Perfection is achieved, not when there is nothing to add,
and when there is nothing to remove.

Antoine de Saint-exupéry

Стеклянные пластины - основа жестких дисков следующего поколения, объемом в 20 ТБ и больше

12 Sep 2017


Anyone who deals with computers for a long time, remembers a time when disk drives were measured in megabytes, and that was quite enough for normal operation. Some time after this size of hard disks began to be measured in gigabytes, and the current hard drives are measured already in the units and tens of terabytes. Unfortunately, the possibilities of currently used technologies of magnetic recording is almost exhausted and further increase the volume of storage devices, we need a completely new technology. One such innovative technology was developed by the specialists of the Japanese company Hoya, and the basis of this technology is the plate of special glass, the use of which will allow hard disk drives the next generation to step over the mark of 20 terabytes.

Currently, glass plates are used mainly in 2.5-inch hard drives for laptops and other portable computers. In a typical 3.5-inch hard drives used plates made of aluminum, which is less durable than specialized glass. Glass plates, due to their strength, can be made thinner than aluminum, allowing more space in the volume of the casing of the hard disk, which can be used for the deployment of additional plates or nodes that implement the new technology high-density magnetic recording.

Currently, the company Hoya was able to demonstrate prototypes of 3.5-inch hard drives with glass plates of thickness 0.5 and 0.381 millimeter. One of the biggest current hard disk drives is Western Digital, with eight plates and a capacity of 12 terabytes. If this disk place 12 glass plates and to use the traditional recording method (shingled magnetic recording, SMR), its capacity will be increased to 20 terabytes.

In addition to the smaller thickness and higher strength, a glass plate is much better suited for the technology of thermal magnetic recording (heat assisted magnetic recording, HAMR), which is expected very soon, will be the main technology used in hard drives. In this technology, the recording of bits of information produced in a tiny region of the surface of the platters, which is pre-heated to a high temperature using laser light.

A glass plate without loss can handle spot heating the surface to a temperature of 700 degrees Celsius, while as the temperature limit for aluminium is of the order of 200-300 degrees Celsius. Due to this, the recording density on the glass plate can be increased to 1.5 - 2.5 terabits per square inch that will help future hard drives "step" far beyond the 20-terabyte mark.