Methods and apparatus for trapping and accumulation of ions

Abstract

To provide additional systems and methods for internal ion trapping and accumulation to enhance resolution and sensitivity within IMS and MS systems.SOLUTION: An apparatus for ion accumulation includes multiple regions. A first region receives and transfers ions to a second region using a first drive potential. The second region is switchable between a first state where it generates a first electric field preventing ions from further movement and entering a third region, and a second state where it generates a second electric field that guides the ions toward the third region. When in the first state, the ions are prevented from further movement by the first electric field, which causes the ions to accumulate in the second region. When in the second state, the ions are moved from the second region to the third region by the second electric field. A method of accumulating ions involves switching an electric field applied to a region between a trap state and a release state.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 028,768, filed May 22, 2020, which is hereby incorporated by reference in its entirety.

[0002] The present disclosure generally relates to the fields of ion mobility spectrometry (IMS) and mass spectrometry (MS). More particularly, the present disclosure relates to methods and apparatuses for the capture and accumulation of ions to increase the resolution of ions in IMS and MS systems.

Background Art

[0003] IMS is a technique for separating and identifying ions in the gas phase based on their mobility. For example, IMS can be used to separate structural isomers and macromolecules with different mobilities. IMS relies on applying a constant or time - varying electric field to a mixture of ions in a static or dynamic background gas. Ions with a larger mobility (or a smaller collision cross - section [CCS]) move faster under the influence of the electric field compared to ions with a smaller mobility (or a larger CCS). By applying an electric field across the separation distance (e.g., within a drift tube) of an IMS device, ions from an ion mixture can be separated temporally or spatially based on their mobility. Since ions with different mobilities reach the end of the drift tube at different times (temporal separation), these ions can be identified based on the detection times by a detector located at the end of the drift tube. The resolution of mobility separation can be changed by varying the separation distance.

[0004] MS is an analytical technique capable of separating a mixture of chemical species based on their mass-to-charge ratio. MS involves ionizing a mixture of chemical species, followed by accelerating the ion mixture in the presence of an electric field and / or a magnetic field. In some mass spectrometers, ions with the same mass-to-charge ratio receive the same deflection or time-dependent response. Ions with different mass-to-charge ratios may receive different deflections or time-dependent responses and can be identified based on the spatial or temporal position of detection by a detector (e.g., an electron multiplier tube).

[0005] Combining IMS and MS can generate an IMS-MS spectrum that can be used in a wide range of applications, including metabonomics, glycomics, and proteomics. IMS-MS ion separation can be performed by connecting an ion mobility analyzer to a mass spectrometer. For example, an ion mobility analyzer can first separate ions based on their mobility. Ions with different mobilities can reach the mass spectrometer at different times and are then separated based on their mass-to-charge ratio. An example of an IM analyzer is a structure for a lossless ion manipulation (SLIM) device that can generate an IMS spectrum with minimal ion loss. The SLIM device can use traveling wave separation as one technique for separating ions of different mobilities. However, in traveling wave separation, as in ion mobility separation, especially when traveling wave separation is performed over a long distance, the peaks can broaden.

[0006] Furthermore, the signal-to-noise ratio and resolution at detection are affected by the number of ions introduced into the IMS device. Accordingly, ion traps have been used to accumulate ions before injecting them for ion mobility separation, but such ion traps is limited by the space charge effect. In this regard, an ion trap can accumulate a limited number of charges before reaching the space charge capacity where ions can potentially be lost from the trap. In the past, these limitations have typically been addressed by increasing the path length, which can result in the device being larger and / or more complex. Additionally, systems and methods have been developed that provide intermittent or "choppy" traveling waves to classify, compress, or regroup ions into a reduced number of ion mobility bins, resulting in spatial compression of the ions and increased resolution of the ion packets in IMS. For example, Patent Document 1 named "Method and Apparatus for Spatial Compression and Increased Mobility Resolution of Ions" discloses changing the duty cycle of an intermittent traveling wave to compress ion packets into narrower distribution peaks. However, the above methodologies are still limited by the space charge effect and parameters (such as velocity, amplitude, waveform, etc.) of the traveling wave utilized.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] Accordingly, there is a need for additional systems and methods for internal trapping and accumulation of ions to increase resolution and sensitivity within IMS and MS systems.

Means for Solving the Problems

[0009] The present disclosure relates to methods and apparatuses for internal trapping and accumulation of ions to increase the resolution of ions within IMS and MS systems.

[0010] According to an embodiment of the present disclosure, an exemplary apparatus for ion accumulation is provided. The apparatus for ion accumulation includes a first region and a second region. The first region is configured to receive ions and generate a first driving potential configured to guide the ions in a first direction across the first region. The second region is configured to receive ions from the first region and switch between a first state in which the ions can be in a trapped state and a second state in which the ions can be in a released state, generate a first electric field when in the first state, and generate a second electric field when in the second state. The first electric field is configured to prevent the ions from moving in the first direction and entering a third region, and the second electric field is configured to guide the ions in the first direction toward the third region. Accordingly, the first electric field can be generated during the trapped state, and the second electric field can be generated during the released state. When the second region is in the first state, the first driving potential and the first electric field prevent the ions in the second region from exiting the second region and accumulate the ions within the second region. When the second region is in the second state, the second electric field moves the ions in the first direction toward the third region.

[0011] In one aspect, the first driving potential can be a traveling wave. In another aspect, the first electric field can be a DC voltage. In such an aspect, the magnitude of the DC voltage can be made greater than the voltage bias of the first driving potential. Additionally, in such an aspect, the second electric field can be a traveling wave, and the traveling wave can be configured to separate the ions based on mobility. In other aspects, the magnitude of the DC voltage can be made less than the voltage bias of the first driving potential, and the DC voltage can create a potential well. In such an aspect, the second electric field can be a DC potential gradient or a traveling wave configured to separate the ions based on mobility.

[0012] In some embodiments, the first electric field can be a traveling wave that travels in a second direction opposite to the first direction, and the second electric field can be a second traveling wave that travels in the first direction. In such embodiments, the second traveling wave can be configured to separate ions based on mobility. Additionally, in such embodiments, the first electric field can be generated during the capture state, and the second electric field can be generated during the release state.

[0013] In other embodiments, the third region can be configured to receive ions from the second region and generate a second driving potential configured to separate the ions based on mobility.

[0014] In yet other embodiments, the first region can include a plurality of electrodes disposed on the first surface and arranged along the first direction and configured to generate a first driving potential, the second region can include one or more electrodes disposed on the first surface and arranged along the first direction, and at least one of the one or more electrodes in the second region can be configured to generate a first electric field when in the first state and a second electric field when in the second state.

[0015] In such an embodiment, the apparatus can include a controller configured to apply a first voltage signal to a plurality of electrodes in a first region, apply a second voltage signal to at least one of one or more electrodes in a second region, and apply a third voltage signal to at least one of one or more electrodes in the second region. Additionally, the plurality of electrodes can be configured to generate a first driving potential based on the first voltage signal, at least one electrode can be configured to generate a first electric field based on the second voltage signal, and at least one electrode can be configured to generate a second electric field based on the third voltage signal. When the apparatus is in a first operating mode, the controller applies the second voltage signal to a second plurality of electrodes to put the second region in a first state, and when the apparatus is in a second operating mode, the controller applies the third voltage signal to the second plurality of electrodes to put the second region in a second state.

[0016] In some embodiments, a first portion of the second region can generate a first electric field when the second region is in the first state, the first portion of the second region can generate a second electric field when the second region is in the second state, and a second portion of the second region can generate a fourth electric field different from the first electric field.

[0017] In some other embodiments, the second region can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, and each of the plurality of TW electrode arrays can include at least three individual electrodes. In such an embodiment, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

[0018] A method for ion accumulation involves introducing ions into an apparatus for ion accumulation having a first region, a second region, and a third region. The method includes generating a driving potential within the first region to guide ions in a first direction across the first region, and transmitting ions from the first region to the second region by the driving potential. The method also includes generating a first electric field within the second region to prevent ions from moving in the first direction and entering the third region, and accumulating ions within the second region. The first electric field can be applied during the trapping state. The method further includes switching the first electric field generated within the second region to a second electric field to guide the accumulated ions in the first direction towards the third region. The second electric field can be generated during the release state.

[0019] In some embodiments, the driving potential can be a traveling wave. In other embodiments, the first electric field can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be made greater than the voltage bias of the driving potential. In other such embodiments, the second electric field can be a traveling wave, and the method can involve separating ions based on mobility by the traveling wave.

[0020] In other embodiments, the magnitude of the DC voltage can be made less than the voltage bias of the first driving potential, and the DC voltage can create an electric potential well. In such embodiments, the second electric field can be a DC potential gradient or a traveling wave. When the second electric field is a traveling wave, the method can further involve separating ions based on mobility by the traveling wave.

[0021] In yet other embodiments, the first electric field can be a first traveling wave traveling in a second direction opposite to the first direction, and the second electric field can be a second traveling wave traveling in the first direction. In such embodiments, the method can further involve separating ions based on mobility by the traveling waves. Additionally, in such embodiments, the first electric field can be generated during the trapping state, and the second electric field can be generated during the release state.

[0022] In one aspect, the method can also involve transferring ions accumulated in a second region to a third region, generating a second drive potential in the third region, and separating the ions based on mobility by the second drive potential.

[0023] In some aspects, a first portion of the second region can generate a first electric field and a second electric field, and a second portion of the second region can generate a fourth electric field different from the first electric field.

[0024] In some other aspects, the second region can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, and each of the plurality of TW electrode arrays can include at least three individual electrodes. In such aspects, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in a first state.

