Device and method for high resolution beam analysis

Abstract

The present invention provides devices and methods for recording spectral information of charged particle beams, such as ion beams, or of light beams with high resolution. In particular, a mass spectrometer having a focal plane detector is disclosed. The present invention enables recording of mass spectral data with both high mass resolution and mass accuracy while acquiring, in some cases, the entire spectrum of the sample beam in parallel.

Description

[Technical Field]

[0001] The present invention is in the field of charged particle or light detection devices and methods, and in particular relates to analytical devices such as mass spectrometers requiring high mass resolution and mass accuracy, including but not limited to secondary ion mass spectrometers (SIMS). [Background technology]

[0002] In known mass spectrometer devices, an ion beam carrying various species of ions extracted from a sample is analyzed by separating the constituent ion species, where each ion species has a given mass-to-charge ratio. Similarly, in optical spectroscopy, a spectrometer separates the various wavelengths carried by a light beam. In known magnetic sector mass spectrometer devices, an electrostatic sector is followed downstream in the direction of the ion beam by a magnetic sector instrument. The arrangement of the electrostatic and magnetic sectors typically allows for a wide distribution of ion masses (m / z) along the exit face of the magnetic sector. A detector can then collect and count the ions of each beam at various locations along the distribution range. The collected data indicates mass-to-charge ratios corresponding to distances along the detector and ion intensities corresponding to the ion species counted for each mass-to-charge ratio, forming a mass spectral representation of the sample.

[0003] Sector field type mass analyzers with focal planes covering a wide mass range are generally classified as Mattauch-Herzog mass analyzers. All ion masses m / z are focused at the exit plane (in the original Mattauch-Herzog configuration) or on a focal plane located some distance from the exit plane of the magnetic sector. Most Mattauch-Herzog mass analyzers can be operated in double focusing conditions (achromatic mass filtering) to obtain the highest mass resolution. Typical mass resolutions of several hundred to several thousand are achieved in known devices.

[0004] An interesting feature of this type of analyzer device is its ability to simultaneously capture a wide range of ion species when equipped with an appropriate detection system with a focal plane detector. Focal plane detectors allow for simultaneous acquisition of entire mass spectra, typically with short acquisition times of a fraction of a second. This simultaneous acquisition capability offers several advantages. First, a 100% duty cycle of measurements can be achieved. This advantage allows for better detection limits and reduced sample sizes required for measurements because peaks of all mass-to-charge ratios (m / z) are collected simultaneously. Second, the ability to simultaneously record entire mass spectra allows for the use of both continuous and pulsed ionization techniques. In particular, pulsed ionization techniques, such as laser ablation / ionization, typically introduce abrupt changes in the spectral signal, which can result in measurement errors when using continuous detection techniques.

[0005] Focal plane detectors based on microchannel plates have the great advantage of being extremely sensitive (detection of single ions / electrons) due to their high amplification gain capability. Such focal plane detectors also offer flexibility in terms of shape and size to fit within individual instruments. Detectors can be designed with lengths ranging from a few to several centimeters. For this reason, MCP-based detector technology is currently the most popular for mass spectrometry and secondary ion mass spectrometry (SIMS) applications.

[0006] A typical microchannel plate (MCP) device is 10 4 From 10 7 MCPs consist of small electron multipliers with typical diameters in the range of 10 to 100 μm. Each channel functions as an individual electron multiplier capable of detecting single ions, electrons, atoms, molecules, or photons. MCPs are generally fabricated from highly resistive materials such as leaded glass. The front and back surfaces of the MCP are metallized electrodes across which a voltage difference, typically about 1000 V, is applied through a suitable biasing means such as a power supply. When a single high-energy particle strikes the channel surface, it creates one or more secondary electrons, which are accelerated by the applied voltage and enter the MCP channel. Each of these secondary electrons can release two or more secondary electrons when it strikes the channel wall again. This process occurs in a cascade manner along the channel. Thus, a single energetic particle striking the channel creates a cascade of electron emissions along the channel, resulting in at least 10 4 An electron cloud of electrons is generated. An anode placed behind the MCP can electronically detect this electron cloud and register each single event that strikes the MCP.

