Nitrogen-incorporated $SnO_2$ thin films were deposited by rf magnetron sputtering. Comparative structural, electrical and optical studies of thin films deposited by sputtering of the Sn metallic target and sputtering of the $SnO_2$ ceramic target were conducted. The $SnO_2$ thin films deposited by sputtering of the Sn metallic target had a higher electrical conductivity due to a higher carrier concentration than those by sputtering of the $SnO_2$ ceramic target. Structurally the $SnO_2$ thin films deposited by sputtering of the $SnO_2$ ceramic target had a better crystallinity and a larger grain size. This study confirmed that there were distinct and clear differences in electrical, structural, and optical characteristics between $SnO_2$ thin films deposited by reactive sputtering of the Sn metallic target and by direct sputtering of the $SnO_2$ ceramic target.