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 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.