Novocontrol Alpha Analyzers Fundamentals

1. Novocontrol Alpha Analyzers Fundamentals Dirk Wilmer Novocontrol Technologies

2. Novocontrol Technologies GmbH & Co. KG Top-class impedance analyzers with test interfaces for various applications Reliable sample environment for various temperature ranges and pressure variation Turnkey Dielectric and Impedance Spectrometers Sample cells for a large variety of applications Software for instrument control, automation, and data analysis

3. Principle of measurement Voltage Current harmonic base waveFourier transform over n periods Permittivity Conductivity d electrode spacing, A electrode area

4. Impedance Measurement Requirements for Dielectric Measurements • Broad frequency range • Wide impedance range • Small loss factors tan(d) = e’’ / e’ = Zs’ / Zs’’ Sample is in first order approximation a capacitor Capacitive impedance Z = j / (wC) Relaxation usually adds small changes in Z DC conductivity adds parallel resistance

5. Parallel Representations: Same Voltage in Re, Im Admittance Parallel Imp. Serial Representations: Same Current in Re, Im Serial Imp. Loss Factor

6. Requirement Impedance Range Typical dielectric sample e’ C0 = 100 pF tan(d) = 10-4..1

7. Alpha-A modular measurement system

8. Impedance analyzer system highlights Broad frequency range 3 µHz .. 40 MHz (> 13 decades) Ultra wide impedance range 10-4 .. 1014 Ω (18 decades) covers range from conductors to best isolators in a single instrument set-up Ultra wide capacity range 10-15 .. 1 F allows broadband measurement of smallest capacities down to 1 fF.  High phase accuracy (2.10-3 °) and loss factor tan(δ) absolute accuracy (3.10-5) for low loss dielectric materials and isolators broadband characterization. Supports non-linear Dielectric, Conductivity and Impedance Spectroscopy or gain phase measurements in combination with all test interfaces.

9. Measurement examples Alpha total impedance range Typical results covering 18 orders of magnitude dynamics

10. Impedance analyzer system highlights High speed measurements for online monitoring of time-dependent processes in the 5 ms range (with Option F) Automatic self calibration and diagnosis by user compensates long term internal drift and verifies functionality. Precision digital frequency response analyzer up to 40 MHz for two channel gain phase measurements with 0.001° phase - and 10-5 in amplitude resolution included. Operates like a broadband lockin amplifier with two channels, extended accuracy and frequency range. Optional control WinDETA software for turnkey calibration, operation, data evaluation, 2- and 3- dimensional graphical representation including non linear spectroscopy.

11. Alpha-A: impedance measurements up to 40 MHz Alpha-AT+ZG4 RC network standard test sample New Alpha-A signal generator Improved calibration procedures 40 MHz also available for ZG2 and ZGS

12. Higher harmonics k = 1: first harmonic (or base wave)

13. HVB 4000: new high voltage test interface for the Alpha-A modular measurement system Dielectrics, semiconductors or electronic components at high AC and/or DC voltages for • non-linear dielectric / impedance spectroscopy; • characterization of materials or components under stress; • extremely high impedance samples exceeding 1014 Ω. Materials measurements: Novocontrol High Voltage Sample Cell Earlier products: - HVB 300 (3 µHz to 1 MHz, 300 Vpp AC and/or DC) - HVB 1000 (3 µHz to 10 kHz, 1000 Vpp AC and/or DC)

14. HVB 4000: new high voltage test interface for the Alpha-A modular measurement system Frequency: 3 µHz ... 10 kHz (9.5 decades) Impedance:1kΩ .. 2·1015 Ω (12 decades) Capacitance:  1 fF ... 0.01 F (13 decades)  Loss factor tan(δ):10-5 .. 104 AC signal out: 30 mV .. 2000 Vp, 2.7 mA max DC bias out: -2000 VDC .. +2000 VDC,  2.7 mA max Output impedance: 750 kΩ Voltage in: max. ± 2000 Vp dc coupled

15. Electrochemical Impedance Measurements (EIS) • Defined DC Voltage / Current referred to a third (differential) reference electrode • Potentiostat/Galvanostat function for defined cell DC polarization • DC measurement • Superimposed AC voltage / current for impedance measurement • Classical applications Interface polarization Intrinsic electrolyte conductivity RC Layer structures • Phase accuracy, impedance range not as critical as for dielectric measurements? • Additional applications: Ion conductivity, relaxation, sensors, fuel cells

16. POT/GAL: electrochemical test interfaces for the Alpha-A modular measurement system Reliable impedance measurements up to 1 MHz Very wide impedance range: 10-4W up to 1013W Variable output resistance Sample protection:high-power counter electrode signal output supports fast voltage and current limiters independent of the main control loop. Both voltage and current limits continuously adjustable and operate simultaneously in both potentiostat and galvanostat mode. Two models: 30 V/2 A and 15 V/10 A

17. POT/GAL: electrochemical test interfaces for the Alpha-A modular measurement system 4 channel 24 bit digitizer for simultaneous dc signal measurements of the counter-, two reference- and the working electrodes. High accuracy working electrode current input converter with reference technique for accurate measurement of both strong conductors and insulators. Non-linear EIS by higher harmonic measurements both on instrument and WinDETA application software level.

18. POT/GAL: electrochemical test interfaces for the Alpha-A modular measurement system Automaticdc level shifters at the working and reference electrodes inputs compensate dc voltage and current offsets in order to accurately measure the small superimposed ac signals for EIS. Supports real-time measurements by up to 150 impedance data points / second (option) and 1.500 voltage current data points / second in time domain mode.

19. An important competitor: specification No high-impedance measurements Limited phase and tan(d) resolution Limited usabilityat f>10 kHz

20. POT/GAL: electrochemical test interfaces for the Alpha-A modular measurement system 4-wire impedance mode accuracy