[0025] In another aspect, an apparatus for ion accumulation includes an ion channel, a first region, a second region, a third region, and a controller. The ion channel is defined between a first surface and a second surface, extends along a first longitudinal direction and a first transverse direction, and is configured to receive a flow of ions. The first region includes a plurality of electrodes disposed on the first surface and arranged along the first longitudinal direction. The second region includes one or more electrodes disposed on the first surface and arranged along the first longitudinal direction. The controller is configured to apply a first voltage signal to the plurality of electrodes of the first region, apply a second voltage signal to the one or more electrodes of the second region, and apply a third voltage signal to the one or more electrodes of the second region. The second voltage signal can be applied during a capture operation mode, and the third voltage signal can be applied during a release operation mode. The plurality of electrodes of the first region are configured to generate a first driving potential that progresses along the first longitudinal direction based on the first voltage signal. The first driving potential is configured to guide ions in the first longitudinal direction across the ion channel. The one or more electrodes of the second region are configured to generate a first electric field that prevents ions from progressing into the third region along the first longitudinal direction based on the second voltage signal. The first electric field can be generated during the capture operation mode. The one or more electrodes of the second region are configured to generate a second electric field that guides ions toward the third region along the first longitudinal direction based on the third voltage signal. The third voltage signal can be generated during the release operation mode. When the device is in a first operation mode in which it can be in a capture operation mode, the controller applies a second voltage signal to the one or more electrodes of the second region, and the first driving potential and the first electric field prevent ions in the second region from exiting the second region, thereby accumulating ions in the second region. When the device is in a second operation mode in which it can be in a release operation mode, the controller applies a third voltage signal to the one or more electrodes of the second region, and the second electric field moves the ions toward the third region in a first direction. When the device is in a first operation mode in which it can be in a capture operation mode, the controller applies a second voltage signal to the one or more electrodes of the second region, and the first driving potential and the first electric field prevent ions in the second region from exiting the second region, thereby accumulating ions in the second region. When the device is in a second operation mode in which it can be in a release operation mode, the controller applies a third voltage signal to the one or more electrodes of the second region, and the second electric field moves the ions toward the third region in a first direction.

[0026] In some embodiments, the first voltage signal can be a traveling wave. In other embodiments, the second voltage signal can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be made greater than the voltage bias of the first drive potential. Also in such embodiments, the third voltage signal can be a traveling wave, and the traveling wave can be configured to separate ions based on mobility.

[0027] In other embodiments, the second voltage signal can be applied to a single electrode in the second region.

[0028] In still other embodiments, the magnitude of the DC voltage can be made less than the voltage bias of the first drive potential, and the DC voltage can create a potential well. In such embodiments, the third voltage signal can be a DC potential gradient or a traveling wave configured to separate ions based on mobility. In such embodiments, the DC voltage can be applied to two or more electrodes in the second region.

[0029] In one embodiment, the second voltage signal can be a traveling wave traveling in a second direction opposite to the first direction, and the third voltage signal can be a second traveling wave traveling in the first direction. In such embodiments, the second traveling wave can be configured to separate ions based on mobility. Additionally, in such embodiments, the second voltage signal can be applied during a capture operation mode, and the third voltage signal can be applied during a release operation mode.

[0030] In another embodiment, the third region can include a plurality of electrodes disposed on a first surface and arranged along a first longitudinal direction. The third region can be configured to receive ions from the second region and generate a second drive potential configured to separate the ions based on mobility.

[0031] A method for ion accumulation involves introducing an ion flow into an ion channel of an ion accumulation device. The accumulation device includes a first surface, a second surface, a first region disposed on the first surface and including a plurality of electrodes arranged along a first longitudinal direction, a second region disposed on the first surface and including one or more electrodes arranged along the first longitudinal direction, and a third region. The first ion channel is defined between the first surface and the second surface and extends along the first longitudinal direction and a first transverse direction. The method also includes applying, by a controller, a first voltage signal to the plurality of electrodes of the first region, and generating, by the plurality of electrodes of the first region, a first driving potential that progresses along the first longitudinal direction. The first driving potential is also configured to guide ions in the ion channel along the first longitudinal direction. The method also includes transmitting, by the first driving potential, ions in the ion channel from the first region to the second region along the first longitudinal direction. The method further includes applying, by the controller, a second voltage signal to the one or more electrodes of the second region, and generating, by the one or more electrodes of the second region, a first electric field based on the second voltage signal. During a capture operation mode, the second voltage signal can be applied and the first electric field can be generated. The method also includes preventing, by the first electric field, ions from moving in a first direction and entering the third region, and accumulating ions within the second region. The method includes switching, by the controller, the second voltage signal applied to the second region to a third voltage signal to guide the ions accumulated within the second region in the first direction towards the third region within the ion channel. During a release operation mode, the third voltage signal can be applied and the second electric field can be generated. This further includes guiding the ions accumulated within the second region in the first direction towards the third region within the ion channel. During a release operation mode, the third voltage signal can be applied and the second electric field can be generated.

[0032] In some embodiments, the first voltage signal can be a traveling wave. In other embodiments, the second voltage signal can be a DC voltage. In such embodiments, the magnitude of the DC voltage can be made greater than the voltage bias of the first voltage signal. In other such embodiments, the third voltage signal can be a traveling wave, and this method can involve separating ions based on mobility by the traveling wave. In yet other such embodiments, the second voltage signal can be applied to a single electrode in the second region.

[0033] In other embodiments, the magnitude of the DC voltage can be made less than the voltage bias of the first voltage signal, and the DC voltage can create a potential well. In such embodiments, the third voltage signal can be a DC potential gradient or a traveling wave. When the third voltage signal is a traveling wave, this method can further involve separating ions based on mobility by the traveling wave. In such embodiments, the DC voltage can be applied to two or more electrodes in the second region.

[0034] In yet other embodiments, the second voltage signal can be a traveling wave traveling in a second direction opposite to the first direction, and the third voltage signal can be a second traveling wave traveling in the first direction. In such embodiments, this method can further involve separating ions based on mobility by the traveling wave. Additionally, in such embodiments, the second voltage signal can be applied during a capture operation mode, and the third voltage signal can be applied during a release operation mode.

[0035] In one aspect, this method can also involve transferring ions accumulated in a second region to a third region. This method can also involve applying a fourth voltage signal to a plurality of electrodes in the third region by a controller, where the plurality of electrodes in the third region can be disposed on a first surface and arranged along a first longitudinal direction. This method can further involve generating a second driving potential that travels along the first longitudinal direction by the plurality of electrodes in the third region. The second driving potential can be configured to guide ions in the ion channel in the first longitudinal direction. This method can also involve separating ions based on mobility by the second driving potential. In some aspects, the fourth voltage signal and the third voltage signal can be the same. In other aspects, the first voltage signal, the third voltage signal, and the fourth voltage signal can be the same.

[0036] The ion accumulation device includes an ion accumulation section, an exit section, and an exit transition section. The ion accumulation section has a first width, receives ions, switches between a first state and a second state, generates a first electric field when in the first state, and generates a second electric field when in the second state. The exit section has a second width smaller than the first width and is configured to generate a third electric field configured to guide ions across the exit section. The exit transition section extends between the ion accumulation section and the exit section and has a tapered width that narrows from the first width adjacent to the ion accumulation section to the second width adjacent to the exit section. The exit transition section is also configured to generate a third electric field to guide ions across the exit transition section to the exit section. The first electric field is configured to prevent ions from moving in a first direction and entering the exit transition section, and the second electric field is configured to guide ions in the first direction toward the exit transition section. When the ion accumulation section is in the first state, the first electric field causes the ions in the ion accumulation section to accumulate Prevent ions from exiting the accumulation section and accumulate the ions within the ion accumulation section. When the ion accumulation section is in the second state, the second electric field moves the ions in the first direction towards the exit transition section.

[0037] In some embodiments, the exit transition section can be configured to prevent ions from being emitted due to the space charge effect. In some other embodiments, the third electric field can be the same as the second electric field or can be different from the second electric field.

[0038] In yet other embodiments, the ion accumulation device can also include an inlet section and an inlet transition section. The inlet section can have a third width smaller than the first width, and the inlet transition section can extend between the inlet section and the ion accumulation section. The inlet transition section can have a tapered width that increases from the third width adjacent to the inlet section to the first width adjacent to the ion accumulation section. In such embodiments, the inlet section and the exit transition section can be configured to generate a fourth electric field to guide ions across the inlet section and the inlet transition section and into the ion accumulation section.

[0039] In some other embodiments, the second electric field can be a traveling wave traveling in the first direction, and the ion accumulation section can be switched from generating the second electric field to generating a fourth electric field that is a traveling wave traveling in a second direction opposite to the first direction.

[0040] In other embodiments, the first electric field can be a DC voltage. In such embodiments, the first portion of the ion accumulation section can generate the first electric field, and the second portion of the ion accumulation section can generate a fourth electric field different from the first electric field.

[0041] In yet other embodiments, the ion accumulation section can include a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, and each of the plurality of TW electrode arrays includes at least three individual electrodes. In such embodiments, the first electric field can be generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays.

[0042] In other embodiments, the ion accumulation device can include an inlet section located alongside the ion accumulation section, and the inlet section is configured to provide ions to the ion accumulation section.

[0043] Other configurations will become apparent from considering the following detailed description in conjunction with the accompanying drawings. However, it should be understood that these drawings are not intended to define limitations of the invention, but are designed for illustrative purposes only.

[0044] The above-described configurations of the present disclosure are apparent from the following detailed description of the invention in relation to the accompanying drawings.

Brief Description of the Drawings

[0045]

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[0046] The present disclosure relates to methods and apparatus for internal capture and accumulation of ions, which will be described in detail below in connection with FIGS. 1-11.

[0047] Through ion mobility spectrometry (IMS), ions can be separated based on their mobility. Mobility separation can be achieved, for example, by applying one or more potential waveforms (e.g., traveling potential waveforms, direct current (DC) gradients, or both) to a group of ions. Mobility separation based on IMS can be achieved by a structure for lossless ion manipulation (SLIM) that can systematically apply traveling and / or DC potential waveforms to a group of ions, such as the devices disclosed and described in U.S. Patent No. 8,835,839, entitled "Method and Apparatus for Ion Mobility Separations Utilizing Alternating Current Waveforms," and U.S. Patent No. 10,317,364, entitled "Ion Manipulation Device," both of which are incorporated herein by reference in their entirety. As a result, a continuous stream of ions can be temporally / spatially separated based on their mobility. In some implementations, it is desirable to select ions having a predetermined mobility range from a group of ions. This can be achieved by filtering based on the mobility of ions within the SLIM device ("SLIM filter"). The SLIM filter (e.g., low-pass filter, high-pass filter, band-pass filter, etc.) can apply superpositions to a plurality of potential waveforms induced (e.g., traveling) in different directions (e.g., two-dimensional). The characteristics of the potential waveforms (e.g., amplitude, shape, frequency, etc.) can determine the characteristics of the SLIM filter (e.g., bandwidth, cutoff mobility value, etc.).

