Ion funnel-based collision unit

Abstract

In some examples, an ion funnel-based collision unit may include an ion funnel inlet section formed from a plurality of adjacently disposed inlet members. Each of at least one pair of adjacently disposed inlet members may include successively increasing openings to form a frustoconical or profiled inlet for ions to enter the ion funnel-based collision unit. An insulating material may be disposed adjacent to or in contact with each of the at least one pair of adjacently disposed inlet members to prevent gas flow between each of the at least one pair of adjacently disposed inlet members outside each of the successively enlarged openings.

Description

Background Art

[0001] An ion funnel can be a device for collecting ions within a mass spectrometer system. In one example, an ion funnel can include a relatively large inlet diameter and transport ions to an outlet having a relatively small outlet diameter. In one type of ion funnel, a set of stacked (e.g., parallel) plates can include openings in each plate, and the openings can be aligned along a central axis.

[0002] During operation of a mass spectrometer system, ions may enter through an inlet of relatively large diameter and exit through an outlet of relatively small diameter. Ions may move forward from the inlet to the outlet by means of an axial electric field. The axial electric field may be created by setting a direct current (DC) potential of each plate to form a downhill potential drop from the inlet to the outlet. By applying an alternating phase radio frequency (RF) voltage to the plates, ions may be prevented from impacting the walls of the ion funnel, for example, at the ring diameter or at each plate. In one example, an RF voltage and a DC voltage may be distributed from a pair of RF inputs and a pair of DC inputs to a set of plates having a resistor and capacitor ladder.

[0003] In some cases, ions can be cooled within the ion funnel by collision with a background gas, such as nitrogen. The background gas can help collect ions with relatively large input energies to deliver ions with relatively low energies at the exit. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Features of the present disclosure are illustrated by way of example and not limitation in the following drawings, in which like numerals indicate like elements, and in which:

[0005] FIG. 1 illustrates an isometric cross-sectional view of an ion funnel-based collision cell according to an example of the present disclosure, showing internal features of the ion funnel-based collision cell;

[0006] FIG. 2 illustrates a diagrammatic view showing a funnel profile of the ion funnel-based collision cell of FIG. 1 according to an example of the present disclosure;

[0007] FIG. 3 illustrates an example of an exit or internal configuration of the ion funnel-based collision cell of FIG. 1 according to an example of the present disclosure;

[0008] 4 shows various views of an ion funnel-based collision cell including multiple outlets according to an example of the present disclosure;

[0009] 5 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to an example of the present disclosure, illustrating internal features of the ion funnel-based collision cell;

[0010] 6 illustrates vacuum pressures in the inner and outer regions of the ion funnel-based collision cell of FIG. 5 using grayscale to indicate pressure changes according to an example of the present disclosure;

[0011] 7 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to an example of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement;

[0012] 8 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to an example of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement;

[0013] 9 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement; and

[0014] 10 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement. DETAILED DESCRIPTION

[0015] For the purpose of simplicity and illustration, the content of the present disclosure is mainly described by reference to examples. In the following description, many specific details are set forth to provide a comprehensive understanding of the present disclosure. However, it is easy to understand that the implementation of the present disclosure may not be limited to these specific details. In other examples, some methods and structures are not described in detail to avoid unnecessary obscurity of the present disclosure.

[0016] Throughout this disclosure, the terms "a" and "an" are intended to mean at least one of a particular element. As used herein, the term "comprising" means including but not limited to, and the term "including" means including but not limited to. The term "based on" means based at least in part on.

[0017] With respect to the ion funnel, as disclosed herein, in some cases, the ions can be cooled within the ion funnel by collision with a background gas, such as nitrogen. The background gas can help collect ions with relatively large input energies to deliver ions with relatively low energies at the outlet. Typically, the gas pressure of the background gas can include a range of about 1 Torr to 10 Torr. The pressure range can be extended, typically by increasing the RF operating frequency and amplitude, and by reducing the pressure by making the (inlet) outlet aperture to an appropriate diameter.

