Implant Damage Studies with Different Implant Temperature by Spot and Ribbon Beam

Abstract

Wafer temperature during implant has a dominate effect on the amorphous layer thickness and post anneal residual defects which can result in difference in device performance and difficulties in tool matching between different implant systems, namely batch type vs. single wafer implanter and spot beam vs. ribbon beam system. Although the implant temperature set point can be well defined and controlled, the instantaneous temperature on wafer during implant is quite complicated interactions among beam shape, dose rate, duty cycle and cooling system to the behavior of defect generation and dynamic annealing. A batch system, iStar, and a single wafer system, iPulsar, which delivers both spot beam and ribbon beam with cold implant capability were used to study the effect of implant temperature to the post anneal residual defects by BF 2 15keV 3×10 15 cm -2 implant after 850°C/ 30s anneal. Measurements from Rs, SIMS, plane view TEM are compared and analyzed. The results by ribbon beam and spot beam are also compared.