Abstract: A chemical vapor deposition apparatus comprising a hot wall reaction tube, one or more reaction gas preheaters, a reaction gas exhaust outlet, and substantially eddy free reaction gas flow control means for passing reaction gases in a substantially laminar flow from a preheater to the exhaust outlet. The gas flow control means includes a tube flange positioned to be in a substantially eddy free relationship with the end of the wafer boat zone, the flange having a curved surface means extending from the end of the wafer boat zone to the outer tube for directing the reaction gas flow out of or into the reaction zone while maintaining the gas in a state of substantially laminar flow. One reaction gas preheater comprises a first heating tube having a removable baffle. A second reaction gas preheater comprises a two wall cylindrical heater with inner surface deformations.

Abstract: Process for depositing tungsten or other refractory metals on semiconductor devices by a reaction of a gas containing the metal in a vapor deposition reactor. The reaction occurs at relatively low temperature (240.degree.-400.degree. C.) and pressure (0.1-10 torr), and the resulting film adheres differently to different substrate materials. Patterned coatings can be made without the patterning steps which are required with prior art techniques.

Abstract: A chemical vapor deposition device having uniformly distributed heating means substantially surrounding an inner deposition reaction chamber for providing isothermal or precisely controlled gradient temperature conditions therein, the reaction chamber being surrounded by the walls of an outer vacuum chamber spaced therefrom.

Abstract: A chemical vapor deposition device having uniformly distributed heating means substantially surrounding an inner deposition reaction chamber for providing isothermal or precisely controlled gradient temperature conditions therein, the reaction chamber being surrounded by the walls of an outer vacuum chamber spaced therefrom.

Abstract: An improved chemical vapor deposition device having heating means substantially surrounding an inner deposition chamber for providing isothermal or precisely controlled gradient temperature conditions therein. The internal components of the chamber are quartz or similar radiant energy transparent material. Also included are special cooling means to protect thermally sensitive seals, structural configurations strengthening areas of glass components subjected to severe stress during operation, and specific designs permitting easy removal and replacement of all glass components exposed to deposition gas.

Abstract: A controlled temperature deposition device comprising an inner reaction chamber having gas distribution means for introducing gas into inner chamber and removing gas therefrom and a vacuum chamber means surrounding the inner deposition chamber and spaced from the walls thereof for maintaining a medium vacuum therein. Associated with the deposition device is a substrate loading and unloading fork which transfers substrates such as wafer boats from outside the device to a position in the inner deposition chamber and removes them from the inner deposition chamber following deposition.