US 12,444,039 B2
Method and a system for characterising structures through a substrate
Wolfgang Alexander Iff, Domène (FR); and Alain Courteville, Congenies (FR)
Assigned to UNITY SEMICONDUCTOR, Montbonnot-Saint-Martin (FR)
Filed by UNITY SEMICONDUCTOR, Montbonnot-Saint-Martin (FR)
Filed on May 1, 2024, as Appl. No. 18/651,957.
Application 18/651,957 is a continuation of application No. 18/319,281, filed on May 17, 2023, granted, now 12,079,979.
Claims priority of application No. 22305745 (EP), filed on May 19, 2022.
Prior Publication US 2024/0281955 A1, Aug. 22, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. G01N 21/88 (2006.01); B81C 99/00 (2010.01); G01B 11/22 (2006.01); G06T 7/00 (2017.01); G06T 7/521 (2017.01); G06T 7/60 (2017.01)
CPC G06T 7/0004 (2013.01) [B81C 99/003 (2013.01); G01B 11/22 (2013.01); G06T 7/521 (2017.01); G06T 7/60 (2013.01); G06T 2207/30148 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for characterizing structures etched in a substrate, such as a wafer, wherein a bottom of the structures is embedded in the substrate opposite to the structure etched in the top side of the substrate, the substrate having a top side in which the structures are etched and a bottom side opposite to the top side, the method comprising the following steps:
illuminating a bottom of at least one structure etched on the top side of the substrate with an illumination beam transmitting through the substrate issued from a light source arranged at the bottom side of the substrate and emitting light with a wavelength adapted to be transmitted through the bottom side of the substrate;
acquiring, with an imaging device positioned on the bottom side of said substrate, at least one image of a bottom of said at least one structure through the substrate; and
measuring at least one data, called lateral data, relating to a lateral dimension of the bottom of said at least one structure from the at least one acquired image.