WO1997004335A1 - Detecteur de particules sensible a la position et transparent - Google Patents
Detecteur de particules sensible a la position et transparent Download PDFInfo
- Publication number
- WO1997004335A1 WO1997004335A1 PCT/FR1996/001100 FR9601100W WO9704335A1 WO 1997004335 A1 WO1997004335 A1 WO 1997004335A1 FR 9601100 W FR9601100 W FR 9601100W WO 9704335 A1 WO9704335 A1 WO 9704335A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- detector
- detector according
- electron
- impact
- anode
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/244—Detectors; Associated components or circuits therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/28—Measuring radiation intensity with secondary-emission detectors
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
- H01J2237/244—Detection characterized by the detecting means
- H01J2237/24435—Microchannel plates
Definitions
- the present invention relates to a position sensitive particle detector.
- particles is meant in particular the charged particles such as ions and electrons, as well as photons.
- the invention applies in particular to atomic probes and, more generally, to any field in which a correlation between space and time is sought.
- the invention makes it possible to pinpoint precisely, in time and in space, the impacts of particles on a detector provided with means for multiplying electrons (generally wafers of microchannels).
- the invention therefore relates to a two-dimensional space detector with high spatial resolution and high temporal resolution.
- the detectors developed for imaging lead to very good spatial resolution but do not allow the measurement of the instants of impact in a precise manner.
- the first family includes detectors sensitive to simultaneous events but having poor temporal resolution. This is for example the case with CCD camera detectors.
- the second family includes detectors
- resistive anode Resistive Anode Encoder
- wedge and strip anode The best known of these are the resistive anode (“Resistive Anode Encoder”) and the wedge and strip anode.
- detectors are therefore sensitive to only one event at a time. In fact, only two detectors are known capable of pinpointing multiple impacts in time and space.
- the first of these two detectors is known from documents (3) to (7).
- An assembly of microchannel wafers is placed in front of a square network of 10 x 10 anodes, which is arranged in a plane.
- the cloud of electrical charges created by the arrival of an ion impact irradiates a few anodes (an anode having a surface area of the order of 1 cm 2).
- the impact flight time is measured using an electrical signal taken from the rear face of the microchannel wafers.
- This signal also triggers the simultaneous measurement of the 96 charges collected on the anode network.
- the charge collected on each anode is integrated by charge converters whose reading time is too long to allow a rapid reiteration of the measurement. To allow the recording of impacts separated by only 10 ns, several converters are used.
- This first known detector therefore makes it possible to locate both simultaneous impacts and neighboring impacts over time.
- the second known detector is mentioned in document (8).
- microchannel wafers are placed in front of a transparent screen on which a phosphorescent coating is deposited.
- a first light signal is focused, through a lens, on a CCD camera which records the position of the impacts.
- the second light signal is focused on a photomultiplier which measures the time of flight of the impact.
- This photomultiplier includes 80 anodes and therefore allows up to 80 time-of-flight signals to be recorded in parallel. It is then easy to correlate the position of the impacts on this network of anodes with the positions recorded by the CCD camera.
- This second known detector allows simultaneous impacts to be recorded.
- the first detector mentioned above is complex and costly due to the electronic means for load measurement and processing associated with it.
- the second detector mentioned above is complex and expensive because of its constitution.
- the object of the present invention is to remedy the above drawbacks by proposing a spatial particle detector which is sensitive to the position of simultaneous or very close-in impact impacts over time, but which is simpler, more reliable and less costly than the two known detectors. previously mentioned.
- the subject of the present invention is a particle detector, characterized in that it comprises:
- the detector can further comprise photodetection means capable of locating the light pulses emitted by the layer of material.
- These photodetection means can comprise a camera with charge coupling device, more simply called “CCD camera” (for “Charge Coupled Device”), which is intended to receive the light pulses having passed through the electron detection means.
- CCD camera Charge Coupled Device
- the electron multiplication means preferably comprise a plurality of microchannel wafers which are superimposed.
- the electron detection means comprise a set of anode conductors which are transparent to light pulses and electrically isolated from each other.
- the anode conductors can form parallel bands or circular sectors or concentric rings.
- the electron detection means are of analog type.
- these detection means can comprise a wedge and strip anode which is transparent to the light pulses or a resistive anode ("Resistive Anode Encoder”) which is transparent to these light pulses.
