| Although orders for DDR3 SDRAM chips have been few and limited to applications for extreme PCs and high-end desktops, major players in the memory sector are gearing up to supply the electronics industry when demand kicks in next year.
Micron Technology, Samsung Semiconductor, Hynix Semiconductor and Qimonda are preparing for the surge with 1-Gbit DDR3 SDRAMs, some of which are already in mass production. Micron has taken it one step further, unveiling a 2-Gbit DDR3 SDRAM earlier this month.
High-volume sales are not expected until mid-2009, when these suppliers say DDR3 will reach price parity with DDR2. DDR3 SDRAMs will make up less than 5 percent of DRAM shipments this year, according to Kevin Kilbuck, senior segment marketing manager for Micron Technology.
"One-Gbit is 100 percent of our DDR3 shipments, as we don't have 512-Mbit DDR3 and we haven't started 2-Gbit shipments yet," Kilbuck said. "One-Gbit is the right density to start with because it's the lowest cost per bit and the die size adder in percentage over DDR2 is much smaller for 1-Gbit than 512-Mbit."
DDR3 SDRAM is the DDR memory standard that is being developed as the successor to DDR2 SDRAM by the Jedec standards committee. The new functions in DDR3 build on the DDR2 SDRAM feature set but include logical improvements to increase system bandwidth (up to 1.6 Gbits/s per pin) and reduce power consumption.
An 8-bit prefetch architecture enables DDR3 DRAMs to achieve twice the data rate of DDR2 DRAMs, which use 4-bit prefetch, with the same DRAM core operating frequency. Providing improved system speeds (data rates up to 667 MHz/1333 MHz), lower power consumption (1.5 V vs. 1.8 V for DDR2) and larger memory densities than DDR2, DDR3 technology allows OEMs and ODMs to design systems with higher performance and larger overall memory capacities.
In addition to faster transfer rates and lower power consumption, DDR3 has improved pinout for better power and ground referencing, as well as enhanced write signaling via dynamic on-die termination and module layout to support higher speeds.
Vendors are looking at two key factors that they expect will accelerate DDR3 SDRAM demand: more memory controller and chip set support and lower cost.
"The current products that support DDR3 are only for high-end desktop PC platforms," Kilbuck said. "By the second half, memory controllers and chip sets that support DDR3 for mainstream desktops, notebooks and servers are expected to emerge."
Already, Intel is shipping P35 chip sets, which support new technologies such as a 1333-MHz system bus speed, next-generation 45-nm dual- and quad-core processors and DDR3 memory to deliver increased system bandwidth and improved performance.
According to Kevin Lee, vice president of memory marketing at Samsung Semiconductor (San Jose, Calif.), 1-Gbit DDR3 will continue to command a premium in 2008.
"Currently, demand for 1-Gbit DDR3 chips is limited to high-end systems," Lee said. "It is comparatively low, but increasing steadily."
Samsung has been using 80-nm process technology to produce its 1-Gbit DDR3 SDRAMs, which are now in mass production. Its product line supports speeds of 1066 and 1333 Mbits/s. Samsung will migrate to 68-nm process technology in the fourth quarter of this year, Lee said.
Micron Technology (Boise, Idaho) has started to sample the industry's first 2-Gbit DDR3 SDRAM for server, desktop and notebook applications. By using 2-Gbit components, Micron can produce 8-GB and 16-GB modules for servers and 4-GB modules for desktop and notebook PCs.
Micron's 78-nm, 2-Gbit DDR3 memory technology provides speeds of up to 1333 Mbits/s, enabling improved system and graphics performance. When operating at peak performance, DDR3 can transfer a 100,000-page document in approximately one second. And by reducing supply voltage from 1.8 V to 1.5 V, the 2-Gbit DDR3 component allows a 20 to 30 percent memory power savings compared with DDR2 technology.
Hynix Semiconductor plans to introduce 2-Gbit DDR3 parts in concert with customer demand, said Arun Kamat, vice president of marketing. It is currently sampling 1-Gbit DDR3 SDRAM but will move into volume production in the second quarter of 2008, depending on demand, he said. Products are manufactured using 66-nm process technology.