Dynamic RAM Vendors Rethink Fab Plans For Europe

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April 02, 1998 (3:21 PM EST)

Dynamic RAM Vendors Rethink Fab Plans For Europe

Fujitsu may convert its U.K. dynamic RAM (DRAM) fabrication facility to a site that makes smart card integrated circuits under a plan being considered by the Tokyo-based company. Such a move could exploit exploit Fujitsu's recently developed ability to combine ferroelectric RAM (FRAM) with an 8-bit controller on a single die.

In separate announcements, Hitachi and Mitsubishi Electric have indicated they are planning changes for their operations in Germany.

The moves reflect a general reshuffling of fab strategies as major DRAM makers struggle to cope with DRAM price erosion.

Fujitsu has no plans for equipment upgrades that would enable 64-megabit production at its facility in Durham, England, a company spokeswoman said. That site now makes about 1 million 4-Mbit and 1.5 million 16-Mbit DRAM devices a month. Fujitsu's recent investments in DRAM production have gone instead to building a second fab in Gresham, Ore., where production for 64-Mbit and, later, 256-Mbit DRAM devices will take place.

Over the next few years, Fujitsu said it expects to switch production at Durham to microcontrollers. If demand for smart cards takes off in Europe, the spokeswoman said, Durham could become a smart card chip factory.

At the International Electron Devices Meeting in December 1997, Fujitsu engineers described work with Ramtron International on pairing CMOS logic with FRAM on chip. The engineers' IEDM paper described a chip that accommodates an 8-bit controller with 64 kilobits of FRAM using Fujitsu's 0.5-micron process technology. The prototype also packs 1 Kbit of SRAM and 8 Kbits of ROM.

Compared with the E2PROM used on most integrated circuit cards, FRAM based on the PZT material developed by Ramtron and its various partners is three orders of magnitude faster in write time, one order of magnitude lower in power consumption and five orders (100,000 times) more durable in terms of write cycles, Fujitsu said. Fujitsu and Ramtron developed materials that could be used with a 0.5-micron process technology, rather than the 1-micron process used at most FRAM-production sites.

In Europe, Fujitsu subsidiary ICL has developed technology that could put a variety of personal information, such as bank- and credit-account data and medical records, on a single card. "We don't want to replace many dumb cards with many smart cards," said a Fujitsu spokesman.

Although Durham conceivably could shift to smart card-chip production as early as 2000, the spokesman said the speed of the transition "all depends on the [market] volumes" for the cards.

Mitsubishi is also shuffling the responsibilities of its various overseas operations. The company operates a front- and back-end operation in Alsdorf, Germany, that employs 450 full-time workers and 150 part-timers, but it plans to move the test and assembly operations from Germany to Durham, N.C.

In January, Mitsubishi said it would close a front-end line at Durham that made 4-Mbit DRAM devices, while adding staff for microcontroller design projects. The latest plan is to shift all the Alsdorf assembly work to Durham -- making the North Carolina site a DRAM and memory-module production center for the U.S. market -- and increase 16-Mbit front-end production at Alsdorf from 1.5 million per month now to 2 million by year's end. Thirty jobs will be lost at Alsdorf.

Mitsubishi said it does not plan to equip Alsdorf for 64-Mbit DRAM production, however, and the German facility's long-term purpose may shift to microcontroller production.

By the end of the year, Mitsubishi said it expects to be making a total of 8 million 64-Mbit DRAMs per month. Japanese fabs will account for 5 million of those chips; the remainder will come from joint-venture fabs, which include a new facility in Japan that's operated with Seiko Epson and a Mitsubishi/UMAX/Kanematsu Trading Co. venture called Powerchip Semiconductor, in Hsinchu City, Taiwan.

One idea under consideration is to establish a design center at Alsdorf for embedded DRAM. If that works out, the German facility might eventually make the memory-with-logic chips as well.

Hitachi also has a German facility, located in Landshut. The fab handles both front- and back-end production tasks for 16-Mbit DRAM devices and produces a very small number of 64-Mbit devices. (Hitachi does not disclose production figures for its individual fabs.) A spokesman said Hitachi will eventually pull its DRAM manufacturing into two centers: the Naka Works, in Japan, and a joint-venture fab in Singapore owned by Hitachi, Nippon Steel, and the Singapore Economic Development Board. The latter has just started commercial production.

Hitachi may convert Landshut to a controller fab for telecommunications applications, the spokesman said.