- FIG. 1 is a diagrammatic sectional view of a particular embodiment of the device which is the subject of the invention, in which the electron detection means comprise anode conductors in the form of parallel strips,
- FIG. 2 is a schematic top view of these anode conductors
- FIG. 3 to 6 are schematic views of alternative embodiments of the electron detection means.
- the detector according to the invention which is shown diagrammatically in FIGS. 1 and 2, is for example intended to detect ions 2.
- This detector of FIGS. 1 and 2 can for example be integrated into an atomic probe.
- the device of FIGS. 1 and 2 successively comprises:
- the electron multiplication means 4 comprise two microchannel wafers 10 and 12 which are superimposed.
- the microchannels of the wafer 10 form chevrons with the microchannels of the wafer 12.
- three superposed microchannel pancakes could be used, the microchannels of which would no longer form chevrons but Z.
- the electron detection means 8 comprise a set of anode conductors 14 which are transparent to the light capable of being emitted by the layer of light-emitting material 6 and which are electrically isolated from each other.
- the ano, dic conductors 14, or anodes form strips parallel to the surface of a glass plate 15 which is transparent to the light capable of being emitted by the layer 6.
- This layer 6 is a continuous phosphorescent deposit which covers the anodes 14 and is located opposite the microchannel plate 12, the latter itself being arranged below the plate 10.
- Appropriate polarization means 16 are provided for carrying the input face of the wafer 10 at a continuous negative potential equal for example to -5000 V and the output face of the wafer 12 to a continuous negative potential greater than that of the wafer 10 and worth for example -3000 V.
- Layer 6 is referenced to ground.
- Each impact of an ion 2 on the set of microchannel wafers creates a jet of electrons which constitutes a very fine brush 18 containing approximately 10 7 electrons.
- This fineness of the electron spray results from the pinching of the latter at the exit of the pancakes, by the applied electrical voltage.
- the distance between the microchannel plate 12 and the layer of phosphorescent material is very small, for example of the order of 1 to 2 mm.
- Layer 6 is for example made of CaF 2 : Eu and has a thickness sufficiently small to be able to be crossed by the electron brush which has been accelerated by a potential difference of a few kV (3 kV in the example described).
- This layer 6 thus excited emits a light pulse 20 corresponding to the position of the impact of the ion 2 on the wafers of microchannels.
- the light pulse 20 passes through the set of transparent anodes 14 then the glass plate 15.
- each impact is visualized in the form of a very fine light spot.
- the assembly comprising the plate 15, the anodes 14, the layer 6 and the wafers 10 and 12 is mounted on a sealing flange (not shown) because, when the detector is used, the vacuum prevails at - on top of microchannel pancakes (where the ions move) and between them and the phosphorescent layer.
- the device of FIGS. 1 and 2 also comprises photodetection means 22 intended to locate the light pulses emitted by the layer 6.
- These photodetection means include:
- an optical reducer 26 which is interposed between the glass plate 15 and the input face of this camera 24 as seen in FIG. 1, so as to conduct the light leaving the glass plate to this face entry.
- each anode is a thin layer of gold having a thickness of 30 to 50 nm or a thin layer of platinum of the same thickness. It is specified that the number of anodes is a function of the application chosen for the detector.
- the anode network 14 has a triple function in the detector of FIGS. 1 and 2.
- this network of anodes makes it possible to collect and evacuate the brushes of electrons which come from the wafers of microchannels and have passed through the phosphorescent layer 6.
- this network of anodes provides electrical signals allowing the determination of the moments of impact of the particles.
- this network of anodes forms a position-sensitive electron detector.
- this network consists of independent anodes so that the position of the impacts in one of the two perpendicular directions of the plane of the anodes (this plane being the surface 28 of the glass plate carrying these anodes) is known for each. recorded moments.
- these two directions bear the references X and Y respectively, the anodes are parallel to the direction Y and the position of the impacts is known along the direction X.
- the network of anodes is transparent to the light spot produced by layer 6 for each of the impacts.
- the camera 24 makes it possible to locate the light spots emitted by the layer 6 and therefore to determine the position of the impacts since each light pulse is an extension of this impact.
