Transparent pressure barrier for microwave plasma processing

Abstract

This disclosure relates to a reactor including an energy source configured to generate a microwave in a direction of propagation. A reaction chamber is coupled to the energy source. A waveguide disposed in the reactor includes a window positioned at an angle, such as being misaligned, relative to the direction of propagation of the microwave such that an average dielectric constant experienced by the microwave increases over a region where the window occupies a greater fraction of a cross-sectional area of the waveguide. The window includes one or more dielectric materials that have respective dielectric constants that increase along the propagation direction in a first region that is adjacent to a first face of the window, and decrease in a second region that is adjacent to a second face of the window. The dielectric materials have a mass density that varies based on one or more pores formed therein.

Dependencies are inferred from the claim text.