Patent ID: 11881429
Assignee: SOITEC
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
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 the carrier substrate;
c) joining the donor substrate, by the front face of the donor substrate, to the carrier substrate along a bonding interface so as to form a bonded structure;
d) annealing the bonded structure without initiating a splitting wave in the buried weakened plane by applying a weakening thermal budget thereto bringing the buried weakened plane to a defined level of weakening, the weakening thermal budget being less than a splitting thermal budget, the splitting thermal budget leading to spontaneous initiation of the splitting wave in the buried weakened plane during the annealing; and
e) after the annealing of the bonded structure to apply the weakening thermal budget, initiating the 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 splitting wave is initiated when the bonded structure is subjected, at least in its hottest region, to a temperature between 150° C. and 250° C.