RAPID THERMAL-PROCESS FOR ENHANCEMENT OF COLLIMATED TITANIUM NITRIDE BARRIERS

A rapid thermal processing (RTP) method to improve the barrier propert ies of collimated titanium nitride (TiN) was studied. The RTP for the collimated TiN shows a significantly improved diffusion barrier proper ty with reduced electrical contact resistance compared to a convention al furnace annealing process. Aluminum planarization was performed on subhalf micron contacts with various TiN barrier processes to examine electrical properties. When RTP is used, collimated TiN of much smalle r thickness than the furnace-annealed collimated TiN shows reliable el ectrical contact properties without junction leakage failure at subhal f micron contacts. When simultaneous in situ RTP for Ti silicidation a nd stuffing is performed, we obtain greatly improved p(+) contact resi stance. This is due to the phase transformation of Ti-Si amorphous lay er to crystalline TiSi2 at Si/barrier interface, as observed by cross- sectional transmission electron microscope.