WO2009027252A2 - Dispositif de mesure d'un flux de particules - Google Patents

Dispositif de mesure d'un flux de particules Download PDF

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Publication number
WO2009027252A2
WO2009027252A2 PCT/EP2008/060773 EP2008060773W WO2009027252A2 WO 2009027252 A2 WO2009027252 A2 WO 2009027252A2 EP 2008060773 W EP2008060773 W EP 2008060773W WO 2009027252 A2 WO2009027252 A2 WO 2009027252A2
Authority
WO
WIPO (PCT)
Prior art keywords
measuring
divider
mass spectrometer
current
particle
Prior art date
Application number
PCT/EP2008/060773
Other languages
German (de)
English (en)
Other versions
WO2009027252A3 (fr
Inventor
Norbert Rolff
Original Assignee
Inficon Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Inficon Gmbh filed Critical Inficon Gmbh
Publication of WO2009027252A2 publication Critical patent/WO2009027252A2/fr
Publication of WO2009027252A3 publication Critical patent/WO2009027252A3/fr

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/025—Detectors specially adapted to particle spectrometers

Definitions

  • the invention relates to a device for measuring a particle flow of charged particles, in particular in a mass spectrometer for the analysis of gases.
  • ions are accelerated and exposed to the action of a deflection device.
  • different distractions occur.
  • particles of different mass contained in a gas stream can be selectively extracted.
  • the electrically charged particles hit a collector to which they release their charge, generating a current in a circuit connected to the collector.
  • the through each particle caused electricity is very small. For example, an ion a charge of 1.6 ⁇ 10 ⁇ i9 A s.
  • the smaller the measurable current the faster the particle current can be determined for a certain mass and then transferred to the measurement of the next mass. Therefore, the measuring range should include the smallest possible carrier densities.
  • the Hess Kunststoff GmbH should also make it possible to quantitatively determine and display large amounts of gas. This requires a very high current measuring range over many powers of ten for a sufficiently fast operation of the analyzer.
  • An ion-detection arrangement for a time-of-flight mass spectrometer comprises an ion beam splitter which intercepts a first portion of the incident ion quantity which has passed through the time-of-flight mass spectrometer while a second portion of the ion quantity passes through the ion beam splitter.
  • Each of the two ion beams is detected in an electron multiplier which generates a signal representing the respective ion quantity.
  • a device is used to measure an amount of charge flowing in a vacuum, wherein the charged particles strike a first collector, which traps a subset of the charge carriers and transmits another subset.
  • a second catcher and then a third catcher is arranged in the particle stream behind the first catcher.
  • a third catcher is arranged at each catcher a portion of the Te ⁇ lchenstroms is intercepted and the resulting current is fed to a current measuring unit.
  • the current measuring units are electrical amplifiers, each designed for different measuring ranges and their output signals are combined. Due to the limited amplification of the individual amplifiers, the measuring range is limited. It is also known to assign individual samplers current measuring units with different measuring ranges. A sufficiently large total measuring range is not achieved.
  • the invention has for its object to provide an apparatus for measuring a particle flow of charged particles, which provides for each of the different particle masses short Answerze ⁇ ten and gas leakage rates can be determined in a wide range.
  • the device according to the present invention is characterized by claim 1. It has a divider that lets through a first portion of particles and captures a second portion. A first Hess issued serves to measure the first portion of the particle flow and a second measuring device is used to measure the second portion of the particle flow.
  • the invention provides that the first measuring device includes a secondary electron multiplier and a Stromauswakened issued, while the second measuring device performs an analog current measurement.
  • the first measuring device forms a fine measuring branch capable of measuring very small ion currents, down to individual ions which produce individual pulses in the photomultiplier which can be counted.
  • the second measuring device forms a coarse measuring branch for measuring large ion currents, in which the individual ions at the expensive produce a continuous current, which is amplified by an analogue amplifier. In this way, an extremely large combined Meßbere ⁇ ch realize.
  • the secondary electron multiplier is directly or indirectly acted upon by particles passing through the divider. Those particles that are trapped by the splitter cause the generation of a charge current that can be amplified by an electrical analog amplifier for subsequent measurement. These are large measured values, as they occur, for example, with large gas quantities.
  • the portion of the particle flow that passes through the divider serves to drive the secondary electron multiplier.
  • a secondary electron multiplier has the advantage of an extremely high amplification factor in the order of 10 s to 10 7 .
  • the second part of the particle flow which passes through the divider thus serves to determine the smallest charge quantities.
  • the coarse measuring branch contains an analog electrical amplifier, while the fine measuring branch contains a very high amplification secondary electron multiplier and a current evaluation device.
  • the invention enables short measurement times (fast response) in the case of small particle flow dikes. For longer integration times, currents down to about 1 particle (ion) per second can be measured.
  • the current evaluation device can consist of an amplifier and a pulse counter and / or the output currents of the secondary electron multiplier can also be measured as current with an electrical analog amplifier.
  • a scintillator is arranged in the particle path behind the divider, which emits photons in accordance with the impact of particles, and the photomultiplier is a photomultiplier.
  • the photomultiplier is a photomultiplier.
  • the particles to be measured are either ions or electrons.
  • the divider is preferably designed such that the transmitted first portion is substantially larger than the collected second portion of the particle stream. In this way, the photomultiplier is driven by a relatively large proportion of the amount of particles, so that the sensitivity is increased.
  • the coarse measuring branch is charged with a smaller proportion of the amount of particles.
  • a possible metering ratio for the divider is 9: 1, with 90% of the particulate amount passing through, while 10% is trapped and fed to the coarse gauge.
  • the Feinmesszweig receives a large proportion of the available amount of particles and the coarse measuring branch receives a small proportion.
