An ion source having a thermally isolated repeller is disclosed. The repeller comprises a repeller disk and a plurality of spokes originating at the back surface of the repeller disk and terminating in a post. In certain embodiments, the post may be hollow through at least a portion of its length. The use of spokes rather than a central stem may reduce the thermal conduction from the repeller disk to the post. By incorporating a hollow post, the thermal conduction is further reduced. This configuration may increase the temperature of the repeller disk by more than 100° C. In certain embodiments, radiation shields are provided on the back surface of the repeller disk to reduce the amount of radiation emitted from the sides of the repeller disk. This may also help increase the temperature of the repeller. A similar design may be utilized for other electrodes in the ion source.

An inner source assembly for a mass spectrometer, the assembly comprising: a base; and a volume housing removably connectable to the base for retaining a repeller assembly therebetween, wherein one of the base and volume housing comprises at least two protrusions and the other of the volume housing and base comprises at least two corresponding slots to receive and retain said protrusions, wherein the protrusions are dissimilar to one another and/or the slots are dissimilar to one another.

An ion source can include a magnetic field generator configured to generate a magnetic field in a direction parallel to a direction of the electron beam and coincident with the electron beam. However, this magnetic field can also influence the path of ionized sample constituents as they pass through and exit the ion source. An ion source can include an electric field generator to compensate for this effect. As an example, the electric field generator can be configured to generate an electric field within the ion source chamber, such that an additional force is imparted on the ionized sample constituents, opposite in direction and substantially equal in magnitude to the force imparted on the ionized sample constituents by the magnetic field.

The disclosure describes various aspects of a shed-resistant thermal atom source. More specifically, a thermal atom source is described for uniform thermal flux of target atomic species in which a metal wadding material is used as an intermediary surface for sublimation of the atoms, preventing the source material from shedding or dropping. In an aspect, a thermal atom source may include a container with closed and open ends, and inside a source material near the closed end and a wadding between the source material and the open end; a heater coupled to the closed end; one or more clamps configured to secure the container and the heater; and a current source coupled to the container and the heater to cause a temperature to increase such that a portion of the source material is released and diffuses to the open end through the wadding prior to being emitted as a flux.

Disclosed herein are approaches for adjusting extraction slits of an extraction plate using a set of adjustable beam blockers. In one approach, an ion extraction optics may include an extraction plate including a first opening and a second opening, and a first beam blocker extending over the first opening and a second beam blocker extending over the second opening. Each of the first and second beam blockers may include an inner slit defined by a first distance between an inner edge and the extraction plate, and an outer slit defined by a second distance between an outer edge and the extraction plate, wherein the first and second beam blockers are movable to vary at least one of the first distance and the second distance. As a result, extraction through the inner and outer slits of ion beamlets characterized by similar mean angles may be achieved.

The present invention discloses an ionization apparatus 10 for ionizing an analyte S, comprising an inlet E, an outlet A, a first electrode 1, a second electrode 2 and a dielectric element 3. The first electrode 1, the second electrode 2 and the dielectric element 3 are arranged relative to one another such that, by applying an electric voltage between the first electrode 1 and the second electrode 2, a dielectric barrier discharge is establishable in a discharge area 5 in the ionization apparatus 10. The first and second electrodes 1, 2 are arranged such that they are displaceable or movable relative to each other.

An ion source is provided that includes a gas source for supplying a gas, and an ionization chamber defining a longitudinal axis extending therethrough and including an exit aperture along a side wall of the ionization chamber. The ion source also includes one or more extraction electrodes at the exit aperture of the ionization chamber for extracting ions from the ionization chamber in the form of an ion beam. At least one of the extraction electrodes comprises a set of discrete rods forming a plurality of slits in the at least one extraction electrode for enabling at least one of increasing a current of the ion beam or controlling an angle of extraction of the ion beam from the ionization chamber. Each rod in the set of discrete rods is parallel to the longitudinal axis of the ionization chamber.

Provided is an ion beam processing apparatus including an ion generation chamber, a processing chamber, and electrodes to form an ion beam by extracting ions generated in the ion generation chamber to the processing chamber. The electrodes includes a first electrode disposed close to the ion generation chamber and provided with an ion passage hole to allow passage of the ions, and a second electrode disposed adjacent to the first electrode and closer to the processing chamber than the first electrode is, and provided with an ion passage hole to allow passage of the ions. The apparatus also includes a power unit which applies different electric potentials to the first electrode and the second electrode, respectively, so as to accelerate the ions generated by an ion generator in the ion generation chamber. A material of the first electrode is different from a material of the second electrode.

An H.sub.3.sup.+ ion is used as an ion beam to achieve improvement in focusing capability influencing observed resolution and machining width, improvement in the beam stability, and a reduction in damage to the sample surface during the beam irradiation, in the process of observation and machining of the sample surface by the ion beam. The H.sub.3.sup.+ ion can be obtained by use of a probe current within a voltage range 21 around a second peak 23 occurring when an extracted voltage is applied to a needle-shaped emitter tip with an apex terminated by three atoms or less, in an atmosphere of hydrogen gas.

An inner source assembly for a mass spectrometer, the assembly comprising: a base; and a volume housing removably connectable to the base for retaining a repeller assembly therebetween, wherein one of the base and volume housing comprises at least two protrusions and the other of the volume housing and base comprises at least two corresponding slots to receive and retain said protrusions, wherein the protrusions are dissimilar to one another and/or the slots are dissimilar to one another.