Abstract: An integrated phase separator for use in an ultra high vacuum system, for example, a molecular beam epitaxy system, is described. The vacuum chamber has a cryogenic panel disposed therein. The cryogenic panel includes a cryogenic shroud region and a phase separator region. Liquid nitrogen is introduced into the cryogenic panel via an inlet line. As the liquid nitrogen warms and vaporizes, nitrogen vapor rises within the shroud. The phase separator region within the cryogenic panel provides a near atmospheric pressure vapor barrier over the liquid nitrogen so that the nitrogen vapor may escape smoothly through the outlet of the panel, without forming gas bursts. Also, the phase separator region is vacuum jacketed to prevent cryogenic shroud surface temperature changes due to variations in liquid nitrogen levels, thereby increasing the cryogenic shroud's pumping stability. In one embodiment, used in molecular beam epitaxy (MBE), the cryopanel is divided into first and second cooling chambers.
Abstract: An integrated phase separator for use in an ultra high vacuum system, for example, a molecular beam epitaxy system, is described. The vacuum chamber has a cryogenic panel disposed therein. The cryogenic panel includes a cryogenic shroud region and a phase separator region. Liquid nitrogen is introduced into the cryogenic panel via an inlet line. As the liquid nitrogen warms and vaporizes, nitrogen vapor rises within the shroud. The phase separator region within the cryogenic panel provides a near atmospheric pressure vapor barrier over the liquid nitrogen so that the nitrogen vapor may escape smoothly through the outlet of the panel, without forming gas bursts. Also, the phase separator region is vacuum jacketed to prevent cryogenic shroud surface temperature changes due to variations in liquid nitrogen levels, thereby increasing the cryogenic shroud's pumping stability. In one embodiment, used in molecular beam epitaxy (MBE), the cryopanel is divided into first and second cooling chambers.
Abstract: The present invention relates to an improved structure of the “showerhead used to introduce gaseous source material into a vapor deposition reactor such as a metal-organic chemical vapor deposition (MOCVD) reactor. The showerhead includes inlet seal assemblies that connect the inlet lines to the showerhead through the use of opposing planar seal faces so as to simplify the process of connecting and disconnecting the inlet lines to the showerhead. In addition, the showerhead includes a gas dispersion assembly on the inner face of the showerhead that optimizes the flow of gaseous material into the reaction chamber. The gas dispersion assembly includes a plurality of webbed disks that define discrete dispersion chambers. The webbed disks include integrally-formed flow diverters that direct the flow of gas into the dispersion chambers so as to create a controlled, uniform flow of material into the reaction chamber.
Abstract: An integrated phase separator for use in an ultra high vacuum system, for example, a molecular beam epitaxy system, is described. The vacuum chamber has a cryogenic panel disposed therein. The cryogenic panel includes a cryogenic shroud region and a phase separator region. Liquid nitrogen is introduced into the cryogenic panel via an inlet line. As the liquid nitrogen warms and vaporizes, nitrogen vapor rises within the shroud. The phase separator region within the cryogenic panel provides a near atmospheric pressure vapor barrier over the liquid nitrogen so that the nitrogen vapor may escape smoothly through the outlet of the panel, without forming gas bursts. Also, the phase separator region is vacuum jacketed to prevent cryogenic shroud surface temperature changes due to variations in liquid nitrogen levels, thereby increasing the cryogenic shroud's pumping stability.