EP1052672B1 - Source ionique pour spectromètre de masse à temps de vol analysant des echantillons gazeux - Google Patents

Source ionique pour spectromètre de masse à temps de vol analysant des echantillons gazeux Download PDF

Info

Publication number
EP1052672B1
EP1052672B1 EP00401028A EP00401028A EP1052672B1 EP 1052672 B1 EP1052672 B1 EP 1052672B1 EP 00401028 A EP00401028 A EP 00401028A EP 00401028 A EP00401028 A EP 00401028A EP 1052672 B1 EP1052672 B1 EP 1052672B1
Authority
EP
European Patent Office
Prior art keywords
electrons
ion source
flow
electron beam
electrode
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
EP00401028A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP1052672A1 (fr
Inventor
Didier Pierrejean
Bruno Galland
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alcatel CIT SA
Alcatel Lucent SAS
Original Assignee
Alcatel CIT SA
Alcatel SA
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 Alcatel CIT SA, Alcatel SA filed Critical Alcatel CIT SA
Publication of EP1052672A1 publication Critical patent/EP1052672A1/fr
Application granted granted Critical
Publication of EP1052672B1 publication Critical patent/EP1052672B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/10—Ion sources; Ion guns
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J27/00—Ion beam tubes
    • H01J27/02—Ion sources; Ion guns
    • H01J27/04—Ion sources; Ion guns using reflex discharge, e.g. Penning ion sources
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/08—Electron sources, e.g. for generating photo-electrons, secondary electrons or Auger electrons
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/02—Details
    • H01J49/10—Ion sources; Ion guns
    • H01J49/14—Ion sources; Ion guns using particle bombardment, e.g. ionisation chambers
    • H01J49/147—Ion sources; Ion guns using particle bombardment, e.g. ionisation chambers with electrons, e.g. electron impact ionisation, electron attachment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/04—Electron multipliers
    • H01J43/06—Electrode arrangements
    • H01J43/18—Electrode arrangements using essentially more than one dynode
    • H01J43/24—Dynodes having potential gradient along their surfaces
    • H01J43/246—Microchannel plates [MCP]

