In accordance with one embodiment of the present invention, an end-Hall ion source has an electron emitting cathode, an anode, a reflector, an internal pole piece, an external pole piece, a magnetically permeable path, and a magnetic-field generating means located in the permeable path between the two pole pieces. The anode and reflector are enclosed without contact by a thermally conductive cup that has internal passages through which a cooling fluid can flow. The closed end of the cup is located between the reflector and the internal pole piece and the opposite end of the cup is in direct contact with the external pole piece, and wherein the cup is made of a material having a low microhardness, such as copper or aluminum.

In accordance with one embodiment of the present invention, an end-Hall ion source has an electron emitting cathode, an anode, a reflector, an internal pole piece, an external pole piece, a magnetically permeable path, and a magnetic-field generating means located in the permeable path between the two pole pieces. The anode and reflector are enclosed without contact by a thermally conductive cup that has internal passages through which a cooling fluid can flow. The closed end of the cup is located between the reflector and the internal pole piece and the opposite end of the cup is in direct contact with the external pole piece, and wherein the cup is made of a material having a low microhardness, such as copper or aluminum.

A crucible that exploits the observation that molten metal tends to flow toward the hottest regions is disclosed. The crucible includes an interior in which dopant material may be disposed. The crucible has a pathway leading from the interior toward an aperture, wherein the temperature is continuously increasing along the pathway. The aperture may be disposed in or near the interior of the arc chamber of an ion source. The liquid metal flows along the pathway toward the arc chamber, where it is vaporized and then ionized. By controlling the flow rate of the pathway, spillage may be reduced. In another embodiment, an inverted crucible is disclosed. The inverted crucible comprises a closed end in communication with the interior of the ion source, so that the closed end is the hottest region of the crucible. An opening is disposed on a different wall to allow vapor to exit the crucible.

A crucible that exploits the observation that molten metal tends to flow toward the hottest regions is disclosed. The crucible includes an interior in which dopant material may be disposed. The crucible has a pathway leading from the interior toward an aperture, wherein the temperature is continuously increasing along the pathway. The aperture may be disposed in or near the interior of the arc chamber of an ion source. The liquid metal flows along the pathway toward the arc chamber, where it is vaporized and then ionized. By controlling the flow rate of the pathway, spillage may be reduced. In another embodiment, an inverted crucible is disclosed. The inverted crucible comprises a closed end in communication with the interior of the ion source, so that the closed end is the hottest region of the crucible. An opening is disposed on a different wall to allow vapor to exit the crucible.

A Hall-effect thruster assembly includes a plurality of magnetic sources for creating a magnetic circuit. The plurality of magnetic sources are positioned between a first end and a second, opposite end of the Hall-effect thruster. The plurality of magnetic sources define a longitudinal axis extending through the first end and the second end. The first end is configured as a discharge end. A mount assembly is coupled to the second end. The mount assembly is configured to secure the plurality of magnetic sources to a spacecraft. A magnetic element is supported by the mount assembly. The magnetic element is positioned relative to the plurality of magnetic sources by the mount assembly.

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 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 accelerator includes: an inner magnet having a channel extending through it in an axial direction; an outer magnet extending around the inner magnet, the magnets having like polarities so as to produce a magnetic field having two locations of zero magnetic field strength. The locations are spaced apart in the axial direction; and an anode and a cathode are arranged to generate an electrical potential difference between the locations.

Plasma processing systems and methods are provided. In one example, a system includes a processing chamber having a workpiece support. The workpiece is configured to support a workpiece. The system includes a plasma source configured to induce a plasma from a process gas in a plasma chamber to generate one or more species of negative ions. The system includes a grid structure configured to accelerate the one or more negative ions towards the workpiece. The grid structure can include a first grid plate, a second grid plate, and one or more magnetic elements positioned between the first grid plate and second grid plate to reduce electrons accelerated through the first grid plate. The system can include a neutralizer cell disposed downstream of the grid structure configured to detach extra electrons from ions of the one or more species of negative ions to generate energetic neutral species for processing the workpiece.

Plasma processing systems and methods are provided. In one example, a system includes a processing chamber having a workpiece support. The workpiece is configured to support a workpiece. The system includes a plasma source configured to induce a plasma from a process gas in a plasma chamber to generate one or more species of negative ions. The system includes a grid structure configured to accelerate the one or more negative ions towards the workpiece. The grid structure can include a first grid plate, a second grid plate, and one or more magnetic elements positioned between the first grid plate and second grid plate to reduce electrons accelerated through the first grid plate. The system can include a neutralizer cell disposed downstream of the grid structure configured to detach extra electrons from ions of the one or more species of negative ions to generate energetic neutral species for processing the workpiece.