Simple structured PMOSFET fabricated using molecular layer doping

The application of molecular layer doping (MLD) to the formation of shallow source and drain regions of a PMOSFET is discussed. The MLD process consists of three steps. First, the natural oxide on the Si surface is removed by thermal cleaning to expose an active Si surface. Second, a boron adsorbed layer is formed on the Si surface. Third, boron atoms undergo solid-phase diffusion from the adsorbed layer into the bulk. The electrical characteristics of the PMOSFET in the short-channel region are superior to those of devices fabricated by conventional techniques.<>