(19)
(11)EP 3 096 327 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
08.05.2019 Bulletin 2019/19

(21)Application number: 16159281.1

(22)Date of filing:  08.03.2016
(51)Int. Cl.: 
G21K 1/00  (2006.01)
G06N 99/00  (2019.01)
H01L 29/94  (2006.01)
B82Y 10/00  (2011.01)
H01J 49/00  (2006.01)
H01J 49/42  (2006.01)

(54)

ION TRAP WITH VARIABLE PITCH ELECTRODES

IONENFALLE MIT ELEKTRODEN UNTERSCHIEDLICHER TEILUNG

PIÈGE À IONS AVEC DES ÉLECTRODES À PAS VARIABLE


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 22.05.2015 US 201514719587

(43)Date of publication of application:
23.11.2016 Bulletin 2016/47

(73)Proprietor: Honeywell International Inc.
Morris Plains, NJ 07950 (US)

(72)Inventor:
  • YOUNGNER, Daniel
    Morris Plains, NJ 07950 (US)

(74)Representative: Houghton, Mark Phillip 
Patent Outsourcing Limited 1 King Street
Bakewell, Derbyshire DE45 1DZ
Bakewell, Derbyshire DE45 1DZ (GB)


(56)References cited: : 
EP-A2- 0 884 785
WO-A1-2014/195677
WO-A1-2013/063660
US-A1- 2006 169 882
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Statement of Government Rights



    [0001] This invention was made with Government support under contract: W911NF-12-1-0605, awarded by the U.S. Army. The Government has certain rights in this invention.

    Technical Field



    [0002] The present disclosure relates to methods, devices, and systems for positional control of ions in an ion trap.

    Background



    [0003] An ion trap can use a combination of electrical and magnetic fields to capture one or more ions in a potential well. Ions can be trapped for a number of purposes, which may include mass spectrometry, research, and/or controlling quantum states, for example.

    [0004] Ions can be transported along a path in some regions of an ion trap, and can have their motion restricted in other regions of an ion trap. As an example, electric and/or magnetic fields can be used to transport and/or capture ions (e.g., charged particles). Some ion traps make use of electrodes to transport and/or capture ions, for example, by providing static and/or oscillating electric fields that can interact with the ion.

    [0005] It may be desirable to provide differing degrees of positional control to such ions as they move through different regions of an ion trap; however, providing differing degrees of positional control over ions in an ion trap can be problematic using conventional methods, which can employ electrodes of uniform pitch to provide positional control.

    [0006] United States Patent Application US2006/0169882 discloses a planar ion trap with RF electrodes and static voltage electrodes.

    [0007] International Patent Application Publication WO2014/195677 discloses a device with two sets of concentric ring electrodes that become progressively shorter in the longitudinal direction as one moves away from the front end.

    [0008] European Patent Application Publication EP0884785 A2 discloses a vertical transistor used in a memory cell, having a trench capacitor.

    [0009] International Patent Publication No. WO 2013/063660 describes an ion guide for a mass spectrometer, the guide having a shaped end designed to funnel the ions towards the axis of the guide.

    Summary of the Invention



    [0010] The present provides for an ion trap as claimed in the accompanying claims.

    Brief Description of the Drawings



    [0011] 

    Figure 1 provides an illustration of an example ion trap.

    Figure 2 illustrates a portion of an example ion trap.

    Figure 3 illustrates an example flow chart of an example method for providing an ion trap with variable pitch electrodes.


    Detailed Description



    [0012] The embodiments of the present disclosure relate to methods, apparatuses, and systems for design, fabrication, and use of an ion trap with variable pitch electrodes. As described herein, different issues which can arise from the use of some previous approaches to ion trap technology can be overcome.

    [0013] One such issue can arise from use of electrodes that are formed on uniform pitch in an ion trap. Forming electrodes on uniform pitch in an ion trap can limit positional control over ions in an ion trap, for example, by providing a uniform electric field that can interact with the ion. Stated differently, positional control of ions in an ion trap can be limited to a single degree of positional control over the ions if the ions are transported and/or positioned using electrodes that are formed on uniform pitch.

    [0014] In the following detailed description, reference is made to the accompanying figures that form a part hereof. The figures show by way of illustration how one or more embodiments of the disclosure may be practiced.

    [0015] The embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice one or more embodiments of this disclosure. It is to be understood that other embodiments may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the present disclosure.