[0018] While various types of ion funnel implementations are available for pressures ranging from 1 to 10 Torr, ion funnel operations, including aspects of ion energy cooling, can operate at much lower pressures. Ion funnel cooling can be operational as long as the mean free path of the ions is equal to or less than the ion funnel diameter.

[0019] In the pressure range of about 3 to 100 mTorr, ion funnels can be used in place of multipole collision cells to allow ions to enter the collision cell at higher energies (e.g., 5 to 300 eV) to collide with the funnel gas, which may result in collision-induced dissociation (CID) fragmentation of the ions and include collection of fragments. In one type of ion funnel, the ions can be fragmented or separated using an annular structure in which RF is applied to achieve traveling waves. In another type of ion funnel, a static RF voltage can be used on the funnel ring. In another type of ion funnel, the funnel RF frequency and RF amplitude may need to be adjusted to support the desired mass range (e.g., in the range from mass 50 up to masses above 10,000).

[0020] The collision cell in the mass spectrometer system can surround a space with a higher pressure than other components of the mass spectrometer. In order to keep the ion mean free path relatively long, other areas in the mass spectrometer can be maintained at a pressure lower than 5e-5 Torr. However, in order to obtain enough collision energy for ion fragmentation in the CID cell, the cell pressure may need to be maintained within the range of 3-100 mTorr. Since the collision cell has an open inlet and outlet, the gas flowing out from the collision cell to the rest of the mass spectrometer system can increase the gas load pumped by the pump, and it is generally desired to be maintained at a pressure as low as possible. By keeping the inlet and outlet diameters of the collision cell relatively small (e.g., about 3 mm in diameter), the gas pressure can be kept as low as possible. At the outlet end of the collision cell, the gas leaving through the outlet aperture can be reduced by reducing the pressure in the collision cell with an internal conduction limiter. In this regard, it is technically challenging to control the gas leaving the collision cell through the ion inlet.

[0021] To address at least the above technical challenges, an ion funnel-based collision cell is disclosed herein and may include a conductance limiter at its entrance. In this regard, the conductance limiter may be placed at a relatively short distance so that the ion collision energy will not be negatively affected. The ion funnel-based collision cell may include an ion funnel used as a collision cell. The ion funnel-based collision cell may additionally form a reverse funnel at the entrance to increase the funnel diameter from a small entrance diameter toward the funnel body diameter.

[0022] For a collision cell based on an ion funnel as disclosed herein, a diverging member (e.g., a plate) at the entrance can restrict gas flow from the body of the ion funnel through the entrance lens. Further, the gas flow between the first set of funnel members can be closed by placing an insulating material around the outer diameter of the funnel entrance member to block the gas flow between these members. The inclusion of the insulating material can also minimize gas conduction from the funnel body through the entrance lens.

[0023] The diameter of the entrance member can also guide ions with initially divergent trajectories to a relatively wide funnel body without significant ion loss. Using a larger diameter ion funnel body can provide a longer cooling path length for ions that can enter the ion funnel at high collision energies (e.g., up to 300 eV). These features can allow a relatively large entrance diameter while cooling, fragmenting, and collecting fragments with relatively high overall efficiency over a wide energy range.

[0024] According to the examples disclosed herein, an ion funnel-based collision cell may include an ion funnel entrance section formed by a plurality of adjacently arranged entrance members. Each of at least one pair of adjacently arranged entrance members may include a successively larger opening to form a truncated cone or a shaped entrance for ions to enter the ion funnel-based collision cell. Tapering may provide a cross-sectional diameter that gradually increases or decreases (e.g., linearly progressively) along the central axis, and profiling may provide a cross-section of a specific shape (e.g., parabolic, hyperbolic, etc.) along the central axis. An insulating material may be arranged to be adjacent to or in contact with each of the at least one pair of adjacently arranged entrance members to prevent gas from flowing between each of the at least one pair of adjacently arranged entrance members outside each successively larger opening.

[0025] The ion funnel-based collision cell may further include an ion funnel outlet section formed by a plurality of adjacently disposed outlet components. Each outlet component of at least one pair of adjacently disposed outlet components may include a successively smaller opening to form a truncated cone or shaped outlet for ions in the ion funnel-based collision cell. The truncated cone or shaped outlet may be disposed along a central axis of the ion funnel-based collision cell.