Definitions

  • the present invention relates to ionization means of gaseous samples for analysis in a mass spectrometer.
  • a sample is analyzed gaseous by bombarding the sample with a stream of electrons, then moving the ions thus obtained to differentiate them then according to their trajectory or their speed.
  • the ions produced by the ion source are launched at the entrance to a tube of flight in which they maintain a constant speed, and detects at the exit of the flight tube the flight time corresponding to each type of ions in the gaseous sample to be analyzed, to deduce their nature. It is necessary for that to launch at the entrance of the flight tube a previously accelerated ion packet, identify the departure time of the packet of ions, and identify the arrival times of the different ions at the other end of the flight tube.
  • Ionic sources commonly used in mass spectrometers include an electron gun having a source of electrons and one or more electrodes of conditioning the electron flow to generate a flow of suitable electrons directed to a gas ionization zone in which ions are formed which are subjected to one or more electrodes ion flow conditioning.
  • the flow of electrons is usually directed to the gas ionization zone in a direction perpendicular to the direction of the flight tube of the mass spectrometer. This results in significant bulk, and a difficulty of integration. The quantity of ions produced is relatively low, which limits the sensitivity of the device.
  • the problem proposed by the present invention is design a new ion source structure for mass spectrometer, having a greater compactness and a greater sensitivity, being easily integrated with other components of a mass spectrometer.
  • a source ionic system for a mass spectrometer comprises a electron gun having an electron source and one or more electrons flow conditioning electrodes to generate a appropriate electron flow directed to a gas ionization zone in which ions are formed which are subject to one or more ion flow conditioning electrodes; downstream Electron flow conditioning electrodes, interposed in the electron stream one or more microchannel pancakes, so that from a pulsed primary electron beam relatively few electrons, a beam is generated secondary electronic pulsed containing a lot of electrons.
  • microchannel pancakes ensure a multiplication of flow of electrons, so the subsequent ionization of the gaseous sample is also multiplied. Sensitivity and resolving power of the device are thus greatly increased.
  • At least one additional electrode adapted to disperse the beam secondary electronics in order to preserve its qualities while improving its spatial qualities.
  • the increase of the ionization is still favored of the gaseous sample, and therefore the sensitivity of a device incorporating the ion source.
  • the gas ionization zone is located between an upstream repulsion electrode traversed by the beam secondary electronics and retaining the electrons by pushing back the ions, and a downstream acceleration electrode that attracts the ions.
  • the ionization zone should preferably be close immediate or microchannel slabs, so that the beam secondary electronics retains its temporal qualities and remains dense, so that all the ions in a packet of ions penetrate substantially at the same time in the flight tube.
  • the primary electron beam is then pulse modulated by a deflection electrode.
  • the electron source can advantageously to be a microtip field emission cathode, producing a pulse-modulated primary electron beam.
  • the invention can find particular application in the production of time-of-flight spectrometers incorporating such ion source.
  • a mass spectrometer to flight time comprises of generally an electron gun 1, followed by an ion gun 2, itself followed by a flight tube 3 whose output communicates with a ion detector 4.
  • the electron gun 1 comprises an electron source 5.
  • the electron source 5 is a filament such as a tungsten filament fed by a heating generator 6 to be heated to a temperature sufficient to provide ion thermoemission.
  • Electrons emitted by the electron source 5 are solicited by one or more electron flow conditioning electrodes 7, for example an acceleration electrode 71 and one or more electrodes of focus 72.
  • a deflection electrode 73 makes it possible to pulse modulating the outgoing electron flow 8.
  • a microtip field emission cathode comprising a conductive substrate on which microtips are made conductors engaged in cavities of an insulating layer interposed between the substrate and a positively polarized gate.
  • Such a microtip field emission cathode makes it possible to modulate by itself the outgoing flow of electrons, without requiring of deflection electrode 73.
  • microchannel slab 9 and 10 Downstream of the flow conditioning electrodes of electrons 7, one interposes according to the invention in the flow of electrons 8 one or more microchannel patties.
  • a first microchannel slab 9 and a second microchannel slab 10 separated from each other by an intergalette electrode 11.
  • a from an 8-pulsed primary electronic beam containing relatively few electrons, microchannel slabs 9 and 10 generate a pulsed secondary electron beam containing many electrons, giving a gain of 100 to several thousands.
  • the primary electron beam can be equivalent to an electric current of the order of 1 to 10 ⁇ A, and the secondary electron beam can correspond to several milliamps, according to the gain of the microchannel slabs 9 and 10.
  • Primary 8 and Secondary 12 electron beams can for example be formed of pulses whose duration is the order of the nanosecond.
  • a microchannel slab 9 is a generally flat element having a thickness E of the order of 0.5 mm, and consisting of side-by-side juxtaposition a very large number of very small glass capillary tubes diameter, comprising for example the tube 13, oriented according to axes perpendicular to the general plane of the slab 9.
  • the tubes capillaries may have a diameter e of about 12 microns, and they are open at both ends on the faces
  • the main faces of the slab 9 are metallized, to constitute, as illustrated in FIG. an input electrode 14 and an output electrode 15, subjected to a potential difference VD.
  • the potential of the electrode output 15 is greater than the potential of the input electrode 14.
  • the inner wall of the capillary tube 13 is treated to present a suitable resistance, and forms an electron multiplier independent secondary.
  • an electron beam primary electronics 8 gets into tube 13 it can come hit the wall of the tube 13 and pick up one or more others electrons that are accelerated by the present electric field between the input electrodes 14 and output 15.
  • the electrons thus detached will strike themselves the opposite wall of the tube 13, picking up other electrons that are themselves accelerated, and he results from step by step the multiplication of electrons in movement, producing a secondary electron beam 12 containing a lot of electrons.
  • the beam secondary electronics 12 propagates to an ionization zone 16 inside the ion gun 2.
  • the electrons hit the atoms of the gaseous sample at analyze, and transform them into ions.
  • the gas ionization zone 16 is located between a repulsive electrode 17 upstream traversed by the secondary electron beam 12 and which retains the electrons by repelling ions, and an accelerating electrode downstream 18 which attracts the ions.
  • the ion stream 19 thus produced is sent to the inlet 20 of the flight tube 3, then travels the length of the flight tube 3 to exit through its exit 21 and enter the ion detector 4.
  • the ion source is arranged in line at the entrance of flight tube 3 of the spectrometer of mass in flight time.
  • the ion detector 4 may comprise wafers to microchannels 22 and 23, generating a multiplied electron flow from strike a target electrode 24. The measurement is made by detecting the electrical pulses collected by the target electrode 24.
  • the ionization zone 16 is close immediate microchannel slab 10, of which it is separated by a reduced distance, for example from 1 to 2 mm approximately.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Combustion & Propulsion (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Electron Tubes For Measurement (AREA)
  • Electron Sources, Ion Sources (AREA)
EP00401028A 1999-04-22 2000-04-13 Source ionique pour spectromètre de masse à temps de vol analysant des echantillons gazeux Expired - Lifetime EP1052672B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9905088A FR2792773B1 (fr) 1999-04-22 1999-04-22 Source ionique pour spectrometre de masse a temps de vol analysant des echantillons gazeux
FR9905088 1999-04-22