[0007] Each MCP typically has 10 4 However, most applications require a higher gain (10 6 -10 7) is required. To achieve this gain increase, several MCPs stacked in series can be used. When using stacked MCPs, each MCP in the first layer has its channels tilted 8°–15° relative to the MCP normal. The channels of the MCP in the next layer are tilted in the opposite direction to avoid ion feedback from successively stacked MCPs. An assembly combining two stacked MCPs in this configuration is called a chevron assembly, while an assembly combining three MCPs is called a Z-stack assembly. The type of MCP assembly incorporated into a focal plane detector device depends on the required gain. However, within a single device, MCP assemblies with the same channel size and gain are typically used to maintain uniform detection efficiency and spatial resolution across the detector.

[0008] When a single channel in the first MCP layer is activated upon particle detection, it activates several channels in subsequent plates of the chevron assembly. In a Z-stack configuration, even more channels are activated in the third MCP. Thus, when a single particle is detected by the first MCP, the readout anode registers signals from several channels. Therefore, the spatial resolution of the MCP, especially in a stacked assembly, is limited by the number of MCP channels, which is typically in the range of a few micrometers to a few hundred micrometers. Increasing the gain of the detected signal reduces its spatial resolution.

[0009] MCP-based detectors are similarly useful in the field of optical beam analysis when used in conjunction with spectroscopic devices.

[0010] The resolution of a mass spectrometer provides a measure of the device's ability to separate two peaks with slightly different mass-to-charge ratios in the resulting mass spectrum. It is defined as R=m / Δm, where m is the mass number of the observed mass and Δm is the difference between the two separable masses. Mass separation translates to mass dispersion along the detection plane.

[0011] For a given magnetic sector mass spectrometer device, the higher the mass resolution, the finer the mass spectral lines (or beam widths) produced. As a result, for a given focal plane detector, the higher the mass resolution, the fewer detector pixels on the focal plane detector are covered by the spectral lines. For example, a spectral line produced by a given mass spectrometer device with a mass resolution of 400 may cover more than 10 detector pixels, while a spectral line produced by a mass spectrometer device with a mass resolution of 1200 may cover only four pixels. In the first case, the spectral line can be reconstructed by the intensity distribution along the covered pixels. In the latter case, the exact spectral line profile cannot be reconstructed because the number of individual pixels covered is limited, resulting in a detected peak width that is limited to at most two pixels larger than the actual peak width. Therefore, the mass resolution measured by the detector is lower than the actual mass resolution of the spectrometer. Considering the statistics of the number of pixels required to reconstruct a mass spectral line, and the typical pixel size of 50-100 μm for MCP-based detectors, focal plane detectors are only efficient for detecting mass spectral lines over a few hundred micrometers without significantly compromising mass resolution.

[0012] Mass accuracy indicates how accurate the mass value measured by the analyzer is compared to the actual mass value. Mass accuracy depends on several parameters, such as mass analyzer characteristics such as mass resolution, analyzer calibration, and electronics stability. In magnetic sector mass spectrometers with focal plane detectors, mass accuracy also depends on the spatial resolution or pixel size of the detector. As already discussed, because spectral lines are represented by current distributions across many individual pixels on the detector, the highest achievable accuracy of mass distribution is usually limited to the size of a single detector pixel, regardless of how accurate the other parameters mentioned above are.

[0013] Currently, no known devices offer charged particle detection that achieves high achievable mass resolution and mass accuracy in a magnetic sector analyzer device equipped with an MCP-based focal plane detector. The trade-offs outlined above inherently limit one or the other of the performance characteristics of any of the known solutions. Summary of the Invention [Problem to be solved by the invention]

[0014] It is an object of the present invention to provide a device and method that overcomes at least some of the drawbacks of the prior art. [Means for solving the problem]

[0015] According to a first aspect of the present invention, there is provided an analysis device for analyzing an incident charged particle or light beam. The analysis device comprises a filtering arrangement for producing a charged particle or light beam dispersed from the incident beam along a first direction X. The filtering arrangement further defines a focal plane extending in the first direction X and in a second direction Z perpendicular to the first direction. The device further comprises position sensitive charged particle or light detection means comprising a detection front extending downstream from and parallel to the focal plane.

[0016] The analysis device is advantageous in that at least one aperture plate is arranged on said focal plane, said at least one aperture plate comprising at least one high-resolution slit extending in said second direction Z for passing said dispersed charged particle beam or light beam at predetermined positions of said aperture plate along said first direction X, and displacement means for displacing the respective positions along said first direction X at which said dispersed charged particle beam or light beam arrives on the aperture plate.

[0017] Preferably, the displacement means may comprise mechanical or electromechanical means for displacing the position of said at least one aperture plate relative to the filtering device along said first direction X.