[0026] According to examples disclosed herein, at least one inlet member of the plurality of adjacently disposed inlet members may be at least partially formed as a plate.

[0027] According to another example, an ion funnel-based collision cell may include an ion funnel inlet section formed by a plurality of adjacently arranged inlet components. Each of at least one pair of adjacently arranged inlet components may include an opening that becomes larger successively. An insulating barrier (e.g., comprising an insulating material or another type of barrier) may be arranged adjacent to or in contact with each of the inlet components of the at least one pair of adjacently arranged inlet components to control the gas flow in the ion funnel-based collision cell.

[0028] As disclosed in detail in a co-pending patent application entitled “MULTIPOLE SECTION-BASED ION FUNNE,” filed on July 29, 2022, the disclosure of which is incorporated by reference in its entirety, the ion funnel-based collision cell (which can be designated as a multipole segment-based ion funnel based on the configuration of the inlet, outlet, and associated features) can include at least one pair of adjacently disposed components at a truncated cone or shaped outlet. The first component of the at least one pair of adjacently disposed components can include a pole structure. In addition, the second component of the at least one pair of adjacently disposed components can include a pole structure that can be engaged with the pole structure of the first component to form a multipole structure. The pole structure of the first component and the pole structure of the second component can form at least two poles. For example, the pole structure of the first component and the pole structure of the second component can form a quadrupole, a hexapole, or the like.

[0029] According to examples disclosed herein, a truncated cone (or shaped) inlet and / or a truncated cone (or shaped) outlet may include a circular cross-section. Alternatively, a truncated cone (or shaped) inlet and / or a truncated cone (or shaped) outlet may include a non-circular cross-section. In one example, the truncated cone outlet may be radially offset relative to the central axis of the ion funnel-based collision cell. In this regard, one of the outlets may be eliminated so that a single outlet is radially offset relative to the central axis of the ion funnel-based collision cell.

[0030] The ion funnel-based collision cell may further include an ion funnel outlet section formed by a plurality of adjacently disposed outlet components. Each outlet component of at least one pair of adjacently disposed outlet components may include a plurality of successively smaller openings to form a plurality of truncated cone-shaped outlets for ions in the ion funnel-based collision cell. The reduced diameter outlets may have the same or different sizes to allow, for example, ions of different sizes to pass through outlets of different sizes of the ion funnel-based collision cell.

[0031] The ion funnel entrance section can be formed by a plurality of adjacently arranged entrance members. Each entrance member in at least one pair of adjacently arranged entrance members can include an opening that becomes larger successively to form a truncated cone or a profiled entrance for ions to enter a collision unit based on an ion funnel. In addition, each entrance member in the at least one pair of adjacently arranged entrance members can include a specific shape to prevent gas from flowing between each entrance member in the at least one pair of adjacently arranged entrance members outside each opening that becomes larger successively. The specific shape can include an orthogonal wall protruding from a flat inner plate (or an annular arrangement of angled or herringbone stacking for suppressing radial gas expansion in the region). Alternatively, the specific shape can include any other shape to prevent gas from flowing between each entrance member in the at least one pair of adjacently arranged entrance members outside each opening that becomes larger successively. In another example, an insulating material can be arranged between adjacently arranged entrance members to prevent gas from flowing between each entrance member in the at least one pair of adjacently arranged entrance members.

[0032] The ion funnel-based collision cell may further include an ion funnel exit section formed by a plurality of adjacently disposed exit members. Each exit member of at least one pair of adjacently disposed exit members may include successively smaller openings to form a frustoconical exit for ions in the ion funnel-based collision cell.

[0033] Figure 1 shows an isometric cross-sectional view of an ion funnel-based collision cell 100 according to an example of the present disclosure, showing internal features of the ion funnel-based collision cell. Figure 2 shows a diagrammatic view showing a funnel profile of the ion funnel-based collision cell 100 according to an example of the present disclosure.

