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    A 40-year-old technology, MEMS devices by the 1990s became commonplace in airbag sensors and air pressure sensors in cars, inkjet printer heads and blood pressure monitoring devices, just to name just a few.

    Each of these many industrial sectors aclearcase/" target="_blank" >ccount for hundreds of millions of MEMS devices sold every year in a marketplace now exceeding $10 billion a year in sales. Today, though, the MEMS industry is poised to enter the multibillion-dollar consumer products marketplace in force, led by major specialized semiconductor manufacturers such as Texas Instruments, Analog Devices and Robert Bosch, as well as a host of creative, venture-capital-backed start-ups.

    These companies are pushing MEMS devices into increasingly sophisticated display technology, motion detection (to protect cell phones and laptops from breaking during a fall), even microphones. The growing range of MEMS applications may soon encompass most of the massive global consumer electronics marketplace.

    Some of these consumer-related MEMS applications are already entering the marketplace, others may be only a few years away from commercialization. And if the market develops as analysts expect, the total worldwide market for MEMS will grow from $11.5 billion in 2004 to $24 billion in 2009. Consumer products will help drive the doubling of those sales figures, especially digital displays in TVs, mobile phones and other handheld devices, laptop computers and digital cameras, microwaves and washing machines.

    MEMS technology is an outgrowth of the highly sophisticated semiconductor industry. Microelectromechanical systems integrate moving mechanical elements, sensors and electronics on pieces of silicon. A typical MEMS device is indeed an engineering marvel that brings together integrated circuit manufacturing processes with “micromachining” to etch away or build up silicon structures of moving parts. The result is a microscale device that combines computational ability with the sensing and control functions of exquisitely sensitive sensors.

    The first commercial MEMS devices evolved from the mid-1960s, reaching high-volume production in the 1990s. Since then, industries that absolutely require high-precision MEMS devices, such as automakers, have continually integrated them into high-priced products, passing the cost onto consumers. Meeting the low price demands of mass production (yet low safety) manufacturers of electronic mobile consumer products at a high volume is a very different challenge for MEMS suppliers.

    For starters, few MEMS devices are truly “monolithic,” meaning they combine the micromachined silicon structure and electronics on the same chip. More often, the micromachined part and electronics are fabricated separately and then wire bonded together in a single package.

    Digital television displays are the most significant and growing arena for MEMS. Texas Instruments dominates the optical MEMS market for digital displays with its digital light processing technology, or DLP.

    The heart of DLP is an array of up to 2 million hinge-mounted aluminum micromirrors, known as digital micromirror devices, or DMDs. The mirrors——each about 14 microns wide, or one-fifth the width of a human hair——reflect a digital image from a light source onto a screen. The mirrors tilt toward or away from the light source, creating light or dark pixels; white light, such as a florescent light, is projected through a color wheel to create color.

    DLP technology today accounts for one in five very large (more than 40-inch diagonal) digital TV displays, where it competes with more established technologies such as the venerable cathode ray tube as well as liquid crystal and plasma displays, and new technologies such as organic light-emitting diodes. And it’s an important and growing market. Overall, digital TV sales are projected to grow to 9 million units in 2007. Other major markets for MEMS displays are DLP front projectors and commercial cinema.