[0018] The displacement means may preferably comprise a piezoelectric element configured to selectively shift the position of the at least one aperture plate upon actuation. Alternatively, the displacement means may comprise a stepper motor element or an automated mechanical manipulator.

[0019] The device may preferably comprise an aperture plate holder located at the focal plane, the at least one aperture plate being removably coupled to the aperture plate holder.

[0020] Preferably, the aperture plate holder may be further configured to selectively hold said at least one aperture plate or said charged particle or light detection means.

[0021] The analysis device may preferably comprise a single aperture plate having a plurality of high-resolution slits along said first direction X.

[0022] Preferably, the analytical device may comprise a plurality of aperture plates, each aperture plate having at least one high-resolution slit.

[0023] Preferably, the aperture plate may comprise tungsten, platinum, molybdenum or stainless steel. For optical beam analysis applications, the aperture plate may preferably be provided with a low reflectivity coating.

[0024] The width of the high-resolution slit along the first direction X may preferably be within 50% to 80% of the spectral peak of the beam it filters. Preferably, the width of the high-resolution slit may be configured in the range between 5 and 100 micrometers.

[0025] The height of the high-resolution slit along the second direction Z may preferably be in the range of 2 to 10 mm. Preferably, the height of the slit may be chosen to be at least as large as the beam width in the Z direction.

[0026] Preferably, the detection means may be located at a distance of 2 to 10 mm downstream from said aperture plate and focal plane.

[0027] The analytical device may preferably further comprise biasing means arranged to apply a positive or negative floating potential to the aperture plate and to the detection means.

[0028] The filtering device may preferably comprise a magnetic sector device for dispersing the ion beam along said first direction X according to their mass-to-charge ratio.

[0029] The analytical device is preferably characterized by a location of elemental dispersion along its focal plane, and the high-resolution slit of said at least one aperture plate may preferably be positioned to coincide with at least a part of said location.

[0030] Preferably, the displacement means may comprise a control unit configured to selectively vary the strength of the magnetic field of the magnetic sector device in order to selectively shift the position of the exit point from which the dispersed ion beam exits the magnetic sector device.

[0031] The position sensitive charged particle detection means may preferably comprise a focal plane detector having a plurality of microchannel plate devices coupled to a readout anode. Preferably, the focal plane detector may extend along a distance of at least 10 to 30 cm.

[0032] According to another aspect of the present invention there is provided a mass spectrometer device comprising an ion source for producing an ion beam comprising ion species of a sample, the spectrometer being advantageous in that it further comprises an analysis device according to an aspect of the present invention.

[0033] Preferably, the mass spectrometer device may be configured such that the ion beam comprising ion species of a sample is filtered using the magnetic sector instrument, which disperses the ion species along the first direction X according to their mass-to-charge ratio before a corresponding dispersed ion beam reaches the aperture plate.

[0034] The mass spectrometer may preferably be configured for use in a floating configuration.

[0035] According to a further aspect of the invention, there is proposed a method for collecting high resolution spectral data of a sample using a mass spectrometer device according to an aspect of the invention.

[0036] Here's how: i) filtering an ion beam carrying ions from the sample by said analysis device to produce a set of ion beams dispersed along said first direction X according to their mass-to-charge ratio; ii) providing at least one aperture plate on the focal plane, said at least one aperture plate providing at least one high-resolution slit at an element dispersion position of the spectrometer; iii) using said displacement means to cause a displacement along a first direction X of a position of impingement of each of the filtered beams on said at least one aperture plate; iv) collecting position sensitive detection data of the ion beam reaching the ion detection means during said displacement. Includes:

[0037] Preferably, in step iii) the strength of the magnetic field in the ion path of the magnetic sector instrument of the analytical device is modified.