Publications (2)

Publication Number Publication Date
EP1052672A1 EP1052672A1 (fr) 2000-11-15
EP1052672B1 true EP1052672B1 (fr) 2004-10-13

Family

ID=9544732

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00401028A Expired - Lifetime EP1052672B1 (fr) 1999-04-22 2000-04-13 Source ionique pour spectromètre de masse à temps de vol analysant des echantillons gazeux

Country Status (6)

Country Link
US (1) US6545269B1 (ja)
EP (1) EP1052672B1 (ja)
JP (1) JP4395584B2 (ja)
AT (1) ATE279783T1 (ja)
DE (1) DE60014758T2 (ja)
FR (1) FR2792773B1 (ja)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6806467B1 (en) * 2003-07-24 2004-10-19 The Regents Of The University Of California Continuous time-of-flight ion mass spectrometer
US7420472B2 (en) * 2005-10-16 2008-09-02 Bao Tran Patient monitoring apparatus
US8575542B1 (en) * 2012-04-18 2013-11-05 Bruker Daltonics, Inc. Method and device for gas-phase ion fragmentation
WO2014003937A1 (en) * 2012-06-29 2014-01-03 Fei Company Multi Species Ion Source
KR101786950B1 (ko) 2014-12-30 2017-10-19 한국기초과학지원연구원 비행시간 질량분석기
US9899181B1 (en) 2017-01-12 2018-02-20 Fei Company Collision ionization ion source
US9941094B1 (en) 2017-02-01 2018-04-10 Fei Company Innovative source assembly for ion beam production
CN109461642B (zh) * 2018-12-07 2024-04-02 中国烟草总公司郑州烟草研究院 一种离子引发电子轰击电离源
US11854777B2 (en) * 2019-07-29 2023-12-26 Thermo Finnigan Llc Ion-to-electron conversion dynode for ion imaging applications

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3852595A (en) * 1972-09-21 1974-12-03 Stanford Research Inst Multipoint field ionization source
US3819941A (en) * 1973-10-15 1974-06-25 Bendix Corp Mass dependent ion microscope having an array of small mass filters
FR2294539A1 (fr) * 1974-12-13 1976-07-09 Labo Electronique Physique Dispositif ioniseur incluant une galette de microcanaux a emission electronique secondaire
US5659170A (en) * 1994-12-16 1997-08-19 The Texas A&M University System Ion source for compact mass spectrometer and method of mass analyzing a sample
JP3778664B2 (ja) * 1997-07-24 2006-05-24 浜松ホトニクス株式会社 マイクロチャネルプレートを用いたイオン源

