A plasma processing device comprising a chamber ( 1 ), a high-frequency power supply and an antenna unit ( 3 ) The antenna unit ( 3 ) comprises a slot plate ( 3 c ) , a slow wave plate ( 3 b ) and an antenna cover ( 3 a )  A top plate unit ( 4 ) having a flat plate ( 4 a ) and sidewalls ( 4 b ) is disposed at the upper portion of the chamber ( 1 ) The flat plate ( 4 a ) contacts the slot plate ( 3 c ) disposed to face a housed substrate ( 11 ) The sidewalls ( 4 b ) are formed so as to extend toward a substrate-disposed side from the periphery of the flat plate ( 4 a )  The outer periphery surfaces of sidewalls ( 4 b ) contact the chamber ( 1 ) The thickness of the sidewalls ( 4 b ) is set to be at least λ g /4, where λ g is the wavelength of a microwave based on the permittivity of the top plate ( 4 ) Accordingly, a plasma density can be further increased and a uniformity in plasma density distribution can be improved

Plasma processing device

Broadband High-Power Microwave Window Assembly A window assembly for a hollow waveguide of circular cross-section, with improved bandwidth and cooling capability for handling high microwave power transmissions over wide frequency ranges t is disclosed. A plate or disc of dielectric of refractive index n1 extends sealingly across the waveguide and has two parallel faces which exhibit a pattern of corrugations. One of these faces is in contact with a dielectric fluid of refractive index n2, and apparatus is provided for cooling and circulating the fluid over said one face. Each of the corrugations extends into the fluid a distance proportional to the inverse of the geometric mean of the product of the refractive indices n1, n2. In a preferred embodiment, a second plate is included, separated from the first by a region in which said dielectric fluid is circu-lated, and in which at least both the faces in con-tact with the fluid are corrugated. The corruga-tions not only result in greatly improved matching over a broad band, but also greatly improved fluid flow and surface contact thereof over said one face, for enhanced cooling and thus power handling capa-bility of the window assembly.

Broadband high-power microwave window assembly

A window assembly for transmitting relatively high power microwave energy from a waveguide, held at substantially atmospheric pressure levels, into a microwave reaction chamber at sub-atmospheric pressure levels. The window assembly provides for the transmission of microwave energy to generate a glow discharge plasma without suffering from catastrophic failure as a result of excessive temperature and pressure conditions.

Microwave plasma operation using a high power microwave transmissive window assembly

A hermetically sealed electromagnetic window is formed by butt end brazing an overhanging dielectric window between first and second waveguide segments. The waveguide segments have opposed knife edges with a dielectric insert positioned between the knife edges. A pair of brazing forms are inserted between the insert and the two knife edges. The window is heated, causing the brazing material to reflow and provide a hermetic seal between the insert and the waveguide segments, and a conductive path between the waveguide segments.

Hermetically sealed electromagnetic window and method of forming the same

A distributed microwave window couples microwave power in the HE11 mode between a first large diameter waveguide and a second large diameter waveguide, while providing a physical barrier between the two waveguides, without the need for any transitions to other shapes or diameters. The window comprises a stack of alternating dielectric and hollow metallic strips, brazed together to form a vacuum barrier. The vacuum barrier is either transverse to or tilted with respect to the waveguide axis. The strips are oriented to be perpendicular to the transverse electric field of the incident microwave power. A suitable coolant flows through the metallic strips. The metallic strips are tapered on both sides of the vacuum barrier, which taper serves to funnel the incident microwave power through the dielectric strips. The surfaces of the dielectric strips fronting the microwave power may be corrugated in a specified manner to reduce losses.

Distributed window for large diameter waveguides

For conducting very high microwave power at very high frequencies, circular waveguide transmitting a circular-electric-field mode is used. The vacuum-tight window of an electron tube is often the element with lowest power-handling capability. The inventive window has two dielectric plates with a space between them. There is a gap in the waveguide inner wall through which a dielectric fluid is circulated between the plates to cool them. The gap leads to a region containing wave-absorbing material such as water to absorb modes other than the circular-electric-field mode.

Mizuhara Yosuke Maxwell

Papers

Circular electric mode microwave window

Circular mode microwave window

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