[0038] The present invention provides devices and methods that enable high mass resolution and high mass accuracy in magnetic sector mass spectrometers with focal planes that enable parallel detection of a wide range of ion species. According to some embodiments of the present invention, both continuous parallel detection of mass spectra with spectral lines limited to a few hundred micrometers (typically limited to a mass resolution of less than 1000) and parallel detection of a series of mass spectral lines with unlimited spectral width (achievable mass resolutions of several thousand) can be obtained. Embodiments of the present invention overcome the limitations on achieving high mass resolution and high mass accuracy in magnetic sector mass spectrometers equipped with focal plane detectors due to the limited spatial resolution of the focal plane detector. The disclosed concept is based on incorporating a series of narrow slits, preferably movable, into a focal plane detector system. The narrow slits function as mass filtering due to their width, while the focal plane detector can function as a signal readout for the slits or as a position-sensitive detector in its own right. In a preferred embodiment, the one or more plates carrying the slits and the focal plane detector are both mounted on a manipulation mechanism that allows them to be positioned in two configurations: either the focal plane detector is on the focal plane of the mass spectrometer and the slit is moved to a retracted position; or the aperture plate carrying the slit is located on the focal plane of the mass spectrometer and the focal plane detector is positioned behind the slit. In this case, both the series of slits and the focal plane detector are involved in the detection process.

[0039] In the first configuration, the detection system uses focal plane detectors for continuous, global parallel acquisition at its native spatial resolution. In the second configuration, at each slit, only a narrow portion of the spectral line passes through the slit and is detected by the focal plane detector, increasing the mass filtering resolution at the slit position. The achieved mass resolution is determined by the slit size and is therefore not limited by the physical constraint of the detector's spatial resolution. While the following description focuses on ion beam detection, the invention is equally useful for detecting other charged particle beams and light beams carrying light of various wavelengths that can be dispersed by optical systems including lenses and prisms: dispersed light beams can be detected using similar focal plane detectors including MCPs, and their resolution can be increased by the proposed invention.

[0040] Although some embodiments of the present invention are illustrated in the drawings, they are not intended to limit the scope of the invention. [Brief explanation of the drawings]

[0041] [Figure 1] 1 is a schematic top view of a section through an analytical device according to a preferred embodiment of the present invention; FIG. [Figure 2] 1 is a schematic top view of a cut plane through a spectrometer device according to a preferred embodiment of the present invention; [Figure 3] 1 is a workflow illustrating the main steps of a method according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0042] This section will further describe the features of the present invention based on preferred embodiments and figures, but the present invention is not limited to the described embodiments. Unless otherwise specified, features described in the context of a particular embodiment may be combined with additional features of other described embodiments. Similar reference numerals will be used to designate similar or identical concepts throughout the various embodiments. For example, the numerals 100 and 200 both designate analytical devices according to two respective embodiments of the present invention.

[0043] This description focuses on aspects that are important to an understanding of the invention. For example, it will be clear to one skilled in the art that a device for obtaining mass spectral data also comprises other commonly known aspects, such as an appropriately sized power supply, or a mechanical holder frame for holding the various elements of the device in their required positions, and this is true even if those aspects are not explicitly mentioned.

[0044] FIG. 1 shows a schematic top view of a section through an analytical device 100 according to an embodiment of the present invention. The device 100 comprises a filtering device 110, which generates from an input beam 01 a plurality of beams 101, 101' that exit the filtering device at positions along the exit surface of the filtering device. The beams 101, 101' are dispersed along a first direction X and typically extend in a plane parallel to the drawing plane. By way of example, the input beam 01 may be an ion beam carrying various ion species. In this case, the filtering device 110 may comprise, for example, a magnetic sector device, as known in the art of mass spectrometry. In the magnetic sector device, a gap extending parallel to the drawing plane allows the ion beam 01 to travel. When a magnetic field is applied through the gap, ion species with different mass-to-charge ratios are deflected with different amplitudes, resulting in the beams 101, 101' being dispersed along the first direction X according to the mass-to-charge ratios of the ion species they carry. Alternatively, the input beam 01 may be a light beam carrying light of multiple wavelengths, in which case the filtering device 110 may comprise, for example, an arrangement of optical lenses and prisms for splitting the different component wavelengths into beams 101, 101′ along the first direction X.

[0045] The filtering device 110 defines a focal plane 112 extending in a first direction X and in a second direction Z perpendicular to the first direction. The device 100 further comprises a position-sensitive charged particle or light detection means 130 having a detection front extending parallel to and downstream from the focal plane. Typically, the detector is positioned parallel to the focal plane at a distance of 2 to 10 mm from the focal plane. The detection front is the entrance face of the detector 130. In a preferred embodiment, the detection front comprises the entrance of a microchannel plate (MCP) device, which is preferably stacked in a chevron stack or Z-stack to increase the amplification gain. The detector 130 also preferably comprises a readout anode, which can be coupled to a computing device: charged particles (electrons, ions) or photons striking the detector front generate amplified signals along the X-axis at the output of the MCP assembly; these amplified signals, along with their position, are then detected on the readout anode. The corresponding data is stored in a memory element and can be used to construct the spectrum of the beam 01 being analyzed.

