High-Precision Thickness Measurement of Cu Film on Si-Based Wafer Using Erasable Printed Eddy Current Coil and High-Sensitivity Associated Circuit Techniques

2021 ◽  
pp. 1-1
Author(s):  
Zilian Qu ◽  
Wensong Wang ◽  
Zhengchun Yang ◽  
Qiwen Bao ◽  
Yuanjin Zheng
Keyword(s):  
High Precision ◽  
Eddy Current ◽  
High Sensitivity ◽  
Thickness Measurement ◽  
Current Coil ◽  
Cu Film ◽  
Circuit Techniques

Verification and Design of High Precision Eddy Current Sensor for Tip Clearance Measurement

2018 ◽  
Author(s):  
Ziyu Zhao ◽  
Zhenxia Liu ◽  
Yaguo Lyu ◽  
Xinxin Xu
Keyword(s):  
High Precision ◽  
Eddy Current ◽  
High Sensitivity ◽  
Response Speed ◽  
Measurement Range ◽  
Tip Clearance ◽  
Current Sensor ◽  
Eddy Current Sensor ◽  
Planar Coil ◽  
Sensor Coil

A high precision eddy current sensor for tip clearance measurement was proposed to assess the dynamic tip clearance measurement for aero-engine rotator. Based on the Lenz’s law, the eddy current sensor has high sensitivity, quick response speed and strong anti-interference capability, in addition, the simple geometry and easy installation are its main merits. The aim is to study the influence of planar coil structure parameters and excitation signal parameters on the sensor coil measurement, provide the basis for design of practical sensor in turbine tip clearance measurement. The dynamic calibration experiment verified the designed planar sensor coil, the results indicated the sensor resolution was 10μm and the measurement range was not less than 3mm. The dynamic experiment proved the measuring range, resolution, response speed of designed sensor can meet the requirement of turbine blade tip clearance measurement. The work provides experience in eddy current sensor design in different application, not only in turbine. And the future work will focus on the high temperature issues.

scholarly journals Evaluation of Coating Thickness Using Lift-Off Insensitivity of Eddy Current Sensor

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 419
Author(s):  
Xiaobai Meng ◽  
Mingyang Lu ◽  
Wuliang Yin ◽  
Abdeldjalil Bennecer ◽  
Katherine J. Kirk
Keyword(s):  
Eddy Current ◽  
Coating Thickness ◽  
Thickness Measurement ◽  
Eddy Current Testing ◽  
Thickness Variation ◽  
Testing Technique ◽  
Current Testing ◽  
Thin Skin ◽  
Embedded Algorithms ◽  
Lift Off

Defect detection in ferromagnetic substrates is often hampered by nonmagnetic coating thickness variation when using conventional eddy current testing technique. The lift-off distance between the sample and the sensor is one of the main obstacles for the thickness measurement of nonmagnetic coatings on ferromagnetic substrates when using the eddy current testing technique. Based on the eddy current thin-skin effect and the lift-off insensitive inductance (LII), a simplified iterative algorithm is proposed for reducing the lift-off variation effect using a multifrequency sensor. Compared to the previous techniques on compensating the lift-off error (e.g., the lift-off point of intersection) while retrieving the thickness, the simplified inductance algorithms avoid the computation burden of integration, which are used as embedded algorithms for the online retrieval of lift-offs via each frequency channel. The LII is determined by the dimension and geometry of the sensor, thus eliminating the need for empirical calibration. The method is validated by means of experimental measurements of the inductance of coatings with different materials and thicknesses on ferrous substrates (dual-phase alloy). The error of the calculated coating thickness has been controlled to within 3% for an extended lift-off range of up to 10 mm.

High-precision high-sensitivity clock recovery circuit for a mobile payment application

2011 ◽  
Vol 32 (5) ◽  
pp. 055007 ◽  
Author(s):  
Lichong Sun ◽  
Wenliang Ren ◽  
Na Yan ◽  
Hao Min
Keyword(s):  
High Precision ◽  
High Sensitivity ◽  
Clock Recovery ◽  
Mobile Payment

A novel flexible eddy-current probe with high sensitivity for NDT

2014 ◽  
Author(s):  
Ruifang Xie ◽  
Weihong Zhou ◽  
Dixiang Chen ◽  
Mengchun Pan ◽  
Ying Tang
Keyword(s):  
Eddy Current ◽  
High Sensitivity

Evaluation of 3D-Printed titanium alloy using eddy current testing with high-sensitivity magnetic sensor

2019 ◽  
Vol 102 ◽  
pp. 90-95 ◽  
Author(s):  
Dongfeng He ◽  
Zhi Wang ◽  
Masahiro Kusano ◽  
Satoshi Kishimoto ◽  
Makoto Watanabe
Keyword(s):  
Titanium Alloy ◽  
Eddy Current ◽  
High Sensitivity ◽  
Eddy Current Testing ◽  
Magnetic Sensor ◽  
Current Testing ◽  
3D Printed

scholarly journals Resolving Whether Inhalation of Depleted Uranium Contributed to Gulf War Illness Using High-Sensitivity Mass Spectrometry

2020 ◽  
Author(s):  
Randall Parrish ◽  
Robert Haley
Keyword(s):  
Mass Spectrometry ◽  
High Precision ◽  
Inhalation Exposure ◽  
High Sensitivity ◽  
Gulf War ◽  
Depleted Uranium ◽  
Isotopic Ratios ◽  
Gulf War Illness ◽  
Case Definitions ◽  
Standard Case

Abstract Background: Of the hypothesized causes of Gulf War Illness (GWI), a chronic multi-symptom illness afflicting approximately 25 percent of >700,000 military personnel deployed to the 1991 Gulf War, depleted uranium (DU) and exposure to nerve agents have stimulated the most intense international concern. Past depleted uranium research on Gulf War veterans has measured urinary uranium concentration [U] and uranium isotopic ratios with low precision mass spectrometry primarily in GW veterans with retained shrapnel but has not used high precision mass spectrometry to test for an association of GWI with inhaled DU and we set out to test this potential association. Methods: We applied a standard biokinetic model to predict the urinary total [U] and uranium isotopic ratios in urine 18 years after inhalation exposure. We applied high sensitivity mass spectrometry methods capable of detecting the predicted levels in 154 individuals of a population-representative sample of U.S. veterans in whom Gulf War illness had been determined by standard case definitions and DU inhalation exposures obtained by medical history. Results: Methods used in past studies are capable of detecting only the high urinary uranium excretion levels from retained DU shrapnel but not lower levels predicted from DU inhalation. Using high precision mass spectrometry, we found no difference in the 238U/235U ratio in veterans meeting the standard case definitions of GWI versus control veterans, and no differences by levels of DU inhalation exposure. Our bivariate analysis of 236U/238U by 235U/238U showed only the signature of natural dietary uranium, excluding DU inhalation exposures above 0.4 mg, far below the disease-causing threshold. Conclusion: The findings by high precision mass spectrometry support the conclusion that even the highest levels of DU inhalation played no role in the development of Gulf War illness. Other factors including exposure to aerosolized organophosphate compounds (pesticides and sarin nerve agent) remain as the most likely cause(s) of GWI.

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