  Borocarbide superconductors, which are thought to be conventional BCS-type
superconductors, are not so conventional in several electronic Raman
properties. Anisotropic gap-like features and finite scattering strength below
the gap were observed for the $R$Ni$_2$B$_2$C ($R$ = Lu, Y) systems in our
previous study. The effects of Co-doping on the 2$\Delta$ gap-like features and
the finite scattering strength below and above the gap are studied in $R$ = Lu
(B = B$^{11}$) system. In superconducting states, Co-doping strongly suppresses
the 2$\Delta$ peak in both B$_{2g}$ and B$_{1g}$ symmetries. Raman
cross-section calculation which includes inelastic scattering shows a
relatively good fit to the features above the 2$\Delta$ peak, while it does not
fully account for the features below the peak.