[0046] The analysis device 100 is distinguished by the fact that at least one aperture plate 120 is arranged on the focal plane 112. In the illustrated example, one aperture plate 120 comprises two high-resolution slits 122 extending in the second direction Z. If the beam 101′ reaches the aperture plate at the position of the slits 122, the beam 101′ passes through the slits and strikes the detector 130. If the beam 101 reaches the aperture plate between the slits, the beam or a corresponding part of the beam width is blocked. The slits 122 allow the dispersed charged particle beam or the light beam to pass through the aperture plate at a predetermined position of the aperture plate along the first direction X. Furthermore, the device 100 comprises displacement means 140 for displacing the respective position along the first direction X at which the dispersed charged particle beam or the light beam reaches the aperture plate. By way of example: in the illustrated situation, the beam 101 strikes the aperture plate at a position P between two slits 122. The position P can be changed either by making the beam 101 follow a different trajectory or by shifting the position of the aperture plate 120 along the first direction X. Thus, if the position at which the same beam 101 strikes the plane of the aperture plate is changed, the beam 101 may pass through one of the slits 122.

[0047] Preferably, the displacement may comprise mechanical or electromechanical means, for example a piezo element or a step motor, for displacing the position of said at least one aperture plate relative to the filtering device along said first direction X.

[0048] By displacing the slit 122 (or the beam 101, 101') during signal acquisition at the detector 130, the beam dispersion shape is convolved with the width of the slit and the detected signal is effectively a filtered version of the beam dispersion profile. A slit with a width (or diameter) smaller than the beam width is used to select a portion of the beam to be recorded by a detector placed downstream from the slit.

[0049] Two protocols can be used to record the beam profile, i.e., the spectral peaks associated with the detected charged particle or light beam: either the slit is displaced or the beam is swept across the slit. In either scenario, the signal response recorded by the detector can be expressed by the convolution of the ion beam profile and the slit (sometimes called the slit's response function). This signal response represents the ion profile (or spectral peaks) recorded by the detector. In applications contemplated by the present invention, a slit width of 50-80% of the beam profile generated by the filtering device 110 is typically used, so that the detected spectral profile remains close to the intrinsic peaks and has a good signal-to-noise ratio (SNR). The use of a slit increases the instrument's high-resolution capability. Therefore, the slit 122 is also referred to as a high-resolution slit, or in the case of ion beams, a high-mass resolving power slit. In particular, when combined with an MCP focal plane detector, high ion counts can be achieved during parallel acquisition of a complete spectrum with high mass resolution, providing advantages over known devices.

[0050] The use of aperture plate 120 having a slit at a given position along first direction X increases the resolution of the detection system at that position. Thus, an aperture plate can be selectively placed within a portion of the detection area along the first direction X to record a corresponding portion of the spectrum with high resolution, while the remaining portion of the spectrum where the aperture plate is not present is simultaneously recorded with lower resolution. In practice, detector 130 is located downstream from the focal plane and can therefore be considered out of focus for beams not scanned through the high-resolution slit. This mode of operation is sometimes referred to as a “hybrid” mode because, simultaneously with recording, one or more regions of interest in the spectrum of beam 01 can be recorded with higher resolution than other regions of the spectrum. Thus, device 100 can include either a single aperture plate having multiple high-resolution slits along the first direction, or multiple such plates, each having at least one such high-resolution slit.

[0051] A mechanical holder structure (not shown) can be used to removably receive at least one aperture plate on the focal plane. In a preferred embodiment, the holder can be designed to be able to receive either the aperture plate or the focal plane detector 130. This allows for increased flexibility of the device: when there is no spectral region of greater interest, the focal plane detector 130 can be moved into the holder and positioned above the focal plane of the analytical device. This configuration allows for global parallel acquisition of spectral information.

[0052] If an area is of greater interest, the focal plane detector is removed from the holder and placed at a distance downstream from the focal plane, while the aperture plate 120 is placed on the focal plane by the holder. The detector 130 then serves as a readout of the signal filtered by the slit 122 due to the relative displacement of the beams 101, 101' with respect to the slit.

[0053] The detection means and aperture plate may preferably be floated to a high voltage of up to 10 kV, where the floating potential may have either a positive or negative polarity. Electrical biasing means may be operatively connected to the detection means and aperture plate to provide these potentials as required.

