IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Electronics Tuesday Sessions
       Session EL-TuP

Paper EL-TuP33
Diffusion Barrier Properties of Metallorganic Chemical Vapor Deposited Niobium Nitride Films Against Cu Metallization

Tuesday, October 30, 2001, 5:30 pm, Room 134/135

Session: Electronic Materials Poster Session
Presenter: C.W. Wu, National Tsing Hua University, Taiwan, ROC
Authors: C.W. Wu, National Tsing Hua University, Taiwan, ROC
W.C. Gau, National Tsing Hua University, Taiwan, ROC
J.C. Hu, National Tsing Hua University, Taiwan, ROC
T.C. Chang, National Sun Yat-Sen University, Taiwan, ROC
C.H. Chen, Namat Technology Co., LTD., Taiwan, ROC
C.J. Chu, Namat Technology Co., LTD., Taiwan, ROC
L.J. Chen, National Tsing Hua University, Taiwan, ROC
Correspondent: Click to Email
Amorphous NbN@sub x@ films were deposited by metallorganic chemical vapor deposited (MOCVD) using ethylimidotris(diethylamido)niobium(V) [Nb=NEt(NEt@sub 2@)@sub 3@] source with and without NH@sub 3@ at various temperatures. The diffusion barrier properties of NbN@sub x@ films for Cu metallization were investigated. In the MOCVD system, the precursor was introduced to reaction chamber by a bubbler with Ar as a carrier gas. Both deposition temperature and resistivity of the film was found to decrease drastically upon the addition of NH@sub 3@. The activation energy for the surface reaction was measured to be 0.82 eV in the temperature range of 500- 600°C and decreased to 0.23 eV by adding 20 sccm NH@sub 3@ in the temperature range of 300 - 400°C. The NbN@sub x@ films was found to be amorphous by X-ray diffractometry (XRD) and transmission electron microscopy (TEM). Concentration-depth analysis was carried out by Auger electron spectroscopy (AES). The concentration of C in films was reduced significantly and the concentration ratio of N to Nb was varied from 1.67 to 1.10 by using NH@sub 3@ as a reactant gas. From XRD and SEM observation, it was found that 50-nm-thick NbN@sub x@ film can effectively prevent penetrating of Cu in samples annealed at 550°C for 30 min. In samples deposited with 20 sccm NH@sub 3@, the barrier survived in samples annealed at 600°C for 30 min. The higher thermal stability of the films deposited with NH@sub 3@ is correlated to presence of N atoms in the NbN@sub x@ barrier films.