The IHC ion source comprises an ion source chamber having a cathode and a repeller on opposite ends. The ion source chamber is constructed of a ceramic material having very low electrical conductivity. An electrically conductive liner may be inserted into the ion source chamber and may cover three sides of the ion source chamber. The liner may be electrically connected to the faceplate, which contains the extraction aperture. The electrical connections for the cathode and repeller pass through apertures in the ceramic material. In this way, the apertures may be made smaller than otherwise possible as there is no risk of arcing. In certain embodiments, the electrical connections are molded into the ion source chamber or are press fit in the apertures. Further, the ceramic material used for the ion source chamber is more durable and introduces less contaminants to the extracted ion beam.

In order to attain a main objective of the present invention to provide an ion source capable of efficiently extracting ions, the ion source is configured to include: a conductive tubular body having an ion emitting aperture in a tip surface thereof and a penetration portion in a side wall thereof allowing thermo-electrons to pass through from an outside toward an inside; a mesh surrounding an outer periphery of the penetration portion; and a thermionic emission filament surrounding an outer periphery of the mesh, such that the thermo-electrons emitted from the thermionic emission filament pass through the mesh and reach the inside of the conductive tubular body through the penetration portion.

An apparatus to generate negative hydrogen ions. The apparatus may include an ion source chamber having a gas inlet to receive H.sub.2 gas; a light source directing radiation into the ion source chamber to generate excited H.sub.2 molecules having an excited vibrational state from at least some of the H.sub.2 gas; a low energy electron source directing low energy electrons into the ion source chamber, wherein H.sup. ions are generated from at least some of the excited H.sub.2 molecules; and an extraction assembly arranged to extract the H.sup. ions from the ion source chamber.

The IHC ion source comprises an ion source chamber having a cathode and a repeller on opposite ends. The ion source chamber is constructed of a ceramic material having very low electrical conductivity. An electrically conductive liner may be inserted into the ion source chamber and may cover three sides of the ion source chamber. The liner may be electrically connected to the faceplate, which contains the extraction aperture. The electrical connections for the cathode and repeller pass through apertures in the ceramic material. In this way, the apertures may be made smaller than otherwise possible as there is no risk of arcing. In certain embodiments, the electrical connections are molded into the ion source chamber or are press fit in the apertures. Further, the ceramic material used for the ion source chamber is more durable and introduces less contaminants to the extracted ion beam.

The IHC ion source comprises an ion source chamber having a cathode and a repeller on opposite ends. The repeller is made of two discrete parts, each comprising a different material. The repeller includes a repeller head, which may be a disc shaped component, and a stem to support the head. The repeller head is made from a conductive material having a higher thermal conductivity than the stem. In this way, the temperature of the repeller head is maintained at a higher temperature than would otherwise be possible. The higher temperature limits the build-up of material on the repeller head, which improves the performance of the IHC ion source. In certain embodiments, the repeller head and the stem are connected using a press fit. Differences in the coefficient of thermal expansion of the repeller head and the stem may cause the press fit to become tighter at higher temperatures.

An ion source having improved life is disclosed. In certain embodiments, the ion source is an IHC ion source comprising a chamber, having a plurality of electrically conductive walls, having a cathode which is electrically connected to the walls of the ion source. Electrodes are disposed on one or more walls of the ion source. A bias voltage is applied to at least one of the electrodes, relative to the walls of the chamber. In certain embodiments, fewer positive ions are attracted to the cathode, reducing the amount of sputtering experienced by the cathode. Advantageously, the life of the cathode is improved using this technique. In another embodiment, the ion source comprises a Bernas ion source comprising a chamber having a filament with one lead of the filament connected to the walls of the ion source.

In order to attain a main objective of the present invention to provide an ion source capable of efficiently extracting ions, the ion source is configured to include: a conductive tubular body having an ion emitting aperture in a tip surface thereof and a penetration portion in a side wall thereof allowing thermo-electrons to pass through from an outside toward an inside; a mesh surrounding an outer periphery of the penetration portion; and a thermionic emission filament surrounding an outer periphery of the mesh, such that the thermo-electrons emitted from the thermionic emission filament pass through the mesh and reach the inside of the conductive tubular body through the penetration portion.

In an ion source 3 in which a repeller electrode 32 for forming a repelling electric field that repels ions toward an ion emission port 311 is provided inside of an ionization chamber 31, ion focusing electrodes 36 and 37 are respectively arranged between an electron introduction port 312 and a filament 34 and between an electron discharge port 313 and a counter filament 35. An electric field formed by applying a predetermined voltage to each of the ion focusing electrodes 36 and 37 intrudes into the ionization chamber 31 through the electron introduction port 312 and the electron discharge port 313, and becomes a focusing electric field that pushes the ions in an ion optical axis C direction. Ions at positions off a central part of the ionization chamber 31 receive the combined force of the force of the repelling electric field and the force of the focusing electric field, and move toward the ion emission port 311 while approaching the ion optical axis C. Accordingly, the amount of ions sent out from the ion emission port increases. Further, even if a charge-up phenomenon occurs, the ion trajectories less easily change, and the stability of the sensitivity can be enhanced.

A device 1 for generating a controlled ionic flow I is described. The device 1 is portable and comprises an ionization chamber 6, at least one inlet member 2 and at least one ion outlet member 3. The ionization chamber 6 is suitable to be kept at a vacuum pressure, and configured to ionize gaseous particles contained therein. The at least one inlet member 2 is configured to inhibit or allow and/or adjust an inlet in the ionization chamber of a gaseous flow Fi of said gaseous particles. In addition, the at least one inlet member 2 comprises a gaseous flow adjusting interface 22, having a plurality of nano-holes 20, of sub-micrometric dimensions, suitable to be opened or closed, in a controlled manner, to inhibit or allow a respective plurality of gas micro-flows through the at least one inlet member 2.

An indirectly heated cathode (IHC) ion source having improved life is disclosed. The IHC ion source comprises a chamber having a cathode and a repeller on opposite ends of the ion source. Biased electrodes are disposed on one or more sides of the ion source. The bias voltage applied to at least one of the cathode, the repeller and the electrodes, relative to the chamber, is varied over time. In certain embodiments, the voltage applied to the electrodes may begin at an initial positive voltage. Over time, this voltage may be reduced, while still maintaining the target ion beam current. Advantageously, the life of the cathode is improved using this technique.