[0048] The present disclosure utilizes the SLIM device described above to not only transfer and separate ions of different mobilities but also accumulate ions within each SLIM device for subsequent separation and analysis. In this regard, as discussed in more detail below, different waveforms can be applied to different regions of the SLIM device, such as one or more electrodes grouped together, until the space charge limit is reached or a sufficient number of ions are accumulated, to capture ions within the accumulation region.

[0049] FIG. 1 is a schematic diagram of an exemplary ion mobility separation (IMS) system 100 according to the present disclosure. The IMS system 100 includes an ionization source 102, a SLIM device 104, a mass spectrometer 106, a controller 108, a computing device 110, a power supply 112, and a vacuum system 114. The ionization source 102 generates ions (e.g., ions having varying mobilities and mass-to-charge ratios) and injects the ions into the SLIM device 104 (discussed in more detail in connection with FIGS. 2-4). The SLIM device 104 can be configured to transmit, accumulate, store, and / or separate ions according to the desired function and the applied waveform. In this regard, the SLIM device 104 can be used to select ions having one or more predetermined mobility ranges and direct the selected ion band(s) to a detector, such as the mass spectrometer 106. The vacuum system 114 is in fluid communication with the SLIM device 104 and can regulate the gas pressure within the SLIM device 104. Specifically, the vacuum system 114 can maintain the pressure within the SLIM device 104 at a consistent pressure while providing nitrogen to the SLIM device 104.

[0050] The SLIM device 104 can include one or more surfaces 114a, 114b (e.g., printed circuit board surfaces), and a plurality of electrodes can be disposed on the one or more surfaces 114a, 114b. These electrodes can receive voltage signals, voltage waveforms, and / or current waveforms (e.g., DC voltage or current, RF voltage or current, or AC voltage or current, or a superposition thereof), as discussed in more detail below, and generate an electric potential (e.g., an electric potential gradient) to confine ions within the SLIM device 104, accumulate ions within the SLIM device 104, and guide ions through the SLIM device 104, such that the ions can be accumulated and separated based on their mobilities.

[0051] The controller 108 can control the operations of the ionization source 102, the SLIM device 104, the mass spectrometer 106, and the vacuum system 114. For example, the controller 108 can control the ion injection rate from the ionization source 102 into the SLIM device 104, the threshold mobility of the SLIM device 104, and the ion detection by the mass spectrometer 106. The controller 108 can also control the characteristics and movement of the potential waveform generated by the SLIM device 104 for transmitting, accumulating, and / or separating ions (e.g., by applying RF / AC / DC potentials to the electrodes of the SLIM device 104).

[0052] The controller 108 can control the characteristics of the potential waveform (e.g., amplitude, shape, frequency, etc.) by varying the characteristics of the applied RF / AC / DC potential (or current). In this regard, the controller 108 can vary the characteristics of the potential waveform for different regions of the SLIM device 104, such as different groups of electrodes, to capture / accumulate ions and later separate the ions. This can be done to increase the ion peak resolution, narrow the ion peak, increase the signal-to-noise ratio, and achieve sharp separation before and after the target mobility.

[0053] The controller 108 can receive power from the power supply 112, and the power supply 112 can be, for example, a DC power supply that provides a DC voltage to the controller 108. The controller 108 can include a plurality of power supply modules (e.g., current and / or voltage supply circuits) that generate various voltage (or current) signals for driving the electrodes of the SLIM device 104. For example, the controller 108 can include an RF control circuit that generates an RF voltage signal, a traveling wave control circuit that generates a traveling wave voltage signal, a DC control circuit that generates a DC voltage signal, and the like. The RF voltage signal, the traveling wave voltage signal, and the DC voltage signal can be applied to the electrodes of the SLIM device 104. The controller 108 can also include a master control circuit that can control the operation of the RF / traveling wave / DC control circuits. For example, the master control circuit can adjust the amplitude and / or phase of the voltage (or current) signals generated by the RF / traveling wave / DC control circuits to achieve the desired operation of the mobility filter system 100.

[0054] As discussed above, the SLIM device 104 can generate a DC / traveling potential waveform (e.g., resulting from the potential generated by a plurality of electrodes within the SLIM device 104) and a DC potential, thereby performing separation based on mobility and causing ion accumulation. The traveling potential waveform can travel at a predetermined speed, for example, based on the frequency of the voltage signal applied to the electrodes. In some implementations, the traveling potential waveform can have spatial periodicity, and the spatial periodicity can depend on the phase difference between the voltage signals applied to adjacent electrode pairs. In some implementations, the phase difference determines the propagation direction of the potential waveform. In some implementations, the waveform applied to the accumulation / capture / gate electrodes can control the accumulation of ions within the SLIM device 104. The master control circuit can control the frequency and / or phase of the voltage output of the RF / traveling wave / DC control circuits such that the traveling potential waveform has a desired (e.g., predetermined) spatial periodicity and / or speed, and the accumulation waveform / potential sufficiently restricts ion movement and thus accumulates ions.

[0055] In some implementation examples, the controller 108 can be communicatively coupled to the computing device 110. For example, the computing device 110 can provide the operating parameters of the IMS system 100 to the master control circuit via a control signal. In some implementation examples, a user can provide the operating parameters to the computing device 110 (e.g., via a user interface). Based on the operating parameters received via the control signal, the master control circuit can control the operation of the RF / AC / DC control circuit, and the RF / AC / DC control circuit can determine the operation of the connected SLIM device 104. In some implementation examples, the RF / AC / DC control circuit can be physically distributed across the IMS system 100. For example, one or more of the RF / AC / DC control circuits can be disposed within the IMS system 100, and the various RF / AC / DC control circuits can operate based on the power from the power supply 112.

[0056] FIG. 2 is a schematic diagram of a portion of an exemplary SLIM device 104 (e.g., a SLIM device for ion transfer, ion accumulation, ion storage, and / or ion separation) that can be used with the IMS system 100 of FIG. 1. The SLIM device 104 includes a first surface 114a and a second surface 114b. The first and second surfaces 114a, 114b can be arranged (e.g., parallel to each other) so as to define one or more ion channels between the first and second surfaces 114a, 114b. The first surface 114a and the second surface 114b can include electrodes 116, 118a - f, 120a - e, 122a - x (see FIGS. 3 and 4), and these electrodes are arranged as an array of electrodes, for example, on the surface facing the ion channel. The electrodes 116, 118a - 118f, 120a - e, 122a - x on the first surface 114a and the second surface 114b can be electrically connected to the controller 108 and can receive a voltage (or current) signal or waveform from the controller 108. In some implementation examples, on the back surfaces of the first surface 114a and the second surface 114b, a plurality of conductive channels can be included to enable electrical connection between the controller 108 and the electrodes 116, 118a - f, 120a - e, 122a - x on the first surface 114a and the second surface 114b. In some implementation examples, the number of conductive channels can be less than the number of electrodes 116, 118a - f, 120a - e, 122a - x. In other words, a plurality of electrodes 116, 118a - f, 120a - e, 122a - x can be connected to a single electrical channel. As a result, a given voltage (or current) signal can be transmitted to the plurality of electrodes 116, 118a - f, 120a - e, 122a - x simultaneously. Based on the received voltage (or current) signal, the electrodes 116, 118a - f, 120a - e, 122a - x can generate one or more electric potentials (e.g., a superposition of various electric potentials) that can confine, drive, and / or separate ions along a propagation axis (e.g., the z - axis).

[0057] FIG. 3 is a schematic diagram showing a first exemplary arrangement of electrodes 116, 118a - f, 120a - e, 122a - h on the first and second surfaces 114a, 114b of the SLIM device 104. The first and second surfaces 114a, 114b can be substantially mirror images with respect to parallel planes. Thus, the description of the first surface 114a is equally applicable to the second surface 114b. It should be understood that the second surface 114b can also include electrodes having an electrode arrangement similar to that of the first surface 114a.

[0058] The first surface 114a includes a guard electrode 116, a plurality of continuous electrodes 118a - f, and a plurality of segmented electrode arrays 120a - e. Each of the plurality of continuous electrodes 118a - f can receive a voltage (or current) signal or be connected to a ground potential, and can generate a virtual potential that can prevent or suppress ions from approaching the first surface 114a. The plurality of continuous electrodes 118a - f can be rectangular in shape, and the long sides of the rectangle arranged along the ion propagation direction undergo mobility separation along a propagation axis parallel to the z - axis shown in FIG. 3, for example. The plurality of continuous electrodes 118a - f can be separated from each other along a lateral direction that can be orthogonal to the propagation direction, for example, along the y - axis.

[0059] Each of the plurality of segmented electrode arrays 120a - e can be disposed between two consecutive electrodes 118a - f, and includes a plurality of individual electrodes 122a - h, for example 8 electrodes, 16 electrodes, 24 electrodes, etc., arranged along (parallel to) the propagation direction, for example along the z - axis. Each segmented electrode array 120a - e can also include 9 or more or 7 or fewer electrodes, but it should be understood that it should include at least 3 electrodes. For example, as shown in FIG. 4, each of the segmented electrode arrays 120a - e includes 24 electrodes 122a - x. In addition, the individual electrodes 122a - x can be separated into individual groups that receive unique signals from the controller 108, as discussed in more detail below. The plurality of segmented electrode arrays 120a - e can receive a second voltage signal and generate a driving potential that can drive ions along the propagation axis, or a DC voltage signal that can capture ions, as discussed in more detail below. That is, the first and second surfaces 114a, 114b, and their electrode arrangements can be implemented for different purposes, and thus can have different functions based on the voltage settings applied to the continuous electrodes 118a - f, the segmented electrode arrays 120a - e, and the plurality of individual electrodes 122a - h.

[0060] The plurality of continuous electrodes 118a - f and the plurality of segmented electrode arrays 120a - e can be alternately disposed on the first surface 114a between the DC guard electrodes 116. The segmented electrode arrays 120a - e can be traveling - wave (TW) electrodes, and thus each of the individual electrodes 122a - h of each segmented electrode array 120a - e receives a voltage signal that is applied to all of the individual electrodes 122a - h simultaneously, but is phase - shifted between adjacent electrodes 122a - h along the z - axis. However, the same individual electrode of the segmented electrode arrays 120a - e, for example the first individual electrode 122a, receives the same voltage signal without phase - shift.

