Local control of strain in SiGe by ion-implantation technique

Ion-implantation technique was developed as a local strain controlling method, where SiGe layers were formed on selectively ion-implanted Si substrates. By utilizing micro Raman measurements it was obviously found that the compressive strain of SiGe was almost relaxed only in the implanted region while the strain largely resides in the unimplanted region. This observation clearly demonstrated that the selectively and locally strain-controlled SiGe layer can be realized by this technique. It was also found that size reduction of the selective ion-implantation line pattern modified the strain states, implying that a uniaxial strain arose in the SiGe layer. These results suggested that this method is very promising for realization of high mobility channel devices based on local strain technique.