[0034] 1 and 2, an ion funnel-based collision cell 100 may include an ion funnel entrance section 102 formed by a plurality of adjacently disposed entrance members 104-1, 104-2, ..., 104-n. Each of at least one pair of adjacently disposed entrance members 104-1, 104-2, ..., 104-n may include successively larger openings 106-1, 106-2, ..., 106-n to form a truncated cone-shaped entrance 108 (or a shaped entrance) for ions to enter the ion funnel-based collision cell 100. An insulating material 110 may be disposed adjacent to or in contact with each of at least one pair of adjacently disposed entrance members 104-1, 104-2, ..., 104-n to prevent gas from flowing between each of the at least one pair of adjacently disposed entrance members 104-1, 104-2, ..., 104-n outside each successively larger opening.

[0035] 1, insulating material 110 may be placed around the outer diameter of the funnel components to block airflow between those components. Thus, based on the use of insulating material 110, gas conduction from the funnel body through the entrance lens may be further minimized.

[0036] As shown in Figure 1, the diameter of the entrance member can help guide ions with initially divergent trajectories to a wider funnel body without significant ion loss. Using a larger diameter funnel body can allow for a longer cooling path length for ions that can enter the funnel at high collision energies (e.g., up to 300 eV). This combination can allow for a relatively large entrance diameter while cooling, fragmenting, and collecting fragments with a higher overall efficiency over a wide energy range.

[0037] The ion funnel-based collision cell 100 may further include an ion funnel exit section 112 formed by a plurality of adjacently disposed exit components 114-1, 114-2, ..., 114-n. Each of at least one pair of adjacently disposed exit components 114-1, 114-2, ..., 114-n may include successively smaller openings 118-1, 118-2, ..., 118-n to form a truncated cone-shaped exit 120 for ions in the ion funnel-based collision cell 100. The truncated cone-shaped exit 120 may be disposed along a central axis 116 of the ion funnel-based collision cell 100.

[0038] According to examples disclosed herein, at least one of the plurality of adjacently disposed inlet members 104 - 1 , 104 - 2 , . . . , 104 - n may be at least partially formed as a plate.

[0039] According to another example, the ion funnel-based collision cell 100 may include an ion funnel entrance section 102 formed by a plurality of adjacently arranged entrance components 104-1, 104-2, ..., 104-n. Each of at least one pair of adjacently arranged entrance components 104-1, 104-2, ..., 104-n may include successively larger openings 106-1, 106-2, ..., 106-n. An insulating barrier (e.g., including an insulating material 110) may be disposed adjacent to or in contact with each of the at least one pair of adjacently arranged entrance components 104-1, 104-2, ..., 104-n to control gas flow in the ion funnel-based collision cell 100.

[0040] As disclosed in detail in a co-pending patent application entitled “MULTIPOLE SECTION-BASED ION FUNNE,” filed on July 29, 2022, the disclosure of which is incorporated by reference in its entirety, the ion funnel-based collision cell 100 (which may be designated as a multipole segment-based ion funnel based on the configuration of the inlet, outlet, and associated features) may include at least one pair of adjacently disposed components 122-1, 122-2, etc. at a truncated cone-shaped outlet 120. In the example of FIG. 1 , three pairs of adjacently disposed components are shown. The first component (e.g., 122-1) of the at least one pair of adjacently disposed components may include a pole structure. In addition, the second component (e.g., 122-2) of the at least one pair of adjacently disposed components may include a pole structure that may be engaged with the pole structure of the first component to form a multipole structure. The pole structure of the first component 122-1 and the pole structure of the second component 122-2 may form at least two poles. For example, the rod structure of the first component 122 - 1 and the rod structure of the second component 122 - 2 may form a quadrupole, a hexapole, or the like.

[0041] FIG. 3 illustrates an example of an exit or internal configuration of an ion funnel based collision cell 100 according to an example of the present disclosure.

[0042] 3, various options for the internal cross-section of a single inlet or outlet of an ion funnel-based collision cell 100 are shown, as shown at 300. Various options for the internal cross-section of multiple inlets or outlets of an ion funnel-based collision cell 100 are shown at 302. Examples at 300 and 302 may include a flat plate (e.g., at 124 in FIG. 1), a mixture of a flat plate and one or more pairs of adjacently disposed members 122-1, 122-2, etc., or only one or more pairs of adjacently disposed members 122-1, 122-2, etc.

