Development of a Low Cost, Low Power, Miniature Sector Mass Spectrometer with IonCCD Detection

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1 Leidos Proprietary Development of a Low Cost, Low Power, Miniature Sector Mass Spectrometer with IonCCD Detection Leidos; MIT MTL; Northeastern University; OI Analytical

2 Development Team Noah Christian, Leidos, Inc. Deborah Hunka, Leidos, Inc. James Ha, Leidos, Inc. Tim McPhail, Leidos, Inc. Meredith Melendez, Leidos, Inc. Jean Sebastien Pradel, Leidos, Inc. Augie Ifarraguerri, Leidos, Inc. Dave Nichols, Leidos, Inc. Gottfried Kibelka, CMS Field Products Carol Livermore, Northeastern University Luis Fernando Velásquez García, Massachusetts Institute of Technology Chenye Yang, Massachusetts Institute of Technology 2 Funding by Leidos and Intelligence Advanced Research Projects Activity, Kristy DeWitt Program Manager The research is based upon work supported by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), via Air Force Research Laboratories contract FA C 9103, and work supported by Leidos Exploratory Research and Development Funding. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the ODNI, IARPA, or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright annotation thereon.

3 Program Goals Derive a new architecture for mass spectrometry that focuses on: Power efficiency Size Weight Ruggedness Simple and low cost Extend established mass spectrometry identification approaches to a small mass spectrometer Using Electron Impact Ionization Maximize library size Maximize identification Create an extensible and modular system for chemical identification 3

4 Mass Spectrometer Block Diagram Sample Inlet Ionization Source Ion Transfer Optics Mass Analyzer Detector Vacuum Pump Readout Electronics Algorithm/ Detection 4

5 System Features Low power non thermionic ionization system Electron tunneling using field emitter arrays Permanent magnet magnetic sector Does not use any power for mass separation Arrayed detector with an IonCCD Simultaneous detection of all ions. Short ion path length (ca. 5 cm) Higher pressure operation Lower power vacuum system System is not scanned or pulsed No loss of signal from duty cycle of ion source or mass filter/trap Simple/Rugged 5

6 Original Spectrometer Concept/Demonstrator Magnetic Sector 1T Permanent Magnet Scaled to detector Continuous injection No scanning Cu Target for Laser Desorption 6

7 Ardara Technologies Ionization Source High current with electron bias high current filament 70 ev typical 4-8 V diff e - flow +4-8 VDC bias over ion region Ion flux Detector Ion Region V typical 7

8 Advanced Electron Sources Fomani et al., TED 2014 Thick SiN / SiO insulator stack Htip 0.7 µm Gate Rap 1.5 µm Pt-coated emitter tip with improved stability 3 µm Si SiO SiN Poly-Si Single-gated Si field emitter arrays with 10 μm pitch (320K elements in 6mm 6mm active area) and 6 nm tip radius 8

9 NEMS CNT Electron Impact Ionizer IV Characteristics (ions) Highlights Max. Ionization Efficiency about 20% 21 mtorr operation ma-level electron current Ionization Eff. vs. Pressure 9

10 Ion Detector System IonCCD 3 μm 21 μm Read out circuitry and partial of 12 pixel Atomic Force Microscope picture of surface Wire bonded IonCCD on ceramic carrier The IonCCD is based on charge coupled device (CCD) technology. An added conductive layer creates capacitive charge detector elements. The IonCCD is optimized for the detection of positive ions. The IonCCD features 2126 active pixel over 5.1 cm Pixel dimension 1500 μm H X 21 μm W 88 % active area detection area Integration time = exposure time Currently integration from 80 μs to 5 s Read out time 2.4 ms serial read out of parallel pixel wells Readout time + exposure time = frame time 10

11 Simultaneous Detection of Spatially Resolved Ions Mass Spectrum of hexane 11

12 Ion Source with Entrance Lens Stack and Magnet Magnet Lens Stack Ion source Detector Array 12

13 Layout of Test Setup Ion source, ESA, Lens stack, and Assembly 3D printed parts: ESA, Lens Stack, outside holder Vacuum compatible Lens stack ESA Ion source (Ardara Technologies) 13

14 Chamber Design for Field Testing 14

15 First Ions Through System Intensity x10-5 Torr No lenses (H2O) Detector Position (mm) Active lens 9000 ESA Intensity Spectrum with 1 lens (a little more structure) Intensity Reference Spectrum from VQM (H2O) Detector Position (mm) mass-to-charge (Da) 15

16 Single Spectrum Data Dichloromethane Toluene Note Shoulder Note Shoulder Dichloromethane Toluene Working on improving resolution with lens optimization 16

17 Single Compound Spectra Show fairly stable response over time Exponentially Decreasing Sample Concentration 17

18 Multiple Compound Injections Isopropanol Dichloromethane Toluene 18

19 Acknowledgements The research is based upon work supported by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), via Air Force Research Laboratories contract FA C 9103, and work supported by Leidos Exploratory Research and Development Funding. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the ODNI, IARPA, or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright annotation thereon. 19

20 Abbreviations and Acronyms A Ampere(s) ca. circa/approximately CCD charge coupled device cm centimeter(s) Cu copper CNT carbon nanotube Da Dalton(s) diff differential e electron Eff efficiency ESA electrostatic analyzer ev electron Volt(s) GE gate to emitter H height H2O water Htip height of tip I(A) anode current I(I) ion current I(E) electron current IV Current versus Voltage ma milliampere(s) mm millimeter(s) ms millisecond(s) mtorr millitorricelli nm nanometer NEMS nanoelectromechanical system Rap radius of aperture foam micro foam m micrometer(s) s microsecond(s) IonCCD trade name for ion sensitive CCD s second(s) Si Silicon SiO Silicon oxide SiN Silicon nitride T Tesla(s) V Volt(s) VDC Volts direct current V(GE) gate to emitter voltage W width ZPMS zero power mass analyzer/spectrometer 20