Boosting Ge-epi N-well Mobility with Sn Implantation and P-well Mobility with Cluster-C Implantation

We investigated the effects of Sn, Si and cluster-C implantation into both P-well and N-well doped regions of 100nm Ge-epilayer on Si wafers after RTA annealing. For the P-well case a 7.3x increase in Hall bulk mobility to 3384cm2/Vs with cluster-C implant and for the N-well case a 4.6x increase in Hall bulk mobility to 2062cm2/Vs with Sn implant. Measuring layer mobility depth profiles shows mobility in the top 10–20nm of the surface can be up to 6000cm2/Vs for N-well with Sn implant and >10,000cm2/Vs for P-well with Sn implant.