ALUMINUM CHEMICAL-VAPOR-DEPOSITION WITH NEW GAS-PHASE PRETREATMENT USING TETRAKISDIMETHYLAMINO-TITANIUM FOR ULTRALARGE-SCALE INTEGRATED-CIRCUIT METALLIZATION

A new gas phase pretreatment method was developed for blanket Al chemi cal vapor deposition (CVD) used in ultralarge-scale integration metall ization. This method uses a halogen-free Ti compound. The pretreatment process involves exposing substrates to a tetrakisdimethylamino-titan ium atmosphere before the Al CVD. This significantly lowers the deposi tion temperature of CVD using dimethylaluminum-hydride, and thus Al fi lms can be deposited on SiO2 even at 160 degrees C, where deposition w ould otherwise not occur. The deposited AZ films have superior surface morphology due to higher Al island density in the early growth stage. Using this technique, V-shaped trenches with an opening width of 0.4 mu m and a depth of 1.2 mu m are successfully filled with Al. (C) 1995 American Vacuum Society.