- the detector of FIGS. 1 and 2 makes it possible to correlate each impact position with the moment measured on the corresponding anode which has been irradiated by the electron brush associated with this impact.
- the detector of FIGS. 1 and 2 makes it possible to unambiguously associate an arrival time with each of the light spots produced by the arrival of a burst of ions whose impacts are very close in time or simultaneous.
- the irradiated anode For each of the light spots displayed, the irradiated anode provides a time-of-flight signal.
- the spatial resolution is not given by the width of the anodes but by the resolution of the camera used which digitizes the position of the light spot.
- the number of anodes determines the ability of the detector to associate one and only one flight time with each of the light spots.
- the . ideal operation is obtained when, for each burst of ions (1 to 10 impacts), at most one impact strikes each anode.
- the network of transparent anodes which is covered with a phosphorescent layer, allows, in association with the two microchannel wafers, the spatial localization of the impacts of the ions (thanks to the corresponding light spots) and the measurement of the times which are associated with each of these impacts (thanks to independent anodes).
- this detector Associated with a conventional atomic probe, this detector allows the observation and quantitative analysis of a metallic material on an atomic scale.
- the chemical nature of each of the atoms from which the image is obtained is identified by time of flight mass spectrometry.
- the atomic probe is thus transformed into a three-dimensional atomic probe.
- the detector of FIGS. 1 and 2 has the following advantages compared to the detectors known from documents (3) to (7).
- the detector of FIGS. 1 and 2 is simpler as regards its structure and its implementation: in this detector, the position of an impact is given by a light spot and the measurement of the times of flight is conventional.
- the checkerboard detector known from documents (3) to (7), is of analog type since it is based on the measurement of electrical charges collected by a matrix network of anodes.
- the position coding is binary and considerably reduces the calculation times.
- FIGS. 1 and 2 Compared to the detector known from documents (8) and (9), the detector in FIGS. 1 and 2 is much simpler and has a much greater sensitivity.
- the anodes 14 are connected to means 30 for measuring time respectively by means of electrical conductors 32 which are connected to the ends of these anodes 14.
- the latter include a set of fast time to digital converters 34 which are respectively associated with the anodes.
- the camera 24 is triggered by the "top" of the particles, that is to say the moment when these particles leave their source (not shown).
- this starting signal is an electrical pulse which causes the departure of the ions from the sample to be analyzed and which is used to trigger the opening of the CCD camera.
- Electronic means 31 for processing the signals supplied by the electron detection means 8 and by the photodetection means 22, these means 31 containing the time measurement means 30, are provided for determining the moments and positions of the impacts of the ' particles and correlate these positions with these moments. It is specified that the shape of the anodes is rectangular in the case of FIGS. 1 and 2, which makes it possible to obtain a failure rate independent of the position.
- the anodes 14 constitute a spatial electron detector with which the positions are coded discontinuously.
- FIG. 3 schematically illustrates the possibility of replacing the anodes 14 in the form of parallel strips with anodes which form circular sectors 40 and which are of course still transparent to the light coming from the layer of phosphorescent material (not shown) associated with these anodes.
- FIG. 3 also shows a glass plate 42 on which these anodes 40 are formed and under which the CCD camera is placed (not shown).
- conductors 46 connected to the periphery of the anodes 40 and leading to means (not shown) for processing the signals supplied by these anodes 40.
- FIG. 4 illustrates another possibility of using not anodes in the form of parallel bands but anodes in the form of concentric rings 48 which are still transparent to light coming from the layer of associated phosphorescent material (not shown) and which are still formed on a glass plate 50 below which the CCD camera is placed (not shown).
- These concentric rings are not closed on themselves and we see electrical connectors 52 respectively connected to the ends of these rings and leading to means (not shown) for processing the signals supplied by these rings.
- FIGS. 3 and 4 it is also a discrete coding of the positions of the impacts.
- FIG. 5 schematically illustrates the possibility of using, as an electron detector placed below the layer of phosphorescent material, a wedge and strip anode 54, which is transparent to the light pulses supplied by this layer.
- This anode 54 is produced for example by means of an appropriate deposit of thin gold, on the glass plate 56 below which a CCD camera is still placed for the observation of the light pulses.
- Such an anode is well known in the state of the art and constitutes a set of three electrodes referenced 58, 60 and 62 in FIG. 5.
