HGST (a Western Digital company), formerly Hitachi Storage, has achieved a breakthrough in nanolithography that will enable manufacturing hard disk drives with almost doubled data storage density in the foreseeable future. The breakthrough is achieved as a result of combining two nanotechnologies: self-assembling molecules and nanoimprinting. The new technique will allow for creating dense patterns of magnetic islands having a width equal to 10 billionths of a meter (10 nm).
This discovery by HGST will pave the way for meeting challenges in photolithography faced by the semiconductor industry. Various problems have been associated with photolithography due to the increase in complexity of ultraviolet light sources.
An HGST team has joined hands with Molecular Imprints Inc. (a Texas, Austin-based company) to develop this new technology for manufacturing hard-disk platters. They have worked together to create dense patterns of magnetic islands in approximately 100, 000 circular tracks.
The self-assembling molecules use a unique type of hybrid polymers (known as block copolymers) that comprise self-repelling segments. These segments form perfect rows after being coated on a properly prepared surface. The amount of spacing between each row depends on the size of row segments. After forming such a pattern, a chip-industry process (known as line doubling) is employed to make these patterns thinner and smaller. Once the line doubling process is completed, templates are created by these polymer patterns, which are then transferred onto a chip or disk substrate using nanoimprinting.
This innovation opens the door to achieve storage densities that are much higher than the existing benchmarks. This new technique is ideal for creating defect-tolerant applications, such as disk drives and memory. This work is still patent-pending and is yet to be implemented in commercially available drives.