KLA-Tencor unveiled its sixth-generation fly-height tester for the data storage industry, the D6, to help enable hard disk drive (HDD) manufacturers meet the increasingly stringent manufacturing requirements for leading-edge storage devices. Incorporating a breakthrough phase interferometry technology that represents a departure from all previous fly-height metrology tools, the D6 provides a quantum leap in performance, with industry-leading precision and matching.
The D6 also offers, time reduced from hours to just minutes and total test time cut in half compared to previous fly-height systems.
"By 2010, an estimated 40 percent of all shipped HDDs will be used in consumer applications-up from about 14 percent in 2004," stated Tom Coughlin, president of Coughlin Associates, a data storage consulting firm. "This trend places greater demand on HDD manufacturers to not only produce affordable products with ever-increasing performance and storage capacity, but also to speed their ramp-up to volume production due to the shorter product lifecycles brought about by new consumer HDD applications. Significant investments in production capital spending must include spending on advanced metrology equipment to ensure that those production investments pay off in faster design, production yield improvement, and production ramps. With the ability to measure critical production parameters, a drive company will be able to get new products out early and reap the greatest profit."
As the data storage industry pushes toward higher storage capacities, the fly-height (the distance between the magnetic recording head and the disk) must shrink in order for the HDD to function properly. With the target for fly-height distance on the order of only a few nanometers for today's leading-edge HDDs, continuous fly-height production monitoring is critical to ensuring optimal performance and reliability of the disk drive.
Intensity-based interferometry tools have traditionally been used to make fly-height measurements, but have the inherent disadvantage that each recording head must be calibrated by retracting the head from the disk. At shorter fly-height distances, this process becomes increasingly difficult to perform without introducing measurement error. In addition, as fly-heights approach zero, the sensitivity of intensity-based interferometers diminishes.
At fly-height distances of 10 nm or less, these systems cannot meet the accuracy and robustness requirements for product design or production-line monitoring.
The D6 fly-height metrology system introduces a different measurement principle that enables measurements down to sub-3-nm fly-heights. It uses laser-based phase interferometer that eliminates the need for the mechanical retract that plagues previous-generation tools. In this technique, multiple signals are used to directly discern the differential phase of light reflected off the recording head surface without the need for calibrating the intensity envelope of the interference fringes -- thereby removing the need for retract calibration. As a result, all errors associated with the retract calibration process are eliminated, which improves measurement accuracy, repeatability and robustness.
The D6 has undergone an extensive beta evaluation and KLA-Tencor is currently accepting product orders. Shipping will begin in October 2005. An upgrade path is available for customers with existing D5 and D5xp fly-height systems.
KLA-Tencor :
http://www.kla-tencor.com