- the electrode 58 is an array of conductive strips whose width increases linearly in a direction.
- the electrode 60 is a network of triangular electrodes whose area increases linearly in the direction perpendicular to the previous one.
- the electrode 62 "covers" the free surface between the electrodes 58 and 60, these electrodes 58, 60 and 62 being of course electrically isolated from each other.
- the arrival of an ion on the wafers of associated microchannels still produces an electron brush which reaches the anode 54.
- the corresponding charge is then divided between the three electrodes 58, 60 and 62.
- the measurement of the charge collected on each of them makes it possible to calculate the barycenter of the electron brush and to estimate the position of the corresponding impact on the wafers of microchannels.
- the measurement of the three charges is ensured by charge preamplifiers 64, 66 and 68 followed by analog-digital converters 70, 72 and 74, in synchronism with the arrival of the ion.
- the CCD camera makes it possible to determine the positions of the two ions.
- FIG. 6 schematically illustrates the possibility of using, as an electron detector, a resistive anode 76 transparent to the light pulses coming from the layer of associated phosphorescent material (not shown).
- This anode 76 is still formed on a glass plate 78 below which there is a CCD camera (not shown) for the observation of the light pulses from this layer.
- the resistive anode 76 makes it possible to obtain the position of the electron brush which corresponds to the impact of an ion on the wafers of associated microchannels and which arrives on the anode 76.
- the moment of impact information is provided by these pancakes.
- the corners of the anode 76 are respectively connected to charge amplifiers 80, 82, 84 and 86.
- the signals supplied by these amplifiers are processed in means not shown making it possible to obtain the impact position of an electron brush from the microchannel wafers and having passed through the layer of phosphorescent material.
- the invention is not limited to the detection of ion's.
- a detector such as that of FIGS. 1 and 2 also makes it possible to detect the positions of impact of electrons on the wafers of microchannels and the moments of impact of these electrons.
- a planar photocathode (not shown) which is placed above the wafers of microchannels and which provides a brush. of electrons for each photon arriving on this photocathode. This electron brush then arrives on the microchannel wafers and we are brought back to the previous case: we are able to detect the impact position and the moment of impact of the photon on the photocathode.
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Molecular Biology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
- Measurement Of Radiation (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/983,436 US5969361A (en) | 1996-07-16 | 1996-07-16 | Transparent position-sensitive particle detector |
JP9506347A JPH11510246A (ja) | 1995-07-17 | 1996-07-16 | 位置に感じ易い粒子検出器及び透明体 |
EP96924968A EP0839327A1 (fr) | 1995-07-17 | 1996-07-16 | Detecteur de particules sensible a la position et transparent |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR95/08607 | 1995-07-17 | ||
FR9508607A FR2737017B1 (fr) | 1995-07-17 | 1995-07-17 | Detecteur de particules sensible a la position |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997004335A1 true WO1997004335A1 (fr) | 1997-02-06 |
Family
ID=9481037
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR1996/001100 WO1997004335A1 (fr) | 1995-07-17 | 1996-07-16 | Detecteur de particules sensible a la position et transparent |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0839327A1 (fr) |
JP (1) | JPH11510246A (fr) |
FR (1) | FR2737017B1 (fr) |
WO (1) | WO1997004335A1 (fr) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7214947B2 (en) * | 2005-03-25 | 2007-05-08 | General Electric Company | Detector assembly and method of manufacture |
JP6381307B2 (ja) * | 2014-06-11 | 2018-08-29 | キヤノン株式会社 | 放射線画像撮像装置及びその制御方法、並びに、プログラム |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2597254A1 (fr) * | 1986-04-14 | 1987-10-16 | Commissariat Energie Atomique | Dispositif d'imagerie, a grande sensibilite, d'un faisceau de particules |