    [0016] As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, combined, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. The proportion and the relative scale of the elements provided in the figures are intended to illustrate the embodiments of the present disclosure, and should not be taken in a limiting sense. It should be noted that although many of the figures provided herein provide visual views of example optical bench configurations and example alignments of optical fibers, the embodiments of the present disclosure can be accomplished by using different configurations, materials, and/or components. Further, as used herein, "a" or "a number of" something can refer to one or more such things. For example, "a number of optical components" can refer to one or more optical components. Figure 1 provides an illustration of an example ion trap 100 according to the present disclosure. As illustrated in Figure 1, the ion trap 100 can include a plurality of vias 109-1, 109-2, ..., 109-N (referred to generally herein as "vias 109"). A plurality of capacitors 110-1, 110-2, ..., 110-N (referred to generally herein as "capacitors 110") is included and positioned such that a respective capacitor 110-1, for example radially encompasses a respective via 109-1, for example. The ion trap 100 can be fabricated using anisotropic and deep reactive ion (DRIE) etching techniques, among other suitable techniques.

    [0017] The plurality of capacitors 110 are formed on a first pitch 120-1. As used herein, "pitch" refers to a distance between various similar objects. For example, as illustrated in Figure 1, a first capacitor (e.g., 110-1) can be formed adjacent to a second capacitor (e.g., 110-2), and the distance (e.g., first pitch 120-1) between the two capacitors in the x-direction is then the pitch on which the two capacitors 110-2, 110-2 are formed. As a further example, a pitch (e.g., 122-1) associated with electrodes (e.g., 112-1, 112-2) can be a distance between the rails of the electrodes.

    [0018] In the example of Figure 1, the ion trap 100 includes a first region 114 and a second region 116. According to the invention, first region 114 can include a plurality of vias 109 and includes a plurality of capacitors 110. The second region 116 includes a plurality of electrodes 112-1, 112-1, ..., 112-N (referred to generally herein as "electrodes 112"),and a control region 118.

    [0019] In some embodiments, respective electrodes among the plurality of electrodes 112 can be formed on a pitch that is different from the first pitch 120. For example, electrode 112-2 can be formed on a second pitch 122-1 that is different from the first pitch 120-1. As a further example, electrodes 120-N can be formed on a pitch 122-N that is different than the first pitch 120-1. Examples are not so limited; however, and respective electrodes of the plurality of electrodes 112 can be formed at a pitch that is different both from the first pitch 120-1 and a pitch (e.g., 122-1) on which a different respective electrode is formed. That is, electrode 112-N can be formed on a pitch 122-N that is different than the first pitch 120-1 and different from pitch 122-1, for example.

    [0020] According to the invention, the pitch of respective electrodes of the plurality of electrodes 112 varies along a length of a respective electrode (e.g., 112-1). For example, in the first region 114, an electrode 112-1 can have a pitch that is the same as the first pitch 120-1, and a pitch that is different than the first pitch 120-1 in the second region 116. In some embodiments, the rails of a respective electrode 112 can taper continuously from the first pitch to the second pitch.

    [0021] According to the invention the ion trap 100 includes a plurality of variable pitch electrodes 112 disposed on the ion trap 100. A respective electrode (e.g., 112-1) of the plurality of electrodes 112 has a first pitch 121-1 in a first region 114 of the ion trap 100 and a second pitch 122-1 in a second region 116 of the ion trap 100.

    [0022] A plurality of capacitors 110 is disposed in the first region 114. According to the invention, a respective capacitor (e.g., 110-1) of the plurality of capacitors 110 is formed on the first pitch 120-1. The capacitors 110 can be trench capacitors, for example.

    [0023] In some embodiments, the first pitch can be between 50 microns and 70 microns, and the second pitch can be less than 50 microns. Embodiments are not so limited; however, and the second pitch can be greater than 70 microns, for example.

    [0024] As discussed in further detail in connection with Figure 2, providing electrodes 112 on a different pitch (e.g., 121-1, ..., 121-N, 122-1, ..., 122-N) than a pitch 120-1 associated with the capacitors 110 can allow for ions to be transported with varying degrees of positional control in the ion trap 100. For example, coarse positional control over ions in the ion trap 100 can be provided in a first region 114, while fine positional control over ions in the ion trap 100 can be provided in a second region 116.

    [0025] Figure 2 illustrates a portion of an example ion trap 200 according to the present disclosure. According to the invention, a pitch on which a respective electrode (e.g., 212-1) is formed varies along a length of the respective electrode (e.g., 212-1). That is, the pitch of a respective electrode (e.g., 212-1) is tapered such that a pitch at one end of the electrode (e.g., 212-1) is different than a pitch at the opposite end of the electrode (e.g., 212-1). For example, with respect to electrode 212-1, pitch 221-1 can be different than pitch 220-1, and can also be different than pitch 222-1.

