US 11,928,178 B2
Method for creating wafer shape data
Masato Ohnishi, Fukushima (JP)
Assigned to SHIN-ETSU HANDOTAI CO., LTD., Tokyo (JP)
Appl. No. 17/268,326
Filed by SHIN-ETSU HANDOTAI CO., LTD., Tokyo (JP)
PCT Filed Aug. 1, 2019, PCT No. PCT/JP2019/030209
§ 371(c)(1), (2) Date Feb. 12, 2021,
PCT Pub. No. WO2020/049911, PCT Pub. Date Mar. 12, 2020.
Claims priority of application No. 2018-165807 (JP), filed on Sep. 5, 2018.
Prior Publication US 2021/0164770 A1, Jun. 3, 2021
Int. Cl. G06F 17/17 (2006.01); G01B 11/06 (2006.01); G01B 11/30 (2006.01); G01B 21/30 (2006.01); G06F 17/18 (2006.01)
CPC G06F 17/17 (2013.01) [G01B 11/06 (2013.01); G01B 21/30 (2013.01); G06F 17/18 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A method for creating wafer shape data in which data of a shape of a wafer is created with a function, the method comprising:
measuring a thickness shape at a position in a radial direction for each of a predetermined number of angles into which 360 degrees of a circumference around a center of the wafer are divided;
creating a function of a wafer thickness at the position in the radial direction for each of the angles by sixth or higher order polynomial approximation;
comparing the thickness shape outputted by a measuring machine and a thickness shape outputted by the function with each other, for each of the angles; and
setting the function for each of the angles to data representing the shape of the wafer after an error on an entire surface of the wafer has been confirmed to be not greater than a predetermined error; and
wherein thickness shapes outputted by the measuring machine for each of the angles are averaged, and an order of a polynomial for creating the function for each of the angles is determined based on a correlation coefficient obtained when the averaged thickness shape for each of the angles is approximated with a multi-order polynomial.