[0043] FIG. 4 illustrates various views of an ion funnel-based collision cell 420 including multiple outlets according to examples of the present disclosure.

[0044] 1 and 4, the truncated cone-shaped inlet 108 and / or the truncated cone-shaped outlet 120 may include a circular cross-section. Alternatively, the truncated cone-shaped inlet 108 and / or the truncated cone-shaped outlet 120 may include a non-circular cross-section. In one example, the truncated cone-shaped outlet may be radially offset relative to the central axis 116 of the ion funnel-based collision cell 100 (e.g., as shown in FIG. 4, which shows two outlets). In this regard, one of the outlets may be eliminated so that the single outlet is radially offset relative to the central axis 116 of the ion funnel-based collision cell 100.

[0045] 4, the ion funnel-based collision cell 420 may further include an ion funnel exit section 400 formed by a plurality of adjacently disposed exit components 402-1, 402-2, ..., 402-N. Each of at least one pair of adjacently disposed exit components 402-1, 402-2, ..., 402-N may include a plurality of successively smaller openings 404-1, 404-2, 404-3, 404-4, 404-5, ..., 404-N to form a plurality of truncated cone-shaped exits 406-1 and 406-2 for ions in the ion funnel-based collision cell 420.

[0046] Figure 5 shows a diagrammatic side view of another example of an ion funnel-based collision cell 500 according to an example of the present disclosure, showing internal features of the ion funnel-based collision cell 500. Figure 6 shows vacuum pressure in the interior and exterior regions of the ion funnel-based collision cell 500 using grayscale to indicate pressure changes according to an example of the present disclosure.

[0047] 5 and 6, the ion funnel entrance section 502 may be formed by a plurality of adjacently arranged entrance components 504-1, 504-2, ..., 504-N. Each of at least one pair of adjacently arranged entrance components 504-1, 504-2, ..., 504-N may include successively larger openings 506-1, 506-2, ..., 506-N to form a truncated cone-shaped entrance 508 (or a shaped entrance) for ions to enter the ion funnel-based collision cell 500. In addition, each of the at least one pair of adjacently disposed inlet members (504-1, 504-2, ..., 504-N) may include a specific shape (e.g., at 510-1, 510-2, ..., 510-N) to prevent gas from flowing between each of the at least one pair of adjacently disposed inlet members 504-1, 504-2, ..., 504-N outside each successively larger opening 506-1, 506-2, ..., 506-N (e.g., at 512-1, 512-2, ..., 512-N). In the example of FIG. 5, the specific shape (e.g., at 510-1, 510-2, ..., 510-N) may include orthogonal walls protruding from a flat inner plate (or an angled or herringbone stacked annular arrangement to inhibit radial gas expansion in this area).

[0048] In general, the ion funnel-based collision cell 500 may not be limited to having a cylindrically symmetrical design, but may have virtually any internal shape, including shapes with multiple inlets and / or outlets, or where the funnel channel 126 follows an arbitrary nonlinear path. The insulating conductive limiter imposed by the insulating material 110 may be replaced or enhanced with a shaped metal member as shown. Replacing the insulating material 110 with a shaped metal member may reduce the risk of charging (e.g., charge accumulation on the dielectric surface).

[0049] Continuing to refer to FIGS. 5 and 6 , the gas flow in the ion funnel-based collision cell 500 is shown at 600. In this regard, the gas can flow between the wall 602 and the components 604 and 606. However, due to the orthogonal walls at 510-1, 510-2, ..., 510-N, the gas flow can be restricted to the internal region 608 of the ion funnel-based collision cell 500. The gas pressure can be relatively high at 610 (e.g., millitorr range) and relatively low at 612 (e.g., 1e-5 torr range). At relatively low pressures and small spaces, the flow can include molecular flow characteristics. In this regard, most gas molecules can travel in a straight line from one surface to the next surface with relatively few gas-gas collisions, which may tend to reduce effective conduction compared to higher pressure flows.