[0061] The voltage signals applied to the individual electrodes 122a to 122h can be a sine wave form (e.g., an AC voltage waveform), a rectangular waveform, a DC square waveform, a sawtooth waveform, a bias sine waveform, a pulse current waveform, etc., and the amplitude of the signals provided to the individual electrodes 122a to 122h can be determined based on the applied voltage waveform, for example, considering the phase shift described above. For example, A When a single wavelength of the AC voltage waveform extends across eight electrodes (e.g., the individual electrodes 122a to 122h), the amplitude of the voltage signal applied to the individual electrodes 122a to 122h can be determined by selecting a value from the AC waveform regarding the phase shift corresponding to the total number of electrodes associated with a single wavelength (e.g., eight electrodes). For example, the phase shift between adjacent electrodes of the individual electrodes 122a to 122h is 45 degrees (dividing 360 degrees of a single wavelength cycle by 8). This can be realized by electrically connecting the individual electrodes 122a to 122h to different traveling wave control circuits that generate voltage signals with different phases, such as an AC control circuit, a DC (square wave) control circuit, a pulse current control circuit, etc. Alternatively, the controller 108 can also be a single traveling wave control circuit that can generate voltage signals that can be applied to the electrodes 122a to 122h simultaneously. It should be understood that the voltage or current waveform can be in various forms, such as square, triangular, rectangular, sawtooth, etc., and can have periodicity, aperiodicity, etc. For example, the controller 108 can also be a traveling wave control circuit and can include one or more DC (square wave) control circuits that generate DC voltage signals and an AC control circuit that generates sine signals.

[0062] As described above, the controller 108 can include one or more pulse voltage or current control circuits that can generate a pulse voltage (or current) waveform, such as a square wave, triangle wave, rectangular wave, sawtooth wave, etc. The pulse voltage (or current) waveform can have periodicity without polarity reversal. The pulse voltage (or current) control circuit can include a plurality of outputs electrically connected to the individual electrodes 122a - h. In some implementations, the controller 108 can be a pulse voltage (or current) control circuit that can simultaneously apply a plurality of voltage signals (e.g., constituting a pulse waveform) to each of the individual electrodes 122a - h. By superimposing a DC voltage signal and a sine signal, various pulse shapes of the voltage (or current) waveform can be generated. The controller 108 can determine the phase shift between the voltage signals generated by various traveling wave control circuits. The shape / periodicity of the traveling potential waveform can be based on the phase shift between the voltage signals applied to the adjacent electrodes 122a - h. The controller 108 can determine the amplitude of the DC voltage signal generated by the DC control circuit and can determine the amplitude and / or frequency of the AC signal generated by the traveling wave control circuit.

[0063] The frequency of the voltage signal (e.g., AC signal) can determine the speed of the traveling potential waveform. An alternative method of generating an AC signal with a phase shift for the voltage (or current) waveform that generates the traveling potential waveform is to use a polyphase transformer. This method can provide control of the phase relationship between a plurality of voltage output signals based on the connection scheme of the secondary windings of the transformer. In this way, by using one or more input drive voltage signals, a plurality of phase - dependent outputs can be generated by analog circuits only. The main difference between this method and the digital generation method described above is that the phase - dependence can be determined by the physical wiring of the transformer and cannot be changed without physically modifying the wiring. The phase relationship between the digitally generated waveforms can be dynamically varied without hardware changes.

[0064] As time progresses, the potential waveform (e.g., generated by an AC waveform, a sinusoidal voltage waveform, a pulsed voltage [or current] waveform applied to the electrodes) can travel along the propagation direction, e.g., along the z-axis. As a result, it can bring about a change in the amplitude of the voltage applied to the individual electrodes 122a - h. For example, the voltage applied to the first individual electrode 122a during the first time step is applied to the adjacent individual electrode 122b during the next time step. The controller 108 can include one or more traveling wave control circuits that can generate a pulsed voltage / current waveform, an AC waveform, etc. In some implementations, the controller can include one or more RF control circuits that can generate an RF voltage waveform, as will be discussed in more detail below.

[0065] The controller 108 can control the speed of the traveling potential waveform by controlling the frequency and / or phase of the AC / RF / pulsed voltage (or current) waveform applied to the individual electrodes 122a - h. If desired, as the potential waveform travels, the ions introduced into the SLIM device 104 can be pushed along the propagation direction and, optionally, separated along the z-axis based on their mobility. In this regard, the traveling waveform applied by the controller 108 can be used to transfer ions without separating them, or to transfer ions and separate the ions based on their mobility during the transfer.

[0066] As described above, a plurality of continuous electrodes 118a - f can be connected to one or more voltage control circuits, such as the voltage control circuits within the controller 108, and can receive RF signals therefrom. The RF voltage applied to the continuous electrodes 118a - f can have a phase shift with respect to adjacent continuous electrodes 118a - f. That is, adjacent continuous electrodes 118a - f can receive the same RF signal with a 180 - degree phase shift. Accordingly, in the first state, the first, third, and fifth electrodes 118a, 118c, 118e can have a positive polarity (shown as RF+), and the second, fourth, and sixth continuous electrodes 118b, 118d, 118f can have a negative polarity (shown as RF - ). As time and the signal progress, the polarity of each of the continuous electrodes 118a - f switches. The above functions hold ions between the first and second surfaces 114a, 114b and prevent the ions from contacting the first and second surfaces 114a, 114b.

[0067] As described above, the SLIM device 104 can have nine or more or seven or fewer individual electrodes 122a - h for each of the segmented electrode arrays 120a - e, and can include six or more or four or fewer segmented electrode arrays 120a - e and six continuous electrodes 118a - f depending on the desired function of the SLIM device 104. For example, FIG. 4 is a schematic diagram showing a second and third exemplary arrangement of the electrodes 116, 118a - f, 120a - e, 122a - x on the first and second surfaces 114a, 114b of the SLIM device 104. More specifically, the arrangement of the electrodes 116, 118a - f, 120a - e, 122a - x shown in FIG. 4 is substantially the same as the arrangement shown in FIG. 3, but each of the segmented electrode arrays 120a - e has 24 individual electrodes 122a - x, the six continuous electrodes 118a - f are divided into three groups, and the guard electrodes 116 are divided into three groups.

[0068] In this configuration, the eight individual electrodes 122a - h of the first set can be used for the first function, for example, to transmit ions regardless of whether ions are separated or not. The eight individual electrodes 122i - p of the second set can be used for the second function, for example, to capture and accumulate ions. The eight individual electrodes 122q - x of the third set can be used for the third function, for example, to transmit ions while separating ions. For example, the controller 108 can provide a first waveform to the eight individual electrodes 122a - h of the first set, a second waveform to the eight individual electrodes 122i - p of the second set, and a third waveform to the eight individual electrodes 122q - x of the third set. Additionally, depending on the desired function, each of the individual electrodes 122a - x can be individually controlled by the controller 108 to provide a waveform or voltage (e.g., a DC voltage value), or can be switched between different waveforms or voltages. Accordingly, if necessary, the individual electrodes 122a - x can be divided into groups according to design considerations.

[0069] FIG. 5 is a block diagram showing an exemplary region of the SLIM device 104 of FIG. 2. As shown in FIG. 5, the individual electrodes 122a - x can be grouped into different regions based on their desired functions. For example, the SLIM device 104 includes a transmission region 124, It can include an accumulation region 126 and a separation region 128. A traveling wave for transmitting ions to the accumulation region 126 can be applied to the transmission region 124. The accumulation region 126 can capture and accumulate ions, for example, by implementing one or more switching / gate electrodes. The separation region 128 can separate and transmit the ions released from the accumulation region 126. The electrode arrangement shown in FIG. 3 can be implemented in any of the transmission region, the accumulation region, and the separation region 124, 126, 128, and the voltage applied to each electrode determines the function. For example, the first set of eight individual electrodes 122a - h in FIG. 4 can be implemented as the transmission region 124, the second set of eight individual electrodes 122i - p in FIG. 4 can be implemented as the accumulation region 126, and the third set of eight individual electrodes 122q - x in FIG. 4 can be implemented as the separation region 128.

[0070] In addition, as shown in FIGS. 4 and 5, the accumulation region 126 can be provided with a separate set of continuous electrodes 118a - f and a separate set of guard electrodes 116, these electrodes can be individually controlled, and different voltages can be applied to the electrodes by the controller 108. This configuration enables different RF and DC voltages to be applied to the accumulation region 126. For example, the amplitude of the RF voltage applied to the continuous electrodes 118a - f in the accumulation region 126 can be reduced to avoid ion excitation, and the RF voltage applied to the continuous electrodes 118a - f in the accumulation region 126 and the DC guard voltage applied to the guard electrodes 116 in the accumulation region 126 can be adjusted to match the voltage applied to the second set of individual electrodes 122i - p in the accumulation region 126.

[0071] FIG. 6 is a schematic block diagram showing an example set of waveforms applied to regions 124, 126, 128 of the SLIM device 104, and exemplary ion movement through regions 124, 126, 128. A first traveling wave 130 is applied to the transfer region 124 to transfer ions 132a - c to the accumulation region 126 along a propagation axis, e.g., the z - axis. The first traveling wave 130 can be generated by the controller 108 and can be customized to transfer the ions 132a - c whether or not the ions 132a - c are separated based on mobility. The transfer region 124 can include a plurality of individual electrodes 122a - x of each of the segmented electrode arrays 120a - e. For example, the first through eighth individual electrodes 122a - h for all of the segmented electrode arrays 120a - e can receive the first traveling wave 130 and transfer the ions 132a - c to the accumulation region 126. Since the first traveling wave 130 extends into the accumulation region 126, the accumulation region 126 can partially overlap the transfer region 124.

