Optimizing Al Ion Implantation in Silicon Carbide Superjunction Devices: A Molecular Dynamics Approach

Achieving deep aluminum (Al) doping in silicon carbide (SiC) superjunction devices is crucial for the performance and reliability of these power electronic components. Despite the technological advances in ion implantation, there are still significant issues related to the precise control of doping profiles and junction depths, particularly in SiC materials. These challenges stem from the complex interactions between the implanted ions and the SiC crystal lattice, which can lead to unintended defect formation and uneven doping distributions. To better understand and overcome these issues, we employed molecular dynamics (MD) simulations to approximate the Al implantation process into SiC substrates. The use of MD simulations allowed us to model the atomic-scale interactions during the implantation process, providing insights that are difficult to obtain through experimental methods alone. The doping profiles of simulation results were agreed with experimentally observed data. This validation supports the accuracy of the simulation approach and its potential for predicting implantation outcomes under various conditions. In addition, the effects of implantation angle and the energy of the implanted ions on implantation profile were also investigated. As expected, increasing the implantation energy resulted in deeper penetration of the Al ions into the SiC substrate. However, this also led to a more uniform distribution in depth, which could potentially affect the precision of the doping process. The implanting Al ions into SiC substrates with a 20° off-axis angle resulted in a more favorable implantation depth and doping profile compared to other angles. This off-axis implantation strategy helps to increase the implantation depth and make the implantation distribution more uniform by channeling effects. Furthermore, our study examined the impact of implantation energy on the depth and distribution of Al dopants. These findings highlight the importance of optimizing both the implantation angle and energy to achieve the desired doping profiles in SiC superjunction devices.