    [0026] In some embodiments, the capacitors 210 can be trench capacitors. As an example, trench capacitors 210 can be formed such that a trench region of at least one of the plurality of capacitors 210 extends to a depth of between 200 and 400 microns from the surface of the ion trap. In some embodiments, at least one of the plurality of capacitors 210 can have a capacitance between 50 and 250 picofarads. For example, at least one of the capacitors 210 can have a capacitance of 100 picofarads.

    [0027] In some embodiments, an ion trap apparatus can include an apparatus body, a plurality of vias 209 disposed on the body, and a plurality of electrodes 212. Each respective electrode (e.g., 212-1) is electrically coupled to a respective capacitor (e.g., 210-2). A first pitch 220-1 of each respective electrode 212 can be the same as a pitch 220-1 of the respective capacitor (e.g., 210-2) in a first region 214 of the body, and a second pitch (e.g., 222-1) of each respective electrode 212 is different than the pitch 220 of the respective capacitor 210 in a second region 216 of the body. Advantageously, this can allow for variable positional control of an ion in the different regions. For example, coarse positional control can be provided in first region 214, and fine positional control can be provided in second region 216 and in the control region 218.

    [0028] According to the invention, the pitch of a respective electrode (e.g., 212-1) is tapered from the first pitch 220-1 to the second pitch 222-1 such that a distance between the rails of the respective electrode (e.g., 212-1) changes as a distance from the respective capacitor (e.g., 210-2) changes.

    [0029] An example method 330 of fabrication for one or more embodiments contained herein is presented below. In some embodiments, an ion trap can be formed from a plurality of alternating metal and dielectric layers that can be formed together in a sequential order. For instance, anisotropic etching or deep reactive ion etching (DRIE) can be used to form portions of the ion trap. Anisotropic etching and DRIE are different etching techniques in the context of device fabrication.

    [0030] Figure 3 illustrates an example flow chart of an example method 330 for forming an ion trap with variable pitch electrodes. In this embodiment, the process can include forming a plurality of vias through an ion trap apparatus, at block 332. For example, in the embodiment of Figure 2, the ion trap includes a plurality of vias 209 that can be formed through the substrate.

    [0031] At block 334, the method 330 includes forming a plurality of capacitors in the ion trap apparatus such that a respective via (e.g., 209) is substantially encircled by a respective capacitor (e.g., 210-1) of the plurality of capacitors 210. In some embodiments at least one of the capacitors can be a trench capacitor.

    [0032] In various embodiments, the method 330 can include forming a plurality of electrodes, wherein a respective electrode is electrically coupled to the respective capacitor of the plurality of capacitors, and wherein the respective electrode is formed at a first pitch in a first region of the ion trap apparatus and is formed at a second pitch in a second region of the ion trap apparatus. In some embodiments, a pitch associated with a respective electrode can taper from the first pitch to the second pitch such that a distance between the rails of the electrodes changes as a distance from a respective capacitor changes.

    [0033] The method 330 can also include forming at least one of the plurality of capacitors to a depth between 250 and 350 microns below a surface of the ion trap apparatus. In some embodiments, the method can include filling a trench region of at least one of the plurality of capacitors with a doped polysilicon material. For example, the sidewalls of at least one of the plurality of capacitors can be oxidized and subsequently filled with a polysilicon. In some embodiments, the polysilicon can be a boron-doped polysilicon, for example 1.0 × 1025m-3 boron-doped polysilicon.

    [0034] In some embodiments, the method 330 can include forming the plurality of electrodes out of a metal, e.g., gold or other suitable metal. The electrodes can be formed such that a width of a respective rail of an electrode is between 1 micron and 2 microns.

    [0035] The method 330 can include controlling a position of an ion in the ion trap with a first level of positional control in the first region of the trap, and controlling the position of an ion in the ion trap with a second level of positional control in the second region of the trap. In some embodiments, the first level of positional control and the second level of positional control can be different. For example, a comparatively coarse level of positional control over the ion can be provided in the first region of the trap and a comparatively fine level of positional control over the ion can be provided in the second region of the trap.

    [0036] Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art will appreciate that any arrangement calculated to achieve the same techniques can be substituted for the specific embodiments shown. The scope of the invention is defined in the appended claims.

    [0037] It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combination of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description.