  • the Feinmesszweig contains a pulse counter and / or another analog amplifier which receives the output current of the photomultiplier, this relatively large current is easy and quick to detect, while the coarse measuring branch performs a direct measurement of the Teuchenstroms and converts the measured variable into an electrical signal.
  • the device according to the invention is particularly suitable for mass spectrometers and for leak detectors containing mass spectrometers.
  • the mass spectrometer can be a controlled deflection device for diversion have different masses.
  • it may be a quadrupole mass spectrometer or a sector field mass spectrometer.
  • Fig. 1 is a schematic representation of a preferred embodiment
  • Fig. 2 shows an embodiment in which the
  • Secondary electron multiplier is a directly coupled to a mass spectrometer electron multiplier.
  • a mass spectrometer 10 which has a housing 11 sealed in a vacuum-tight manner.
  • the mass spectrometer contains in a vacuum space 12 a deflection device 13, which is, for example, a quadrupole deflection device.
  • This has four rod-shaped electrodes, which cause a deflection of a gas ion current according to their charge, with a division according to ion masses.
  • the particle flow leaving the deflection device 13 in the direction of the target is to be determined in order to obtain a quantitative statement of the mass flow of a particular mass.
  • a divider 14 is arranged behind the deflection device 13. This selects a certain proportion of the particle flow for the passage, while the remaining portion intercepted used to generate a current.
  • the divider 14 includes, for example, parallel wires or strips 15 of conductive material connected to a drain 16. The gaps between the strips 15 are part of the particle flow happens. In the present example, the area rate of the strips 15 at the area of the divider 14 is 10%, while the gaps are 90%.
  • the divider 14 divides the particle flow into two partial streams. The one partial flow is measured in a coarse measuring branch 17 and the other in a fine measuring branch 18.
  • the coarse measuring branch 17 contains a connected to the derivative 16 analog electrical amplifier 19 and an AD Wandier 20. The discharged from the particles to the divider 14 charges generated in the derivative 16 a current whose strength determines the output signal of the AD converter 20.
  • a scintillator 21 is arranged in the vacuum space 12, which receives incident electrically charged particles and emits photons according to the recorded charge.
  • the scintillator can consist of a phosphor screen, which is located at a current-limited high voltage.
  • the light of the emitted photons passes through a translucent window 22 of the housing 11 and falls onto a photomultiplier 25, which is arranged outside the housing 11 and has its own vacuum housing 26.
  • the photomultiplier 25 is here a photomultiplier, which converts light into electrical signals and has an extremely high sensitivity.
  • the amplification factor is usually 10 5 to 10 7 .
  • the secondary electron multiplier contains cascaded staggered dynodes 27, from which incident electrons trigger secondary electrons.
  • the photocathode of a photomultiplier responds to light, while the subsequent dynodes react to electrons.
  • the photomultiplier 25 is powered by a utility power supply, preferably via current limiting, to protect it from high currents.
  • the output 28 of the photomultiplier is connected to an electrical amplifier 29 whose Jardinsigna! a pulse counter 30 is supplied. Parallel to the pulse counter 30 is also an analog detection of the output signal of the photomultiplier present. With ion currents in the upper range, which by the
  • the pulse counter 30 provides a counter frequency and the second analog amplifier 32 carries an output voltage which is proportional to the divider current transmitted by the divider 14.
  • the signals of the pulse counter 30 and the A / D converter 33 are supplied to an evaluation device 31.
  • the amplifier 29 with the pulse counter 30 and the amplifier 32 with the A / D converter constitute the current evaluating means 34.
  • the pulse counter 30 counts the number of particles each causing a pulse at the smallest particle density, that is, at the most sensitive measuring range. For larger particles, a quasi-continuous current is produced at the output of the secondary electron multiplier. This is amplified by the amplifier 32 and supplied to the evaluation device 31 after digitization by the A / D converter 33. On the basis of the measured current value, the evaluation device 31 switches on either the Hess path 29, 30 or the measuring path 32, 33.
  • the evaluation device 31 also effects a switching between the fine measuring branch 18 and the coarse measuring branch 17 as a function of the measured current.
  • the output signals of coarse measuring branch 17 and fine measuring branch 18 are fed to the evaluation device 31, for example a computer.
  • a different combination of the two measured values can be made or even a selection.
  • the evaluation device can tune the amplification of the evaluation branches in the event that the particle flow falls within the correct range. This makes it possible, for. B. to calibrate only the Grobmesszweig manually and let the other branches automatically calibrate.
  • the use of the scintillator 21 has the advantage that the photomultiplier 25 contains its own vacuum, which is independent of the vacuum of the housing 11. This prevents air intrusions into the housing 11 from destroying the secondary electron multiplier.
  • an electrical separation of the amplifier of the coarse measuring branch 17 and the Feinmesszwe ⁇ ges 18 is mögiich.
  • the electrical supplies of the amplifier of both branches can be set to the same ground potential, whereby the circuit complexity is reduced.
  • the coarse measuring branch and the fine measuring branch cover a very large ion current range.
  • a fast response is desired.
  • An ion has a charge of 1.6 E-19 As.
  • the upper limit of the fine measuring branch is 100 MHz. This corresponds to a number of 1,000,000 pulses / 10 ms or a current of 1.6 E-Il A.
  • the measuring range of the coarse measuring branch 17 is 1.6 E-13 to 1 E -4A. Since, however, only 10% of the particle quantity accounts for the coarse measuring branch, the particle flow is 1.6 E-12.
  • the exemplary embodiment of FIG. 2 differs from that of FIG. 1 only in that the secondary electron multiplier 25a is connected directly to the housing 11, so that the particle current passing through the splitter 14 directly strikes the input stage of the secondary electron multiplier 25a.
  • the window 22 in this case is an opening through which the particles can pass.
  • the vacuum housing 26 receives its vacuum from the housing 11. In this variant, a scintillator is not required.
  • the secondary electron multiplier is an ion multiplier.

