Laser-assisted chemical vapor deposition of titanium nitride films

Abstract

We used a 193 nm ArF excimer laser to assist chemical vapor deposition of titanium nitride (TiN) films on Si (100) and SiO2. The source gases were tetrakis(dimethylamido)titanium (TDMAT) or tetrakis(diethylamido)titanium (TDEAT) mixed with ammonia. A correct stoichiometry was confirmed from Auger spectra. The laser helped to enhance TiN deposition rates at low temperatures (100 °C for TDMAT-NH3 and 200 °C for TDEAT-NH3). At higher temperatures the deposition rates decreased with an increasing laser energy density. Under irradiation the electrical resistivity of the TiN films was lowered. The laser-induced effect on electrical resistivity was particularly pronounced at low temperatures. A good conformality of the TiN films for contact holes with high aspect ratios was demonstrated.