[0050] 1 and 5, the ion funnel-based collision cell 500 may further include an ion funnel exit section 112 formed by a plurality of adjacently disposed exit components (e.g., as shown in FIG. 1). Each of at least one pair of adjacently disposed exit components 114-1, 114-2, ..., 114-n may include successively smaller openings 118-1, 118-2, ..., 118-n to form a truncated cone-shaped exit 120 for ions in the ion funnel-based collision cell 500.

[0051] In one example, the frustoconical inlet 508 and / or the frustoconical outlet 120 may include a circular cross-section (eg, see FIGS. 1 and 3 ). In another example, the frustoconical inlet 508 and / or the frustoconical outlet 120 may include a non-circular cross-section (eg, see FIGS. 1 and 3 ).

[0052] In one example, the frustoconical outlet can be radially offset relative to the central axis 514 of the ion funnel-based collision cell 500 (e.g., in a manner similar to that shown in FIG. 4 showing two outlets). In this regard, one of the outlets can be eliminated such that the single outlet is radially offset relative to the central axis 514 of the ion funnel-based collision cell 500.

[0053] 4 and 5, the ion funnel-based collision cell 500 may further include an ion funnel exit section 400 formed by a plurality of adjacently disposed exit components 402-1, 402-2, ..., 402-N (e.g., in a manner similar to that shown in FIG. 4). Each of at least one pair of adjacently disposed exit components 402-1, 402-2, ..., 402-N may include a plurality of successively smaller openings 404-1, 404-2, 404-3, 404-4, 404-5, ..., 404-N to form a plurality of truncated cone-shaped exits 406-1, 406-2 for ions in the ion funnel-based collision cell 500.

[0054] 7 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell 700 according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement.

[0055] With reference to Fig. 7, the ion funnel entrance section 702 can be formed by a plurality of adjacently arranged entrance members 704-1, 704-2, ..., 704-N. Each of the adjacently arranged entrance members 704-1, 704-2, ..., 704-7 can include an opening that becomes larger successively from 706-1 toward 706-N to form a profiled entrance 708 for ions to enter the collision cell 700 based on the ion funnel. In addition, each of the adjacently arranged entrance members 704-1, 704-2, ..., 704-N can include a specific shape as shown to prevent gas from flowing between each of the adjacently arranged entrance members 704-1, 704-2, ..., 704-N. In the example of Fig. 7, a specific shape (e.g., at 710-1, 710-2, ..., 710-3, etc.) can include an angled or herringbone stacked entrance member arrangement for suppressing radial gas expansion. For example, the angle at 710-1, etc. can be oriented toward the entrance of the collision cell 700 based on the ion funnel (e.g., the left side of Figure 7, in the orientation of Figure 7). The geometry of the entrance member can be used to help the forward movement of ions by acceleration, or to hinder the movement of ions by deceleration. For example, the geometry at 710-1, etc. can provide a push (e.g., acceleration) field to help the forward movement of ions. The geometry of the entrance member 704-1, 704-2, ..., 704-N can also provide radial gas flow restrictions for gases flowing in the direction indicated by arrow 712. In addition, a lens element 714 can be provided to form an entrance hole 716 as shown.

[0056] 8 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell 800 according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement.

