HIGH-DOSE GE-TEMPERATURE( IMPLANTATION INTO SILICON AT ELEVATED SUBSTRATE)

Germanium ions with a dose of 6 X 10(16) cm(-2) and at an energy of 16 0 keV were implanted into (100) Si wafers at room temperature (RT) and elevated substrate temperatures up to 500 degrees C. Post-implant ann ealing was performed at 950 degrees C for 1 h in N-2. Experimental res ults from XTEM micrographs show that the substrate temperature has a c onsiderable effect not only on the as-implanted, but also on the annea led behavior of Ge+-implanted Si. Higher substrate temperatures would be beneficial to improve the crystallinity of surface SiGe layer by th e elimination of the surface defects. The influence of different subst rate temperatures could be divided into two types. For implantation fr om RT to 100 degrees C, an amorphous layer still exists in as-implante d silicon, extended dislocations and a high density of surface defects remain in the recrystallized SiGe layer after annealing. For implanta tion above 200 degrees C up to 500 degrees C, where the amorphous laye r could not be generated due to dynamic annealing, a layer of about 15 0 nm thickness at the surface is nearly defect-free. Only extended dis locations, however large in size and low in density, exist at the dept h of 350 nm from surface. No EOR defects were observed in any of the s amples.