  K x-ray emission from copper plasmas produced by 100 fs, 806 nm laser pulses
at intensities in the range of 10^15-10^16 W cm^-2 is studied with respect to
input laser polarization and target surface conditions. We demonstrate that
even moderate surface roughness enhances the characteristic x-ray yield by as
much as 70 %. We further show that surface roughness of the targets overrides
the effect of polarization state in light coupling to the plasma.
