Text optional: Institutsname Prof. Dr. Hans Mustermann Mitglied der Leibniz-Gemeinschaft Member of the Helmholtz Association High-Speed PIXE

Text optional: Institutsname Prof. Dr. Hans Mustermann www.fzd.de Mitglied der Leibniz-Gemeinschaft Member of the Helmholtz Association

High-Speed PIXEFast Elemental Analysis

with a Colour X-ray Camera

Josef BuchrieglerJ.v. Borany, D. Hanf, S. Merchel, F. Munnik, S.H. Nowak, A.D. Renno, O. Scharf, R. Ziegenrücker

ICNMTA, 11th July 2014, Padova

11th July 2014, Padova 2

Josef Buchriegler | Institute of Ion Beam Physics and Materials Research | www.hzdr.de/iba | [email protected]

Member of the Helmholtz Association© Google Earth

Dresden

Padova

Overview



Member of the Helmholtz Association

Outline

1. Motivation Needs for a new PIXE set-up, Competitive methods

2. Experimental set-upIBC-overview, High-Speed PIXE set-up, SLcam®

3. Data evaluationiXCC-Imager, GeoPIXE

4. First resultsLateral resolution, Trace element detection

5. Summary & Outlook




Motivation

Why new analysis methods should be developed?

urgent requirement for resource technology

for exploration, mining, sustainable use and recycling of mineral and metalliferous resources

due to:

rising energy costs

increasing environmental protection

requirements

declining quality of geogenic resources

growing demand for metalliferous raw

materials Source: Stephen Codrington




Motivation

How new analysis methods should be developed?

Foundation of Helmholtz Institute Freiberg for Resource Technology (in June 2011): joint venture between TU Bergakademie Freiberg & Helmholtz-Zentrum Dresden-Rossendorf

aim of the new institute:

research of new technologies designed

for:

utilize resources more efficiently

assure supply of raw materials

environmentally friendly

technologies




Motivation

Why a new PIXE analysis method should be developed?

Analytical chain for chemical analysis at Helmholtz Institute Freiberg:

fast

• X-ray fluorescence (XRF)• Mineral liberation analyser (MLA)

• Electron microprobe analyser (EPMA)• High-Speed PIXE lower background

• Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)*

• Ion microprobe (RBS, ERDA, PIXE, PIGE, NRA)

sensitiv

• Accelerator mass spectrometry (AMS)• Super-SIMS*

* under construction




Motivation

How High-Speed PIXE can be competitive?

fast laterally resolved elemental information

high sensitivity for trace elements (concentrations < 0.1 at.%)

high throughput

large/heavy samples

grain size determination, intergrowth analysis, etc.

High-SpeedPIXE

novel combination of

PIXE as analytical method

position sensitive detector pixel-detector

X-ray optics polycapillaries

fast data acquisition system

established evaluation software GeoPIXE




Experimental set-up

Ion Beam Center overview

Proton beam

Scanningsystem

Beam diagnosticchamber

Sample chamber

SLcam®

Dataacquisition

approximately 90 m from ion source to sample surface

2 – 4 MeV protons

up to 1 µA current

un-scanned spot-

size: 0.25 × 1.00

mm²

Opticalmicroscope

Quadrupole




Experimental set-up

High-Speed PIXE set-up

A. Renno, D. Hanf, O. Scharf

Proton beam

Scanningsystem

Beam diagnosticchamber

Sample chamber

SLcam®

Dataacquisition

Opticalmicroscope

Quadrupole

25 cm




Experimental set-up

Classical µ-beam set-up

Object50x50 μm2

Aperture1x1 mm2

Lens

Sample surfaceHigh-energyproton beam

(3 µA)

focused beam (1-5 µm) and scan across sample big detector as close as possible to sample

proton currenton sample: 0.5 nA

Sample surface

High-energyproton beam

(<1 µA)

broad beam use of pixel detector (pnCCD) local fields of view defined by suitable X-ray optics combining X-ray optics and pnCCD:

laterally resolved PIXE images

New approach: position sensitive detector & X-ray optics

Detector

X-ray g

uidance




Experimental set-up

Functional principle

sample surface tilted by 15°:

undistorted PIXE images

high X-ray yield

two types of polycapillary optics:

1. straight capillaries high depth of focus

2. conical capillaries 6:1 magnification

Ø 19 mm

82 mm

1.2 mm




Experimental set-up

SLcam®

12 cm

Name Value

number of pixel 264 × 264 = 69 696

pixels size 48 × 48 µm²

image area 12 × 12 mm²

frame rate 1000 Hz

sensitive energy range 2 – 20 keV

active sensor thickness 450 µm

energy resolution 152 keV @ Mn Kα

quantum efficiency>95% @ 3-10 keV>30% @ 20 keV

window 50 µm Be

X-ray opticsparallel (76 mm, 1:1)conical (82 mm, 6:1)




Data evaluation

iXCC-Imager: real-time data analysis (IFG X-Ray Colour Camera)

Geological sample “Kischa” (S04):70 minutes @ ~300 nA 22×106 events




Data evaluation

iXCC-Imager: real-time data analysis (IFG X-Ray Colour Camera)

~4 cm

Ti Kα Ca KβCl KαK KαMn KαSi Kα

12 mm




Data evaluation

Limits of iXCC-Imager: Overlapping peaks

Intensity

106

105

104

103

0 4 8 12 16 20 keV Energy

Geological sample “Columbite” (S20):4.5 hours @ ~300 nA 113×106 events

12 mm




Data evaluation

GeoPIXE: Established evaluation software for geological samples

Quantitative evaluation:• detector properties• sample properties (matrix)• corrections for the optics• X-ray line model• background model• pileup correction

Deconvolution of spectra

12 mm

GeoPIXE

iXCC




First results

Visual lateral resolution

Visual lateral resolution ~67 µm

intensity along green line

Measurement of known structures:

67 µm Cu-stripes on Si-waferspacing: 200 / 135 / 67 µm

Px

Cu-stripes (S08):97 minutes @ ~500 nA 363×106 events

pixel

3 mm




“Cr on Si” (S16):75 minutes @ ~400 nA 120×106 events

Sigmoid fits

Calculated lateral resolution

intensity perpendicular to Cr-edge

Cr-pattern on Si-wafer

First results

Line-Nr. Edge position Width (0.12-0.88)

67 95.09 0.9

68 95.21 1.3

69 95.08 1.4

70 95.00 1.5

71 94.96 0.9

72 94.93 1.5

73 94.79 2.3

74 94.79 1.4

75 94.81 2.2

76 94.92 2.2

77 94.86 1.7

78 94.71 1.6

Mean (94,93±0,15) px (1,58±0,47) px

Calculated lateral resolution: (76±23) µm

pixel




First results

Cassiterite (Tin Stone)proton energy: 3 MeVcurrent: ~ 700 nAmeas. time: ~ 45 min

Ta-Lα concentration map (<0.1 at.%)

Trace element detection in geological samples




Summary & Outlook

Summary

new PIXE set-up built at HZDR novel combination of SLcam® and PIXE motivation: resource technology comparison with competitive methods first assessment of lateral resolution promising results with trace elements

Outlook

o quantitative evaluation accurate fluence monitoring

o automation

o windowless operation lighter elements (Z<16)

o full integration of GeoPIXE:

concentration maps in real-time




Acknowledgements

This work is supported by Marie Curie Actions - Initial Training Networks (ITN) as an Integrating Activity Supporting Postgraduate Research with Internships in Industry and Training Excellence

(SPRITE) under EC contract no. 317169

Helmholtz-Zentrum Dresden-Rossendorf, Dresden

Shavkat Akhmadaliev

Johannes von Borany

Daniel Hanf

Silke Merchel

Frans Munnik

Axel Renno

René Ziegenrücker

Operator team

IFG Institute for Scientific Instruments, Berlin

Stanisław H. Nowak

Oliver Scharf

Thank you for your attention !

Documents

Text optional: Institutsname Prof. Dr. Hans Mustermann Mitglied der Leibniz-Gemeinschaft Member of the Helmholtz Association High-Speed PIXE