Also Published As

Publication number Publication date
ATE279783T1 (de) 2004-10-15
US20030057378A1 (en) 2003-03-27
US6545269B1 (en) 2003-04-08
DE60014758D1 (de) 2004-11-18
FR2792773A1 (fr) 2000-10-27
JP4395584B2 (ja) 2010-01-13
FR2792773B1 (fr) 2001-07-27
JP2000348665A (ja) 2000-12-15
EP1052672A1 (fr) 2000-11-15
DE60014758T2 (de) 2006-03-09

Similar Documents

Publication Publication Date Title
EP1676291B1 (en) Ion mobility tof/maldi/ms using drift cell alternating high and low electric field regions
JP3801866B2 (ja) 飛行時間型質量分析計
US6323482B1 (en) Ion mobility and mass spectrometer
US7385185B2 (en) Molecular activation for tandem mass spectroscopy
US8101923B2 (en) System and method for spatially-resolved chemical analysis using microplasma desorption and ionization of a sample
US8648295B2 (en) Combined distance-of-flight and time-of-flight mass spectrometer
EP1994545B1 (en) Mass spectrometer for trace gas leak detection with suppression of undesired ions
EP1052672B1 (fr) Source ionique pour spectromètre de masse à temps de vol analysant des echantillons gazeux
FR2461351A1 (fr) Source d'ions a plasma uhf
US7838820B2 (en) Controlled kinetic energy ion source for miniature ion trap and related spectroscopy system and method
US20050023459A1 (en) Time of flight mass spectrometry apparatus
JP5504969B2 (ja) 質量分析装置
US7112787B2 (en) Ion trap mass spectrometer and method for analyzing ions
US6469296B1 (en) Ion acceleration apparatus and method
JPH07307140A (ja) 質量分析装置及びイオン源
JPH11288683A (ja) 大気圧イオン化質量分析計
EP0362953A1 (fr) Tube neutronique scellé muni d'une source d'ions à confinement électrostatique des électrons
JP2000011947A (ja) 飛行時間型質量分析装置
Setz et al. Design and performance of an atmospheric pressure sampling interface for ion-trap/time-of-flight mass spectrometry
JP2002532845A (ja) 衝突誘導解離を使用する分子構造分析用のインライン反射飛翔時間型質量分析計
Just et al. Selective elimination of low‐molecular‐weight ions in MALDI‐TOF mass spectrometry using a bipolar pulsed electrostatic particle guide
FR2645676A1 (fr) Cathode possedant une surface d'emission secondaire amelioree et amplificateur a champ croise contenant une telle cathode
JP2008084850A (ja) イオントラップ飛行時間型質量分析装置
Hang et al. Evaluation of ion transport processes in a heated capillary tube interface for electrospray ionization time-of-flight mass spectrometryPresented at the 2001 European Winter Conference on Plasma Spectrochemistry, Lillehammer, Norway, February 4–8, 2001. Invited Lecture
FR2599891A1 (fr) Spectrometre de masse, notamment, pour detecteur de fuites, sous vide pousse

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20010515

AKX Designation fees paid

Free format text: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20041013

Ref country code: IE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20041013

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20041013

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20041013

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: FRENCH

REF Corresponds to:

Ref document number: 60014758

Country of ref document: DE

Date of ref document: 20041118

Kind code of ref document: P

REG Reference to a national code

Ref country code: CH

Ref legal event code: NV

Representative=s name: CABINET ROLAND NITHARDT CONSEILS EN PROPRIETE INDU

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050113

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050113

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050113

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050124

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20041230

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050413

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050430

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050430

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050714

BERE Be: lapsed

Owner name: ALCATEL

Effective date: 20050430

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20060411

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20060418

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20060419

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20060420

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20060430

Year of fee payment: 7

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20070413

BERE Be: lapsed

Owner name: *ALCATEL

Effective date: 20050430

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050313

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20071101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070430

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070430

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070413

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070430

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070413