A system and method for fabricating a perovskite film is provided, the system including a housing for use as a CVD furnace having first and second sections coupled with first and second temperature control units, respectively. The first and second sections correspond substantially to the upstream and downstream of gases, respectively. One or more substrates are loaded in the second section and controlled by the second temperature control unit, and an evaporation unit containing an organic halide material is loaded in the first section and controlled by the first temperature control unit. Each of the substrates is pre-deposited with a metal halide material. The inside of the housing is pumped down to a low pressure.

A composite diamond body includes a diamond base material and a stable layer disposed on the diamond base material. The stable layer may have a thickness of 0.001 μm or more and less than 10 μm, and may include a plurality of layers. A composite diamond tool includes the composite diamond body. There are thus provided highly wear-resistant composite diamond body and composite diamond tool that are even applicable to mirror-finish planarization of a workpiece which reacts with diamond to cause the diamond to wear.

A composite diamond body includes a diamond base material and a stable layer disposed on the diamond base material. The stable layer may have a thickness of 0.001 μm or more and less than 10 μm, and may include a plurality of layers. A composite diamond tool includes the composite diamond body. There are thus provided highly wear-resistant composite diamond body and composite diamond tool that are even applicable to mirror-finish planarization of a workpiece which reacts with diamond to cause the diamond to wear.

One variation of a method includes: ingesting an air sample captured during an air capture period at a target location for collection of a first mixture including carbon dioxide and a first concentration of impurities; conveying the first mixture through a liquefaction unit to generate a second mixture including carbon dioxide and a second concentration of impurities less than the first concentration of impurities; in a methanation reactor, mixing the second mixture with hydrogen to generate a first hydrocarbon mixture comprising a third concentration of impurities comprising nitrogen, carbon dioxide, and hydrogen; conveying the first hydrocarbon mixture through a separation unit configured to remove impurities from the first hydrocarbon mixture to generate a second hydrocarbon a fourth concentration of impurities less than the third concentration of impurities; and depositing the second hydrocarbon mixture in a diamond reactor containing a set of diamond seeds to generate a first set of diamonds.

One variation of a method includes: ingesting an air sample captured during an air capture period at a target location for collection of a first mixture including carbon dioxide and a first concentration of impurities; conveying the first mixture through a liquefaction unit to generate a second mixture including carbon dioxide and a second concentration of impurities less than the first concentration of impurities; in a methanation reactor, mixing the second mixture with hydrogen to generate a first hydrocarbon mixture comprising a third concentration of impurities comprising nitrogen, carbon dioxide, and hydrogen; conveying the first hydrocarbon mixture through a separation unit configured to remove impurities from the first hydrocarbon mixture to generate a second hydrocarbon a fourth concentration of impurities less than the third concentration of impurities; and depositing the second hydrocarbon mixture in a diamond reactor containing a set of diamond seeds to generate a first set of diamonds.

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)

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)

A diode includes an n-type semiconductor layer including an n-type Ga.sub.2O.sub.3-based single crystal, and a p-type semiconductor layer including a p-type semiconductor in which a volume of an amorphous portion is higher than a volume of a crystalline portion. The n-type semiconductor layer and the p-type semiconductor layer form a pn junction.

A biomedical implant (16, 18) is formed from magnesium (Mg) single crystal (10). The biomedical implant (16, 18) may be biodegradable. The biomedical implant (16, 18) may be post treated to control the mechanical properties and/or corrosion rate thereof said Mg single crystal (10) without changing the chemical composition thereof. A method of making a Mg single crystal (10) for biomedical applications includes filling a single crucible (12) with more than one chamber with polycrystalline Mg, melting at least a portion of said polycrystalline Mg, and forming more than one Mg single crystal (10) using directional solidification.

A biomedical implant (16, 18) is formed from magnesium (Mg) single crystal (10). The biomedical implant (16, 18) may be biodegradable. The biomedical implant (16, 18) may be post treated to control the mechanical properties and/or corrosion rate thereof said Mg single crystal (10) without changing the chemical composition thereof. A method of making a Mg single crystal (10) for biomedical applications includes filling a single crucible (12) with more than one chamber with polycrystalline Mg, melting at least a portion of said polycrystalline Mg, and forming more than one Mg single crystal (10) using directional solidification.