IBM copper chip due for Macs

IBM's chance for chip greatness will come later this summer with the release of its first copper-based PowerPC microprocessors, intended for Macs.

Michael Kanellos Staff Writer, CNET News.com
Michael Kanellos is editor at large at CNET News.com, where he covers hardware, research and development, start-ups and the tech industry overseas.
Michael Kanellos
3 min read
IBM's chance for chip greatness will come later this summer with the release of its first copper-based PowerPC microprocessors, intended for Apple Computer's Macintosh systems.

IBM's microprocessor operations often go unnoticed due to the large shadow cast by chip behemoth Intel, but the release of the copper processor will highlight Big Blue's long-established manufacturing prowess as well as its efforts to take the lead in one of the most critical new chip technologies for the next decade.

IBM's first copper processors, which are code-named Lone Star and use copper wire rather than aluminum to connect transistors, will run at speeds of 400 MHz and lower, according to sources close to IBM. Versions running at 333 MHz and 366 MHz are expected to be available at the same time, which is probably not later than September.

The initial products will be targeted at the Macintosh market and found in Apple computers and Mac upgrade cards. Samples have already been shipped to IBM partners.

While the first versions of the chip will only slightly boost performance over current aluminum microprocessors, future copper processors are expected to reach speeds up to 1 GHz (1,000 MHz).

Sources at IBM have said that copper chips will be commercially available in the summer, but various analysts have said that the debut may be more like a trial release. That is, chips will be available, but perhaps not too many of them.

Beyond the shift in metals, IBM will use a 0.18-micron manufacturing process to produce these chips, a more advanced technique than Intel currently uses on its production lines.

"That's not surprising," said Dean McCarron, principal analyst at Mercury Research. "They [IBM] tend to have the technology leadership."

1998 has been a busy one for IBM Microelectronics. Since the beginning of the year, IBM has signed manufacturing deals with several Intel clone chip vendors, in what many have called an effort to stake out a stronger presence in that market. (Its deal with AMD, however, was recently postponed.)

IBM has also led the charge toward using copper, which conducts better than aluminum and is expected to lead to faster, more efficient microprocessors. The PowerPC chips will be followed by copper-based, custom-made ASICs (applications specific intergrated circuit) chips. IBM is working with approximately ten other companies to develop ASICs, according to an IBM spokesman.

In all likelihood, copper chips based around the Intel architecture will follow. To IBM, the 0.18-micron process and copper technology are synonymous, said the spokesman. IBM has no current plans to make aluminum chips on the 0.18-micron process technology; however, since most chip vendors plan to move their x86 chips from the 0.25 to the 0.18 micron processes next year, copper chips based around the Intel architecture will surely come.

Yesterday, AMD and Motorola announced they would collaborate on making copper chips. But IBM maintains that it holds a substantial lead in this field.

"We believe we have a six-month to year lead on everyone," said the IBM spokesman.

The shift to copper will only result in an incremental improvement in the 0.18-micron generation of chips, according to Nathan Brookwood, semiconductor analyst for Dataquest. Most of the improvements the physical properties of copper can bring will come with the subsequent 0.13-micron manufacturing process, as still smaller transistors will better synchronize with the higher speed interconnections.

"You really need 0.13.," he said. "It's like city traffic with traffic lights on every corner. With 0.18, you get to the traffic light a lot faster, but you spend a lot more time waiting at the light. When you get to 0.13, the traffic lights start getting shorter."

McCarron, among others, agreed that the first generation of copper chips at 0.18 microns functions more as a starting place than a point for comparing performance. He added that copper will add performance as processors approach and exceed 600 MHz.

Intel for the moment is not scrambling toward copper, according to Linley Gwennap, editor in chief of The Microprocessor Report. While Intel is undoubtedly performing research on copper interconnect circuitry, the company appears to be concentrating more on low capacitance "di-electric" technology, which improves the performance of the materials surrounding the circuits, rather than the circuits themselves. Essentially, capacitance is reduced between the layers in a chip.