  We have carried out extensive comparative studies of the structural and
transport properties of CaRuO$_3$ thin films grown under various oxygen
pressure. We find that the preferred orientation and surface roughness of the
films are strongly affected by the oxygen partial pressure during growth. This
in turn affects the electrical and magnetic properties of the films. Films
grown under high oxygen pressure have the least surface roughness and show
transport characteristics of a good metal down to the lowest temperature
measured. On the other hand, films grown under low oxygen pressures have high
degree of surface roughness and show signatures of ferromagnetism. We could
verify that the low frequency resistance fluctuations (noise) in these films
arise due to thermally activated fluctuations of local defects and that the
defect density matches with the level of disorder seen in the films through
structural characterizations.