[0072] Accumulation region 126 can have two different states / operating modes, for example, a capture state and a release state, that is, it can operate over different periods. When in the capture state / operating mode, the first traveling wave 130 can extend into the accumulation region 126, and the signal applied to a single gate electrode 131, for example, the first individual electrode 122a (for example, the 17th individual electrode 122q in FIG. 4) of each segmented electrode array 120a - e in the separation region 128, or the eighth individual electrode 122h (for example, the 16th individual electrode 122p in FIG. 4) of each segmented electrode array 120a - e in the accumulation region 126, can be switched from the first traveling wave 130 to a signal configured to capture the ions 132a - c or prevent the continuous propagation of the ions 132a - c. More specifically, the gate electrode receives a high DC potential voltage signal 134 from the controller 108, which has a potential higher than the voltage bias of the first traveling wave 130. The voltage bias of the first traveling wave 130 is generally a fixed DC voltage applied to the first traveling wave 130 to shift the waveform. Thus, the first traveling wave 130 continuously transmits the ions 132a - c provided to the SLIM device 104, for example, along the propagation axis from the ionization source 102 until the ions 132a - c reach the gate electrode 131. When they reach the gate electrode 131, the ions 132a - c are stopped, for example, repelled by the high DC potential voltage signal 134. Nevertheless, the continuously circulating first traveling wave 130 prevents the ions 132a - c from propagating in the opposite direction, for example, the negative z - axis direction, and instead captures the ions 132a - c from the high DC potential voltage signal 134 by continuously pushing the ions 132a - c in the propagation direction, for example, the positive z - axis direction, thereby enabling the ions 132a - c to accumulate within the accumulation region 126. As a result, the ions 132a - c are essentially packetized and can thus be separated in a batch within the separation region 128.

[0073] Accordingly, during operation, when in the capture state / operation mode, ions 132a - c can be continuously sent to the SLIM device 104 until a sufficient number of ions are accumulated. Whether a sufficient number of ions have been accumulated can be determined by whether the space charge limit has been reached. More specifically, the space charge effect limits the maximum number of charges that can be accommodated in a given length until the ions are emitted. Generally, the space charge limit is about one million charges per millimeter of path length within the SLIM device 104. Accordingly, electrode segments, illustrated and described in connection with FIG. 3, which include a single traveling wave segment, e.g., six RF electrodes 118a - f, and five segmented electrode arrays 120a - e having eight individual electrodes 122a - h, are used to accumulate ions. The segment is, for example, 9 millimeters in length, and at that time the space charge limit (e.g., the storage capacity) is about nine million charges. That is, up to the space charge limit, nine million charges can be accumulated, and when the space charge limit is exceeded, ions may be lost from the trap. Note that the space charge limit is based on the total charge value of all the accumulated ions, not the number of ions. For example, some ions may have a larger charge value, e.g., +40 or +50, and in such a situation, fewer ions should be accumulated than when ions having a charge of +10 are accumulated. Further, although a single traveling wave segment having six RF electrodes 118a - 118f and five segmented electrode arrays 120a - e was assumed above, if additional capacity is required, e.g., to increase the sensitivity of the analysis, additional rows can be added to increase the storage capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode can also be added to the electrode configuration shown in FIGS. 3 and 4, thereby providing additional space for ion accumulation.

[0074] The gate electrode 131 can be a switchable electrode and thus can operate in a capture state for a first period until a sufficient number of ions are accumulated, and then the signal applied to the gate electrode 131 can be switched to a release state, and the gate electrode 131 can operate in the release state for a second period. For example, the signal can be switched from the high DC potential voltage signal 134 to the second traveling wave 136, and thus the accumulated ions 132a - c are released into the separation region 128 in synchronization with the second traveling wave 136 applied to the separation region 128. The second traveling wave 136 can be generated by the controller 108, applied to the electrodes of the separation region 128, separate the ions 132a - c along the z - axis based on their mobility, and push the ions 132a - c in the propagation direction, e.g., along the z - axis, towards the mass spectrometer 106 for analysis. The separation region 128 can include a plurality of individual electrodes 122a - x of each of the segmented electrode arrays 120a - e. For example, the 17th to 24th individual electrodes 122q - x (see FIG. 4) for all of the segmented electrode arrays 120a - e can receive the second traveling wave 136. The transfer region 124 can also function as a separation region, and thus the first traveling wave 130 is the same as the second traveling wave 136, and it should be noted that this can assist in synchronizing the first and second traveling waves 130, 136 when switching between the capture state / operation mode and the release state / operation mode.

[0075] FIG. 7A is a schematic block diagram showing an exemplary second set of waveforms applied to regions 124, 126, 128 of the SLIM device 104, including the first release state waveforms (release states 1A and 1B), and exemplary ion motion through regions 124, 126, 128. FIG. 7B is a schematic block diagram showing an exemplary second set of waveforms as shown in FIG. 7A having a second release state waveform.

[0076] As described above, a first traveling wave 130 is applied to the transmission region 124 to transmit ions 132a-c along the propagation axis, for example, the z-axis, to the accumulation region 126. The first traveling wave 130 can be generated by the controller 108 and can be customized to transmit the ions 132a-c regardless of whether the ions 132a-c are separated based on mobility. The transmission region 124 can include a plurality of individual electrodes 122a-x of each of the segmented electrode arrays 120a-e. For example, the first to eighth individual electrodes 122a-h for all of the segmented electrode arrays 120a-e can receive the first traveling wave 130 and transmit the ions 132a-c to the accumulation region 126. Since the first traveling wave 130 extends into the accumulation region 126, the accumulation region 126 can partially overlap the transmission region.

[0077] The accumulation region 126 can have two different states / operation modes, for example, a capture state / operation mode and a release state / operation mode, that is, it can operate over different periods. When in the capture state / operation mode, the first traveling wave 130 can extend into the accumulation region 126, and the signal applied to the plurality of gates / capture electrodes can be switched from the first traveling wave 130 to a signal configured to capture the ions 132a-c or prevent the ions 132a-c from continuing to propagate. For example, two electrodes can be implemented as gates / capture electrodes, for example, the first and second individual electrodes 122a, 122b (for example, the ninth and tenth individual electrodes 122i, 122j in FIG. 4) of each of the segmented electrode arrays 120a-e (see FIG. 3) within the accumulation region 126, or the seventh and eighth individual electrodes 122g, 122h (for example, the fifteenth and sixteenth individual electrodes 122o, 122p in FIG. 4) of each of the segmented electrode arrays 120a-e (see FIG. 3) within the accumulation region 126, or the entire array of the individual electrodes 122a-h of each of the segmented electrode arrays 120a-e (see FIG. 3) within the accumulation region 126 (for example, the ninth to sixteenth individual electrodes 122i-p in FIG. 4) can be implemented as gates / capture electrodes.

[0078] More specifically, the gate / capture electrodes (e.g., the seventh and eighth electrodes 122g, 122h) receive a low DC potential voltage signal 140 from the controller 108 over a first period, thereby creating a potential well (e.g., a DC potential well) that is lower in potential than the voltage biases of the first traveling wave 130 and the second traveling wave 142 in the separation region 128. Thus, the first traveling wave 130 continuously transmits the ions 132a-c provided from the ionization source 102 to the SLIM device 104 along the propagation axis until the ions 132a-c reach the gate / capture electrodes 122g, 122h. At the gate / capture electrodes 122g, 122h, the ions 132a-c are captured because they cannot overcome the potential of the second traveling wave 142 in the separation region 128. Similarly, the continuously circulating first traveling wave 130 prevents the ions 132a-c from propagating in the opposite direction, e.g., the negative z-axis direction, and captures the ions 132a-c in the low potential well 140, thereby accumulating the ions 132a-c in the accumulation region 126, e.g., in the low potential well 140. Thereby, the ions 132a-c are essentially packetized and can thus be separated in a batch within the separation region 128.

[0079] Accordingly, during operation, when in the capture state / operation mode, the ions 132a-c can be continuously sent out to the SLIM device 104 until a sufficient number of ions are accumulated in the low potential well 140 and the accumulation region 126. As discussed above, whether a sufficient number of ions have accumulated can be determined by whether the space charge limit has been reached. However, since the storage region 126, such as the low potential well 140, extends across a plurality of electrodes, it is possible to create a low potential well using three or more electrodes and accumulate a larger number of ion charges, thus controlling the capacity of the trap. Further, if additional capacity is required, for example, to increase the sensitivity of the analysis, additional rows can be added to increase the storage capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode can also be added to the electrode configurations shown in FIGS. 3 and 4, thereby providing additional space for ion storage.

[0080] The gate / capture electrodes 122g, 122h can be made switchable electrodes, and thus after a sufficient number of ions have been accumulated, the signal applied to the gate / capture electrodes 122g, 122h can be switched to the release state. For example, as shown by the release state 1A in FIG. 7A, the signal applied to the gate / capture electrodes 122g, 122h is switched from the low DC potential voltage signal 140 to a sloped DC potential voltage signal 144 (e.g., a DC potential gradient) that progresses across the gate / capture electrodes 122g, 122h while decreasing in potential, so as to push the accumulated / captured ions 132a - c towards the separation region 128, thereby releasing the accumulated ions 132a - c into the separation region 128. The second traveling wave 142 can be generated by the controller 108, is applied to the separation region 128, and is configured to transmit the ions 132a - c from the accumulation region 126 to the separation region 128 for propagation and separation in association or synchronization with the sloped DC potential voltage signal 144. The second traveling wave 142 separates the ions 132a - c along the z - axis based on their mobility and pushes the ions 132a - c in the propagation direction, e.g., along the z - axis, towards the mass spectrometer 106 for analysis. The separation region 128 can include a plurality of individual electrodes 122a - x among each of the segmented electrode arrays 120a - e. For example, the 17th to 24th individual electrodes 122q - x for all of the segmented electrode arrays 120a - e (see FIG. 4) can receive the second traveling wave 142. It should be noted that the transfer region 124 can also function as a separation region, and thus the first traveling wave 130 is the same as the second traveling wave 136.

[0081] Alternatively, as shown by the release state 1B in FIG. 7A, the second traveling wave 142 can be shifted from the first traveling wave 130. For example, a lower voltage bias than that applied to the first traveling wave 130 can be applied to the second traveling wave 142. In this configuration, the DC potential voltage signal 140 can be configured to descend and transition from the voltage bias of the first traveling wave 130 to the voltage bias of the second traveling wave 142, and push the ions 132a - 132c from the accumulation region 126 to the separation region 128 for propagation and separation.

