Title:
EDDY CURRENT SENSOR
Document Type and Number:
Japanese Patent JP2017050381
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To improve accuracy of polishing end point detection by measuring film thickness in a narrower range.SOLUTION: An eddy current sensor 50 disposed in the vicinity of a substrate with which a conductive film is formed comprises a core part 60 and a coil part 61. The core part 60 includes a common portion 65 and four cantilevered portions 66-69 which are connected to the common portion 65. Ends of the first cantilevered portion 66 and the second cantilevered portion 67 are close and neighboring to each other. Ends of the third cantilevered portion 69 and the fourth cantilevered portion 68 are close and neighboring to each other. In the common portion 65, an excitation coil is disposed which is connected to an AC signal source 52. Both a first detection coil 631 disposed in the first cantilevered portion 66 and a second detection coil 632 disposed in the second cantilevered portion 67 detect an eddy current formed in the conductive film. In the third cantilevered portion 69, a first dummy coil 642 is disposed and in the fourth cantilevered portion 68, a second dummy coil 641 is disposed.SELECTED DRAWING: Figure 5
Inventors:
NAKAMURA AKIRA
Application Number:
JP2015172007A
Publication Date:
March 09, 2017
Filing Date:
September 01, 2015
Export Citation:
Assignee:
EBARA CORP
International Classes:
H01L21/304; B24B37/013; B24B49/10
Attorney, Agent or Firm:
Shinjiro Ono
Toru Miyamae
Yukio Kanegae
Makoto Watanabe
Koichi Kushida
Toru Miyamae
Yukio Kanegae
Makoto Watanabe
Koichi Kushida
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