Hiden EQP Systems. High Sensistivity Mass and Energy Analyzers for Monitoring, Control and Characterization of Ions, Neutrals and Radicals in Plasma.

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1 Hiden EQP Systems High Sensistivity Mass and Energy Analyzers for Monitoring, Control and Characterization of Ions, Neutrals and Radicals in Plasma.

2 HIDEN EQP PLASMA DIAGNOSTIC SYSTEMS The Hiden EQP System is an advanced plasma diagnostic tool with combined high transmission ion energy analyzer and quadrupole mass spectrometer, acquiring both mass spectra at specified ion energies and ion energy distributions of selected plasma ions. The advanced EQP ionizer provides for neutral and radical detection, the electron attachment ionization feature further enhancing the detection capability for radicals in electronegative plasma chemistries. High Sensitivity Sub PPM detection of ions, neutrals and radicals. Ion Energy Analysis Ion Energy distributions of plasma ions are acquired in seconds, 100 ev and 1000eV energy range versions are available. The EQP is externally floatable to 10KeV. Afterglow, Pulsed Plasma, and Laser Ablation A standard TTL signal gating input is included for time resolved studies. Plasma pulses and plasma plumes with duration as short as 1 microsecond can be analysed. Positive and Negative Ion Measurement Pre-set software modes provide for instant switching between positive ion, negative ion and neutrals analysis modes. Neutral and Radical Detection The EQP integral electron impact ionizer provides for analysis of neutral and radical species Appearance Potential Spectra The EQP ionizer features precision control of all ion source parameters, including the facility to accurately scan electron energy, for appearance potential spectra of selected species. The appearance potential spectra provide direct information to confirm the fragmentation and excitation state of plasma neutral species. Electron Attachment Ionization Feature A new technique of soft ionization offered as an option for the analysis of electronegative species in plasma, further enhancing the analysis of neutrals and radicals. EQP Operating Modes Ion Energy Distributions of selected +ve and -ve ions. Mass Spectra at selected ion energies for +ve ions, -ve ions and neutrals. 5 lpm CO2, Plasma Reactor: 1 Torr Appearance Potential: mass 32 CF3- Ions By Attachment in CF4 SEM: c/s W plasma metastable O2 excited state a 1 g no plasma ground state O2 X 3 ḡ electron-energy: V Appearance potential spectra for identification of radical species from parent stable molecules. Electron attachment ionization scans to identify radical species produced in the plasma from electronegative gases.

3 HIDEN EQP DATA Ion Energy Distribution (IED) The ion energy distribution for ArH + from an Argon plasma sampled through the RF driven electrode of a parallel plate plasma chamber. The data shows the well known saddle structure attributed to the RF component of the plasma potential and VB, the self bias on the electrode. Negative and Positive Ion Mass Spectra The mass spectra shown are from analysis of Fullerene C60 A amu Fullerene mass spectrum of neutrals. Fullerene positive ions. Fullerene negative ions. Plasma Characterization The data show Ion Energy Distributions (IEDs) for O2 + ions from a MHz Argon/Oxygen plasma with power density 4Wcm -3. As the gas pressure increases ion collisions cause the ion energy to reduce. The EQP Ion energy distributions clearly identify the changing ion energy as the processing pressure is increased from 5 x 10-2 torr (5Pa) to 1.3torr (130Pa) Normalised Count Rate 130 Pa 50 Pa 20 Pa 5 Pa 10 Pa 15 Pa (Data courtesy of M. Zeuner and J.Meichsner, Chemnitz University of Technology,Germany.) Ion energy (ev) End Point Detection The EQP is a high sensitivity end point detector in reactive ion etching (R.I.E.).The data shows end point detection in the processing of a hetero junction device. The intensity change of the Aluminium ion signal, monitored at mass 27 during the SiCl4 etch, precisely identifies the 50Å AlGaAs layers in the multilayer structure. The complete etch is shown for clarity. In fabrication the etch is terminated at the optimum end point. Intensity 1000Å 50Å 100Å 50Å Aluminium m/z Å GaAs 50Å AIGaAs 100Å GaAs 50Å AIGaAs 4000Å GaAs 4000Å (Data courtesy of DRA, Malvern, UK.) Time (seconds)