[0057] With reference to FIG8, the ion funnel entrance section 802 can be formed by a plurality of adjacently arranged entrance members 804-1, 804-2, ..., 804-N. Each of the adjacently arranged entrance members 804-1, 804-2, ..., 804-8 can include an opening that becomes larger successively from 806-1 toward 806-N to form a profiled entrance 808 for ions to enter the collision cell 800 based on the ion funnel. In addition, each of the adjacently arranged entrance members 804-1, 804-2, ..., 804-N can include a specific shape as shown to prevent gas from flowing between each of the adjacently arranged entrance members 804-1, 804-2, ..., 804-N. In the example of FIG8, a specific shape (e.g., at 810-1, 810-2, ..., 810-3, etc.) can include an angled or herringbone stacked entrance member arrangement for suppressing radial gas expansion. For example, the angle at 810-1 etc. can be oriented toward the entrance of the collision cell 800 based on the ion funnel (e.g., the left side of FIG. 8, in the orientation of FIG. 8). Compared with the collision cell 700 based on the ion funnel of FIG. 7, the collision cell 800 based on the ion funnel can include an entrance of a larger diameter at 812. The geometry of the entrance member can be used to help the forward motion of ions by accelerating, or to hinder the motion of ions by decelerating. For example, the geometry at 810-1 etc. can provide a push (e.g., acceleration) field to help the forward motion of ions. The geometry of the entrance member 804-1, 804-2, ..., 804-N can also provide radial gas flow restrictions for the gas flowing in the direction indicated by the arrow 814. In addition, a lens element 816 can be provided to form an entrance hole 818 as shown.

[0058] 9 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell 900 according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement.

[0059] With reference to FIG9 , the ion funnel entrance section 902 can be formed by a plurality of adjacently arranged entrance members 904-1, 904-2, ..., 904-N. Each of the adjacently arranged entrance members 904-1, 904-2, ..., 904-9 can include an opening that becomes larger successively from 906-1 toward 906-N to form a profiled entrance 908 for ions to enter the collision cell 900 based on the ion funnel. In addition, each of the adjacently arranged entrance members 904-1, 904-2, ..., 904-N can include a specific shape as shown to prevent gas from flowing between each of the adjacently arranged entrance members 904-1, 904-2, ..., 904-N. In the example of FIG9 , a specific shape (e.g., at 910-1, 910-2, ..., 910-3, etc.) can include an angled or herringbone stacked entrance member arrangement for suppressing radial gas expansion. For example, the angle at 910-1, etc. can be oriented away from the entrance of the collision cell 900 based on the ion funnel (e.g., the left side of Figure 9, in the orientation of Figure 9). The geometry of the entrance member can be used to help the forward motion of the ions by accelerating, or to hinder the motion of the ions by decelerating. For example, the geometry at 910-1, etc. can provide a stopping (e.g., decelerating) field to hinder the motion of the ions. The geometry of the entrance members 904-1, 904-2, ..., 904-N can also provide radial gas flow restrictions for the gas flowing in the direction indicated by the arrow 912. In addition, a lens element 914 can be provided to form an entrance hole 916 as shown.

[0060] 10 illustrates a diagrammatic side view of another example of an ion funnel-based collision cell according to examples of the present disclosure, illustrating internal features of the ion funnel-based collision cell for providing a profiled inlet and gas confinement.

[0061] 10, the ion funnel entrance section 1002 can be formed by a plurality of adjacently arranged entrance components 1004-1, 1004-2, ..., 1004-N. Each of the adjacently arranged entrance components 1004-1, 1004-2, ..., 1004-10 can include openings that are successively larger from 1006-1 toward 1006-N to form a shaped entrance 1008 for ions to enter the ion funnel-based collision cell 1000. The shaped entrance 1008 can be described as a shaped cone (e.g., an irregular nonlinear cone) having openings at different angles, as shown at 1006-1, 1010, etc. In addition, an insulating material 1012 can be used to suppress radial gas expansion.

[0062] What has been described and illustrated herein are examples and some variations thereof. The terms, descriptions, and figures used herein are set forth by way of illustration only and are not meant to be limiting. Many variations are possible within the spirit and scope of the subject matter, which is intended to be defined by the following claims and their equivalents, wherein all terms are to be interpreted in their broadest reasonable sense unless otherwise indicated.

Claims

1. A collision cell based on an ion funnel, comprising: an ion funnel entrance section formed by a plurality of adjacently arranged entrance components, wherein each of at least one pair of adjacently disposed inlet members comprises an opening that is successively larger to form a truncated cone or shaped inlet for ions to enter the ion funnel-based collision cell; and An insulating material is disposed adjacent to or in contact with each of the at least one pair of adjacently disposed inlet members to prevent gas flow between each of the at least one pair of adjacently disposed inlet members outside of each successively larger opening.

