Patent ID: 11951588
Assignee: EBARA CORPORATION
Field: Measurement (Instruments)
Classification: CPC B  G | IPC B  G

Claim 9:
10. An optical film-thickness measuring apparatus to be installed in a polishing apparatus for a workpiece, comprising:
a light source;
a light-emitting optical fiber cable coupled to the light source;
a light-receiving optical fiber cable arranged to receive light reflected from the workpiece;
a spectrometer configured to measure intensity of the reflected light at each of the wavelengths of the reflected light;
a data processing device configured to calculate a film thickness of the workpiece from measurement data of the intensity of the reflected light;
a first cable housing having a circular cross section, the first cable housing surrounding the light-emitting optical fiber cable and the light-receiving optical fiber cable;
a flow-passage structure defining a fluid passage adjacent to the light-emitting optical fiber cable and the light-receiving optical fiber cable, the light-emitting optical fiber cable and the light-receiving optical fiber cable being supported by the first cable housing and the flow-passage structure, the light-emitting optical fiber cable comprising a bundle fiber cable including multiple fiber cables which are arranged around the light-receiving optical fiber cable; and
a second cable housing surrounding the light-emitting optical fiber cable, the light-receiving optical fiber cable, and the first cable housing.