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  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Measurement Of Radiation (AREA)
  • Electron Tubes For Measurement (AREA)

Abstract

Le flux de particules chargées électriquement, généré dans un spectromètre de masse (10), est acheminé vers un séparateur (14) qui laisse passer une fraction du flux de particules et piège une autre fraction. La première fraction est acheminée, directement ou par l'intermédiaire d'un scintillateur (21), vers un photomultiplicateur (25) présentant un gain extrêmement élevé. Les impulsions générées par les particules incidentes (ions) sont dénombrées par un compteur d'impulsions (30) ou reçues et transformées au moyen d'un amplificateur analogique (32). Une branche de mesure approximative (17) amplifie le courant électrique sortant du séparateur (14). Les deux branches de mesure sont réunies dans un dispositif d'évaluation (31). Le dispositif de mesure possède un temps de réponse court et une très grande plage de mesure.
PCT/EP2008/060773 2007-08-30 2008-08-15 Dispositif de mesure d'un flux de particules WO2009027252A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007040921.6 2007-08-30
DE102007040921A DE102007040921A1 (de) 2007-08-30 2007-08-30 Vorrichtung zur Messung eines Teilchenstroms

Publications (2)

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WO2009027252A2 true WO2009027252A2 (fr) 2009-03-05
WO2009027252A3 WO2009027252A3 (fr) 2009-10-15

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011048060A2 (fr) 2009-10-23 2011-04-28 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
WO2011048061A2 (fr) 2009-10-23 2011-04-28 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
GB2486484A (en) * 2010-12-17 2012-06-20 Thermo Fisher Scient Bremen A detection system for a time-of-flight mass spectrometer
WO2012080443A1 (fr) * 2010-12-17 2012-06-21 Thermo Fisher Scientific (Bremen) Gmbh Système d'acquisition de données et procédé de spectrométrie de masse
CN104749415A (zh) * 2015-03-09 2015-07-01 中国船舶重工集团公司第七一九研究所 一种基于电子倍增器的探测器

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020175292A1 (en) * 2001-05-25 2002-11-28 Whitehouse Craig M. Multiple detection systems
WO2002097856A2 (fr) * 2001-05-29 2002-12-05 Thermo Finnigan Llc Spectrometre de masse a temps de vol et capteur multiple associe
US20070018113A1 (en) * 2001-12-19 2007-01-25 Ionwerks, Inc. Multi-anode detector with increased dynamic range for time-of-flight mass spectrometers with counting data acquisitions

