Argus
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Argus Next Generation Hemispherical Analyser • Excellent Sensitivity • True Counting Multi-Anode Detector • Linear Response up to the Highest Count Rates • Excellent Dynamic Range • Snapshot and Dynamic XPS • Chemical State Mapping

Multitechnique system with the new Argus hemispherical analyser. Inside the new Argus hemispherical analyser: a multi-anode detector. ESCA+ system with the new Argus hemispherical analyser. 88 2 www.omicron.de

e- eeeeee- eeee-ee- e- ee-eee- e-ee- ee- e-e- eeeee-ee- Dispersive plane of energy analyser analyzer MCP Stripe anodes Ch 125 Ch 126 Ch 127 Ch 128 Ch 1 Ch 2 Ch 3 Ch 4 Pre-Amplifier Counters Readout Electronics Transfer to PC Fig. 1: Detector scheme: each electron impact starts a cascade of electrons propagating through the MCP stack. The amplified electron signals are collected by a stripe anode array which is connected to 128 dedicated amplifiers and counters. Dedicated in-vacuum readout electronics ensure fast data transfer to the ex-vacuum electronics. One Step BEYOND Conventional ESCA...

2 Peak Intensity [cps] 2 1.5 10 M 0 Counts [Mcts] Ag 3d5/2 20 M 0 100 200 x-Ray Power [W] 300 1 0.5 0 1200 1000 800 600 400 Binding Energy [eV] 200 0 Fig. 2 (left): Example of routine XPS measurement: survey spectrum of a clean silver surface Insert (above): Linear dependence between the increase of the X-ray power (DAR 400) and the detected count rate. Faster Analysis Argus ensures fast sample analysis with superior sensitivity compared to previous Channeltron detection systems. Besides Argus‘s highest sensitivity the key to modern sample analysis are dedicated detection modes such as...

3 7000 Fig. 3 Comparison of snapshot (black dots) and scanned (red curve) XPS spectra measured on a sample with gold islands on carbon. The narrow spectra of C1s and Au4f have been analysed quantitatively. Both scanned and snapshot modes yield identical results for the amounts of carbon and gold present on the surface. SnapShot Scan 6000 Counts 5000 4000 C1s Au4f 3000 2000 1000 0 290 285 280 90 85 Binding Energy [eV] 80 Atomic Concentration Scan Mode SnapShot Carbon 96.9% 96.9% Gold 3.1% 3.1% Scanning & Snapshot XPS Hemispherical analysers offering the snapshot mode allow for much faster...

4A 4B 5 500 µm 4C Fig. 4 A: Light dependent resistor before mounting. Fig. 4 B: See also page 9, Fig. 12. The sample structure can be easily identified when compared with the LDR image (4 A). Fig. 4 C: Fast survey spectrum showing the compounds of the LDR (Cd, S, In, Sn, O and C). Fig. 5: The LDR was part of an ex-vacuum serial circuit with a bias current and gated light source. The voltage drop across the LDR changes as soon as sufficient light hits its surface. For the experiment a gated LED (ton = 1 s) was used to switch the photoconductivity of the LDR. The changed local sample voltage...

Sample Temperature Snapshot Time Series Channel Number Spectrum Number Spectrum Number Fig. 6 & 7: The measurement shows the evolution of XPS spectra while remo- ving an in-situ grown Si02 layer on a Si substrate by ramping the temperature from 600 °C to 950 °C within one hour. More than 6000 snapshot spectra have been recorded with an acquisition time of 0.5 seconds per spectrum to follow the time evolution of the subcomponents Si4* to Si0 during the heating process of the Silicon. The complete removal of the oxide takes place within a very narrow temperature window around 850 °C. Fig. 8:...

10 11A 11 3 2 1 1 = Cadmium = Indium = Silver 500 µm Complex Chemical State Mapping The Argus input lens design includes proven scan deflector technology, allowing effortless, fast and reliable chemical state mapping of the sample. XPS maps provide full peak information including chemical shifts at each pixel (see fig. 11, 12 & 13). Instead of serially scanned plain peak (or peak-background) count rate detection (e.g. on the Cd 3d5/2 peak) the new multi-channel detector records a complete parallel view of the spectrum containing the XPS peak, tails and background at each pixel (see fig....

11B 11C 2 3 12 13 14 500 µm 500 µm 1 =S 2 = Sn 3 = Ni 1 = Oxide on Cd and NiCd 1 = Carbon contamination 2 = Oxide on ITO 2 = Carbon of the conductive polymer The Light Dependent Resistor (LDR) is a good example for today´s demand for accurate understanding of samples with complex local chemistry. In the present study the Argus was used to reveal the local sample information by chemical state mapping and local spectroscopy. Fig. 11) to 14) show 4 maps, each consisting of a RGB colour overlay of different elements (11 & 12) and chemical states (13 & 14). Each map includes 40.000 snapshot...

MATRIX for Electron Spectroscopy The MATRIX concept for spectroscopy gives a user friendly yet extremely powerful interface for experiment control and data acquisition. In addition MATRIX is the first commercial platform to offer combined SPM and electron spectroscopy experiments within the same software. All experiments will provide similar handling and workflows – a key for everyday life in a modern laboratory. The spectroscopy user interface immediately allows even inexperienced users to run the full range of experimental techniques through the intuitive control panel. A well organized...

Headquarters: Omicron NanoTechnology GmbH Limburger Str. 75 65232 Taunusstein, Germany Tel. +49 (0) 61 28 / 987 - 0 Fax +49 (0) 61 28 / 987 - 185 Web: www.omicron.de e-mail: info@omicron.de Minneapolis Pittsburgh East Grinstead Linköping Moscow Poznan Beijing We have agents and partners worldwide – please check our website to find your nearest contact. Seoul Tokyo Taipei Mumbai Omicron NanoTechnology is part of the Oxford Instruments Group. For more information: www.oxford-instruments.com or just send us an e-mail: info.plc@oxinst.com Singapore Denver Madrid St. Cannat Rome Bucharest...