US 11,876,015 B2
Method for transferring a useful layer to a carrier substrate
Didier Landru, Le Champ-près-Froges (FR); Oleg Kononchuk, Theys (FR); Nadia Ben Mohamed, Echirolles (FR); and Franck Colas, Tencin (FR)
Assigned to Soitec, Bernin (FR)
Appl. No. 17/435,631
Filed by Soitec, Bernin (FR)
PCT Filed Feb. 26, 2020, PCT No. PCT/FR2020/050369
§ 371(c)(1), (2) Date Sep. 1, 2021,
PCT Pub. No. WO2020/188169, PCT Pub. Date Sep. 24, 2020.
Claims priority of application No. 1902674 (FR), filed on Mar. 15, 2019.
Prior Publication US 2022/0157650 A1, May 19, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H01L 21/762 (2006.01); H01L 21/78 (2006.01); H01L 21/304 (2006.01)
CPC H01L 21/76254 (2013.01) [H01L 21/3043 (2013.01); H01L 21/7806 (2013.01)] 18 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;
d) annealing the bonded structure to apply a weakening thermal budget thereto and to bring the buried weakened plane to a defined level of weakening, the anneal reaching a maximum hold temperature; and
e) initiating a splitting wave in the buried weakened plane by applying a stress to the bonded structure, the splitting wave propagating in a self-sustained manner along the buried weakened plane to result in the useful layer being transferred to the carrier substrate;
wherein the initiation in step e) takes place when the bonded structure is experiencing a thermal gradient defining a hot region and a cool region of the bonded structure, the stress being applied locally in the cool region, and the hot region experiencing a temperature lower than the maximum hold temperature.