Characterization of titanium oxynitride films deposited by low pressure chemical vapor deposition using amide Ti precursor

In this study, we investigate the use of an amide-based Ti-containing precursor, namely tetrakis(diethylamido)titanium (TDEAT), for TiNxOy film deposition at low temperature. Traditionally, alkoxide-based Ti-containing precursor, such as titanium tetra-isopropoxide (TTIP), along with NH3 is used for titanium oxynitride (TiNxOy) film deposition. When TTIP is used, at low temperatures it is difficult to form TiNxOy films with high N/O ratios. In this study, by using TDEAT, TiNxOy films are deposited on H-passivated Si (100) substrates in a cold wall reactor at 300 °C and 106 Pa. Rutherford backscattering spectroscopy analysis shows nitrogen incorporation in the TiNxOy films to be as high as 28 at.%. X-ray photoelectron spectroscopy analysis of as-deposited films confirms the formation of. TiNxOy, while Fourier transform infrared and Raman spectra indicate that the films have amorphous structure. Moreover, there is no detectable bulk carbon impurity and no SiO2 formation at the TiNxOy/Si interface. Upon annealing the as-deposited films in air at 750 °C for 30 min, they oxidize to TiO2 and crystallize to form a rutile structure with a small amount of anatase phase. Based on these results, TDEAT appears to be a promising precursor for both TiNxOy and TiO2 film deposition.