[0082] Instead of implementing the ramp DC potential voltage signal 144 during the release state / mode, the controller 108 can provide a third traveling wave 146 to the gate / capture electrodes 122g, 122h when in the release state / mode, as shown in FIG. 7B showing the second release state waveform. That is, the signal provided to the gate / capture electrodes 122g, 122h can be switched from the low DC potential voltage signal 140 to the third traveling wave 146, and the third traveling wave 146 is associated or synchronized with the first traveling wave 130 and / or the second traveling wave 142, and when the second traveling wave 142 is applied, the accumulated / captured ions 132a-c can be pushed towards the separation region 128 and configured to enter the separation region 128. As discussed above, the second traveling wave 142 can be generated by the controller 108 and configured to transfer the ions 132a-c from the accumulation region 126 to the separation region 128 for propagation and separation in association or synchronization with the third traveling wave 146.

[0083] In addition, as described in connection with FIG. 4, a separate set of continuous electrodes 118a-f and a separate set of guard electrodes 116 can be provided in the accumulation region 126, these electrodes can be individually controlled, and different voltages can be applied to these electrodes by the controller 108. With this configuration, different RF and DC voltages are applied to the accumulation region 126 This becomes possible. For example, when the accumulation region 126 is in the capture state and thus receives the low DC potential voltage signal 140, the amplitude of the RF voltage applied to the continuous electrodes 118a - f in the accumulation region 126 can be reduced to avoid ion excitation, and the DC guard voltage applied to the guard electrode 116 in the accumulation region 126 can be reduced and maintained at a level that ensures that ions do not escape from these sides while matching the voltage applied to the individual electrodes 122i - p in the accumulation region 126. In addition, when the accumulation region 126 is switched to the release state, the RF voltage applied to the continuous electrodes 118a - f and the DC guard voltage applied to the guard electrode 116 can be adjusted, which involves a change in the voltage signal applied to the individual electrodes 122i - p. For example, if the voltage signal applied to the individual electrodes 122i - p during the release state is increased, the DC guard voltage applied to the guard electrode 116 can be increased to ensure that ions do not escape from the side of the SLIM device 104.

[0084] FIG. 8 is a schematic block diagram showing a third set of exemplary waveforms applied to the exemplary regions 124, 126, 128 of the SLIM device 104, and exemplary ion movement through the regions 124, 126, 128. In particular, FIG. 8 demonstrates an implementation example in which opposing traveling waves are used to capture and accumulate ions. As described above, a first traveling wave 130 is applied to the transfer region 124 to transfer ions 132a - c along the propagation axis, e.g., the z - axis, to the accumulation region 126. The first traveling wave 130 can be generated by the controller 108 and can be customized to transfer the ions 132a - c regardless of whether the ions 132a - c are separated based on mobility. The transfer region 124 can include a plurality of individual electrodes 122a - x of each of the segmented electrode arrays 120a - e. For example, the first through eighth individual electrodes 122a - h for all of the segmented electrode arrays 120a - e can receive the first traveling wave 130 and transfer the ions 132a - c to the accumulation region 126.

[0085] Similarly, a second traveling wave 142 can be applied to the separation region 128, and the second traveling wave 142 can be generated by the controller 108. The separation region 128 can include a plurality of individual electrodes 122a - x of each segmented electrode array 120a - e. For example, the 17th to 24th individual electrodes 122q - x for all the segmented electrode arrays 120a - e (see FIG. 4) can receive the second traveling wave 142. Thus, the second traveling wave 142 can start when the first traveling wave 130 ends. In this regard, the second traveling wave 142 can have the same waveform as the first traveling wave 130, and thus these waveforms essentially form a single continuous wave.

[0086] However, the SLIM device 104 can have two different states / operation modes, for example, a capture state / operation mode and a release state / operation mode, that is, it operates over different periods. When in the capture state / operation mode, the controller 108 can apply a third traveling wave 148 that travels towards the first traveling wave 130, for example, along the negative direction of the z - axis, in a direction opposite to that of the first traveling wave 130, to the separation region, for example, the 17th to 24th individual electrodes 122q - x, over a certain period. Accordingly, the first traveling wave 130 and the third traveling wave 148 can be opposite waves that intersect in the accumulation region 126. In addition, the third traveling wave 148 can have the same frequency and magnitude as the first traveling wave 130 but propagates in the opposite direction. In this configuration, the individual electrodes 122q - x of the separation region can be made switchable, and thus the controller 108 applies the third traveling wave 148 to the individual electrodes 122q - x during the capture state / operation mode and the second traveling wave 142 during the release state / operation mode.

[0087] Thus, when the SLIM device 104 operates in the capture state / operation mode, the first traveling wave 130 causes the ions 132a - c to accumulate in the accumulation region 126, for example, the 8th electrode 122h and Until reaching a point between the 9th electrode 122i, ions 132a - c provided to the SLIM device 104 are continuously transmitted along the propagation axis from, for example, the ionization source 102. When reaching the accumulation region 126, ions 132a - c are stopped by the opposing first and third traveling waves 130, 148. That is, the first traveling wave 130 pushes ions 132a - c along the positive direction of the z - axis, and the second traveling wave 142 pushes ions 132a - c in the opposite direction, which is the negative direction of the z - axis. Thus, the continuously circulating third traveling wave 148 prevents ions 132a - c from further propagating across the SLIM device 104 along the z - axis, and the continuously circulating first traveling wave 130 transmits ions 132a - c to the accumulation region 126 and then prevents ions 132a - c from propagating along the z - axis in the opposite direction, for example, in the negative direction. The opposing first and third traveling waves 130, 148 prevent ions 132a - c located within the accumulation region 126 from traveling a large distance along the z - axis, thus capturing ions 132a - c and enabling ions 132a - c to accumulate within the accumulation region 126. Thereby, ions 132a - c are essentially packetized and can thus be separated in a batch within the separation region 128.

[0088] Accordingly, during operation, when in the capture state / operation mode, ions 132a - c can be continuously sent into the SLIM device 104 until a sufficient number of ions are accumulated within the accumulation region 126. As discussed above, whether a sufficient number of ions have accumulated can be determined by whether the space - charge limit has been reached. Further, when additional capacity is required, for example, to increase the sensitivity of the analysis, additional rows can be added to increase the accumulation capacity per unit length. For example, a sixth segmented electrode array and an eighth continuous RF electrode can also be added to the electrode configurations shown in FIGS. 3 and 4, thereby providing additional space for ion accumulation.

[0089] As described above, the electrodes 122q - x in the separation region can be switchable electrodes, and thus after a sufficient number of ions have been accumulated, the signal applied to the electrodes 122q - x can be switched to the release state. For example, this signal can be switched from the third traveling wave 148 to the second traveling wave 142 and synchronized with the first traveling wave 130 applied to the transfer region, thereby releasing the accumulated ions 132a - c into the separation region 128. The second traveling wave 136 can be generated by the controller 108, applied to the separation region 128, separate the ions 132a - c along the z - axis based on their mobility, and push the ions 132a - c towards the mass spectrometer 106 along the propagation direction, for example, the z - axis for detection. The transfer region 124 can also function as a separation region, and thus the first traveling wave 130 is the same as the second traveling wave 136, and it should be noted that this can assist in synchronizing the first and second traveling waves 130, 136 when switching between the capture state / operation mode and the release state / operation mode.

[0090] FIG. 9 is a block diagram showing an exemplary arrangement of the transfer region, accumulation region, and separation regions 124, 126, 128 within the IMS system 100 of the present disclosure for accumulating and separating ions. As shown in FIG. 9, the IMS system 100 can include multiple transfer regions 124, accumulation regions 126, and separation regions 128 in order to further increase the resolution. It should be noted that alternative arrangements and configurations are also contemplated by the present disclosure. In this regard, it should be noted that the different regions 124, 126, 128 do not need to be arranged linearly. Instead, for example, the transfer region 124 can be arranged orthogonally to the accumulation region or separation region 126, 128. Additionally, a gate can be implemented by the present disclosure to control the flow of ions, for example, from the transfer region 124 to the accumulation region 126 or from the separation region 128 to a second accumulation region 126.

[0091] FIG. 10 is a schematic diagram of an exemplary accumulation region 150 of the present disclosure that can be implemented as the accumulation region 126 illustrated and described, for example, in relation to FIGS. 5 - 9. That is, as described above It should be understood that the description of the storage region 126 and its functions, including the imprint waveform, capture state, and release state, is equally applicable to the storage region 150 shown in FIG. 10.

[0092] The storage region 150 includes an inlet section 152, an inlet transition section 154, an ion storage section 156, an outlet transition section 158, and an outlet section 160. As will be discussed in more detail below, each of sections 150-160 generally includes a plurality of rows of continuous electrodes 162 and a plurality of segmented electrode arrays 164, and the number of these electrodes can vary between sections 150-160. In this regard, as shown in FIG. 10, some of the rows of continuous electrodes 162 and segmented electrode arrays 164 can extend through two or more of sections 150-160, and some can extend through all of sections 150-160 of the storage region 150. The continuous electrodes 162 can be made substantially similar to the continuous electrodes 118a-f illustrated and described in connection with FIGS. 3 and 4, and the segmented electrode arrays 164 can be made substantially similar to the plurality of segmented electrode arrays 120a-e illustrated and described in connection with FIGS. 3 and 4. Similar to the segmented electrode arrays 120a-e, the segmented electrode arrays 164 can include a plurality of individual electrodes 122a-h. For simplicity of illustration, it should also be noted that in FIG. 10, not all of the continuous electrodes 162, segmented electrode arrays 164, and individual electrodes 122a-h are indicated by reference numerals; instead, a suitable representative number of elements are indicated by reference numerals.

[0093] The inlet section 152 and the outlet section 160 can each include, for example, six rows of continuous electrodes 118a - f and five segmented electrode arrays 164. However, it should be understood that more or fewer rows and segmented electrode arrays can also be included. The inlet section 152 can be configured to receive ions from another section of the SLIM device 104, and the outlet section 160 can be configured to provide ions to another section of the SLIM device 104. For example, the inlet and outlet sections 152, 160 can be positioned adjacent to the transfer region 124, the separation region 128, different accumulation regions 126, 150, or any other region of the SLIM device 104 to receive ions from or provide ions to that region. Accordingly, the voltage signals, such as traveling wave voltage signals, applied to the individual electrodes 122a - h of the segmented electrode array 164 of the inlet section 152 and the outlet section 160 can be coordinated with the voltage signals applied to the adjacent sections of the SLIM device 104 to fully integrate and match these signals. The present disclosure also contemplates at least one embodiment where, additionally and / or alternatively, the inlet section 152 can be implemented as an outlet, and additionally and / or alternatively, the outlet section 160 can be implemented as an inlet. For example, the ion accumulation section 156 can be implemented not only for accumulating ions but also as a switching region for selectively guiding ions to the inlet section 152 (used as an outlet) or the outlet section 160.

