Patent ID: 8252663
Filing Date: 2012-08-28
Classification: H01L

Abstract:
1. A method of transferring a thin layer from a source substrate to a target substrate, wherein the source substrate includes a surface layer along a free surface thereof, the surface layer comprising a first material, and wherein the target substrate includes at least one surface layer along a free surface thereof, the one surface layer comprising a second material different from the first material, the method comprising: forming within the surface layer of the source substrate a weakened zone delimiting a thin layer with respect to the free surface; assembling the free surface of the source substrate with the free surface of the target substrate in a stack of alternating layers comprising the first and second materials so that layers of the first and second materials are on either side of an interface formed by bringing the free surfaces into intimate contact, wherein a cumulative thickness of the layers of the first material on a first side of the interface is substantially equal to a cumulative thickness of the layers of the first material on an opposite side of the interface and a cumulative thickness of the layers of the second material on the first side of the interface is substantially equal to a cumulative thickness of the layers of the second material on the opposite side of the interface, each of the alternating layers having thicknesses of at least 50 microns and at least 1000 times the depth at which the weakened zone is formed in the surface layer; and applying at least partially thermal energy to fracture the weakened zone and to detach the thin layer.