- Track Pitch
- Bit Width - Top and bottom
- Bit Length - Top and bottom
- Bit Angle - All sides
- Bit Height
Additionally, an AFM is very helpful for visualizing defects on the surface of masters and discs.
Figure 1: Three dimensional image of a stamper surface. The scan range is 10 × 10 microns and the maximum Z range is 192 nanometers.
Figure 2: 2-D image of the DVD stamper showing the alignment of bits. Any defects on the surface are readily identified in 2-D images.
Figure 3: Line profile of the stamper surface showing the measure of the bit width at the bottom, .535 µm, and at the top, .238 µm, of the bit. From similar profile analysis it other parameters such as the pitch and bit height are measured.