US 12,142,517 B2
Method for transferring a useful layer from a donor substrate onto a support substrate by applying a predetermined stress
Didier Landru, Le Champ-près-Froges (FR); Oleg Kononchuk, Theys (FR); and Nadia Ben Mohamed, Echirolles (FR)
Assigned to Soitec, Bernin (FR)
Appl. No. 17/436,532
Filed by Soitec, Bernin (FR)
PCT Filed Feb. 26, 2020, PCT No. PCT/FR2020/050367
§ 371(c)(1), (2) Date Sep. 3, 2021,
PCT Pub. No. WO2020/188167, PCT Pub. Date Sep. 24, 2020.
Claims priority of application No. 1902668 (FR), filed on Mar. 15, 2019.
Prior Publication US 2022/0172983 A1, Jun. 2, 2022
Int. Cl. H01L 21/762 (2006.01)
CPC H01L 21/76254 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method for transferring a useful layer to a carrier substrate, comprising the following steps:
a) providing a donor substrate including a buried weakened plane, the useful layer being delimited by a front face of the donor substrate and the buried weakened plane;
b) providing a carrier substrate;
c) joining the donor substrate, by its front face, to the carrier substrate along a bonding interface so as to form a bonded structure; and
d) applying a predetermined stress to the buried weakened plane for a period of time and annealing the bonded structure during the period of time in order to increase a level of weakening of the buried weakened plane, the predetermined stress being chosen so as to initiate a splitting wave once a given level of weakening has been reached, at an end of the period of time, the given level of weakening having been reached, the predetermined stress causing initiation and self-sustained propagation of the splitting wave along the buried weakened plane, resulting in the useful layer being transferred to the carrier substrate;
wherein the given level of weakening is based on an area of the buried weakened plane that is occupied by microcavities.