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5026988A (en) * 1989-09-19 1991-06-25 Vanderbilt University Method and apparatus for time of flight medium energy particle scattering
DE4019005C2 (de) * 1990-06-13 2000-03-09 Finnigan Mat Gmbh Vorrichtungen zur Analyse von Ionen hoher Masse
DE19502439B4 (de) 1994-02-11 2007-08-16 Oc Oerlikon Balzers Ag Verfahren und Messanordnung zum Messen der pro Zeiteinheit einen Vakuumvolumenbereich in gegebener Richtung durchströmenden elektrischen Ladungsmenge und deren Verwendung für Massenspektrometer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020175292A1 (en) * 2001-05-25 2002-11-28 Whitehouse Craig M. Multiple detection systems
WO2002097856A2 (fr) * 2001-05-29 2002-12-05 Thermo Finnigan Llc Spectrometre de masse a temps de vol et capteur multiple associe
US20070018113A1 (en) * 2001-12-19 2007-01-25 Ionwerks, Inc. Multi-anode detector with increased dynamic range for time-of-flight mass spectrometers with counting data acquisitions

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KRISTO M J ET AL: "SYSTEM FOR SIMULTANEOUS COUNT/CURRENT MEASUREMENT WITH A DUAL-MODE PHOTON/PARTICLE DETECTOR" REVIEW OF SCIENTIFIC INSTRUMENTS, AIP, MELVILLE, NY, US, Bd. 59, Nr. 3, 1. März 1988 (1988-03-01), Seiten 438-442, XP000103497 ISSN: 0034-6748 *

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013508905A (ja) * 2009-10-23 2013-03-07 サーモ フィッシャー サイエンティフィック （ブレーメン） ゲーエムベーハー 荷電粒子を検出する検出装置、荷電粒子を検出する方法および質量分析計
WO2011048061A2 (fr) 2009-10-23 2011-04-28 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
WO2011048060A3 (fr) * 2009-10-23 2011-06-16 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
WO2011048061A3 (fr) * 2009-10-23 2011-06-16 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
US8680481B2 (en) 2009-10-23 2014-03-25 Thermo Fisher Scientific (Bremen) Gmbh Detection apparatus for detecting charged particles, methods for detecting charged particles and mass spectrometer
WO2011048060A2 (fr) 2009-10-23 2011-04-28 Thermo Fisher Scientific (Bremen) Gmbh Appareil et procédés de détection de particules chargées, et spectromètre de masse
US8642973B2 (en) 2009-10-23 2014-02-04 Thermo Fisher Scientific (Bremen) Gmbh Detection apparatus for detecting charged particles, methods for detecting charged particles and mass spectrometer
CN102782800A (zh) * 2009-10-23 2012-11-14 塞莫费雪科学（不来梅）有限公司 检测带电粒子的检测装置、检测带电粒子的方法以及质谱仪
JP2013508904A (ja) * 2009-10-23 2013-03-07 サーモ フィッシャー サイエンティフィック （ブレーメン） ゲーエムベーハー 荷電粒子を検出する検出装置、荷電粒子を検出する方法および質量分析計
WO2012080268A1 (fr) * 2010-12-17 2012-06-21 Thermo Fisher Scientific (Bremen) Gmbh Système et procédé de détection d'ions
GB2486484B (en) * 2010-12-17 2013-02-20 Thermo Fisher Scient Bremen Ion detection system and method
GB2498505A (en) * 2010-12-17 2013-07-17 Thermo Fisher Scient Bremen Data acquisition system and method for mass spectrometry
US20130264474A1 (en) * 2010-12-17 2013-10-10 Alexander Kholomeev Ion Detection System and Method
WO2012080443A1 (fr) * 2010-12-17 2012-06-21 Thermo Fisher Scientific (Bremen) Gmbh Système d'acquisition de données et procédé de spectrométrie de masse
GB2486484A (en) * 2010-12-17 2012-06-20 Thermo Fisher Scient Bremen A detection system for a time-of-flight mass spectrometer
US9214322B2 (en) 2010-12-17 2015-12-15 Thermo Fisher Scientific (Bremen) Gmbh Ion detection system and method
GB2498505B (en) * 2010-12-17 2016-07-13 Thermo Fisher Scient (Bremen) Gmbh Data acquisition system and method for mass spectrometry
US9530632B2 (en) 2010-12-17 2016-12-27 Thermo Fisher Scientific (Bremen) Gmbh Ion detection system and method
US10074528B2 (en) 2010-12-17 2018-09-11 Thermo Fisher Scientific (Bremen) Gmbh Data acquisition system and method for mass spectrometry
CN104749415A (zh) * 2015-03-09 2015-07-01 中国船舶重工集团公司第七一九研究所 一种基于电子倍增器的探测器

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WO2009027252A3 (fr) 2009-10-15
DE102007040921A1 (de) 2009-03-05

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