US 11,054,402 B2
Method and device for checking a bond between two substrates
Frank Fournel, Villard-Bonnot (FR); Ali Dekious, Castelnau-les-Lez (FR); Emilie Deloffre, Saint-Ismier (FR); Gilles Despaux, Saint-Georges-d'Orques (FR); Vincent Larrey, La Murette (FR); and Emmanuel Le Clezio, Les Matelles (FR)
Assigned to Commissariat à l'Energie Atomique et aux Energies Alternatives, Paris (FR)
Appl. No. 16/466,393
Filed by Commissariat à l'Energie Atomique et aux Energies Alternatives, Paris (FR)
PCT Filed Dec. 6, 2017, PCT No. PCT/FR2017/053420
§ 371(c)(1), (2) Date Jun. 4, 2019,
PCT Pub. No. WO2018/104666, PCT Pub. Date Dec. 9, 2016.
Claims priority of application No. 1662258 (FR), filed on Dec. 9, 2016.
Prior Publication US 2019/0353623 A1, Nov. 21, 2019
Int. Cl. G01N 29/46 (2006.01); G01N 29/04 (2006.01); G01N 29/11 (2006.01)
CPC G01N 29/46 (2013.01) [G01N 29/043 (2013.01); G01N 29/11 (2013.01); G01N 2291/015 (2013.01); G01N 2291/02827 (2013.01); G01N 2291/0427 (2013.01); G01N 2291/101 (2013.01); G01N 2291/267 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of evaluating quality of a bonding of an assembly comprising first and second substrates each having a front surface and a rear surface, the rear surface of the first substrate being bonded to the front surface of the second substrate, the method comprising the steps of:
a) transmitting an excitation ultrasound signal towards the assembly by means of an ultrasound transducer placed on the front surface side of the first substrate;
b) measuring, by means of said transducer, an ultrasound signal comprising at least one echo (EF1) of the excitation signal on the rear surface of the second substrate;
c) calculating, by means of a processing circuit, a general reflection coefficient defined as a ratio of a first signal representative of a frequency domain transpose of the ultrasound signal measured at step b), up to a second signal representative of a frequency domain transpose of the excitation signal; and
d) deducing from said spectral signal, by means of the processing circuit, information relative to the quality of the bonding between the first and second substrates.