ClusterBoron Implant Alternative to BF2 PMOS SDE

As device geometries scale, the formation of the SDE becomes increasingly difficult and increasingly important. For advanced technologies, new methods such as ultra-low-energy boron implantation and millisecond annealing (flash or laser) are necessary to achieve the required junction characteristics. In addition, these processes must be compatible with the remainder of the process flow, which might include advanced dielectrics, stress technologies, SOI, etc. The emergence of ClusterBoron as a high productivity alternative for the low energy implant creates interest in device performance possible in a realistic process flow. This paper will present an evaluation of the use of ClusterBoron for the PMOS SDE in an advanced 65 nm logic process which includes laser annealing, e-SiGe stress layers and SOI. The conventional process uses a BF2 SDE process. Complete device characteristics will be shown comparing the ClusterBoron SDE to the conventional BF2. It will be shown that the ClusterBoron process achieves better boron activation, leading to enhanced transistor drive current. It will also be shown that the ClusterBoron is compatible with the SiGe stress layers and SOI structure. In summary, ClusterBoron presents an attractive alternative to the conventional BF2 process for advanced PMOS SDE.