[0054] 2 shows a preferred embodiment of an analytical device 200 according to the invention. A source 10 of ions provides an ion beam carrying ion species extracted from a sample, as known in the art. The device 10 may, for example, comprise an ion extraction device and a sector instrument for focusing the beam 01 before it reaches the analytical device 200. Together with the source 10 of ions, the analytical device 200 forms a spectrometer.

[0055] The device 200 includes a filtering device 210, which is a magnetic sector device. From an input ion beam 01, the magnetic sector device 210 generates multiple ion beams 201 that exit the magnetic sector device at various positions along its exit surface. The ion beams 201 are dispersed along a first direction X, typically extending in a plane parallel to the drawing plane of the figure. Within the magnetic sector device, a gap extending parallel to the drawing plane allows the ion beam 01 to travel. When a magnetic field is applied through the gap, ion species with different mass-to-charge ratios are deflected with different amplitudes, resulting in the beam 201 being dispersed along the first direction X according to the mass-to-charge ratios of the ion species they carry.

[0056] The magnetic sector device 210 defines a focal plane 212 extending in a first direction X and in a second direction Z perpendicular to the first direction. The device 200 further comprises a position-sensitive charged particle detector 230 having a detector front extending parallel to and downstream from the focal plane. Typically, the detector is positioned parallel to the focal plane at a distance of 2 to 10 mm from the focal plane. The detector front is the entrance face of the detector 230. The detector front comprises the entrance of a microchannel plate (MCP) device, which is preferably stacked in a chevron stack or Z-stack to increase the amplification gain. The detector 230 also comprises a readout anode, which can be coupled to a computing device: ion species striking the detector front generate amplified signals along the X-axis at the output of the MCP assembly; these amplified signals, together with their positions, are then detected on the readout anode. Corresponding data can be stored in a memory element and used to construct the spectrum of the analyzed ion beam 01.

[0057] The analysis device 200 is advantageous in that an aperture plate 220 is arranged on the focal plane 212, held in place by a mechanical holder device 250. As explained in the context of the previous embodiment, the holder 250 can preferably alternatively hold the detector 130. In the example shown, one aperture plate 220 comprises a series of high mass resolution slits 222 extending in the second direction Z. The positions of the high mass resolution slits along the focal plane detector are chosen to coincide with the location of the elemental dispersion of the mass spectrometer along its focal plane. A typical example of the mass dispersion characteristic of a Mattauf-Herzog mass spectrometer is expressed as a square root function of mass. In this case, the slit positions can be defined as follows:

number

[0058] In particular, the device 200 comprises a control unit 240 operatively coupled to an electromagnet generating a magnetic field in the gap space of the magnetic sector device 210. The control unit may comprise an integrated circuit or a suitably programmed computer chip. This, together with the electromagnet, constitutes an implementation of the displacement means: varying the magnetic field within a small range slightly modifies the exit point at which the ion beam 201 exits the magnetic sector device 210, which allows for rapid and accurate parallel scanning of the ion beam 201 across multiple slits 222 in the aperture plate 212. While the operating principle remains the same as in the previously described embodiment, this configuration has the advantage of not relying on mechanical parts and of allowing for the recording of the entire mass spectrum of the ion beam 201 in parallel with high mass resolution and mass accuracy.

[0059] FIG. 3 illustrates the main steps of the spectral acquisition that have been described in the context of an embodiment of the disclosed analytical device.

[0060] In a first step i), an ion beam carrying ions from a sample is filtered by an analysis device according to an embodiment of the present invention to generate a set of ion beams dispersed along a first direction X according to their mass-to-charge ratio. In step ii), at least one aperture plate in the focal plane is filtered, said at least one aperture plate providing at least one high-resolution slit at the element dispersion position of the analyzer. This step can of course be performed in parallel with step i) or before step i). In step iii), said displacement means is used to cause a displacement along the first direction X of the impact location of each of the filtered beams on said at least one aperture plate. Finally, during said displacement, position-sensitive detection of data of the ion beams reaching the ion detection means is performed, resulting in parallel acquisition of high-resolution spectral data.

[0061] It will be understood that the detailed description of certain preferred embodiments is given by way of example only, since various changes and modifications within the scope of the present invention will be apparent to those skilled in the art. The scope of protection is defined by the following set of claims.

