High Temperature Ion Implantation Evaluation In Silicon & Germanium

High temperature ion implantation was investigated as a possible solution to reduce the thermal budget in doping processes. Pre-doped Si and Ge 200 mm wafers were used as substrates for implantation of (33)As and (5)B. Different heating methods were used. This includes the use of thermal transfer from a hot plate on the backside of the wafer or the thermal energy deposited by a high current density beam. An appropriate model was used to evaluate the wafer temperature when a direct measurement was not possible. We studied the efficiency of different configurations to maximise the thermal transfer to the wafer. The maximum temperature reached on the implanted substrate was calculated at 550 degrees C. Four-point resistivity measurements and spectroscopic ellipsometry were used to understand the influence of the in situ heating on the implanted materials properties. Interestingly, self-annealing resulting in activation and consequent re-crystallization is observed at a much lower temperature than what is usually required in standard post-implantation annealing.