摘要 |
<p>This invention relates to a method for making a thin layer starting from a wafer comprising a front face with a given relief, and a back face, comprising steps consisting of: a) obtaining a support handle with a face acting as a bonding face; b) preparing the front face of the wafer, this preparation including incomplete planarisation of the front face of the wafer, to obtain a bonding energy E<SUB>0 </SUB>between a first value corresponding to the minimum bonding energy compatible with the later thinning step, and a second value corresponding to the maximum bonding energy compatible with the subsequent desolidarisation operation, the bonding energy E<SUB>0 </SUB>being such that E<SUB>0</SUB>=alpha.E, where E is the bonding energy that would be obtained if the front face of the wafer was completely planarised, alpha is the ratio between the incompletely planarised area of the front face of the wafer and the area of the front face of the wafer if it were completely planarised; c) solidarising the front face of the wafer on the bonding face of the support handle, by direct bonding; d) thinning the wafer starting from its back face until the thin layer is obtained; e) transferring the thin layer onto a usage support, involving separation from the support handle.</p> |