The upper figures shows traces of polishing called a texture on the surface of a hard disk. The lower figures shows a laser texture also on the surface of a hard disk. The SFT (Surface Tracer) allows you to observe

3-dimensional shape accurately in the atmosphere without evaporation or non-destructive method. Any image data can be processed using a computer. In addition to the observed images as shown in the left figures therefore, the calculation of roughness, histogram or bearing ratio as shown in the right figures is also available with a ease.

The SFT measures textures, laser bumps, pits, film thickness and steps to provide data for the manufacturing control or process development of disks and wafers which is unavailable from a conventional tracer type surface roughness tester or electron microscope.

In view of the current tendency of disk media to higher density, the serviceability of the SFT, which serves as an advantage tool for micro-roughness measurements, will surely increase in the future.