SCIENCE

Behind the smart phone's continuing transformation into the quintessential multipurpose tool is the rise and diversification of microelectromechanical systems (MEMS), tiny machines that work the speakers, projectors, gyroscopes and other built-in gadgets that are inspiring a profusion of mobile applications. 

To date, the MEMS industry has earned the bulk of its global revenue—about $7 billion in 2010—from sales of accelerometers (for airbags) and other sensors for the automotive industry along with components for ink-jet printers, displays and hard-disk drives. But it's a sign of their rise in status that MEMS are getting singled out for recognition by both the semiconductor and electronics industries in their respective technology roadmaps. Industry roadmaps are forecasts of technology advances and processing improvements necessary to sustain progress in enhancing the performance of products while minimizing manufacturing costs. 

"Until only recently, MEMS devices have been viewed as distant cousins to computer chip technologies and consumer electronics," says Michael Gaitan, leader of the Enabling Devices Group at the National Institute of Standards and Technology (NIST). "But with the rapid growth of mobile computing devices like smart phones and tablets, MEMS devices are becoming the indispensable 'eyes and ears' of information technology products." 

Gaitan chaired the MEMS Technology Working Group that participated in drafting the 1,800-page technology roadmap just issued by the International Electronics Manufacturing Initiative (iNEMI). For the first time since 1994, when the consortium began producing biennnial roadmaps for the electronics industry, this year's installment contains a chapter devoted to understanding the evolution of MEMS technology and the technical challenges to achieving the manufacturing capabilities that will be required over the next 10 years. 

The working group has identified key challenges and gaps in device and reliability testing, wafer-level testing, modeling and simulation tools to support MEMS design, and standardization of assembly processes and packaging. 

"The MEMS industry faces a set of common technical challenges that may be solved more efficiently through cooperation," says Gaitan, who is currently working on assignment to the NIST Technology Innovation Program. "The cost of testing, for example, is rising. It now accounts for up to half of the total cost of making some MEMS devices. If this trend isn't reversed, sales and market growth will be at risk." 

Gaitan now chairs a newly launched MEMS Technology Working Group that will contribute to the next version of the International Technology Roadmap for Semiconductors (ITRS). This working group is focusing on MEMS devices integrated into today's smart phones, including accelerometers, gyroscopes and microphones, as well as emerging MEMS that will enable new uses of mobile information technologies. Projecting 15 years into the future, the working group is assessing requirements for device performance, design and simulation tools, packaging and integration, and testing. Their assessment will be included in the 2011 edition of the ITRS, which will be issued later this year. The ITRS has helped the semiconductor industry continue the decades-long trend of doubling the number of transistors on a computer chip about every two years.

The MEMS Industry Group, a trade association focused on advancing MEMS across global markets, has contributed to both roadmapping activities. 

NIST's participation in the iNEMI and ITRS efforts helps to guide its laboratory programs aimed at developing the measurement capabilities that industry will require to make current and next-generation technologies.