Patent ID: 7449394

Claim:
A method for forming a semiconductor structure, which comprises: providing a donor wafer having a first semiconductor layer and a second semiconductor layer on the first layer and having a free surface; coimplanting two different atomic species through the free surface of the second layer to form a zone of weakness zone in the first layer; bonding the free surface of the second layer to a host wafer; supplying energy to detach at the zone of weakness a semiconductor structure comprising the host wafer, the second layer and a portion of the first layer; strengthening the bond between the second layer and the host wafer by heat treating the detached semiconductor structure at a temperature between 575° C. and 625° C. to provide a bonding energy that is greater than or equal to about 0.8 J/m 2 ; removing the first layer portion from the structure to expose a surface of the second layer; wherein the donor wafer comprises a SiGe layer, and the co-implantation of atomic species is conducted according to implantation parameters adapted to enable a first species to form the zone of weakness in the SiGe layer, and to enable a second species to provide a concentration peak located deeper in the first layer and beneath the zone of weakness in the donor wafer to thus minimize surface roughness resulting from detachment of the semiconductor structure at the zone of weakness, wherein the first species is hydrogen and the second species is helium.