US 12,467,741 B2
Measurement method and measurement apparatus for measuring thickness of semiconductor wafer
Hiroyuki Itoh, Aichi (JP); Atsushi Morosawa, Aichi (JP); and Keiji Isamoto, Aichi (JP)
Assigned to santec Holdings Corporation, Aichi (JP)
Filed by santec Holdings Corporation, Aichi (JP)
Filed on Mar. 27, 2023, as Appl. No. 18/190,567.
Claims priority of application No. 2022-059800 (JP), filed on Mar. 31, 2022.
Prior Publication US 2023/0349688 A1, Nov. 2, 2023
Int. Cl. G01B 11/06 (2006.01); G01B 9/02 (2022.01); G01B 9/02015 (2022.01)
CPC G01B 11/06 (2013.01) [G01B 9/02016 (2013.01); G01B 9/02084 (2013.01); G01B 2210/56 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A measurement apparatus for measuring a thickness of a semiconductor wafer comprising:
an optical system configured to perpendicularly irradiate each of a sample wafer, which is a semiconductor wafer to be measured, and a reference wafer, which is a semiconductor wafer having a uniform thickness, with light to receive interference signals of the light reflected on front and back surfaces of the sample wafer and the reference wafer;
a signal processor configured to perform frequency analysis of the interference signals received by the optical system to obtain peak positions of point spread functions of the sample wafer and the reference wafer;
a calculator configured to calculate a thickness “tsample” of the sample wafer based on the peak position “x” of the sample wafer and the peak position “y” of the reference wafer obtained by the signal processor, and the thickness “treference” of the reference wafer; and
a temperature adjustment mechanism configured to adjust at least one of temperatures of the sample wafer and the reference wafer.