Abstract: A method of detecting mask defects in which a reference substrate is patterned by the mask immediately after manufacture of the mask is disclosed. The reference substrate is stored in clean conditions while IC manufacture takes place. When a mask defect is suspected, a resist coated substrate, the test substrate, is patterned by exposure of the mask. The patterns on the reference substrate and the test substrate are compared to determine if there is a mask defect. The location of the mask defect can be found by scanning smaller areas of the patterns.

Abstract: A method of detecting mask defects in which a reference substrate is patterned by the mask immediately after manufacture of the mask is disclosed. The reference substrate is stored in clean conditions while IC manufacture takes place. When a mask defect is suspected, a resist coated substrate, the test substrate, is patterned by exposure of the mask. The patterns on the reference substrate and the test substrate are compared to determine if there is a mask defect. The location of the mask defect can be found by scanning smaller areas of the patterns.

Abstract: Magneto-optical recording medium comprising a substrate and a recording multilayer, the recording multilayer having perpendicular magnetic anisotropy and comprising layers of a first kind, which are principally comprised of Co, alternately stacked with layers of a second kind, which comprise metal other than Co, successive layers of the first kind being ferromagnetically coupled across interposed layers of the second kind, whereby at least one of the layers of the second kind which is bounded on both sides by layers of the first kind is substituted by a coupling structure comprising at least one layer of antiferromagnetic coupling material, across which coupling structure the immediately adjacent layers of the first kind are antiferromagnetically coupled. Such a magneto-optical recording medium is suitable for super-resolution data storage and retrieval, and for a direct overwrite procedure which does not involve magnetic field modulation.