A plasma processing apparatus includes: a detector configured to detect a change in an intensity of light emission from plasma formed inside a processing chamber; and a unit configured to adjust conditions for forming the plasma or processing a wafer arranged inside the processing chamber using an output from the detector, wherein the detector detects a signal of the intensity of light emission at plural time instants before an arbitrary time instant during processing, and wherein the adjusting unit removes the component of a temporal change of a long cycle of the intensity of light emission from this detected signal and detects the component of a short temporal change of the intensity of light emission, and adjusts the conditions for forming the plasma or processing a wafer arranged inside the processing chamber based on the short temporal change of the detected intensity of light emission.

Apparatus and methods to reduce unwanted magnetic fields and unwanted motion in precision instruments are described. A coil assembly that is used to generate an opposing magnetic field can include a first coil configured to generate a static magnetic field and a second coil configured to generate a time-varying magnetic field. The first and second coils can be in close proximity and sized to suppress magnetic fields over a large localized region. The first coil can be connected to a choke to increase its impedance seen by the second coil.

A radio frequency (RF) screen for a microwave powered ultraviolet (UV) lamp system is disclosed. In one example, a disclosed RF screen includes: a sheet comprising a conductive material; and a frame around edges of the sheet. The conductive material defines a predetermined mesh pattern of individual openings across substantially an operative area of the screen. Each of the individual openings has a triangular shape.

A radio frequency (RF) screen for a microwave powered ultraviolet (UV) lamp system is disclosed. In one example, a disclosed RF screen includes: a sheet comprising a conductive material; and a frame around edges of the sheet. The conductive material defines a predetermined mesh pattern of individual openings across substantially an operative area of the screen. Each of the individual openings has a triangular shape.

An apparatus for forming a three-dimensional article through successively depositing individual layers of powder material that are fused together with an electron beam from an electron beam source so as to form the article according to a computer model thereof. The apparatus includes a chamber a chamber having a first section and a second section openly connected to each other. The first section is configured to receive the individual layers of powder material. The second section comprising an electron beam source, an electromagnetic focus coil having an axially extending, and a reflector coil. The electron beam source is configured to emit an electron beam to fuse the individual layers of powder material. The reflector coil is arranged radially outside the electromagnetic focus coil. The direction of windings of the reflector coil is opposite a direction of windings of the electromagnetic focus coil.

Provided is an electromagnetic field shielding plate, etc., in which it is possible to reduce weight while achieving high shielding performance from relatively high-frequency electromagnetic fields. The electromagnetic field shielding plate is configured by layering a permalloy layer 3 comprising a plate or sheet of permalloy, and an amorphous layer 1 comprising an Fe—Si—B—Cu—Nb-based amorphous plate or sheet.

Disclosed herein is an electron-optical assembly for an electron-optical column for projecting a charged particle beam along a beam path towards a target, the electron-optical assembly comprising: electromagnetic shielding surrounding the charged particle beam path and configured to shield the charged particle beam from an electromagnetic field external to the electromagnetic shielding; wherein the electromagnetic shielding comprises a plurality of sections extending along different positions along the beam path, each section surrounding the charged particle beam, wherein the sections are separable.

A plasma processing apparatus includes: a detector configured to detect a change in an intensity of light emission from plasma formed inside a processing chamber; and a unit configured to adjust conditions for forming the plasma or processing a wafer arranged inside the processing chamber using an output from the detector, wherein the detector detects a signal of the intensity of light emission at plural time instants before an arbitrary time instant during processing, and wherein the adjusting unit removes the component of a temporal change of a long cycle of the intensity of light emission from this detected signal and detects the component of a short temporal change of the intensity of light emission, and adjusts the conditions for forming the plasma or processing a wafer arranged inside the processing chamber based on the short temporal change of the detected intensity of light emission.

The present disclosure provides a lower electrode mechanism and a reaction chamber, the lower electrode mechanism includes a base for carrying a workpiece to be processed and a lower electrode chamber disposed under the base, the lower electrode chamber includes an electromagnetic shielding space and a non-electromagnetic shielding space isolated from each other, the chamber of the lower electrode chamber includes a first through hole and a second through hole, and the electromagnetic shielding space and the non-electromagnetic shielding space are respectively connected to outside through the first through hole and the second through hole to prevent a plurality of first components disposed in the electromagnetic shielding space from being interfered by a second component disposed in the non-electromagnetic shielding space.

A processing chamber includes an upper surface and a showerhead arranged to supply gases through the upper surface into the processing chamber. At least a portion of the showerhead extends above the upper surface of the processing chamber. A shroud enclosure is arranged on the upper surface of the processing chamber. The shroud enclosure is arranged around the portion of the showerhead extending above the upper surface of the processing chamber and is configured to isolate radio frequency interference generated by the showerhead.