Annealing behavior of clustercarbon™ implants

Abstract

We report here the use of a novel cluster carbon (C7H7+) implant along with n-type source drain dopant implants (As and P2) to form an embedded Silicon-Carbon (Si:C) layer. The implanted wafers were annealed using millisecond flash anneal (fRTP) followed by a post impulse spike RTP anneal (iRTP) for deactivation studies. The percentage of substitutional carbon ([C]subs) in the formed Si:C layer is characterized by a high-resolution x-ray diffraction (HRXRD) technique. The dependence of post spike anneal temperature on [C]subs show similar behavior for both As and P2 implants. With this clustercarbon implant approach the strain relaxation is only about 10% (90% strain retention) for the post spike anneal temperature of 1000°C. Higher flash anneal temperature leads to lower [C]subs. The sheet resistance is lower in the case of P2 implants when compared to As implants. We present here the detailed characterization of Si:C layer using HRXRD, SIMS, XTEM and activation of n-type dopants using SIMS and Rs measurements.