[0094] The entrance transition section 154 extends from the entrance section 152 to the ion accumulation section 156 and widens in width as it progresses from the entrance section 152 to the ion accumulation section 156 along the z-axis. Accordingly, the width of the entrance transition section 154 along the y-axis is greater at the position adjacent to the ion accumulation section 156 than at the position adjacent to the entrance section 152. In addition, the number of rows of the continuous electrodes 162 and the segmented electrode arrays 164 gradually increases as the width of the entrance transition section 154 widens. Conversely, the exit transition section 158 tapers and reduces in width as it progresses from the ion accumulation section 156 to the exit section 160 along the z-axis. Accordingly, the width of the exit transition section 158 along the y-axis is greater at the position adjacent to the ion accumulation section 156 than at the position adjacent to the exit section 160. In addition, the number of rows of the continuous electrodes 162 and the segmented electrode arrays 164 gradually decreases as the width of the exit transition section 158 reduces.

[0095] The accumulation region 150 is designed such that the ion accumulation section 156 is wider than the entrance section 152, the exit section 160, and / or other portions of the path through the SLIM device 104, for example, along the y-axis orthogonal to the ion propagation axis (z-axis in FIG. 10). The accumulation region 150 is also designed such that the entrance transition section 154 and the exit transition section 158 provide a gradual transition between the entrance and exit sections 152, 160 and the accumulation section 156. Accordingly, the accumulation section 156 includes more rows of electrodes, such as rows of the continuous electrodes 162 and the segmented electrode arrays 164, than other portions of the path through the SLIM device 104. For example, as shown in FIG. 10, the accumulation section 156 can include 16 rows of the continuous electrodes 162 and 15 segmented electrode arrays 164, and the entrance section 152 and the exit section 160 designed to be associated with other portions of the path through the SLIM device 104 include 6 rows of the continuous electrodes 162 and 5 segmented electrode arrays 164.

[0096] In addition, as described in connection with FIG. 5, the segmented electrode array 164 of the accumulation section 156 can be divided into a plurality of groups or segments. For example, each segmented electrode array 164 of the accumulation section 156 can include three groups or segments (e.g., 24 electrodes) of eight individual electrodes 122a-h. The number of segmented electrode array groups and / or the number of individual electrodes 122a-h per segmented electrode array group can be increased or decreased according to the implementation example and experimental requirements. In addition, the individual electrodes 122a-h of the segmented electrode array 164 of the accumulation section 156 can receive traveling wave signals independently of the transition sections 154, 158, the inlet section 152, and the outlet section 160, thereby making it possible to switch the traveling wave direction, and thus the ion traveling direction through the accumulation section 156, as needed. It should also be understood that the accumulation region 150 can operate in the same manner as that illustrated and described in connection with FIGS. 6-8.

[0097] Furthermore, each segmented electrode array 164 of the accumulation section 156 can have one or more gate electrodes 166, such as the eighth electrode 122h of the third segmented electrode array group, and a signal can be applied to one or more gate electrodes 166 to capture ions 132a-c or prevent the ions 132a-c from continuously propagating through the accumulation region 150. More specifically, the gate electrode 166 can receive a high DC voltage signal from the controller 108 and generate a high DC electric field (V / m) to capture ions within the accumulation section 156 when ions are provided to the accumulation section 156 by the inlet section 152, the inlet transition section 154, and the individual electrodes 122a-h preceding the gate electrode 166. The accumulated ions are also held laterally, e.g., in the y-axis direction, by the DC guard electrode 168, and the DC guard electrode 168 is located on the sides of the sections 152-160 of the accumulation region 150 and functions according to the guard electrode 116 illustrated and described in connection with FIGS. 3 and 4. By expanding the width of the accumulation section 156, more ions can be held before encountering space charge problems compared to a narrower accumulation section, such as the inlet section 152 or an accumulation section 156 of the same width as the remainder of the path through the SLIM device 104.

[0098] After a desired number of ions have been accumulated within the accumulation section 156, the high DC voltage signal can be removed, and a traveling wave signal can be applied that cooperates with the traveling wave signal applied to the other individual electrodes 122a-h within the accumulation section 156 and the traveling wave signal applied to the outlet transition section 158. After the high DC voltage signal is removed and the traveling wave signal is applied, the ions are biased into the outlet transition section 158.

[0099] As described above, the exit transition section 158 tapers from the ion accumulation section 156 to the exit section 160. For example, the exit transition section 158 shown in FIG. 10 narrows from 31 rows to 11 rows. This tapering allows ions to be transmitted from the accumulation section 156 to the exit section 160 while generally avoiding the ions reaching the space charge limit and being emitted by the space charge effect. In this regard, faster ions, such as ions with a larger ion mobility, exit the accumulation section 156 more rapidly than slower ions, so the ions are separated as they cross the exit transition section 158. Accordingly, a larger area is required near the gate electrode 166 to accommodate the cumulative charge of the released ions that are not yet separated at the start of the exit transition section 158 and to prevent the ions from reaching the space charge limit. However, as the ions are separated, the cumulative charge of the released ions at a given position along the length of the exit transition section 158 is reduced, and thus it becomes possible to gradually reduce the width of the exit transition section 158 to match the width of the exit section 160. In addition, the ions are held within the exit transition section 158 by the DC guard electrode 168 and are prevented from exiting laterally, e.g., along the y-axis. It should be understood that the length of the exit transition section 158 and the slope of its taper can be adjusted according to the number of charges accumulated within the ion accumulation section 156. For example, the exit transition section 158 shown in FIG. 10 has a length of 16 individual electrodes 122a - h, e.g., two groups of 8 individual electrodes 122a - h, but if it is determined that this is sufficient, it can also be provided as 8 individual electrodes 122a - h. The exit section 160 receives ions from the exit transition section 158 and transmits the ions to another section of the SLIM device 104.

[0100] FIG. 11 is a schematic diagram of an exemplary accumulation region 150 of FIG. 10, with a lateral inlet section 170 connected to the accumulation region 150. Specifically, in some aspects of the present disclosure, the ion accumulation section 156 can have openings on one or both lateral sides thereof, and the lateral inlet section 170 is positioned adjacent to the opening. The lateral inlet section 170 can be substantially similar to the inlet section 152, and can include a plurality of columns of continuous electrodes 162 including a plurality of individual electrodes 122a - h and a plurality of segmented electrode arrays 164 (oriented vertically along the y-axis rather than horizontally along the z-axis as in the inlet section 152). The lateral inlet section 170 is configured to directly transfer ions into the ion accumulation section 156.

[0101] The ion accumulation section 156 can be utilized to accumulate ions and can function in accordance with the above description provided in connection with FIG. 10. In particular, the gate electrodes 166a, 166b can receive a high DC voltage signal from the controller 108 and can generate a high DC electric field (V / m) to capture ions within the accumulation section 156 when ions are provided to the accumulation section 156 by the lateral inlet section 170. In this regard, the ion accumulation section 156 can include two sets of gate electrodes 166a, 166b on both sides of the ion accumulation section 156, and can provide a confinement region between the two sets of gate electrodes 166a, 166b.

[0102] After the desired number of ions have been accumulated within the accumulation section 156, the ions can be transferred to the exit section 160 or the entrance section 152, and the entrance section 152 can also function as an exit section as long as appropriate traveling waves are applied to the entrance section 152 and the entrance transition section 154. In particular, when ions are sent to the exit section 160, the high DC voltage signal is removed from the right gate electrode 166b, and a traveling wave signal traveling in the positive direction along the z-axis is applied to the individual electrodes 122a - h within the accumulation section 156 to push the ions into the exit transition section 158 and then into the exit section 160. In the exit section 160, the ions can be provided to another path section of the SLIM device 104. As an alternative, when ions are sent to the entrance section 152, the high DC voltage signal is removed from the left gate electrode 166a, and a traveling wave signal traveling in the negative direction along the z-axis is applied to the individual electrodes 122a - h within the accumulation section 156, the entrance transition section 154 (which functions in the same manner as the exit transition section 158), and the entrance section 152 (which functions in the same manner as the exit section 160) to push the ions into the entrance transition section 154 and then into the entrance section 152. In the entrance section 152, the ions can be provided to another path section of the SLIM device 104. Accordingly, the ion accumulation section 156 is independently controllable and can be utilized to direct ions in different directions. Thus, the accumulation region 150 can be utilized not only for accumulating ions but also as a direction switch. It should also be understood that the accumulation region 150 can be utilized as a direction switch that does not initially accumulate ions.

[0103] In addition, the transition sections 154, 158 can be configured and sized substantially the same, for example, they can have the same length and / or slope, or can have different configurations and / or shapes as shown in FIG. 11. It should be understood that, for example, the design of the transition sections 154, 158 can be adjusted specifically based on the desired implementation example, and then the path section of the SLIM device 104 can be arranged.

[0104] Other embodiments are within the scope and spirit of the disclosed subject matter. One or more examples of these embodiments are shown in the accompanying drawings. The systems, devices, and methods specifically described herein and illustrated in the accompanying drawings are exemplary embodiments that do not limit, and it will be understood by those skilled in the art that the scope of the present disclosure is defined only by the claims. The configurations illustrated or described in connection with one exemplary embodiment can also be combined with the configurations of other embodiments. Such modifications and variations are intended to be included within the scope of the present disclosure. Further, in the present disclosure, components with the same name in the embodiments generally have similar configurations, and thus each configuration of each component with such a name is also within the scope even in a specific embodiment where it is not necessarily fully detailed.

[0105] The subject matter described in this specification can be implemented in a digital electronic circuit, or in computer software, firmware, hardware, or combinations thereof, that include the structural means disclosed in this specification and its structural equivalents. The subject matter described in this specification can be implemented as one or more computer program products, such as one or more computer programs tangibly embodied in an information carrier (e.g., a machine-readable storage device), or in a propagated signal for execution by, or to control the operation of, a data processing apparatus (e.g., a programmable processor, a computer, or multiple computers). A computer program (also known as a program, software, software application, or code) can be written in any form of programming language, including a compiled or interpreted language, and can be introduced in any form, including as a stand-alone program or module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file. A program can be stored as part of a file that holds other programs or data, in a single file dedicated to the program, or in multiple related files (e.g., files that store one or more modules, subprograms, or portions of code). A computer program can be introduced to be executed on one computer or multiple computers at one location, or can be distributed across multiple locations and interconnected by a communication network.

