Abstract: Substrates such as semiconductor wafers are treated with a gas by advancing the substrate along a path, preferably a circular path through the gas while maintaining a face of the substrate transverse, preferably oblique, to the path so that the gas contacts be exposed from the face of the substrate. Preferably, a plurality of substrates are treated simultaneously, and the substrates serve as vanes to impel the gas into rotational motion, thereby pumping the gas through the process chamber. Preferably, the substrates are carried on susceptors having generally planar faces, the susceptors also serving as vanes impelling the gas into rotational motion. The gas may be a depositing gas for forming epitaxial layers on the faces of the substrates, or an etching gas.

Abstract: Substrates such as semiconductor wafers are treated with a gas by advancing the substrate along a path, preferably a circular path through the gas while maintaining a face of the substrate transverse, preferably oblique, to the path so taht the gas contacts be exposed from the face of the substrate. Preferably, a plurality of substrates are treated simultaneously, and the substrates serve as vanes to impel the gas into rotational motion, thereby pumping the gas through the process chamber. Preferably, the substrates are carried on susceptors having generally planar faces, the susceptors also serving as vanes impelling the gas into rotational motion. The gas may be a depositing gas for forming epitaxial layers on the faces of the substrates, or an etching gas.

Abstract: Substrates such as semiconductor wafers are treated with a gas by advancing the substrate along a path, preferably a circular path through the gas while maintaining a face of the substrate transverse, preferably oblique, to the path so that the gas contacts be exposed from the face of the substrate. Preferably, a plurality of substrates are treated simultaneously, and the substrates serve as vanes to impel the gas into rotational motion, thereby pumping the gas through the process chamber. Preferably, the substrates are carried on susceptors having generally planar faces, the susceptors also serving as vanes impelling the gas into rotational motion. The gas may be a depositing gas for forming epitaxial layers on the faces of the substrates, or an etching gas.

Abstract: Apparatus for handling gaseous streams comprising modular flow block means, including a plurality of gas flow paths extending through said modular flow block means so as to provide a plurality of port members on respective surfaces of said modular flow block means, a plurality of valve passages extending into said modular flow block means so as to intercept said gas flow paths at predetermined locations throughout said modular flow block means, each of said plurality of valve passages including an entrance aperture on a respective surface of said modular flow block means, a plurality of valve flange members, each of said valve flange members being adapted to mount a high vacuum valve on said modular flow block means at one of said entrance apertures without the need to apply rotational force to said valve flange members, so as to removably, hermetically seal said high vacuum valve onto said modular flow block means, and each of said plurality of port members including port member mounting means whereby condui

Abstract: A buried double heterostructure laser device isdescribed. A wafer of double heterostructure material is formed into narrow mesa stripes. A native oxide coating is formed on the side walls of the mesa. Semiconductor material having an index of refraction which is closely matched to the index of the active region is deposited over the mesa structure. High resistivity polycrystalline material forms on the native oxide and monocrystalline material forms on the top of the mesa. Vertical carrier and optical confinement is achieved by the higher bandgap cladding layers of the double heterostructure configuration. The native oxide acts as an electrical insulator to confine pumping current to the mesa. The closely matched polycrystalline material confines light parallel to the junction plane and prevents excitation of higher order transverse modes. Devices have been fabricated which exhibit cw threshold currents at room temperature as low as 55 mA.