The Journey from Ω Through 19 Orders of Magnitude

Transcription

1 The Journey from Ω Through 19 Orders of Magnitude Presented at: 2013 NCSLI Conference and Symposium Nashville, Tennessee Personalize with title, slogan or I/B/P name in master slide Kai Wendler National Research Council Canada

2 Resistance Metrology Before 1990 Personalize with title, slogan or I/B/P name in master slide 2 12 May 2008 Dave Inglis, NRC Canada

3 Representation of the SI Ohm GaAs/AlGaAs sample on an H4 header Personalize with title, slogan or I/B/P name in master slide 3

4 Some Different Quantum Hall Devices 12 May 2008 Dave Inglis, NRC Canada 4

5 Hall devices from different wafers Rk-90 = Ω i = 1 Resistance (Ω) V0052 (1x10 18 cm -3 ) i = 2 V0054 (1.65x10 18 cm -3 ) Magnetic induction (T) 12 May 2008 Dave Inglis, NRC Canada 5

6 6 12 Personalize May 2008 with title, slogan or I/B/P Dave name Inglis, in master NRC Canada slide 6

7 Resistance and the SI Since 1990 Resistance has been represented in the SI by the quantum Hall effect (QHE). Rh = Rk-90 / i, where i is an integer coinciding with a plateau. Rk-90 = Ω Conventional value of Von Klitzing Constant Rk = h/e² Redefinition of SI important to resistance metrology! Personalize with title, slogan or I/B/P name in master slide 7

8 The Cryogenic Current Comparator From the QHR to an Artifact QHR CCC Resistance Standard

9 Bridge balanced when VR1 = VR2 CCC is self checking, can be used without resistors. Super conducting coils exhibit no leakage Basic design of all bridges is similar. Basic CCC bridge R 1 R 2 nv Meter I 1 I 2 + N 1 CCC N 2 + controller SQUID feedback N I 1 1 N2I2 = SQUID 0

10 CCC, pick-up coil and SQUID assembly.

11 Personalize with title, slogan or I/B/P name in master slide 11

12 NRC Uncertainties The CIPM MRA has now been signed by the representatives of 92 institutes from 52 Member States, 36 Associates of the CGPM, and 4 international organizations and covers a further 147 institutes designated by the signatory bodies.

13 CMC Calibration and Measurement Capabilities Peer review (NRC every 5 years) where a measurement expert examines: - Measurement theory and measurement system operation - Quality system - Competency and training - Thorough examination of uncertainties - Report Regional Metrology Organizations (SIM, EURAMET, APMP etc.) various NMI s and lastly CIPM participation in international key comparisons

14 NRC Uncertainties As a National Metrology Institute involved in measurement science at the highest level it is MSS policy to always and only report the experimentally determined uncertainty on the calibration certificate issued for any measurements. The values given for the measurement uncertainties shown in the Calibration and Measurement Capabilities CMCs (Appendix C) listing on the BIPM website are indicative of the results we would expect to achieve when calibrating a typical good quality client artifact under normal circumstances. It is possible that the uncertainty observed and reported may vary from the CMC value, in either sense..

15 From QHE to transfer standards QHR CCC 100 Ω 1 Ω CCC 100 kω 10 kω Personalize with title, slogan or I/B/P name in master slide 15

16 ESI 10k Fit data Fit value Long range drift Linear (Fit data) Fitted Value Deviation µω/ω This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner Jul Apr Jan Oct-06 6-Jul-09 1-Apr Dec-14 Date

17 Correct for temperature coefficient mathematically Rt = R ref [1+ 1 α(t-tref) + β(t-tref)²]

18 Power Coefficient This is the value at 0 ma fitted for 05-May a a1 5.80E-05 The value is mathematically corrected based on the current at which it is being used R5mA=R0mA-( x 5mA^2)

19 1 Ω Pressure Coefficients Maganin Resistor EvenOhm Linear (Maganin Resistor) Linear (EvenOhm) Dev. from dev at Std Pressure (uω/ω) 0.20 NIST 0.10 NRC El Paso TX Mexico City Pressure (kpa)

20 0.1 Ω to 10 kω

21 NRC Working Standards

22 In-house Inter-Comparisons NRC 1 Ohm DCC Bridge vs CCC fitted Value Fit Value Linear (Fit Value) Jan 21-Jan 26-Jan 31-Jan 05-Feb 10-Feb 15-Feb 20-Feb 25-Feb 02-Mar 07-Mar 12-Mar

23 Bridge Calibration DCC Bridge calibrated using CCC & transfer standards Power Coeficients NRC 10 Ω Resistor Deviation (µω/ω) Deviation vs Current Linear (Deviation vs Current) vs. 1 Ω vs. 100 Ω Current (ma)

24 The Importance of Bridge Calibration

25 0.1 Ω to Ω

26 DCC Bridge and :1 Range Extenders 5 A source DCC Bridge Scanner 100 A source 400 A source 10:1, 100:1, 1000:1 Range Extender 1000:1 Range Extender Standard Resistors in Oil Bath

