Jan. 29, 1999 (Electronic Engineering Times - CMP via COMTEX) -- Tokyo - The Rambus machine has hit full throttle, as chip, module and tester vendors announced efforts that may help ease a predicted shortage of Direct Rambus devices this year.
Most recently, Taiwan Semiconductor Manufacturing Corp. (TSMC) announced it would port the Rambus ASIC cell to its 0.25-micron process, a move that will allow chip companies using the foundry to incorporate the 1.6-Gbyte/second memory interface into their chip sets and into controllers for graphics or network switches. Chip vendors will be able to characterize the RAC megacell for their designs beginning in April.
UMC also has taken a Rambus license, and is in production with one Rambus-enabled device for a foundry customer, said marketing vice president Jim Ballingall. The TSMC and UMC announcements could hasten the move to Direct Rambus in PC graphics subsystems.
In Taiwan and Hong Kong last week, Intel and Rambus sponsored seminars on the module for PC OEMs. Though many small module makers lack a sufficient supply of RDRAMs, that will change soon, a Rambus spokesman said.
Eight DRAM makers are offering samples of 800-MHz parts, and the industry is still on schedule for the production of 64/72-Mbit devices, said Subodh Toprani, marketing vice president at Rambus, in Mountain View, Calif. He cited In-Stat figures predicting that Rambus will take 10 percent of the DRAM market this year, almost 40 percent next year and more than 50 percent in 2001.
One of the biggest expenses DRAM vendors will incur is the cost of new testers. Currently, the industry is in need of two types of testers for Rambus: IC testers used by chip suppliers and less-expensive testers that will be used by module makers.
"The IC testers can test for as many variables as you choose. You can change the timing and the voltage and get a complete picture of the operating range of the device," Toprani said. "The low-cost testers can measure the ac/dc timing but cannot handle a number of variables."
Until recently, Hewlett-Packard Co. was the only manufacturer selling full-fledged IC testers, but new high-speed DRAM testers are available from companies such as Advantest, Teradyne and Schlumberger. Toprani said many DRAM vendors are holding "bake-offs" to compare the equipment.
But tester companies are working to improve the handlers for microBGA
packages.
Tanisys Technology Inc. (Austin, Texas) is readying a Rambus in-line memory module tester that will go on sale soon. Tanisys marketing vice president Don McCord said the Darkhorse RIMM tester will provide the first affordable, full-speed tester to module makers that cannot afford to buy the multimillion-dollar chip testers. Offered in a "spread of configurations," the testers will sell for less than $250,000 to more than $1 million. Tanisys worked with Rambus Inc. to develop the tester.
The larger die size is another sticky issue for DRAM makers because it reduces wafer yields. Toprani said Rambus recently queried DRAM vendors and found that the die sizes range from 8 percent to 40 percent larger than PC-100 SDRAMs, with the average overhead being 13.5 percent. The size depends on each company's manufacturing process, though some of them learned that they didn't have to use extra-wide metal for the internal buses, Toprani said.
But Toprani said DRAM die sizes always vary widely among DRAM vendors. "At any point in time if you do this exercise you'll see it's two to one. But they all sell at the same price," he said.
All told, memory vendors will have to invest $7 million to $8 million for every million RDRAMs produced per month. So a DRAM maker that wants to output 5 million RDRAMs a month will have to spend about $40 million, Toprani said.
To help memory vendors defray costs, Intel Corp. has been making equity investments in some leading memory vendors. Last year it spent $500 mil-
lion to help Micron in its design and manufacturing of Direct RDRAMs. More recently it invested $100 million in Samsung Electronics for the same purpose.
One Japanese newspaper has reported that Intel is negotiating with NEC Corp. to close a similar deal. The companies later declined to comment. |
