October 3, 2011 — In 2006, the global market for micro-electromechanical system (MEMS) devices, which at that time included automobile airbag systems, display systems and inkjet cartridges, totaled $5.9 billion. That initial success may have been driven by the use of air-bag accelerometers in the automotive market, but the true commercialization of MEMS motion sensors began in 2005-2006 with consumer electronics and mobile phones. In fact, because of increased adoption and new applications in consumer and mobile applications, Yole Développement is now projecting double-digit annual growth in MEMS from the $8.7 billion reported in 2010, to $19.6 billion projected in 2016.
In the consumer and mobile markets, MEMS accelerometers and gyroscopes today enable cost-effective innovation, creation, and success of various motion-activated or motion-aware devices. Sensors add an intuitive man/machine interface to mobile phones and music/video players, PDAs, tablets and game controllers, by linking movements of the user’s wrist, arm, and hand to applications, navigation within and between pages, the movement of characters in a game, and much more. Almost every consumer device or cell phone today has a motion sensor embedded inside.
This successful commercialization of motion sensors was accelerated by the continual perfection of manufacturing techniques using extensions of the same high-volume, low-cost batch fabrication techniques that the semiconductor industry has used for decades. With these techniques, MEMS have achieved greater reliability and lower cost. One of the first manufacturers to dedicate an 8” wafer fabrication line solely to MEMS, STMicroelectronics, has made MEMS a centerpiece of its “Sense and Power” activities and this focus has led to further reduction in unit costs as well as higher degrees of innovation and integration.
But the emphasis on simply meeting demand wasn’t enough. As developers learned how to use the motion sensors for simple applications, they also gained trust in the performance and reliability of these sensors, built in-house sensor expertise, and were encouraged to develop more advanced applications that required even higher performance sensors.
Manufacturers throughout the MEMS industry are rising to that challenge. The future trend is to provide multi-sensor modules and deploy dedicated sensor fusion algorithms to make multiple sensors play well together. Sensor fusion is the core element for developing high-end applications, such as location-based services and dead reckoning.
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| Figure 1. The mechanical structure of the driving and sensing elements of a 3-axis gyroscope includes flexing silicon “fingers” that help the MEMS gyroscope detect changes in pitch, yaw and roll. SOURCE: STMicroelectronics. |
At the forefront of MEMS sensor fusion development is the integration of multiple sensors, such as accelerometers, gyroscopes, magnetometers, and pressure sensors- in one package (Fig. 1). This approach is leading to giant leaps in functionality and performance in a wide variety of applications. One example of this integrated sensor approach is ST’s iNEMO. In these multi-sensor products, integrated sensors enable autonomous and automated systems by monitoring specific conditions and turning the detection of those conditions into actions with minimal or no user intervention required. Further, smart sensors combine MEMS devices with integrated processing capability to run the sensing-related algorithms independent of the main processor unit and thereby decrease overhead and, more importantly, power consumption, at the system level, which is especially crucial in battery-hungry portable devices.
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| Figure 2. The movements of a MEMS gyroscope bear a strong resemblance to a beating heart. SOURCE: STMicroelectronics. |
We have been able to leverage the iNEMO Engine’s filtering and predictive software (that fuses the data from all the sensors) in multi-sensor modules. We fully expect that sensor fusion will significantly contribute to further commercialization of existing inertial sensors, while also accelerating the adoption of even more sensors into the consumer electronics devices and smart phones.
Jay Esfandyari is MEMS Product Marketing Manager at STMicroelectronics, 750 Canyon Dr, Suite 300, Coppell, TX, (972) 466-7619, [email protected].
This blog is provided by MEMS Industry Group (MIG). Read the first blog in this series: MEMS product development — why is it so hard? by Karen Lightman, MEMS Industry Group and Alissa M. Fitzgerald, A.M. Fitzgerald & Associates and MEMS Industry Group.