    [0038] In the foregoing Detailed Description, various features are grouped together in example embodiments illustrated in the figures for the purpose of streamlining the disclosure. Rather,inventive subject matter lies in less than all features of a single disclosed embodiment.


    Claims

    1. An ion trap (100) comprising:

    a plurality of capacitors (110-N) in a first region (114) of the trap arranged having a first pitch;

    a plurality of electrodes (112-N) electrically coupled to a respective capacitor (110-N) in the first region (114),

    characterised by at least some of the electrodes (112-N) being tapered in a second region (116) of the trap such that the pitch of at least some of the electrodes (112-N) in the second region (116) is different from the first pitch.


     
    2. The ion trap (100) of claim 1, wherein the capacitors (110-1, 110-2, 110-N, 210-1, 210-2, 210-N) are trench capacitors.
     
    3. The ion trap (100) of claim 1, wherein the first pitch (121-N) is between 50 microns and 70 microns.
     
    4. The ion trap (100) of claim 1, wherein the pitch between tapered electrodes in the second region (116) of the trap varies to less than 50 microns.
     
    5. The ion trap (100) of claim 1, wherein the pitch between tapered electrodes in the second region (116) of the trap increases to greater than 70 microns.
     
    6. The ion trap (100, 200) of claim 1, wherein the tapered electrodes (112-N) taper continuously in the second region (116) of the trap.
     
    7. The apparatus of claim 1, wherein the width of the electrodes (112-N) is between 1 and 2 microns.
     
    8. The ion trap (100, 200) of claim 1, wherein at least one of the plurality of capacitors (110-N) is formed to a depth between 250 and 350 microns below a surface of the ion trap (100, 200).
     
    9. The ion trap (100, 200) of claim 1, wherein a trench region of at least one of the plurality of capacitors (110-N) is filled with a polysilicon material.
     
    10. The ion trap (100, 200) of claim 9, wherein the polysilicon material is doped with boron.
     
    11. The ion trap (100, 200) of claim 1, wherein a position of an ion in the ion trap (100, 200) is controlled with a first level of positional control in the first region (114, 214) and a second level of positional control in the second region (116, 216).
     
    12. The ion trap (100, 200) of claim 1, wherein at least one of the plurality of capacitors (110-N) has a capacitance between 90 and 110 picofarads.
     
    13. The ion trap (100, 200) of claim 1, wherein at least one electrode (112-N) is formed out of gold.
     
    14. The ion trap (100, 200) of claim 1, comprising a plurality of vias (109-N) wherein each capacitor (110-N) radially encompasses a respective via (109-N).
     


    Ansprüche

    1. Ionenfalle (100), umfassend:

    eine Vielzahl von Kondensatoren (110-N) in einer ersten Region (114) der Falle, die mit einer ersten Teilung angeordnet sind;

    eine Vielzahl von Elektroden (112-N), die elektrisch an einen jeweiligen Kondensator (110-N) in der ersten Region (114) gekoppelt sind;

    dadurch gekennzeichnet, dass mindestens einige der Elektroden (112-N) in einer zweiten Region (116) der Falle abgeschrägt sind, so dass die Teilung von mindestens einigen der Elektroden (112-N) in der zweiten Region (116) sich von der ersten Teilung unterscheidet.


     
    2. Ionenfalle (100) nach Anspruch 1, wobei die Kondensatoren (110-1, 110-2, 110-N, 210-1, 210-2, 210-N) Grabenkondensatoren sind.
     
    3. Ionenfalle (100) nach Anspruch 1, wobei die erste Teilung (121-N) zwischen 50 Mikrometern und 70 Mikrometern liegt.
     
    4. Ionenfalle (100) nach Anspruch 1, wobei die Teilung zwischen abgeschrägten Elektroden in der zweiten Region (116) der Falle um weniger als 50 Mikrometer variiert.
     
    5. Ionenfalle (100) nach Anspruch 1, wobei die Teilung zwischen abgeschrägten Elektroden in der zweiten Region (116) der Falle auf mehr als 70 Mikrometer zunimmt.
     
    6. Ionenfalle (100, 200) nach Anspruch 1, wobei die abgeschrägten Elektroden (112-N) in der zweiten Region (116) der Falle kontinuierlich abgeschrägt sind.
     
    7. Vorrichtung nach Anspruch 1, wobei die Breite der Elektroden (112-N) zwischen 1 und 2 Mikrometern liegt.
     
    8. Ionenfalle (100, 200) nach Anspruch 1, wobei mindestens einer von der Vielzahl der Kondensatoren (110-N) auf einer Tiefe zwischen 250 und 350 Mikrometern unter einer Oberfläche der Ionenfalle (100, 200) gebildet ist.
     