4 Time Resolved Mass and Energy Spectra for Afterglow, Pulsed Plasma and Laser Ablation Studies. Reference Pulse T3 T4 Plasma Time Variation Gating Pulse Main Plasma T1 T2 After Glow Signal Acquisition The EQP system has a signal gating facility to enable control of data acquisition. Mass and Energy spectra can be acquired in any specified time window as short as just one µsecond. This example shows mass spectra for negative and positive ions from a plasma pulsed at 1kHz in silane deposition studies. Data courtesy of Herbert Meuller, Alan Howling and Christoph Hollenstein EPFL Lausanne Switzerland EQP MASsoft Software Operating Modes include: The EQP includes software pre-set modes for positive ion, negative ion, and neutrals analysis. Histogram spectra for mass scanning any mass window within the mass range. Profile mode for mass scanning with 0.01 amu increment over a user selectable mass window. Minimum increment is 0.02 amu for the full 1000 amu mass range EQP and 0.05 amu for the full 2500 amu mass range EQP. Background subtraction, providing subtraction of a designated spectrum from real time acquired data. Background subtraction operates for mass, energy and electron energy spectra. Trend analysis with real time plotting of peak intensities on a time axis, with tabular and graphical data views plotted simultaneously. Up to 100 mass channels can be programmed. Each mass channel peak can have its own mass spectrometer parameter set providing the capability for analysis of positive ions, negative ions and neutrals within the same trend analysis. Mixed mode scanning, for simultaneous scanning and display of ion energy distributions together with mass spectra. All functions are controlled from MASsoft, a single application in Windows, compatible with: Win 3.1x, Win NT, Win 95, and Win 98. Data export facilities to ASCII files and Windows supported output devices. Programmable Dynamic Data Exchange DDE to provide for direct use of data in other Windows client compatible applications, Excel for example. Map mode for continuous display of mass selected ion intensity as a function of selected lens parameters. Electron energy scanning of a mass selected ion intensity for determination of appearance potentials and differentiation of radicals from a parent stable neutral molecule. Energy scanning for obtaining ion energy distributions for selected masses. Automatic tuning and on-line manual tuning of all lens parameters under slide bar control. Review historical data simultaneously with data acquisition.

5 HIDEN s EQP - The Mass/Energy Analyzer for Plasma Diagnostics and Characterization Energy Analyzer The EQP high transmission energy analyzer provides ion energy distributions of plasma ions. The ion energy distribution identifies the energy with which each species is interacting with the substrate-critical information, in low damage etch for example. A 45 degree sector field energy analyzer is used in preference to a CMA or Bessell box in line analyzer for maximum transmission and to provide minimum perturbation to the ion flight path within the analyzer for optimum energy resolution. The EQP energy analyzer provides constant transmission and constant energy resolution functions throughout the ion energy range (+/- 100eV, +/-1000eV) The energy resolution of the sector field energy analyzer is better than 0.25eV FWHM. Energy scanning for selected ions is automatically controlled with energy increments selectable from 0.05eV. The EQP system is floatable to 10KeV using external power supplies and isolation components. Plasma Sampling Interface A range of laser drilled orifice diameters from 30µm diameter provides for sampling of +ve ions, -ve ions, neutrals and radicals. The orifice design is optimized for plasma sampling using pre-thinned material for the laser drilled component. Each orifice is helium leak tested to ensure correct conductance. Software controlled ion extraction optics provide for plasma sampling with minimum perturbation to the plasma. A standard connection is included in the EQP electronics to allow the EQP system to be referenced to an external supply, a plasma electrode for example. This feature enables ion energy distributions to be referenced to the substrate's self bias. Plasma electrodes coupled to the EQP provide a substrate platform for sampling the plasma exactly as it interacts with the substrate during processing. Electrodes are custom designed to suit RF, DC or pulsed plasma supplies with heated substrate stages and water cooling options available. The EQP sampling configuration can be readily disassembled for ionizer filament replacement and cleaning, the open design construction making maintenance a routine in-house procedure. Plasma Sampling Interface with Internal Ionizer Insertion up to 750mm EQP energy resolution Sector Field Energy Analyzer FWHM 0.24ev Penning Gauge Turbo Pump Water cooled RF/DC electrode Pulse Ion Counting Detector RF Generator Backing Line Triple Filter Mass Analyzer Plasma research system HPR-60 atmospheric pressure plasma sampling system Internal Ionizer The internal EQP ionizer includes two oxide coated iridium filaments, with a radially symmetric cage assembled in a close coupled configuration to the plasma sampling orifice for high sensitivity analysis of plasma gas neutrals and radicals. EQP software provides for precision control of the ion source operating parameters including filament emission, source cage voltage and the ionizing electron energy. A key feature of the EQP ionizer design is the confinement of electrons within the ion cage vicinity ensuring the high degree of control of the ionising environment necessary for the detailed appearance potential measurements used in the analysis of radicals. Electron attachment ionization option. An enhancement of the ion source control provides for analysis of negative ions produced in the EQP ionizer by electron attachment where electronegative species are present. This technique provides valuable information for the analysis of radical species in electronegative plasma. Mass Analyzer A triple filter mass analyzer construction is included in the EQP system. The triple mass filter has short 'RF only' pre and post filters which minimize effects from fringe fields at the primary mass filter ion entrance and exit, enhancing peak separation and transmission particularly for high mass species. This triple filter configuration has been proven superior in performance to single filter quadrupoles in recent years. Abundance sensitivity is to 0.1PPM. Detection to 20PPB is available for non-interfering species. The mass filter rods are precision ground from molybdenum with precision machined radially supporting ceramics for high performance, durability and long term stability. Mass filter pole diameters of 6mm and 9mm are offered to suit mass ranges of : 300, 510,1000, and 2500 amu. The mass filter is powered from solid state RF/DC power supplies. A 5Watt direct coupled compact unit is included for 6mm pole diameter systems, a 200Watt remote system is included for 9mm pole systems. Detector A pulse ion counting detector is included as standard offering seven decades continuous dynamic range. Counting is via a 24 bit counter for 1c/sec resolution throughout the range. A Faraday cup option extends the range up to 5 x c/s for high density plasma applications. The EQP software provides for data acquisition as raw counts, counts per second, averaged counts per second or integrated counts. Averaging or accumulating counts over repeated mass and energy scans significantly increases signal to noise in the analysis of minor components. A TTL output of raw counts is available via a connector on the EQP electronics system. A signal gating input is included as standard to provide for time resolved plasma studies with a resolution of 1µsecond suited to pulsed plasma or laser ablation applications, where energy and mass distributions of selected species can be analyzed at prescribed intervals across the plasma afterglow or plasma plume.