[0106] The processes and logical flows described herein that include the method steps of the subject matter described herein can be executed by one or more programmable processors executing one or more computer programs to perform the functions of the subject matter described herein by operating on input data to generate output. The processes and logical flows can also be executed by special purpose logic circuitry, such as an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the apparatus of the subject matter described herein can be implemented as such special purpose logic circuitry.

[0107] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor can receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer can also include one or more mass storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, or can be operatively coupled to receive data from, or transfer data to, such storage devices, or both. Information carriers suitable for embodying computer program instructions and data include, by way of example, non-volatile memory, such as semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices); magnetic disks (e.g., internal hard disks or removable disks); magneto-optical disks; and optical disks (e.g., CD and DVD disks) in any form. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0108] To provide interaction with a user, the subject matter described herein can be implemented on a computer having a display device, such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user, as well as a keyboard and a pointing device (e.g., a mouse or trackball) by which the user can provide input to the computer. Other types of devices can be used to provide interaction with the user as well. For example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback), and input from the user can be received in any form including acoustic, vocal, or tactile input.

[0109] The techniques described herein can be implemented using one or more modules. As used herein, the term "module" refers to computing software, firmware, hardware, and / or various combinations thereof. However, at a minimum, a module should not be construed as software implemented on or recorded on a non-transitory processor-readable recordable storage medium that is not hardware or firmware (i.e., a module is not software per se). In fact, a "module" should always be construed to include at least some physical non-transitory hardware, such as part of a processor or computer. Two different modules can share the same physical hardware (e.g., two different modules can use the same processor and network interface). The modules described herein can be integrated, combined, separated, and / or replicated to accommodate various applications. Also, the functions described herein performed by a particular module can be performed instead of or in addition to the functions performed by a particular module It can also be executed in one or more other modules and / or by one or more other devices. Further, the module can be implemented across multiple devices and / or other components that are local or remote to each other. Additionally, the module can be moved from one device and added to another device and / or included in both devices.

[0110] The subject matter described in this specification can be implemented in a computing system that includes back-end components (such as data servers), middleware components (such as application servers), or front-end components (such as client computers having a graphical user interface or a web browser that can interact with an implementation of the subject matter described in this specification), or any combination of such back-end, middleware, and front-end components. The components of the system can be interconnected by any form or medium of digital data communication, such as a communication network. Examples of communication networks include local area networks ("LANs") and wide area networks ("WANs"), such as the Internet.

[0111] Throughout the specification and claims, language indicating approximation can be applied to quantitative expressions to modify them within an acceptable range without causing a change in the relevant basic function. Accordingly, values modified by one or more terms such as "about" and "substantially" should not be limited to the precise values described. In at least some instances, the language indicating approximation can correspond to the precision of the instrument used to measure the value. Throughout the specification and claims, the limits of ranges can be combined and / or replaced, and such ranges identify all sub-ranges included therein and include such sub-ranges unless the context or language indicates otherwise.

Claims

1. 1. An apparatus for ion accumulation comprising: a first region configured to receive ions and generate a first drive potential configured to guide the ions in a first direction across the first region; a second region configured to receive ions from the first region and to switch between a first state and a second state to generate a first electric field when in the first state and to generate a second electric field when in the second state; wherein the first electric field is configured to prevent ions from moving in the first direction into the third region and the second electric field is configured to guide ions in the first direction towards the third region; When the second region is in the first state, the first driving potential and the first electric field prevent ions in the second region from exiting the second region and cause ions to accumulate in the second region, and when the second region is in the second state, the second electric field moves ions in the first direction toward the third region.

2. The apparatus of claim 1 , wherein the first electric field is a DC voltage.

3. The apparatus of claim 2 , wherein the DC voltage magnitude is greater than the voltage bias of the first drive potential.

4. The apparatus of claim 2 , wherein the second electric field is a traveling wave.

5. The apparatus of claim 2 , wherein the magnitude of the DC voltage is less than a voltage bias of the first driving potential, the DC voltage creating a potential well.

6. The apparatus of claim 5 , wherein the second electric field is a DC potential gradient or a traveling wave.

7. 3. The apparatus of claim 2, wherein the first electric field is a traveling wave traveling in a second direction opposite the first direction, and the second electric field is a second traveling wave traveling in the first direction.

8. The apparatus of claim 1 , wherein the third region is configured to receive ions from the second region and generate a second driving potential configured to separate ions based on mobility.

9. the first region includes a plurality of electrodes disposed on a first surface, arranged along a first direction, and configured to generate a first drive potential; the second region includes one or more electrodes disposed on the first surface and arranged along a first direction and configured to generate a first electric field when in a first state and to generate a second electric field when in a second state; 2. The apparatus of claim 1.

10. Controller includes: the controller is configured to apply a first voltage signal to a plurality of electrodes in a first region, the plurality of electrodes being configured to generate a first drive potential based on the first voltage signal; The controller is configured to apply a second voltage signal to at least one electrode of the one or more electrodes in the second region, the at least one electrode being configured to generate the first electric field based on the second voltage signal; The controller controls at least one of the one or more electrodes of the second region. configured to apply a third voltage signal to the electrodes, at least one electrode configured to generate a second electric field based on the third voltage signal; When the device is in a first mode of operation, the controller applies a second voltage signal to the second plurality of electrodes to place the second region in a first state, and when the device is in a second mode of operation, the controller applies a third voltage signal to the second plurality of electrodes to place the second region in a second state.

10. The apparatus of claim 9.

11. 2. The device of claim 1 , wherein a first portion of the second region generates a first electric field when the second region is in a first state, the first portion of the second region generates a second electric field when the second region is in a second state, and the second portion of the second region generates a fourth electric field different from the first electric field.

12. 10. The device of claim 1, wherein the second region includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

13. The apparatus of claim 12 , wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

14. 1. A method for ion accumulation comprising: introducing ions into a device for ion accumulation having a first region, a second region, and a third region; generating a driving potential in the first region to steer ions in a first direction across the first region; transmitting ions from the first region to the second region with a driving potential; generating a first electric field in the second region to prevent ions from moving in the first direction into the third region; accumulating ions in a second region; and switching the first electric field generated in the second region to a second electric field to direct the accumulated ions in a first direction toward a third region.

15. The method of claim 14 , wherein the first electric field is a DC voltage.

16. The method of claim 15 , wherein the magnitude of the DC voltage is greater than the voltage bias of the driving potential.

17. The method of claim 15 , wherein the second electric field is a traveling wave.

18. The method of claim 15 , wherein the magnitude of the DC voltage is less than a voltage bias of the driving potential, and the DC voltage creates a potential well.

19. 20. The method of claim 18, wherein the second electric field is a DC potential gradient or a traveling wave.

20. 16. The method of claim 15, wherein the first electric field is a first traveling wave traveling in a second direction opposite the first direction, and the second electric field is a second traveling wave traveling in the first direction.

21. transmitting ions accumulated in the second region to a third region; generating a second drive potential in a third region; separating the ions based on their mobility using a second driving potential; The method of claim 14 further comprising:

22. the first region includes a plurality of electrodes disposed on a first surface, arranged along a first direction, and configured to generate a first drive potential; the second region includes one or more electrodes disposed on the first surface and arranged along a first direction; At least one of the one or more electrodes in the second region generates the first electric field and the second electric field. The method of claim 14.

23. 15. The method of claim 14, wherein a first portion of the second region generates a first electric field and a second electric field, and a second portion of the second region generates a fourth electric field different from the first electric field.

24. 15. The method of claim 14, wherein the second region includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

25. 25. The method of claim 24, wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays when the second region is in the first state.

26. 1. An ion storage device comprising: an ion storage section having a first width and configured to receive ions and switch between a first state and a second state to generate a first electric field when in the first state and to generate a second electric field when in the second state; an exit section having a second width less than the first width and configured to generate a third electric field configured to guide ions across the exit section; an exit transition section extending between the ion accumulation section and the exit section, the exit transition section having a tapered width decreasing from a first width adjacent the ion accumulation section to a second width adjacent the exit section, the exit transition section configured to generate a third electric field to guide ions across the exit transition section and into the exit section; wherein the first electric field is configured to prevent ions from moving in the first direction into the exit transition section and the second electric field is configured to guide ions in the first direction towards the exit transition section; When the ion accumulation section is in a first state, a first electric field prevents ions in the ion accumulation section from exiting the ion accumulation section and causes the ions to accumulate in the ion accumulation section, and when the ion accumulation section is in a second state, a second electric field moves the ions in a first direction toward the exit transition section.

27. an inlet section having a third width less than the first width; an inlet transition section extending between the entrance section and the ion accumulation section, the inlet transition section having a tapered width increasing from a third width adjacent the entrance section to a first width adjacent the ion accumulation section; wherein the entrance section and the exit transition section are configured to generate a fourth electric field to guide ions across the entrance section and the entrance transition section and into the ion accumulation section; 27. The ion storage device of claim 26.

28. 27. The ion storage device of claim 26, wherein the second electric field is a traveling wave traveling in a first direction, and the ion accumulation section is configured to switch from generating the second electric field to generate a fourth electric field, the fourth electric field being a traveling wave traveling in a second direction opposite the first direction.

29. The ion storage device of claim 26 , wherein the first electric field is a DC voltage.

30. 27. The ion storage device of claim 26, wherein a first portion of the ion storage section generates a first electric field and a second portion of the ion storage section generates a fourth electric field different from the first electric field.

31. 27. The ion storage device of claim 26, wherein the ion accumulation section includes a plurality of rows of radio frequency (RF) electrodes and a plurality of traveling wave (TW) electrode arrays, each of the plurality of TW electrode arrays including at least three individual electrodes.

32. The ion storage device of claim 31 , wherein the first electric field is generated by at least one of the individual electrodes of each of the plurality of TW electrode arrays.

33. 27. The ion storage device of claim 26, comprising an inlet section located to a side of the ion storage section, the inlet section configured to provide ions to the ion storage section.

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