    9. Ionenfalle (100, 200) nach Anspruch 1, wobei eine Grabenregion von mindestens einem von der Vielzahl der Kondensatoren (110-N) mit einem Polysiliciummaterial gefüllt ist.
     
    10. Ionenfalle (100, 200) nach Anspruch 9, wobei das Polysiliciummaterial mit Bor dotiert ist.
     
    11. Ionenfalle (100, 200) nach Anspruch 1, wobei eine Position eines Ions in der Ionenfalle (100, 200) mit einem ersten Niveau der Positionssteuerung in der ersten Region (114, 214) und einem zweiten Niveau der Positionssteuerung in der zweiten Region (116, 216) gesteuert wird.
     
    12. Ionenfalle (100, 200) nach Anspruch 1, wobei mindestens einer von der Vielzahl der Kondensatoren (110-N) eine Kapazität zwischen 90 und 110 Picofarad aufweist.
     
    13. Ionenfalle (100, 200) nach Anspruch 1, wobei mindestens eine Elektrode (112-N) aus Gold gebildet ist.
     
    14. Ionenfalle (100, 200) nach Anspruch 1, umfassend eine Vielzahl von Durchkontaktierungen (109-N), wobei jeder Kondensator (110-N) eine jeweilige Durchkontaktierung (109-N) radial umschließt.
     


    Revendications

    1. Piège à ions (100) comprenant :

    une pluralité de condensateurs (110-N) dans une première région (114) du piège agencés pour avoir un premier pas ;

    une pluralité d'électrodes (112-N) électriquement couplées à un condensateur respectif (110-N) dans la première région (114),

    caractérisé en ce qu'au moins certaines des électrodes (112-N) sont effilées dans une deuxième région (116) du piège de telle sorte que le pas d'au moins certaines des électrodes (112-N) dans la deuxième région (116) est différent du premier pas.


     
    2. Piège à ions (100) de la revendication 1, dans lequel les condensateurs (110-1, 110-2, 110-N, 210-1, 210-2, 210-N) sont des condensateurs en tranchée.
     
    3. Piège à ions (100) de la revendication 1, dans lequel le premier pas (121-N) fait entre 50 micromètres et 70 micromètres.
     
    4. Piège à ions (100) de la revendication 1, dans lequel le pas entre électrodes effilées dans la deuxième région (116) du piège varie jusqu'à moins de 50 micromètres.
     
    5. Piège à ions (100) de la revendication 1, dans lequel le pas entre électrodes effilées dans la deuxième région (116) du piège augmente jusqu'à plus de 70 micromètres.
     
    6. Piège à ions (100, 200) de la revendication 1, dans lequel les électrodes effilées (112-N) s'effilent de façon continue dans la deuxième région (116) du piège.
     
    7. Appareil de la revendication 1, dans lequel la largeur des électrodes (112-N) se situe entre 1 et 2 micromètres.
     
    8. Piège à ions (100, 200) de la revendication 1, dans lequel au moins un de la pluralité de condensateurs (110-N) est formé jusqu'à une profondeur comprise entre 250 et 350 micromètres au-dessous d'une surface du piège à ions (100, 200).
     
    9. Piège à ions (100, 200) de la revendication 1, dans lequel une région de tranchée d'au moins un de la pluralité de condensateurs (110-N) est remplie avec un matériau à base de silicium polycristallin.
     
    10. Piège à ions (100, 200) de la revendication 9, dans lequel le matériau à base de silicium polycristallin est dopé avec du bore.
     
    11. Piège à ions (100, 200) de la revendication 1, une position d'un ion dans le piège à ions (100, 200) étant contrôlée avec un premier niveau de contrôle de position dans la première région (114, 214) et un deuxième niveau de contrôle de position dans la deuxième région (116, 216).
     
    12. Piège à ions (100, 200) de la revendication 1, dans lequel au moins un de la pluralité de condensateurs (110-N) a une capacité comprise entre 90 et 110 picofarads.
     
    13. Piège à ions (100, 200) de la revendication 1, dans lequel au moins une électrode (112-N) est constituée d'or.
     
    14. Piège à ions (100, 200) de la revendication 1, comprenant une pluralité de trous d'interconnexion (109-N), chaque condensateur (110-N) entourant radialement un trou d'interconnexion respectif (109-N).
     




    Drawing












    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description