HGST (formerly Hitachi Global Storage Technologies and now a Western Digital  company, NASDAQ: WDC) is leading the disk drive industry to the  forefront in nanolithography, long the exclusive purview of  semiconductor manufacturers, by creating and replicating minute features  that will allow the doubling of hard disk drive (HDD) density in future  disk drives.

HGST Labs announced today they have combined two innovative  nanotechnologies -- self-assembling molecules and nanoimprinting -- to  create large areas of dense patterns of magnetic islands only 10  billionths of a meter (10 nanometers) wide. These features are only  about 50 atoms wide and some 100,000 times thinner than a human hair.

“As creators of the original hard disk drive, we are proud to  continue our heritage of innovation with today’s nanotechnology  advance,” said Currie Munce, vice president, HGST Research. “The  emerging techniques of self-assembling molecules and nanoimprinting  utilized at the HGST Labs will have an enormous impact on nanoscale  manufacturing, enabling bit-patterned media to become a cost-effective  means of increasing data densities in magnetic hard disk drives before  the end of the decade.”

HGST’s discoveries in nanolithography overcome the increasing  challenges associated with photolithography. Long the preferred  technology among the semiconductor industry for achieving successively  smaller circuit features using traditional ever-shorter wavelengths of  light, improved optics, masks, photosensitive materials and clever  techniques, photolithography advancements have slowed as ultraviolet  light sources have become too complex and expensive.

HGST is becoming a leading player in nanolithography. Today’s  announcement represents a creative answer to the problems with  photolithography and has grown out of the storage industry’s unique  technical and strict cost targets. HGST nanolithography achievements  come at a critical juncture for storage drives as cloud computing,  social networking and mobility create an ever increasing amount of  content that must be stored, managed and accessed efficiently.

The Nanolithography Process

Tom Albrecht, HGST Fellow, spoke at this week’s SPIE Advanced  Lithography 2013 conference in San   Jose, CA., regarding HGST’s  nanolithography discoveries. He described the patent-pending work his  team did in partnership with Austin, Texas-based Molecular Imprints  Inc., to make dense patterns of magnetic islands in about 100,000  circular tracks required for disk drives.

Self-assembling molecules use hybrid polymers, called block  copolymers, composed of segments that repel each other. Coated as a thin   film on a properly prepared surface, the segments line up into perfect   rows.  The size of the polymer segments determines the row spacing.  After polymer patterns are created, a chip-industry process called line doubling makes the tiny features even smaller, creating two separate  lines where one existed before. The patterns are then converted into  templates for nanoimprinting, a precision stamping process that  transfers the nanometer-scale pattern onto a chip or disk substrate. A  key challenge proved to be preparing the original surface so the block  copolymers form their patterns in the radial and circular paths  necessary for rotating disk storage.  HGST is the first to combine  self-assembling molecules, line doubling and nanoimprinting to make  rectangular features as small as 10 nanometers in such a circular  arrangement.

Today’s announcement provides a roadmap for how to cost effectively  create the magnetic islands at densities much beyond today’s  capabilities. The bit density of HGST’s 10-nanometer pattern is double  that of today’s disk drives and lab tests show excellent initial  read/write and data retention. When extended to an entire disk, the  nanoimprinting process is expected to create more than a trillion  discrete magnetic islands.

“We made our ultra-small features without using any conventional  photolithography,” Albrecht said. “With the proper chemistry and surface   preparations, we believe this work is extendible to ever-smaller  dimensions.”

Because self-assembling molecules create repetitive patterns,  researchers expect they will be best suited to making bit-patterned  magnetic media for disk drives, uniformly spaced regions for computer  memories, various wiring contacts and other periodic features of other  types of semiconductor chips. Nanoimprinting and self assembling  molecules are also most easily introduced in defect-tolerant  applications such as disk drives or memory, even as the industry works  to perfect the technologies for more demanding applications.

Magnetic disk of the future This image above shows the dense patterns of magnetic islands made by HGST Labs using such emerging nanotechnologies as self-assembling molecules, line doubling and nanoimprinting.  Each dot can store a single bit of information.  This pattern has 1.2 trillion dots per square inch – twice the density of today’s disk drives. To make these islands, HGST Labs used the nanotechnoloiges to created dense patterns of even smaller 10-nanometer structures, each only about 50 atoms wide. HGST is first to combine self-assembling molecules, line doubling and nanoimprinting to make rectangular features as small as 10 nanometers in the radial and circular paths necessary for rotating disk storage. HGST expects bit-patterned media similar to this to become a cost-effective means of increasing data densities in magnetic hard disk drives before the end of the decade.