THERMAL EFFECT OF ION-IMPLANTATION WITH ULTRA-SHORT ION-BEAMS

Ion implantation with plasma guns operated in the detonation mode pres ents several differences from normally used low current ion implanter systems. The most important differences are the high power of the beam s generated with the plasma guns owing to their pulsed nature on one h and, and the plasma environment in which the target is immersed during the process of implantation on the other hand. Both effects were stud ied in this work. The temperature profiles and their evolutions during and after nitrogen implantation in pure titanium, stainless steel and copper were investigated by using the finite differences method. The calculation for nitrogen ion implantation (fluence of 10(13) cm-l and pulse time of 400 ns) in pure titanium, shows melting layers of 20 nm after the first 200 ns of implantation, with a fast cooling after the end of implantation. Thermal gradients of 1000 K mu m(-1) and a heatin g rate of 5 K ns(-1) were also observed. Optical spectroscopy observat ions (real time spectroscopy) of the implantation region show a highly activated nitrogen plasma. Both effects can be of extreme importance in several applications such as, for example, titanium nitriding becau se of an extra temperature assisted absorption by the getter effect.