HEAVY-ION TIME-OF-FLIGHT ERDA OF HIGH-DOSE METAL IMPLANTED GERMANIUM

Heavy ion time-of-flight ERDA and conventional RBS have been used to s tudy the implantation profiles and oxygen uptake of Ge(100) implanted with high dose Ti and Cu ions from a MEVVA ion source. Cu implantation s were made at an incident ion dose of 3 x 10(17) atoms/cm(2), with Ge substrate temperatures at ambient 200 degrees C and 300 degrees C. A significant change in the Cu implantation profile was observed at 300 degrees C, consistent with that seen in thermal annealing studies. Ti implantations were made at 5 X 10(17) atoms/cm(2), with substrate temp eratures of 200 degrees C, 300 degrees C and 370 degrees C. Implantati on of Ti gave rise to a surface layer of average stoichiometry GeTi0.8 , which grew in thickness with implantation temperature. No significan t reaction with air or moisture was seen in the damaged Ge(100) implan tation surface region.