An object is to provide an electron gun that makes it possible to verify whether or not an electron beam emitted form a photocathode is misaligned from a designed emission center axis. The object can be achieved by an electron gun including: a light source; a photocathode; and an anode. The electron gun includes an intermediate electrode arranged between the photocathode and the anode, an electron beam shielding member configured to block a part of an electron beam, a measurement unit configured to measure an intensity of an electron beam blocked by the electron beam shielding member, and an electron beam emission direction deflector arranged between the anode and the electron beam shielding member and configured to change a position where an electron beam that passed through the anode reaches the electron beam shielding member. The intermediate electrode has an electron beam passage hole and a drift space.

An object is to provide an electron gun that makes it possible to verify whether or not an electron beam emitted form a photocathode is misaligned from a designed emission center axis. The object can be achieved by an electron gun including: a light source; a photocathode; and an anode. The electron gun includes an intermediate electrode arranged between the photocathode and the anode, an electron beam shielding member configured to block a part of an electron beam, a measurement unit configured to measure an intensity of an electron beam blocked by the electron beam shielding member, and an electron beam emission direction deflector arranged between the anode and the electron beam shielding member and configured to change a position where an electron beam that passed through the anode reaches the electron beam shielding member. The intermediate electrode has an electron beam passage hole and a drift space.

An ion source has an arc chamber having one or more arc chamber walls defining and interior region of the arc chamber. A cathode electrode is disposed along an axis. A repeller has a repeller shaft and a ceramic target member separated by a gap. The repeller shaft is not in electrical or mechanical contact with the target member, and the repeller shaft is configured to indirectly heat the target member. The target member, can be a cylinder encircling the repeller shaft, where the gap separates the cylinder from the repeller shaft. A top cap can enclose the cylinder can be separated from a top repeller surface of the repeller shaft by the gap. A target hole can be in the top cap. The target member can be supported by a bottom liner of the arc chamber or a support member mechanically and electrically coupled to the repeller shaft.

An ion source for forming a plasma has a cathode with a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially encircling the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, where the cathode gap defines a tortured path for limiting travel of the plasma through the gap. The cathode surface can have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter, where the first cathode diameter and second cathode diameter differ from one another to define the cathode step. The stepped cylindrical surface can be an exterior surface or an interior surface. The first and second cathode diameters can be concentric or axially offset.

An ion source for forming a plasma has a cathode with a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially encircling the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, where the cathode gap defines a tortured path for limiting travel of the plasma through the gap. The cathode surface can have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter, where the first cathode diameter and second cathode diameter differ from one another to define the cathode step. The stepped cylindrical surface can be an exterior surface or an interior surface. The first and second cathode diameters can be concentric or axially offset.

An ion source for forming a plasma has a cathode with a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially encircling the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, where the cathode gap defines a tortured path for limiting travel of the plasma through the gap. The cathode surface can have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter, where the first cathode diameter and second cathode diameter differ from one another to define the cathode step. The stepped cylindrical surface can be an exterior surface or an interior surface. The first and second cathode diameters can be concentric or axially offset.

An ion source for forming a plasma has a cathode with a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially encircling the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, where the cathode gap defines a tortured path for limiting travel of the plasma through the gap. The cathode surface can have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter, where the first cathode diameter and second cathode diameter differ from one another to define the cathode step. The stepped cylindrical surface can be an exterior surface or an interior surface. The first and second cathode diameters can be concentric or axially offset.

An ion source has an arc chamber having one or more arc chamber walls defining and interior region of the arc chamber. A cathode electrode is disposed along an axis. A repeller has a repeller shaft and a ceramic target member separated by a gap. The repeller shaft is not in electrical or mechanical contact with the target member, and the repeller shaft is configured to indirectly heat the target member. The target member, can be a cylinder encircling the repeller shaft, where the gap separates the cylinder from the repeller shaft. A top cap can enclose the cylinder can be separated from a top repeller surface of the repeller shaft by the gap. A target hole can be in the top cap. The target member can be supported by a bottom liner of the arc chamber or a support member mechanically and electrically coupled to the repeller shaft.

A charged particle device includes an electron emitting part for emitting electrons, an electron irradiated part configured to be irradiated with the electrons emitted from the electron emitting part, a container part configured to evacuate an interior thereof and contain the electron irradiated part in the interior thereof, an electric wire containing part configured to be inserted from an outside of the container part via an insertion part provided in the container part to contain an electric wire through which electricity is conducted to the electron irradiated part contained in the container part, and an insertion-part-side protrusion part configured to surround the electric wire containing part and protrude from a vicinity of the insertion part on an inner wall of the container part to an interior of the container part.

A charged particle device includes an electron emitting part for emitting electrons, an electron irradiated part configured to be irradiated with the electrons emitted from the electron emitting part, a container part configured to evacuate an interior thereof and contain the electron irradiated part in the interior thereof, an electric wire containing part configured to be inserted from an outside of the container part via an insertion part provided in the container part to contain an electric wire through which electricity is conducted to the electron irradiated part contained in the container part, and an insertion-part-side protrusion part configured to surround the electric wire containing part and protrude from a vicinity of the insertion part on an inner wall of the container part to an interior of the container part.