27 Calibration of Range Extenders

28 Calibration of Range Extenders This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner

29 Calibration of Range Extenders

30 Calibration of Second Range Extenders (1000:1 Fixed) This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner

31 New Oil Bath for Shunts This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner

32 Mid Range 100 kω to 1 GΩ This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner

33 NRC High Resistance Scale CCC QH 10k 100k Dual Source Bridge 1G 100 T 10M 1G Wheatstone Bridge TeraOhmMeter

34 This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner

35 Use of Check Standards 10 M Calibration 15.0 Fitted Value vs Measured Value (k =2) fitted 10V V Deviation (µω/ω)

36 Improvement over time Historical Data for Client 1 MΩ Oil Resistor Deviation (µω/ω ) Jul Apr Jan Oct-06 6-Jul-09 1-Apr Dec-14 Date

37 1 G to 100 T

38 Dual Source Bridge V1 IImbalance R1 R1 / R2 = V1 / V2 V1 / R1 - V2 / R2 = I V2 R2 R1/R2 = V1 / V2 *( 1 R1* I / V1)

39 1.00 Dual Source Bridge Noise 0.50 Current (fa) This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner Time (s)

40 Small changes in current have a large influence I V R fa results in a change in value of slightly more than 100 ppm

41 High Resistance Uncertainties Resistance CMC Uc (µω/ω) ILC Uc (µω/ω) 1 G G G This sample slide shows how you can use imagery. If you are looking for interesting images specific to your presentation, contact: Harry Turner Personalize with title, slogan or I/B/P name in master slide 41

42 The Journey is over Thanks to: Dave Inglis Carlos Sanchez Francois Lemay Questions yes, But first a couple of important announcements! Personalize with title, slogan or I/B/P name in master slide 42

43 Resistance Metrology Tutorial NCSLI 2014 A course targeted for the folks in the lab & Kai Wendler NRC Personalize with title, slogan or I/B/P name in master slide Marlin Kraft NIST

44 HOT OFF THE PRESSES NCSLI 2014 How to Run a Successful Inter-Laboratory Comparison & Kai Wendler NRC Personalize with title, slogan or I/B/P name in master slide Georgette Macdonald NRC

45 Adieu Dave Inglis Dave will be retiring from NRC at the end of July Personalize with title, slogan or I/B/P name in master slide

46 Questions? Personalize with title, slogan or I/B/P name in master slide

47 INTERNATIONAL RESISTANCE COMPARISON Differences between laboratory and BIPM values, in ppm E. GERMANY (ASMW) AUSTRALIA (CSIRO) JAPAN (ETL) ITALY (IEN) USSR (IMM) FRANCE (LCIE) CHINA (NIM) USA (NIST) NORWAY (NMS) UK (NPL) CANADA (NRC) SWITZERLAND (OFM) W. GERMANY (PTB) SWEDEN (SP) NETHERLANDS (VSL) FINLAND (VTT) 1 ohm 10 kohm First international comparison of resistance standards between labs using QHE: 1 Ω & 10 kω Later attempts employed 100 Ω with varying success K12: Direct QHR:QHR is very good but expensive, and time-consuming. BIPM vs. LCIE, METAS, PTB, NPL, NIST: 1 nv ± 3 nv. K10: travelling 100 Ω, PTB after F. Delahaye, D. Bournaud and T.J. Witt, metrologia, vol. 29, 1992; "Report on the 1990 International Comparison of 1 Ω and 10 kω 12 May 2008 Dave Inglis, NRC Canada 47 Personalize Resistance with title, Standards slogan at the or BIPM" I/B/P name in master slide 47

48 Device NRC 1744F: 10 µa, 0.3 K re sista n ce /k magnetic induction/t Rh = Rk / i, where i is an integer coinciding with a plateau. Conventional value of Von Klitzing Constant Rk-90 = Ω Plateau # 2 used at NRC -well defined - resistance of Ω Independent of exact value of magnetic field or temperature and repeatable to parts in 10 e-10. Personalize with title, slogan or I/B/P name in master slide 48

49 Temperature Coefficient Thermal deviation of NML64150 from nominal Deviation from nominal ( µω/ω ) α (25) = ppm/c, β (25) = ppm /C Temperature (C) Personalize with title, slogan or I/B/P name in master slide 49

50 9.1E E-13 Current (A) 0.0E E E Time (s) Personalize with title, slogan or I/B/P name in master slide 50

51 NIST vs NRC 1G Expanded Uncertainty k=2 NIST NRC 1G Deviation (ppm) Personalize with title, slogan or I/B/P name in master slide 51

52 NIST vs NRC 100G Expanded Uncertainty k=2 Deviation (ppm) NIST 100G NRC 100G Personalize with title, slogan or I/B/P name in master slide 52

53 Leakage Paths V1 IImbalance R1 Leakage most likely with high voltage V2 Very low voltage in this path R2 Rleak ~ 1e14 to 1e15 Personalize with title, slogan or I/B/P name in master slide 53