Open AccessBarrier/Cu contact resistivity
Author(s) -
J.S. Reid,
Nicolet,
Angyal,
D. A. Lilienfeld,
Yosi ShachamDiamand,
Paul Martin Smith
Publication year - 1995
Language(s) - English
Resource type - Reports
DOI - 10.2172/119996
Subject(s) - electrical resistivity and conductivity , materials science , tin , barrier layer , scattering , amorphous solid , analytical chemistry (journal) , contact resistance , impurity , condensed matter physics , mineralogy , optics , crystallography , chemistry , nanotechnology , physics , metallurgy , layer (electronics) , quantum mechanics , chromatography , organic chemistry
The specific contact resistivity of Cu with ({alpha} + {beta})-Ta, TiN, {alpha}-W, and amorphous-Ta{sub 36}Si{sub 14}N{sub 50} barrier films is measured using a novel four-point-probe approach. Geometrically, the test structures consist of colinear sets of W-plugs to act as current and voltage probes that contact the bottom of a planar Cu/barrier/Cu stack. Underlying Al interconnects link the plugs to the current source and voltmeter. The center-to-center distance of the probes ranges from 3 to 200 {micro}m. Using a relation developed by Vu et al., a contact resistivity of roughly 7 {times} 10{sup {minus}9} {Omega} cm{sup 2} is obtained for all tested barrier/Cu combinations. By reflective-mode small-angle X-ray scattering, the similarity in contact resistivity among the barrier films may be related to interfacial impurities absorbed from the deposition process