Patent classifications
C30B29/48
Method for producing the growth of a semiconductor material
A method for producing the growth of a semiconductor material, in particular of type II-VI, uses a melt of the semiconductor placed in a sealed bulb under vacuum or under controlled atmosphere, the bulb being subjected to a sufficient temperature gradient for first maintaining the melt in the liquid state, then causing its progressive crystallization from the surface towards the bottom. The method further comprises an element capable of floating on the surface of the melt, and equipped with a substantially central bore, intended for receiving a seed crystal for permitting the nucleation leading to the preparation of a seed crystal, and also supporting the seed crystal above the melt while maintaining it in contact with the melt in order to permit the continued crystallization from the seed crystal by lowering the temperature gradient.
Defect reduction using aspect ratio trapping
Lattice-mismatched epitaxial films formed proximate non-crystalline sidewalls. Embodiments of the invention include formation of facets that direct dislocations in the films to the sidewalls.
Defect reduction using aspect ratio trapping
Lattice-mismatched epitaxial films formed proximate non-crystalline sidewalls. Embodiments of the invention include formation of facets that direct dislocations in the films to the sidewalls.
Quantum dot having core-shell structure
A quantum dot having core-shell structure includes a core formed of ZnO.sub.zS.sub.1-z, and at least one shell covering the core, and formed of Al.sub.xGa.sub.yIn.sub.1-x-yN, wherein at least one of x, y, and z is not zero and is not one.
Quantum dot having core-shell structure
A quantum dot having core-shell structure includes a core formed of ZnO.sub.zS.sub.1-z, and at least one shell covering the core, and formed of Al.sub.xGa.sub.yIn.sub.1-x-yN, wherein at least one of x, y, and z is not zero and is not one.
SEMICONDUCTOR WAFER, RADIATION DETECTION ELEMENT, RADIATION DETECTOR, AND PRODUCTION METHOD FOR COMPOUND SEMICONDUCTOR MONOCRYSTALLINE SUBSTRATE
Provided is a stable CdZnTe monocrystalline substrate having a small leakage current even when a high voltage is applied and having a lower variation in resistivity with respect to variations in applied voltage values. A semiconductor wafer comprising a cadmium zinc telluride monocrystal having a zinc concentration of 4.0 at % or more and 6.5 at % or less and a chlorine concentration of 0.1 ppm by mass or more and 5.0 ppm by mass or less, wherein the semiconductor wafer has a resistivity of 1.0×10.sup.7 Ωcm or more and 1.0×10.sup.8 Ωcm or less when a voltage of 900 V is applied, and wherein a ratio (variation ratio) of the resistivity at application of 0 V to the resistivity at application of a voltage of 900 V is 20% or less.
Optical ZnS Material and Preparation Method Thereof
The present invention provides an optical ZnS material and a preparation method thereof, wherein the preparation method comprises: charging zinc and sulfur into a first crucible and a feeding device of a chemical vapor deposition furnace, respectively; heating the first crucible, the second crucible and a deposition chamber, and charging sulfur into the second crucible through the feeding device; introducing an inert carrier gas into the first crucible, and introducing an inert carrier gas and hydrogen into the second crucible, flowing the carrier gas containing zinc vapor and sulfur vapor respectively into the deposition chamber through pipelines to deposit ZnS, and supplying the second crucible with sulfur regularly and quantitatively through the feeding device during the deposition process to maintain a saturated vapor pressure of sulfur in a range of 0.8 to 1.8 KPa. The preparation method of the present invention does not generate H.sub.2S; thus it can avoid the formation of hydrogen-zinc complexes by H ions produced from the decomposition of H.sub.2S and Zn vapor, which would otherwise affect the transmittance and emissivity of ZnS material. (FIG. 4B)
Preparation of nanoparticle materials
A method of producing nanoparticles comprises effecting conversion of a molecular cluster compound to the material of the nanoparticles. The molecular cluster compound comprises a first ion and a second ion to be incorporated into the growing nanoparticles. The conversion can be effected in the presence of a second molecular cluster compound comprising a third ion and a fourth ion to be incorporated into the growing nanoparticles, under conditions permitting seeding and growth of the nanoparticles via consumption of a first molecular cluster compound.
Preparation of nanoparticle materials
A method of producing nanoparticles comprises effecting conversion of a molecular cluster compound to the material of the nanoparticles. The molecular cluster compound comprises a first ion and a second ion to be incorporated into the growing nanoparticles. The conversion can be effected in the presence of a second molecular cluster compound comprising a third ion and a fourth ion to be incorporated into the growing nanoparticles, under conditions permitting seeding and growth of the nanoparticles via consumption of a first molecular cluster compound.
SEMICONDUCTOR WAFER, RADIATION DETECTION ELEMENT, RADIATION DETECTOR, AND PRODUCTION METHOD FOR COMPOUND SEMICONDUCTOR MONOCRYSTALLINE SUBSTRATE
Provided is a CdZnTe monocrystalline substrate which has a small leakage current even when a voltage is applied from a low voltage to a high voltage, and which has a lower variation in resistivity with respect to applied voltage changes from 0 to 900 V, and which can maintain a stable resistivity. A semiconductor wafer comprising a cadmium zinc telluride monocrystal having a zinc concentration of 4.0 at % or more and 6.5 at % or less and a chlorine concentration of 0.1 ppm by weight or more and 5.0 ppm by weight or less, wherein when a voltage is applied in a range of from 0 to 900 V, the semiconductor wafer has a resistivity for each applied voltage value of 1.0×10.sup.7 Ωcm or more and 7.0×10.sup.8 Ωcm or less, and wherein a relative variation coefficient of each resistivity to the applied voltages in a range of from 0 to 900 V is 100% or less.