An apparatus for producing hydrogen radicals, includes (a) a pipe having a cross-sectional area decreasing toward one end from the other thereof, the pipe being composed of metal having a high melting point, (b) a filament for generating heat by running an electrical current therethrough, the filament being disposed in the pipe free of contact with the pipe, and (c) a hydrogen gas source for supplying hydrogen gas to the pipe through the end of the pipe with the larger cross-sectional area. The pipe is electrically isolated from any peripherals, including the filament. The apparatus provides a high production rate of hydrogen radicals, and also prevents gas leakage therefrom, avoiding contamination.
The object of the present invention is to provide a RF induction plasma source generating apparatus which generates a stabilized plasma and sustains the stabilized plasma by maintaining the plasma pressure from several hundreds Torr to several thousands Torr with attachment a buffer nozzle cap, upper metallic blocking films and lower metallic blocking films to a nozzle cap, plasma tube and RF induction coils, respectively for separating the plasma source generating apparatus from the chamber. To accomplish the object of the invention, the plasma source generating apparatus comprising PBN tube, RF induction coils, a nozzle, and a nozzle cap is characterized by a buffer nozzle cap for locating between the nozzle cap and the plasma tube and modulating the flow of the gas to modulate the difference between the chamber pressure and the plasma pressure; sealing films formed by sealing the lips of the buffer nozzle cap, the nozzle cap and the plasma tube for preventing the leakage of gas; and upper blocking films and lower blocking films for blocking the spread out of the RF electric field induced in the RF induction coils and converging the plasma source.
A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.
A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.
A unibody, monolithic, one-piece negative draft crucible for an MBE effusion source. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also includes an effusion source employing such a crucible, as well as a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.
In a semiconductor wafer-processing, hydrogen gas is introduced into the same chamber as used for film formation and heated to generate hydrogen radicals. Alternatively, a plasma is applied to generate hydrogen radicals, or the semiconductor wafer is heated immediately before film formation. Thereby, contaminants on the surface of the wafer are removed. Thereafter, a conductive film or an insulating film is formed on the wafer in the same chamber.
