitride and an aluminum nitride for improving lateral surface morphology of gallium nitride on r-sapphire substrate.
Optimized heteroepitaxial growth of semiconductors
A method of performing HVPE heteroepitaxy comprises exposing a substrate to a carrier gas, a first precursor gas, a Group II/III element, and ternary-forming gasses (V/VI group precursor), to form a heteroepitaxial growth of a binary, ternary, and/or quaternary compound on the substrate; wherein the carrier gas is H.sub.2, wherein the first precursor gas is HCl, the Group II/III element comprises at least one of Zn, Cd, Hg, Al, Ga, and In; and wherein the ternary-forming gasses comprise at least two or more of AsH.sub.3 (arsine), PH.sub.3 (phosphine), H.sub.2Se (hydrogen selenide), H.sub.2Te (hydrogen telluride), SbH.sub.3 (hydrogen antimonide, or antimony tri-hydride, or stibine), H.sub.2S (hydrogen sulfide), NH.sub.3 (ammonia), and HF (hydrogen fluoride); flowing the carrier gas over the Group II/III element; exposing the substrate to the ternary-forming gasses in a predetermined ratio of first ternary-forming gas to second ternary-forming gas (1tf:2tf ratio); and changing the 1tf:2tf ratio over time.
Foundation substrate for producing diamond film and method for producing diamond substrate using same
It is an object to provide a method for producing a diamond substrate effective for reducing various defects including dislocation defects and a foundation substrate used for the same. This object is achieved by a foundation substrate for forming a diamond film by a chemical vapor deposition method, wherein an off angle is provided to the surface of the foundation substrate with respect to a predetermined crystal plane orientation.
INTEGRATED CIRCUIT DEVICES WITH AN ENGINEERED SUBSTRATE
An integrated circuit device includes an engineered substrate including a substantially single crystal layer and a buffer layer coupled to the substantially single crystal layer. The integrated circuit device also includes a plurality of semiconductor devices coupled to the buffer layer. The plurality of semiconductor devices can include a first power device coupled to a first portion of the buffer layer and a second power device coupled to a second portion of the buffer layer. The first power device includes a first channel region comprising a first end, a second end, and a first central portion disposed between the first end and the second end. The second power device includes a second channel region comprising a third end, a fourth end, and a second central portion disposed between the third end and the fourth end.
METHOD FOR MANUFACTURING EPITAXIAL WAFER, SILICON-BASED SUBSTRATE FOR EPITAXIAL GROWTH, AND EPITAXIAL WAFER
A method for manufacturing an epitaxial wafer including the steps of: preparing a silicon-based substrate having a chamfered portion in a peripheral portion; forming an annular trench in the chamfered portion of the silicon-based substrate along an internal periphery of the chamfered portion; and performing an epitaxial growth on the silicon-based substrate having the trench formed. This provides a method for manufacturing an epitaxial wafer by which a crack generated in a peripheral chamfered portion can be suppressed from extending towards the center.
HIGHLY-TEXTURED THIN FILMS
A superconductor tape and method for fabricating same are disclosed. Embodiments are directed to a superconductor tape including a substrate and a buffer stack. In one embodiment, the buffer stack includes: an Ion Beam-Assisted Deposition (IBAD) template layer above the substrate; a homo-epitaxial film of MgO or TiN above the IBAD template layer; an epitaxial film of silver above the homo-epitaxial film; and a homo-epitaxial film of LaMnO3 (LMO) above the silver epitaxial film. The superconductor tape also includes a superconductor film above the buffer stack. These and other embodiments achieve a LMO film with substantially improved texture, resulting in a superconductor structure having high critical current and significantly reduced power consumption and cost.
UNDERLYING SUBSTRATE
Provided is a ground substrate includes an orientation layer used for crystal growth of a nitride or oxide of a Group 13 element. The front surface of the orientation layer on the side used for the crystal growth is composed of a material having a corundum-type crystal structure having an a-axis length and/or c-axis length larger than that of sapphire. A plurality of pores are present in the orientation layer.
GROUP III NITRIDE SEMICONDUCTOR DEVICE AND PRODUCTION METHOD THEREFOR
The present invention provides a method for producing a Group III nitride semiconductor device which can relax strain between a Group III nitride semiconductor layer containing In and a semiconductor layer adjacent thereto, and a production method therefor. The well layer is a Group III nitride semiconductor layer containing In. The barrier layer is a Group III nitride semiconductor layer. The well layer and the barrier layer are brought into contact with each other in at least one of growing a well layer and growing a barrier layer. A gas containing hydrogen gas as a carrier gas is used in growing a well layer and growing a barrier layer. In growing a barrier layer, the flow rate of hydrogen gas is higher than the flow rate of hydrogen gas in growing a well layer.
Composite substrate and manufacturing method thereof
A composite substrate including a substrate and an aluminum nitride layer is provided. The aluminum nitride layer is disposed on a top surface of the substrate. Silicon is doped in the aluminum nitride layer to regulate residual stress, a film thickness of the aluminum nitride layer is less than 3.5 μm, a defect density of the aluminum nitride layer is less than or equal to 5×10.sup.9/cm.sup.2, and a root mean square roughness of the top surface, facing away from the substrate, of the aluminum nitride layer is less than 3 nm. A manufacturing method of a composite substrate is also provided.
METHOD FOR MANUFACTURING NITRIDE SEMICONDUCTOR SUBSTRATE, NITRIDE SEMICONDUCTOR SUBSTRATE, AND LAMINATE STRUCTURE
A method for manufacturing a nitride semiconductor substrate, including: a step of preparing a base substrate; a step of forming a mask layer having a plurality of openings on the main surface of the base substrate; a first step of growing a first layer whose surface is composed only of inclined interfaces; and a second step of epitaxially growing a single crystal of a group III nitride semiconductor on the first layer, making the inclined interfaces disappear, and growing a second layer having a mirror surface, wherein in the first step, at least one valley and a plurality of tops are formed at an upper side of each of the plurality of openings of the mask layer by forming a plurality of concaves on a top surface of the single crystal and making the (0001) plane disappear.