摘要:
Proposed is an improvement in a vessel, e.g., crucible, of pyrolytic boron nitride (PBN) used, for example, in the process of molecular beam epitaxy for melting silicon and the like at a high temperature. Different from conventional PBN crucibles used for such a process, in which contamination of high-purity silicon is unavoidable by the reaction of molten silicon with PBN or a thermal decomposition products of boron nitride, the inventive PBN vessel is provided on the surface with a protective coating layer of pyrolytic graphite or a refractory metal such as platinum so as not to cause troubles due to contamination of high-purity silicon melted therein with the crucible materials.
摘要:
A ceramic electrostatic chuck with a built-in heater having electrodes of an electroconductive ceramic bonded to a surface of a supporting substrate of an electrically conducting ceramic. A heat generating layer of an electroconductive ceramic is bonded to the other surface of the supporting substrate and a covering layer of an electrically insulating ceramic is provided thereon. Each of the supporting substrate, electrode for the electrostatic chuck and heat generating layer has a surface roughness Rmax of 5 .mu.m or larger.
摘要:
Proposed is a ceramic-based electrostatic chuck with built-in heater used in high-temperature processing of a semiconductor silicon wafer, which is capable of exhibiting excellent electrostatic attracting force even at a temperature at which conventional ceramic-based electrostatic chucks cannot exhibit high attracting force. The electrostatic chuck with built-in heater of the invention is an integral body comprising: (a) a base body of a sintered mixture of boron nitride and aluminum nitride; (b) a first pyrolytic graphite layer formed on one surface of the base body to serve as a resistance heater element; (c) a first insulating layer of pyrolytic boron nitride on the first pyrolytic graphite layer; (d) a second pyrolytic graphite layer formed on the other surface of the base body to serve as the electrodes for electrostatic chucking; and (e) a second insulating layer on the second pyrolytic graphite layer formed from a pyrolytic composite nitride of boron and silicon of which the content of silicon is in the range from 1% to 10% by weight having an appropriate volume resistivity at a temperature of 500.degree. to 650.degree. C. as deposited by the pyrolysis of a gaseous mixture of ammonia, boron trichloride and silicon tetrachloride.
摘要:
Disclosed is an electrolyte membrane-electrode assembly for direct methanol fuel cells, wherein a solid polymer electrolyte membrane is held between a pair of electrodes each composed of a catalyst layer coated over and/or impregnated in a porous supporting body. This electrolyte membrane-electrode assembly for direct methanol fuel cells is characterized in that the solid polymer electrolyte membrane is obtained by irradiating a resin membrane with radiation and graft-polymerizing a radically polymerizable monomer. The electrolyte membrane-electrode assembly for direct methanol fuel cells is further characterized in that the catalyst layer of the anode electrode comprises a catalyst, wherein platinum group metal or platinum-containing alloy particles having a particle size of 5 nm or less are supported by carbon particles, and a solid polymer electrolyte, and the noble metal amount in the catalyst layer of the anode electrode is not more than 5 mg/cm2. By using such a catalyst, there can be obtained a direct methanol fuel cell wherein high output is achieved by using high methanol concentration.
摘要:
A high-performance solid polyelectrolyte film is provided which is produced by the radiation-induced graft polymerization method without causing solution gelation and which is excellent in mechanical strength, chemical stability, and dimensional stability and reduced in methanol permeability. According to the present invention, the solid polyelectrolyte film is produced by graft-polymerizing either a polymerizable monomer having an alkoxysilyl group alone or the polymerizable monomer having an alkoxysilyl group and another polymerizable monomer with a resin film which has been irradiated with a radiation, followed by hydrolyzing the alkoxysilyl groups to conduct dehydrating condensation. In addition, this solid polyelectrolyte film is disposed between a fuel electrode and an air electrode to fabricate a fuel cell.
摘要:
Disclosed is an electrolyte for fuel cells, which is mainly composed of a copolycondensate of a polyimide having an alkoxysilyl group at an end and an alkoxysilane having an ion-conducting group. Also disclosed are an electrolyte membrane for fuel cells, a binder for fuel cells and a membrane electrode assembly for fuel cells, each using the electrolyte, and a fuel cell using such a membrane electrode assembly for fuel cells. The electrolyte enables to obtain an electrolyte membrane, a binder and a membrane electrode assembly, each having high ion conductivity, high strength, high toughness, low swelling and low fuel permeability suitable for fuel cells. By using such an electrolyte, there can be obtained a low-cost fuel cell having high output power and high durability.
摘要:
Disclosed is an electrolyte for fuel cells, which is mainly composed of a copolycondensate of a polyimide having an alkoxysilyl group at an end and an alkoxysilane having an ion-conducting group. Also disclosed are an electrolyte membrane for fuel cells, a binder for fuel cells and a membrane electrode assembly for fuel cells, each using the electrolyte, and a fuel cell using such a membrane electrode assembly for fuel cells. The electrolyte enables to obtain an electrolyte membrane, a binder and a membrane electrode assembly, each having high ion conductivity, high strength, high toughness, low swelling and low fuel permeability suitable for fuel cells. By using such an electrolyte, there can be obtained a low-cost fuel cell having high output power and high durability.
摘要:
A heating device is formed by a heating plate formed of silica and having a heating surface for heating an object to be heated, a heating element having a predetermined pattern and fixed to a surface opposing the heating surface of the heating plate, and a reflecting plate formed of silica and brought into tight contact with the surface of the heating plate on which the heating element is formed. This heating device is arranged in a processing vessel in a CVD apparatus, and a semiconductor wafer is placed on the heating device. A process gas is supplied into the processing vessel while the semiconductor wafer is heated, thereby forming a predetermined film on the semiconductor wafer.
摘要:
The present invention is a negative electrode material for a secondary battery with a non-aqueous electrolyte comprising at least a silicon-silicon oxide composite and a carbon coating formed on a surface of the silicon-silicon oxide composite, wherein at least the silicon-silicon oxide composite is doped with lithium, and a ratio I(SiC)/I(Si) of a peak intensity I(SiC) attributable to SiC of 2θ=35.8±0.2° to a peak intensity I(Si) attributable to Si of 2θ=28.4±0.2° satisfies a relation of I(SiC)/I(Si)≦0.03, when x-ray diffraction using Cu—Kα ray. As a result, there is provided a negative electrode material for a secondary battery with a non-aqueous electrolyte that is superior in first efficiency and cycle durability to a conventional negative electrode material.
摘要:
The present invention relates to a solid polymer electrolyte membrane having both of a higher proton conductivity and a smaller methanol permeability, which can be produced by conducting a graft polymerization of a fluororesin thin membrane irradiated with a radiation with a monofunctional monomer and again irradiating the resulting film with a radiation, followed by conducting a graft polymerization thereof with a polyfunctional monomer; and a high-performance fuel cell comprising the solid polymer electrolyte membrane, a fuel electrode and an air electrode, said solid polymer electrolyte membrane being disposed between the fuel electrode and the air electrode.