The MEMS industry saw healthy 10 percent growth in 2012, and can expect continued strong expansion for the foreseeable future, projects Yole Developpement. The firm sees continuing 12-13 percent compound annual growth -- doubling the sector’s revenues to $22 billion by 2018. But that stable growth masks plenty of change from sector to sector within the diverse MEMS industry, as the high-volume consumer business drives fast innovation cycles. Meanwhile, the market for ink jet heads is declining, but mobile markets look likely to starting to adopt new MEMS timing devices, RF devices, and even environmental sensors. Notably, the diverse higher value, lower volume, industrial market (which ranges from telecommunications to aerospace and defense) will also match the consumer market’s ~12 percent growth rates, and medical MEMS markets will grow much faster at around 22 percent.
“Soaring smart phone demand for inertial sensors and MEMS microphones has driven much of the recent growth, but the discrete inertial sensor business is rapidly maturing and already leveling off,” notes Yole founder and CEO Jean Christophe Eloy, who will speak at the upcoming SEMICON West (www.semiconwest.org). “Demand is moving now to combination sensors instead, which will see 43 percent growth over the period.”
Yole projects this MEMS market growth will drive ~5 percent growth in equipment sales to >$510 million by 2018. But demand will likely become more cyclical, as the maturing sector becomes more closely tied in to the general electronics market, with double digit growth for the next few years followed by a slowdown until demand again catches up with installed capacity.
The major issue for MEMS manufacturing is driving down device size to reduce costs, as the integration of MEMS into multi-sensor combination packages steps up demand for miniaturization again. That means growing adoption of package-level die stacking approaches like TSVs. On the MEMS structure side, however, further major reductions in device size will probably need to come from some alternative technology to replace capacitive sensing. “We’re seeing more and more interest in PZT thin film for MEMS,” says Eloy.
Mature micro-mirror array business finds applications beyond projection by opening up DLP platform
Ways to open up MEMS design to more creative minds will also be key to future growth. It turns out that micro-mirror arrays might be a platform for many more applications beyond projection, as users keep finding more uses for the Texas Instruments DLP chip. “Engineers have been trying to rip apart projectors to use the DLP for their new ideas, so we formed a product line around this interest,” says Gina Park, Texas Instruments product line manager. The company has introduced a series of development platforms to make it easy for a wide range of users to create new applications for the device.
Even before the development kit was available, some people had developed products on their own. One doctor in Europe created a phototherapy tool for psoriasis patients that protected their healthy skin from damaging UV rays by controlling projection of the UV treatment light only onto the infected areas.
Most promising new markets so far appear to be scanners for 3D machine vision, 3D printing, and medical imaging, while portable spectroscopy could also have potential. DLP devices could offer a simpler and lower cost solution to fast and precise industrial inspection and measurement, compared to competing solutions of multiple cameras or laser scanning systems. DLP-based systems are being used in 3D printing of precision polymer molds for hearing aids and detailed jewelry. Medical applications include 3D dental scanning to map a tooth, then 3D printing out the mold for making a crown that fits precisely. Other wave lengths can image the vascular system within the body.
While many of these are niche markets, they do all use the standard mirror devices. Customization may involve things like optimizing the window for UV transmission and enhancing the control software.
Open technology platforms could also grow market
Other MEMS makers see open manufacturing platforms as a way to open MEMS design to more players. Major device makers InvenSense and STMicroelectronics have recently made their inertial sensor platform technologies available on multi-project wafers for development. Foundry X-FAB is starting production for a first lead customer of a product based on its open platform for 3-axis accelerometers and gyroscopes. Customers interested in the platform are typically chip makers currently buying MEMS sensors outside but who see advantage in moving more control in house to use with their own differentiating ASIC or SiP technology, reports Iain Rutherford, Business Line Manager for MEMS. “This opens up the sensor fusion market for a lot of people who have interesting applications but might not want to get into MEMS themselves,” he says.
More users develop more innovative applications
One prime example of an innovative path forward for getting more out of inertial sensors is BodyMedia’s work on combining the motion data with measures of heat and electrical signals from the body for monitoring health conditions. Currently, the company’s armband combines motion data from an accelerometer with measures of heat dissipation from an array of temperature sensors, and of galvanic skin response from the conductivity between two electrodes as the body sweats from heat or exercise. These measures allow much more accurate calculation of calories burned than with just the accelerometer, earning the device a following among those trying to lose weight. Coming next, says CTO Ivo Stivoric, are sensors to track heart beats and fluid volumes from electrodes in the arm band, then use the motion sensor data help filter out the muscle noise to improve the signal. “The electrocardiogram (ECG) signal from the armband is currently mapping to within ~5 percent of the data from the usual electrodes across the chest in clinical trials,” he reports. Measuring transmission of different frequencies around the arm could potentially give data on hydration or body fat or even changes in blood volume.