NEC Electronics and NEC Unveil New Breakthrough Technologies to Dramatically Reduce Power Consumption of System LSI Devices at 65 nm and Below

NEC Electronics Corporation and NEC Corporation today unveiled CMOS device and circuit technologies that reduce the power consumption of next-generation system LSI devices by several orders of magnitude. The new low-power technologies include a high-k transistor, body-bias-sensitive transistor configuration, and new circuits for optimizing supply and threshold voltage. Together, these innovations enable designers to dramatically reduce overall system-on-chip power consumption, to as much as 1/30^th the levels of conventional technologies.

"With the explosion of mobile devices and other applications with low power requirements, power consumption issues have moved to top of mind with today's system designers," said Kazu Yamada, associate vice president, Technology Foundation Development Operations Unit, NEC Electronics Corporation. "The rise in standby power at smaller technology nodes has made this issue especially challenging for designers of advanced LSI devices, but our new low power technologies represent a significant breakthrough, enabling what we are calling Ultimate Low Power. These advancements enable up to ten-fold improvement in battery life for an array of mobile applications, while still maximizing LSI performance."

Lowest LSTP Leakage with High-k Transistor and Body-bias-sensitive Configuration
Shrinking technology nodes have created serious power challenges for LSI device designers. Although the lower supply voltages (V_DD) of scaled-down LSI transistors reduces active power consumption, standby power consumption often increases due to higher leakage current as a result of reduced threshold voltage (V_TH) and gate-oxide levels. By the 65-nm technology node, leakage power consumption exceeds active power consumption for many devices, necessitating special design-flow procedures to balance performance with leakage power.

The combination of NEC Electronics and NEC's body-bias sensitive configuration with a high-k transistor effectively limits the three major sources of standby leakage: subthreshold leakage, gate-induced drain leakage (GIDL) and gate leakage. Although the body-bias configuration alone is ideal for reducing subthreshold leakage, it does not reduce gate leakage. Moreover, in low standby power (LSTP) mode, where channel concentration is high, body-bias may increase GIDL, rendering the technique counterproductive.

Introducing a carefully designed high-k transistor solves this problem and reduces gate leakage by approximately three orders of magnitude. Channel concentration is also reduced, making it possible to exert body-bias without increasing GIDL and thus widening the range to which the body-bias configuration can be applied. Using the technologies described above, NEC Electronics and NEC reduced standby leakage in 65nm LSTP transistors to 1.4p/0.32pA, the smallest value ever reported.

New Monitoring and Control Circuits Further Reduce Power Consumption
In addition to the high-k transistor and body-bias-sensitive configuration, NEC Electronics and NEC have also developed new circuit technologies that further enhance power consumption capabilities by addressing leakage current issues in both active and standby mode.

In active mode, the new circuits independently optimize V_DD and V_TH by monitoring circuit delay and comparing switching and leakage currents (I_sw, I_leak) to maintain the desired I_sw/I_leak current ratio. This marks the world's first circuit that monitors and controls these voltages independently. The net result is that active power consumption is minimized with excellent stability, while maintaining maximum LSI performance.

In standby mode, the circuits achieve the lowest possible standby power by comparing subthreshold leakage and GIDL, and modulating V_TH to maintain the point at which the two leakage currents are equivalent. In tests conducted by NEC Electronics and NEC, the control circuits were proven to detect the optimum point within 20 percent accuracy.

Ultimate Low Power Customizable for a Range of Applications
Using the three low power technologies (high-k transistor, body-bias-sensitive configuration and circuit technologies) independently or in combination, LSI designers can meet a wide range of power management goals that meet the requirements of various applications. For example, battery-powered products that maximize time in standby mode may realize the greatest benefit from the high-k transistors, whereas high-performance servers may realize the greatest power savings from the use of V_DD and body-bias-sensitive configuration. The monitoring and control circuits for adaptive V_DD/V_TH is effective across all ranges, enhancing power reduction capabilities in any application.

Availability
NEC Electronics and NEC will present these low power technologies at the 2005 Symposia on VLSI Technology and Circuits, held June 14-18 in Kyoto, Japan. The 65nm technologies are expected to be deployed in 2006. More information can be found at www.necel.com/process/en/lowpower_overview.html

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About NEC Corporation

NEC Corporation (NASDAQ: NIPNY) (FTSE: 6701q.l) is one of the world's leading providers of Internet, broadband network and enterprise business solutions dedicated to meeting the specialized needs of its diverse and global base of customers. Ranked as one of the world's top patent-producing companies, NEC delivers tailored solutions in the key fields of computer, networking and electron devices, by integrating its technical strengths in IT and Networks, and by providing advanced semiconductor solutions through NEC Electronics Corporation. The NEC Group employs more than 140,000 people worldwide and had net sales of 4,855 billion yen (approx. $45.4 billion) in the fiscal year ended March 2005.
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About NEC Electronics

NEC Electronics Corporation (TSE: 6723) specializes in semiconductor products encompassing advanced technology solutions for the high-end computing and broadband networking markets, system solutions for the mobile handsets, PC peripherals, automotive and digital consumer markets, and multi-market solutions for a wide range of customer applications. NEC Electronics Corporation has 26 subsidiaries worldwide including NEC Electronics America, Inc. (www.am.necel.com) and NEC Electronics (Europe) GmbH (www.eu.necel.com). For additional information about NEC Electronics worldwide, visit www.necel.com.