The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 28, 2025
Filed:
Apr. 09, 2020
Fujikoshi Machinery Corp., Nagano, JP;
Fujikoshi Machinery Corp., Nagano, JP;
Abstract
A non-contact apparatus for measuring wafer thickness includes a monolithic wavelength sweeping semiconductor laser light source having a laser source, a laser control unit that controls the laser source, and a processor to control the laser source to oscillate laser light having a wavelength that changes with a setting profile relative to time; an optical system that guides and emits the laser light onto a wafer; a detection unit that detects an interference light signal of reflected light; an A/D converter that converts the interference light signal detected by the detection unit into a digital signal; and a calculation unit that calculates a thickness of the wafer by analyzing the digital signal from the A/D converter. The processor causes the laser control unit to operate with a clock signal, and to oscillate laser light that performs wavelength-sweeping with the setting profile relative to the time, from the laser source. The A/D converts the interference light signal by generating a sampling clock in synchronization with the clock signal or directly using the clock signal as a sampling clock.