A microwave plasma reactor for manufacturing synthetic diamond material via chemical vapour deposition, the microwave plasma reactor comprising: a plasma chamber defining a resonant cavity for supporting a primary microwave resonance mode having a primary microwave resonance mode frequency f; a plurality of microwave sources coupled to the plasma chamber for generating and feeding microwaves having a total microwave power P into the plasma chamber; a gas flow system for feeding process gases into the plasma chamber and removing them therefrom; and a substrate holder disposed in the plasma chamber and comprising a supporting surface for supporting a substrate on which the synthetic diamond material is to be deposited in use, wherein the plurality of microwave sources are configured to couple at least 30% of the total microwave power P into the plasma chamber in the primary microwave resonance mode frequency f, and wherein at least some of the plurality of microwave sources are solid state microwave sources.

Provided is a focalized microwave plasma reactor. The reactor utilizes a cylindrical microwave resonant cavity of the quasi-TM.sub.011 mode to focalize microwave power and to excite focalized microwave plasma for the processes of microwave plasma enhanced chemical vapour depositions.

A plasma reactor has a cylindrical microwave cavity overlying a workpiece processing chamber, a microwave source having a pair of microwave source outputs, and a pair of respective waveguides. The cavity has first and second input ports in a sidewall and space apart by an azimuthal angle. Each of the waveguides has a microwave input end coupled to a microwave source output and a microwave output end coupled to a respective one of the first and second input ports, a coupling aperture plate at the output end with a rectangular coupling aperture in the coupling aperture plate, and an iris plate between the coupling aperture plate and the microwave input end with a rectangular iris opening in the iris plate.

A rotating microwave is established for any resonant mode TE.sub.mnl or TM.sub.mnl of a cavity, where the user is free to choose the values of the mode indices m, n and l. The fast rotation, the rotation frequency of which is equal to an operational microwave frequency, is accomplished by setting the temporal phase difference ?? and the azimuthal angle ?? between two microwave input ports P and Q as functions of m, n and l. The slow rotation of frequency ?.sub.a (typically 1-1000 Hz), is established by transforming dual field inputs ? cos ?.sub.at and ?? sin ?.sub.at in the orthogonal input system into an oblique system defined by the angle ?? between two microwave ports P and Q.

A plasma post-discharge deposition device for depositing crystalline metal oxide derivative on a substrate, the device comprising a gas source with a substrate inlet, a post-discharge deposition chamber with a substrate outlet, the substrate inlet and the substrate outlet defining a longitudinal central axis, and a dielectric tube placed between the gas source and the deposition chamber on the longitudinal central axis; configured to confine a plasma discharge and comprising a discharge zone lying on the internal surface of the dielectric tube and a central zone centred on the longitudinal central axis. The deposition device is remarkable in that the central zone is located at a distance comprised between 1 mm and 2.5 mm from the internal surface of the dielectric tube. Also a plasma-enhanced chemical vapour deposition method.

A rotating microwave is established for any resonant mode TE.sub.mnl or TM.sub.mnl of a cavity, where the user is free to choose the values of the mode indices m, n and l. The fast rotation, the rotation frequency of which is equal to an operational microwave frequency, is accomplished by setting the temporal phase difference ?? and the azimuthal angle ?? between two microwave input ports P and Q as functions of m, n and l. The slow rotation of frequency ?.sub.? (typically 1-1000 Hz), is established by transforming dual field inputs ? cos ?.sub.?t and ?? sin ?.sub.?t in the orthogonal input system into an oblique system defined by the angle ?? between two microwave ports P and Q.

A plasma processing apparatus includes: a processing chamber; a first radio frequency power supply configured to supply a first radio frequency power; a second radio frequency power supply configured to supply a second radio frequency power; and a control device configured to, when the first radio frequency power is modulated by a first waveform having a first period and a second period adjacent to the first period, and the second radio frequency power supply is modulated by a second waveform having a period A and a period B, control the second radio frequency power supply such that each second radio frequency power in the period A is supplied in the first period and the second period, in which an amplitude in the second period is smaller than an amplitude in the first period, and an amplitude in the period A is larger than an amplitude in the period B.

A plasma reactor has a cylindrical microwave cavity overlying a workpiece processing chamber, a microwave source having a pair of microwave source outputs, and a pair of respective waveguides. The cavity has first and second input ports in a sidewall and space apart by an azimuthal angle. Each of the waveguides has a microwave input end coupled to a microwave source output and a microwave output end coupled to a respective one of the first and second input ports, a coupling aperture plate at the output end with a rectangular coupling aperture in the coupling aperture plate, and an iris plate between the coupling aperture plate and the microwave input end with a rectangular iris opening in the iris plate.

A plasma processing apparatus includes a processing vessel; a carrier wave group generating unit configured to generate a carrier wave group including multiple carrier waves having different frequencies belonging to a preset frequency band centered around a predetermined center frequency; and a plasma generating unit configured to generate plasma within the processing vessel by using the carrier wave group.

A plasma processing apparatus includes: a processing container; a substrate holder disposed within the processing container and configured to hold a substrate thereon; a dielectric window disposed below the substrate holder; and a plurality of phased array antennas disposed below the dielectric window and configured to irradiate a plurality of electromagnetic waves.