Detailed analysis and computationally efficient modeling of ultra-shallow as-implanted profiles obtained by low energy B, BF2 , and As ion implantation

With increasing levels of integration, future generations of integrated circuit technology will require extremely shallow dopant profiles. Ion implantation has long been used in semiconductor material processing and will be a vitally important technique for obtaining ultra-shallow dopant profiles. However, implant channeling for low energy ion implantation must be understood and minimized. We report the results of a detailed experimental analysis of 275 ultra-shallow boron, BF₂, and arsenic as-implanted profiles, and the development of an accurate and computationally efficient model for ultra-shallow B, BF₂, and As implants. The ultra-shallow dopant profiles have been modeled by using the Dual-Pearson approach, which employs a weighted sum of two Pearson functions to simulate the profiles. The computationally efficient model covers the following range of implant parameters: implant species B, BF₂, As; implant energies from 1 keV to 15 keV; any dose; tilt angles from 0° to 10°; all rotation angles (0°-360°). This experimental analysis is important for the development of scaled devices with ultra-shallow junctions, and the computationally efficient model will enable process simulators to predict ultra-shallow as-implanted profiles accurately