A plasma processing device includes: a chamber; a flat-plate-shaped first electrode; a first high frequency power supply; a helical second electrode disposed outside the chamber and disposed to face the first electrode with a quartz plate forming an upper lid of the chamber therebetween; and a gas introducing unit, in which a second high frequency power supply and a third high frequency power supply are configured to be electrically connected to the second electrode, the second high frequency power supply being configured to apply an AC voltage of a second frequency to the second electrode, the third high frequency power supply being configured to apply an AC voltage of a third frequency to the second electrode, and the third frequency being higher than the second frequency; and two types of AC voltages are configured to be simultaneously applied.

A plasma processing device includes: a chamber; a flat-plate-shaped first electrode; a first high frequency power supply; a helical second electrode disposed outside the chamber and disposed to face the first electrode with a quartz plate forming an upper lid of the chamber therebetween; and a gas introducing unit, in which a second high frequency power supply and a third high frequency power supply are configured to be electrically connected to the second electrode, the second high frequency power supply being configured to apply an AC voltage of a second frequency to the second electrode, the third high frequency power supply being configured to apply an AC voltage of a third frequency to the second electrode, and the third frequency being higher than the second frequency; and two types of AC voltages are configured to be simultaneously applied.

A microscale gas breakdown device includes a first surface and a second surface. The first surface and the second surface define a gap distance. The device includes a perturbation on the first surface or the second surface. The perturbation is defined by a height value and a radius value. The device includes a current source or a voltage source configured to apply a current or a voltage across the first surface and the second surface. In response to the current or the voltage being applied, a resulting discharge travels along a first discharge path in response to being exposed to a high pressure and a second discharge path in response to being exposed to a low pressure.

In some embodiments, a gas discharge tube (GDT) can include first and second electrodes each including an edge and an inward facing surface, such that the inward facing surfaces of the first and second electrodes face each other. The GDT can further include a sealing portion implemented to join and seal the edge portions of the inward facing surfaces of the first and second electrodes to define a sealed chamber between the inward facing surfaces of the first and second electrodes. The GDT can further include an electrically insulating portion implemented to provide a surface in the sealed chamber and to cover a portion of the inward facing surface of each of at least one of the first and second electrodes such that a leakage path within the sealed chamber includes the surface of the electrically insulating portion.

In some embodiments, a gas discharge tube (GDT) can include first and second electrodes each including an edge and an inward facing surface, such that the inward facing surfaces of the first and second electrodes face each other. The GDT can further include a sealing portion implemented to join and seal the edge portions of the inward facing surfaces of the first and second electrodes to define a sealed chamber between the inward facing surfaces of the first and second electrodes. The GDT can further include an electrically insulating portion implemented to provide a surface in the sealed chamber and to cover a portion of the inward facing surface of each of at least one of the first and second electrodes such that a leakage path within the sealed chamber includes the surface of the electrically insulating portion.

Provided is a gas discharge tube, including at least two electrodes and an insulating tube body, which is connected in a sealing manner with the electrodes to form a discharge inner cavity. A low-temperature sealing adhesive for sealing the discharge inner cavity is arranged in the gas discharge tube. The low-temperature sealing adhesive is melted at a specific low temperature to cause gas leakage in the discharge inner cavity.

Provided is a gas discharge tube, including at least two electrodes and an insulating tube body, which is connected in a sealing manner with the electrodes to form a discharge inner cavity. A low-temperature sealing adhesive for sealing the discharge inner cavity is arranged in the gas discharge tube. The low-temperature sealing adhesive is melted at a specific low temperature to cause gas leakage in the discharge inner cavity.

A feedthrough device for protecting a system from an electrical transient may include a housing having a first end and a second end spaced apart from the first end in a longitudinal direction. A conductive line may extend through the housing from the first end to the second end of the housing. The conductive line may define an input end proximate the first end of the housing and an output end proximate the second end of the housing for connecting the feedthrough device with the system to be protected. A filter may be disposed within the housing and coupled with the conductive line at a first location. A gas discharge tube may be disposed within the housing and coupled with the conductive line at a second location on the conductive line that is proximate the filter and between the input end of the conductive line and the first location.

A feedthrough device for protecting a system from an electrical transient may include a housing having a first end and a second end spaced apart from the first end in a longitudinal direction. A conductive line may extend through the housing from the first end to the second end of the housing. The conductive line may define an input end proximate the first end of the housing and an output end proximate the second end of the housing for connecting the feedthrough device with the system to be protected. A filter may be disposed within the housing and coupled with the conductive line at a first location. A gas discharge tube may be disposed within the housing and coupled with the conductive line at a second location on the conductive line that is proximate the filter and between the input end of the conductive line and the first location.

Provided is a gas discharge tube, including at least two electrodes and an insulating tube body, which is connected in a sealing manner with the electrodes to form a discharge inner cavity. A low-temperature sealing adhesive for sealing the discharge inner cavity is arranged in the gas discharge tube. The low-temperature sealing adhesive is melted at a specific low temperature to cause gas leakage in the discharge inner cavity.