Defect printability and sensitivity of reticle inspection systems were studied for 0.18 micrometer-rule devices. For our evaluation, an OPC test reticle was designed, and fabricated with E-beam and dry-etching. Base patterns are 0.18 micrometer-rule memory cells. Serif length is 0.3 micrometer and step is 0.1 micrometer (on reticle). The programmed defects have varieties of types, locations, and sizes. For the defect printability test, we used a 4 X KrF scanner (NA equals 0.6, (sigma) equals 0.75), and resist image was measured by CD-SEM. The defects which cause more than plus or minus 5% CD error were defined as 'printable' defects. It was cleared that very small defects can be printed on the wafer. For instance, 50 nm side placement defects were printed. Several inspection systems were evaluated and compared with our printability specification. From our result, there were no systems which have better performance than our specification. However, some latest systems were very close to our specification.