Nano-compact disks with 400 Gbit/in2 storage density fabricated using nanoimprint lithography and read with proximal probe

Nano-compact disks (Nano-CDs) with $\text{400\hspace{0.17em}}{\mathrm{Gbit/in}}^{\mathrm{2}}$ topographical bit density (nearly three orders of magnitude higher than commercial CDs) have been fabricated using nanoimprint lithography. The reading and wearing of such Nano-CDs have been studied using scanning proximal probe methods. Using a tapping mode, a Nano-CD was read 1000 times without any detectable degradation of the disk or the silicon probe tip. In accelerated wear tests with a contact mode, the damage threshold was found to be 19 μN. This indicates that in a tapping mode, both the Nano-CD and silicon probe tip should have a lifetime that is at least four orders of magnitude longer than that at the damage threshold.