IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Wednesday Sessions
       Session DI-WeM

Paper DI-WeM8
Characteristics of Tungsten Nitride Atomic Layer Deposition

Wednesday, October 31, 2001, 10:40 am, Room 130

Session: Atomic Layer Deposition for Silicon Devices
Presenter: H.S. Sim, Korea Institute of Science and Technology
Authors: H.S. Sim, Korea Institute of Science and Technology
Y.T. Kim, Korea Institute of Science and Technology
H. Jeon, Hanyang University, Korea
Correspondent: Click to Email
Atomic layer deposition method for binary or ternary metal nitride film such as TiN, W-N, TaN, and TiSiN has been proposed to get a nano-scale diffusion barrier thin film. In this work, we have deposited W-N atomic layer with multiple cycles of introducing WF@sub 6@, N@sub 2@, NH@sub 3@, and N@sub 2@ gases in order. A cycle time was varied from 1 - 5 sec for an atomic layer. Deposition rate per cycle, crystal structure, and atomic lattice image for interface of W-N and Si were determined with high resolution transmission electron microscopy (HR-TEM). We have investigated atomic deposition windows at temperatures between 250 - 450 °C. As a result, deposition rate per cycle was nearly the same and the resistivity of as deposited W-N was about 100 ~ 300 µ@OHM@-cm. The diffusion barrier performance of both as-deposited and post-annealed W-N films at temperatures between 500 and 700 °C were investigated in the view points of Cu diffusion mechanisms through surface and grain boundary. As a nano scale diffusion barrier for Cu interconnect, we have investigated correlations between Cu diffusion and texture, composition change and crystalline structures of W-N atomic layer during post-annealing with medium energy ion spectrometry (MEIS) as well as HR-TEM.