Patent ID: 7276428

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; implanting atomic species through the free surface of the second layer to form a zone of weakness zone in the first layer, wherein the implanting includes implantation parameters chosen to minimize surface roughness resulting from detachment at the zone of weakness by providing a surface roughness relative to the second layer immediately after detachment that is less than about 40 Å RMS measured on a 10×10 μm portion of the surface; 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; conducting a bond strengthening step on the structure after detachment at a temperature of less than 800° C. to improve the strength of the bond between the second layer and the host wafer to reduce or avoid edge delamination; and selectively etching the first layer portion to remove it from the structure and to expose a surface of the second layer.