History 2004: More About IBM’s 1TB Tape Project

At CeBIT 2003, IBM exhibited (under a glass display case) a tape cartridge, without the drive, that can hold up to 1TB of data.

What we saw looked something like a Magstar 3590-type cartridge, but no further information was provided.

In a recent white paper entitled “Six orders of magnitude in linear tape technology: the one-terabyte project,” six IBM researchers in Almaden, CA and Tucson, AZ, provide more details on exactly how that objective is to be reached, and the results of their demonstrations with respect to LTO-1 and -2.

This capacity, multiplied by 5 or 10, is the result of a combination of track pitch, linear density and tape length (see table below). The heads are 8-channel devices which span approximately one quarter of the half-inch tape width at a time. They comprise a side-by-side configuration of interleaved writer and reader transducers (8 each, spanned by 2 servo reader transducers) on each of 2 identical face-to-face modules. Writer transducers are 12-turn thin-film inductive elements. Reader transducers are conventional anisotropic magnetoresistive (AMR) sensors.

The media used for the demo was an experimental tape from FujiFilm with advanced metal particles with coercivity of more than 2,300Oe and a mean particle of 60nm.

The 1TB drive uses many components from an LTO unit, including reel-to-reel motors, servo electronics, head actuator and electronics, surface-control-guiding grooved rollers, and cartridge clutch and reels.

The key differences compared to current LTO are smaller track pitch (8.2μm) and the written-track width minus the reader width (2.8μm). Tracking improvements is also achieved by modifying the tape path. On the demo, IBM achieved, more specifically, 1,013GB of uncompressed capacity.

This article is an abstract of news published on issue 194 on March 2004 from the former paper version of Computer Data Storage Newsletter.