In a state in which a SiC container (3) of a material including polycrystalline SiC is housed in a TaC container (2) of a material including TaC and in which an underlying substrate (40) is housed in the SiC container (3), the TaC container (2) is heated in an environment where a temperature gradient occurs in such a manner that inside of the TaC container (2) is at a Si vapor pressure. Consequently, C atoms sublimated by etching of the inner surface of the SiC container (3) are bonded to Si atoms in an atmosphere so that an epitaxial layer (41) of single crystalline 3C-SiC thereby grows on the underlying substrate (40).

A method for preparing a SiC ingot includes preparing a crucible assembly comprising a crucible body having an internal space, loading a raw material into the internal space of the crucible body and placing a plurality of SiC seed in the internal space of the crucible body at regular intervals spaced apart from the raw material, and growing the SiC ingot from the plurality of SiC seed by adjusting the internal space of the crucible body to a crystal growth atmosphere such that the raw material is vapor-transported and deposited to the plurality of SiC seed. A density of the crucible body may be 1.70 to 1.92 g/cm.sup.3.

The present invention addresses the problem of providing a novel SiC epitaxial substrate manufacturing method and manufacturing device therefor. An SiC substrate and an SiC material, which has a lower doping concentration than said SiC substrate, are heated facing one another, and material is transported from the SiC material to the SiC substrate to form an SiC epitaxial layer. As a result, in comparison with the existing method (chemical vapour deposition), it is possible to provide an SiC epitaxial substrate manufacturing method with a reduced number of parameters to be controlled.

A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

A silicon carbide ingot manufacturing method and a silicon carbide ingot manufacturing system are provided. The silicon carbide ingot manufacturing method and the silicon carbide ingot manufacturing system may change a temperature gradient depending on the growth of an ingot by implementing a guide which has a tilted angle to an external direction from the interior of a reactor, in an operation to grow an ingot during a silicon carbide ingot manufacturing process.

Methods for making metastable lead-free piezoelectric materials are presented herein.

Disclosed is a method for manufacturing a piezoelectric Al.sub.xGa.sub.1-xN (0.5≤x≤1) thin film, comprising: forming a stress control layer comprised of a Group III nitride on a silicon substrate by chemical vapor deposition (CVD); and depositing a piezoelectric Al.sub.xGa.sub.1-xN (0.5≤x≤1) thin film on the stress control layer, the thin film being deposited by PVD at 0.3 Tm (Tm is melting temperature of a piezoelectric thin film material) or higher. Further, a method for manufacturing a device in conjunction with piezoelectric Al.sub.xGa.sub.1-xN (0.5≤x≤1) thin films is provided.

Described herein are an SiC material and a method for manufacturing same. The SiC material includes an SiC layer having a low thermal conductivity region formed in at least a portion thereof, wherein the low thermal conductivity region has an average crystal grain size of 3.5 μm or less and (111) plane preferential growth according to X-ray diffraction analysis.

A deposition system is disclosed that allows for growth of inclined c-axis piezoelectric material structures. The system integrates various sputtering modules to yield high quality films and is designed to optimize throughput lending it to a high-volume in manufacturing environment. The system includes two or more process modules including an off-axis module constructed to deposit material at an inclined c-axis and a longitudinal module constructed to deposit material at normal incidence; a central wafer transfer unit including a load lock, a vacuum chamber, and a robot disposed within the vacuum chamber and constructed to transfer a wafer substrate between the central wafer transfer unit and the two or more process modules; and a control unit operatively connected to the robot.

Methods for purifying reaction precursors used in the synthesis of inorganic compounds and methods for synthesizing inorganic compounds from the purified precursors are provided. Also provided are methods for purifying the inorganic compounds and methods for crystallizing the inorganic compounds from a melt. γ and X-ray detectors incorporating the crystals of the inorganic compounds are also provided.