Title :
CVD and PVD transition metal nitrides as diffusion barriers for Cu metallization
Author_Institution :
R&D, Semicond.. Manuf. Co., Hsinchu, Taiwan
Abstract :
The physical and electrical properties of transitional metal nitrides: tantalum nitride, tungsten nitride and molybdenum nitride thin films deposited by thermal decomposition of metalorganic precursors of TBTDET, BTBTW, and BDBTM have been investigated. The films have an excellent step coverage over high aspect-ratio contact holes as well as low carbon concentration. Strong metal to nitrogen double bonds in the precursors preserved the cubic phase of the films during the pyrolysis process and subsequently yielded low-resistivity films. X-ray diffraction (XRD) and wavelength dispersive spectroscopy (WDS) results indicated that the as-deposited films have face centered cubic (fcc) phase polycrystalline structure. Diffusion barrier properties of these films for copper metallization were studied by SEM, TEM, diode leakage current measurement and secondary ion mass spectroscopy (SIMS) analysis. The metal nitride thin films deposited by physical-vapor-deposition (PVD) were compared to CVD films as well
Keywords :
CVD coatings; X-ray chemical analysis; dielectric thin films; diffusion barriers; electrical resistivity; integrated circuit metallisation; leakage currents; molybdenum compounds; scanning electron microscopy; secondary ion mass spectra; tantalum compounds; transmission electron microscopy; tungsten compounds; BDBTM; BTBTW; CVD; Cu metallization; Cu-MoN-Si; Cu-TaN-Si; Cu-WN-Si; PVD; SEM; SIMS; TBTDET; TEM; X-ray diffraction; carbon concentration; cubic phase; diffusion barriers; diode leakage current; double bonds; high aspect-ratio contact holes; low-resistivity films; metalorganic precursors; polycrystalline structure; pyrolysis; thermal decomposition; thin films; transition metal nitrides; wavelength dispersive spectroscopy; Atherosclerosis; Contacts; Copper; Dispersion; Nitrogen; Sputtering; Thermal decomposition; Tungsten; X-ray diffraction; X-ray scattering;
Conference_Titel :
Solid-State and Integrated Circuit Technology, 1998. Proceedings. 1998 5th International Conference on
Conference_Location :
Beijing
Print_ISBN :
0-7803-4306-9
DOI :
10.1109/ICSICT.1998.785865