US5111035A (en) * | 1990-02-22 | 1992-05-05 | Universidad Autonoma Metropolitana | Digital anode to determine the location of electrons on a given surface |
-
1995
- 1995-07-17 FR FR9508607A patent/FR2737017B1/fr not_active Expired - Fee Related
-
1996
- 1996-07-16 WO PCT/FR1996/001100 patent/WO1997004335A1/fr not_active Application Discontinuation
- 1996-07-16 JP JP9506347A patent/JPH11510246A/ja active Pending
- 1996-07-16 EP EP96924968A patent/EP0839327A1/fr not_active Ceased
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2597254A1 (fr) * | 1986-04-14 | 1987-10-16 | Commissariat Energie Atomique | Dispositif d'imagerie, a grande sensibilite, d'un faisceau de particules |
US5111035A (en) * | 1990-02-22 | 1992-05-05 | Universidad Autonoma Metropolitana | Digital anode to determine the location of electrons on a given surface |
Non-Patent Citations (2)
Title |
---|
MARTIN, C ET AL.: "wedge-and strip anodes for centroid- finding position-sensitive photon and particle detectors", REWIEW OF SCIENTIFIC INSTRUMENTS, vol. 52, no. 7, July 1981 (1981-07-01), NEW YORK USA, pages 1067 - 1074, XP002015110 * |
SHULZHENKO,G I ET AL.: "device for recording particle and photon flux distributions", INSTRUMENTS & EXPERIMENTAL TECHNIQUES, vol. 30, no. 3, May 1987 (1987-05-01) - June 1987 (1987-06-01), NEW YORK, USA, pages 685 - 688, XP002015111 * |
Also Published As
Publication number | Publication date |
---|---|
FR2737017B1 (fr) | 1997-08-29 |
FR2737017A1 (fr) | 1997-01-24 |
JPH11510246A (ja) | 1999-09-07 |
EP0839327A1 (fr) | 1998-05-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0810631B1 (fr) | Dispositif d'imagerie radiographique à haute résolution | |
EP0678896B1 (fr) | Dispositif d'imagerie médicale en Rayonnement ionisant X ou gamma à faible dose | |
JP3411580B2 (ja) | 電離放射線検出器 | |
IL114856A (en) | Method and detector for radiation detection in relation to electronic location | |
JP7467621B2 (ja) | 分光技術のための荷電粒子検出 | |
Deconihout et al. | Implementation of an optical TAP: preliminary results | |
FR2951580A1 (fr) | Dispositif d'imagerie radiographique et detecteur pour un dispositif d'imagerie radiographique | |
EP0730291B1 (fr) | Dispositifs d'imagerie médicale en rayonnement ionisant X ou gamma à faible dose | |
JP4570132B2 (ja) | X線画像のサブピクセル分解能のための中心点装置及び方法 | |
EP0002152B1 (fr) | Spectrographe de masse | |
EP0045704B1 (fr) | Détecteur de rayonnement | |
EP0593333B1 (fr) | Cellule de détection, détecteur, capteur et spectroscope | |
EP0320354B1 (fr) | Procédé d'analyse en temps de vol, à balayage continu, et dispositif d'analyse pour la mise en oeuvre de ce procédé | |
FR3070490A1 (fr) | Dispositif et procede d'analyse de matiere par interrogation neutronique | |
EP0839327A1 (fr) | Detecteur de particules sensible a la position et transparent | |
FR2504278A1 (fr) | Detecteur de rayons x | |
Kaya et al. | Characterization and calibration of radiation-damaged double-sided silicon strip detectors | |
FR2827966A1 (fr) | Detecteur de rayonnements ionisants, a lame solide de conversion des rayonnements, et procede de fabrication de ce detecteur | |
Ainbund et al. | Simultaneous spectral and temporal resolution in a single photon counting technique | |
EP3729143B1 (fr) | Procédé d'analyse à l'aide d'un détecteur de particules alpha | |
WO2019063429A1 (fr) | Détecteur de photons à haute énergie | |
FR2570908A1 (fr) | Systeme de traitement des signaux electriques issus d'un detecteur de rayons x | |
Schössler et al. | A reconfigurable Micro-channel plate “RSP” detector for wide-range application in charged particle detection | |
JPH0221284A (ja) | 粒子線検出装置 | |
JPH1039038A (ja) | X線検出装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): JP US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 1996924968 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref country code: JP Ref document number: 1997 506347 Kind code of ref document: A Format of ref document f/p: F |
|
WWE | Wipo information: entry into national phase |
Ref document number: 08983436 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 1996924968 Country of ref document: EP |
|
WWR | Wipo information: refused in national office |
Ref document number: 1996924968 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1996924968 Country of ref document: EP |