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7 EQP Specification Mass Range options. : 300 amu, 510 amu, 1000 amu, 2500 amu Sampling Range : Up to 0.5 mbar with 60 l/sec turbomolecular pump. Up to 2mbar with 240 l/sec turbomolecular pump Up to Atm. pressure with HPR 60 molecular beam sampling option. Mass Resolution : Defined as peak width at a % peak height. Standard settings: Mass ranges 300amu, 510amu, 1000amu. : 1amu at 5% peak height throughout the mass range. Mass range 2500 amu. : 1 amu at 10% peak height at 28 amu. 4 amu at 10% peak height at 2500 amu. Software adjustable for high resolution applications. Detector : Ion Counting detector. Positive and negative ion detection. 24 bit resolution counting electronics. Detector Range with electron multiplier detection : 1c/s to 10 7 c/s with optional Faraday/electron multiplier detection : 1c/s to 5 x c/s Signal Gating : Detector gating by direct TTL input, gating resolution to 1µ second. Energy Analyzer : 45 sector field. Energy range 100 ev (1000 ev optional). Energy resolution < 0.25eV FWHM. Transmission 100% within pass band. Ion Source : Electron impact, radially symmetric with twin filaments. Mass Filter : 3 stages each of 4 poles. Pole diameter: EQP 300/500 systems 6.00mm. EQP Series 1000 systems 9.00mm. Bakeout Temperature : 250 C Vacuum Protection : External trip for remote protection. Internal trip operative in RGA mode only. Mounting Flange : DN-63-CF 114mm OD ( 4 1/ 2 inch) Conflat type flange. Probe Insertion : Sampling orifice up to 750mm from the probe mounting flange RC 7 Plasma/SIMS : Height - 315mm/7U Interface Unit Width - 19 inch rack mounting Depth - 450mm Power Requirement : Vac, Hz, 1.0 kva Other Plasma diagnostics products from Hiden include: The ESPion Langmuir probe for electrical characterization of plasma including automatic analysis of: Plasma Potential. Ion and Electron Densities. Electron Energy Distribution > 5 orders resolution. Electron Temperature. Debye length. Floating Potential. ESP system with computer controlled Z-drive The Hiden ESPion Langmuir probe includes new advanced data analysis features developed together with independent calibration of the analysis by the plasma oscillation probe method, ensuring the best confidence factor available in Langmuir probe measurements. ESPion Windows software provides for trend analysis of plasma parameters as a function of time and position across the plasma volume.

8 Hiden EQP System ordering information. The Hiden EQP system comprises: EQP analyser with UHV differential pump housing, interchangeable sampling orifice, ion extraction optics, electron impact ioniser with two filaments, sector field energy analyser and triple filter mass analyser. RC7Plasma/SIMS interface unit for positive and negative ion detection. RF Generator with 3 m conduit cable. Windows MASsoft PC software. A Pentium PC with Win 98, Win NT, Win 2000, Win ME or Win XP is required for system operation. EQP 300 system, 300amu, Part Number EQP 500 system, 510amu, Part Number EQP 1000 series system, 300amu, Part Number EQP 1000 series system, 510amu, Part Number EQP 1000 series system, 1000amu, Part Number EQP 1000 series system, 2500amu, Part Number The EQP 1000 series includes Hiden s 9mm pole diameter triple filter quadrupole assembly and type C 200 watt RF providing a factor >5 improvement in sensitivity compared to EQP 300 and 500 systems, and offering extended mass range capability. Hiden s Plasma Workstation featuring an EQP 1000 setup Manufactured in England by: HIDEN ANALYTICAL LTD 420 EUROPA BOULEVARD WARRINGTON WA5 7UN ENGLAND Tel: +44 (0) Fax: +44 (0) info@hiden.co.uk Web site: It is Hiden Analytical s policy to continually improve product performance and therefore specifications are subject to change. TECHNICAL DATA SHEET 149 Printed in England