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About This Technology

Each year, billions of sensor chips find use in new cars, cell phones, game controllers, industrial equipment, and much more. Like other sensors, solid-state microsensors detect and respond to stimulation such as pressure, speed, acceleration, and chemical concentration. In comparison with other kinds of sensors, SSMs are typically cheaper and smaller because of the use of manufacturing methods that emerged from the semiconductor-chip business. A key family of methods enables chips with small moving parts—microelectromechanical systems—and is responsible for very high volumes of sensors, especially multiaxis accelerometers and gyroscopes for cell phones and cars. Current technology and business developments seek to apply solid-state microsensors to enhance health care, security, energy efficiency, and environmental protection and to include sensors in disruptive roles such as being part of pervasive sensor networks, medical implants, and food packages.

Solid-state microsensors may have their most noticeable impacts in their roles as low-cost enhancements to smartphones, where they aid in street navigation; detect a phone's position to help manage power, control displays, and serve as game controllers; and perform other roles. In contrast, the sensors' first uses were in high-cost aerospace and military applications. As prices declined and fabrication technologies evolved, silicon pressure sensors penetrated automotive, industrial-process-control, and medical applications. Silicon inertial sensors have seen similar market growth in automotive, consumer, and industrial uses, including actuating airbags, controlling ride, tracking daily physical activity, and monitoring vibration for industrial machinery. Together with solid-state compasses, silicon inertial sensors have become ubiquitous in automotive- and smartphone-navigation systems. Although less developed, the market for chemical and gas microsensors promises to grow for applications including in situ blood-monitoring devices and handheld units for field analysis. Advanced chemical and gas microsensors also await further development but are increasingly finding use in domestic alarms, portable analyzers, HVAC systems, combustion monitoring, and medical applications.

As the price of sensors drops further, SSMs will continue to enable new high-volume markets and to displace conventional sensors. Advances in sensor packaging, design, and fabrication will yield new performance-sensitive applications. And high-value-added applications will emerge as the sensors acquire increased intelligence and networking capability. OEMs will use electronic microsensors to add functions, reduce cost, miniaturize, and improve product reliability. Industrial end users will use microsensors in an expanding number of process-control and manufacturing applications, even incorporating these sensors into fabricated materials. Physicians see microsensors as a boon to the continuous and direct monitoring of critical patient variables such as blood pressure and blood chemistry; plus, microsensors allow monitoring to take place in the home. Eventually, SSM chemical sensors may also find common use for monitoring food quality, screening airport travelers for explosives and other dangerous substances, and detecting toxic substances in the environment, Many of these future applications will likely benefit via fusing data from multiple sensors (sensor fusion), integrating wireless sensors, and using services that make sense of sensor data. The logical high-tech counterparts to sophisticated microprocessors, solid-state microsensors will be essential components in future systems that sense, evaluate, and act intelligently in response to environmental stimuli.