HMT Technology Corporation Announces Advanced Media Capable of Supporting 11.3 Gbit/in2 Areal Density.

FREMONT, Calif.--(BUSINESS WIRE)--July 16, 1998--HMT Technology Corp. (NASDAQ/NM:HMTT) announced today the demonstration of a recording density of 11.3 Gbit/in2 using high areal density Giant MR (GMR) recording heads produced by ReadRite Corp. (NASDAQ:RDRT) and HMT patented, ultra low noise, low glide disks. This areal density could support in excess of 15 GB on a 3 1/2" diameter platter. This achievement is significant in two ways. It represents one of the highest areal densities achieved in the industry and actually the highest storage capacity attained using an integrated read/write head as opposed to separate heads to write and to read the data. Also, it is the first leading edge density announcement, utilizing GMR heads, from a collaboration between two independent component suppliers, making this extremely high performance head media combination available to non-vertically integrated disk drive manufacturers.

The Giant MR heads used at ReadRite for this demonstration were produced in ReadRite's Fremont, CA production facility. The disks provided by HMT have Mrt around 0.5 memu and coercivity of about 2900 Oe and were produced on HMT standard manufacturing equipment using a recently developed compound underlayer/magnetic alloy layer combination deposited on an ultra low glide highly polished NiP/Aluminum disk substrate. Linear densities of 372,000 bits-per-inch, which is the highest linear density reported in any recording demonstration, and track densities of over 30,000 tracks-per-inch were achieved with an on-track error rate better than one part in a billion. The demonstration was done at 170Mb/s data rate.

Dr. Michael A. Russak, Vice President of Research and Development at HMT commented, "We are pleased with this achievement and the fact that both HMT and ReadRite Corporations, working together, are capable of producing compatible leading edge technology components for our customers' future products."

The statements in this news release may contain forward-looking statements that involve risks and uncertainties that could cause actual results to differ from predicted results. Further information on factors that could affect the company's results is detailed in the company's reports on Form 10-K for the year ended March 31, 1998 and Form 10-Q for the period ended December 31, 1997, as filed with the Securities and Exchange Commission. The company undertakes no obligation to publicly release the result of any revisions to these forward-looking statements.

HMT Technology Corporation independently designs, develops, manufactures and markets high-performance thin-film disks. The company's products are used in high-capacity hard disk drives for a variety of high-end applications, including personal computers, network servers and workstations, and in certain removable hard disk drive applications. The disks currently being shipped by HMT primarily have coercivity levels of 2000 to 2700 Oersted, a measure of storage capacity, and glide heights of 1.5 to 0.8 microinches. The company's shares are traded on the Nasdaq National Market under the symbol HMTT. Additional information may be obtained by visiting HMT's website at http://www.hmtt.com, or by contacting the company directly.

    CONTACT: HMT Technology Corporation
              Peter Norris, 510/490-3100
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              Deborah Stapleton, 650/470-0200