Claims

1. An analyzing device (100, 200) for analyzing an incident charged particle beam or light beam (01), comprising: a filtering device (110, 210) for producing from the incident beam (01) a charged particle beam or light beam (101, 101′, 201) dispersed along a first direction X, the filtering device (110, 210) further defining a focal plane (112, 212) extending in the first direction X and in a second direction Z perpendicular to the first direction; a position-sensitive charged particle or light detection means (130, 230) having a detection front surface extending downstream from and parallel to said focal plane (112, 212); Equipped with an analyzing device (100, 200) characterized in that at least one aperture plate (120, 220) is arranged on the focal plane (112, 212), the aperture plate comprising at least one high-resolution slit (122, 222) extending in the second direction Z for passing the dispersed charged particle beam or light beam (101, 101', 201) at a predetermined position of the aperture plate (120, 220) along the first direction X; and a displacement means (140, 240) for displacing a respective position (P) along the first direction X at which the dispersed charged particle beam or light beam (101, 101', 201) arrives on the aperture plate (120, 220).

2. 2. The analytical device of claim 1, wherein the displacement means (140) comprises mechanical or electromechanical means for displacing the position of the at least one aperture plate (120) relative to the filtering apparatus (110) along the first direction X.

3. 3. The analysis device of claim 1, further comprising an aperture plate holder (250) disposed in the focal plane (212), wherein the at least one aperture plate (220) is removably coupled to the aperture plate holder.

4. 5. The analytical device of claim 4, wherein an aperture plate holder (250) is further configured to selectively hold the at least one aperture plate (220) or the charged particle or light detection means (230).

5. 5. An analytical device according to any one of claims 1 to 4, comprising a single aperture plate having a plurality of high-resolution slits along said first direction X.

6. 5. An analytical device according to any one of claims 1 to 4, comprising a plurality of aperture plates, each aperture plate having at least one high-resolution slit.

7. 7. The analytical device according to any one of claims 1 to 6, wherein the detection means (130, 230) are arranged at a distance of 2 to 10 mm downstream from the aperture plate (120, 220) and focal plane (112, 212).

8. 8. An assay device according to any one of claims 1 to 7, further comprising biasing means configured to apply a positive or negative floating potential to the aperture plate and to the detection means.

9. 9. The analytical device (200) according to any one of claims 1 to 8, wherein the filtering device comprises a magnetic sector device (210) for dispersing the ion beam (201) along the first direction X according to their mass-to-charge ratio.

10. 10. The analytical device (200) of claim 9, wherein the device is characterized by a location of elemental dispersion along its focal plane (212), and the high-resolution slit (222) of the at least one aperture plate (220) is positioned to coincide with at least a portion of the location.

11. 11. The analytical device (200) of claim 9 or 10, wherein the displacement means (240) comprises a control unit configured to selectively change the strength of the magnetic field of the magnetic sector device (210) in order to selectively shift the position of the exit point from which the dispersed ion beam (201) exits the magnetic sector device.

12. 12. An analytical device (200) according to any one of claims 9 to 11, wherein the position sensitive charged particle detection means (230) comprises a focal plane detector having a plurality of microchannel plate devices coupled to a readout anode.

13. 13. A mass spectrometer device comprising an ion source (10) for producing an incident ion beam (01) comprising ion species of a sample, characterized in that it further comprises an analysis device (200) according to any one of claims 9 to 12.

14. 14. The mass spectrometer device of claim 13, wherein the ion beam (01) containing ion species of a sample is filtered using the magnetic sector device (210), which disperses the ion species along the first direction X according to their mass-to-charge ratio before a corresponding dispersed ion beam (201) reaches the aperture plate (220).

15. 15. A method for collecting high resolution spectral data of a sample using a mass spectrometer device according to claim 13 or 14, comprising the steps of: i) filtering an ion beam carrying ions from the sample by said analysis device to produce a set of ion beams dispersed along said first direction X according to their mass-to-charge ratio; ii) providing at least one aperture plate on the focal plane, said at least one aperture plate providing at least one high resolution slit at the element dispersion position of the spectrometer; iii) using said displacement means to cause a displacement along a first direction X of the position of impingement of each of the filtered beams on said at least one aperture plate; iv) collecting position sensitive detection data of the ion beam reaching the ion detection means during said displacement. A method comprising:

16. 16. The method of claim 15, wherein in step iii) the strength of the magnetic field in the ion path of the magnetic sector instrument of the analytical device is changed.

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