2. The ion funnel-based collision cell of claim 1 , further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Each of the at least one pair of adjacently disposed outlet components comprises a successively smaller opening to form a truncated cone or shaped outlet for ions in the ion funnel-based collision cell.

3. The ion funnel-based collision cell of claim 2, wherein: At least one of the frustoconical or shaped inlet or the frustoconical or shaped outlet comprises a circular cross-section.

4. The ion funnel-based collision cell of claim 2, wherein: At least one of the frustoconical or shaped inlet or the frustoconical or shaped outlet comprises a non-circular cross-section.

5. The ion funnel-based collision cell of claim 2, wherein: The truncated cone or profiled outlet is disposed along a central axis of the ion funnel-based collision cell.

6. The ion funnel-based collision cell of claim 2, wherein: The frustoconical or shaped outlet is radially offset relative to a central axis of the ion funnel-based collision cell.

7. The ion funnel-based collision cell of claim 1 , further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Each of at least one pair of adjacently disposed outlet components comprises a plurality of successively smaller openings to form a plurality of truncated cone-shaped or shaped outlets for ions in the ion funnel-based collision cell.

8. The ion funnel-based collision cell of claim 1, wherein: At least one inlet member of the plurality of adjacently disposed inlet members is at least partially formed as a plate.

9. A collision cell based on an ion funnel, comprising: an ion funnel entrance section formed by a plurality of adjacently arranged entrance components, wherein each of at least one pair of adjacently disposed inlet members comprises an opening that is successively larger to form a truncated cone or shaped inlet for ions to enter the ion funnel-based collision cell, and Wherein, each of the at least one pair of adjacently disposed inlet components comprises a specific shape to prevent gas from flowing between each of the at least one pair of adjacently disposed inlet components outside each successively larger opening.

10. The ion funnel-based collision cell of claim 9, wherein: The particular shape includes orthogonal walls protruding from a flat inner panel.

11. The ion funnel-based collision cell of claim 9, wherein: The specific shape includes angled walls to inhibit radial gas expansion.

12. The ion funnel-based collision cell of claim 9, further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Each of the at least one pair of adjacently disposed outlet components comprises a successively smaller opening to form a truncated cone or shaped outlet for ions in the ion funnel-based collision cell.

13. The ion funnel-based collision cell of claim 12, wherein: At least one of the frustoconical or shaped inlet or the frustoconical or shaped outlet comprises a circular cross-section.

14. The ion funnel-based collision cell of claim 12, wherein: At least one of the frustoconical or shaped inlet or the frustoconical or shaped outlet comprises a non-circular cross-section.

15. The ion funnel-based collision cell of claim 12, wherein: The truncated cone or profiled outlet is disposed along a central axis of the ion funnel-based collision cell.

16. The ion funnel-based collision cell of claim 12, wherein: The frustoconical or shaped outlet is radially offset relative to a central axis of the ion funnel-based collision cell.

17. The ion funnel-based collision cell of claim 9, further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Each of at least one pair of adjacently disposed outlet components comprises a plurality of successively smaller openings to form a plurality of truncated cone-shaped or shaped outlets for ions in the ion funnel-based collision cell.

18. A collision cell based on an ion funnel, comprising: an ion funnel entrance section formed by a plurality of adjacently arranged entrance components, wherein each of at least one pair of adjacently disposed inlet members comprises an opening that becomes successively larger; and An insulating barrier is disposed adjacent to or in contact with each of the at least one pair of adjacently disposed inlet members to control gas flow in the ion funnel-based collision cell.

19. The ion funnel-based collision cell of claim 18, further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Wherein, each outlet member of at least one pair of adjacently arranged outlet members comprises an opening that becomes smaller successively.

20. The ion funnel-based collision cell of claim 18, further comprising: an ion funnel outlet section formed by a plurality of adjacently arranged outlet components, Wherein, each outlet component of at least one pair of adjacently arranged outlet components comprises a plurality of openings which become smaller successively.

21. The ion funnel-based collision cell of claim 18, wherein: At least one inlet member of the plurality of adjacently disposed inlet members is at least partially formed as a plate.

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