Viewpoints

About This Technology

Each year, over a billion sensor chips find use in new cars, cell phones, game controllers, industrial equipment, and much more. Like other sensors, solid-state microsensors (SSMs) detect and respond to stimulation such as pressure, speed, acceleration, and chemical concentration. Compared to other kinds of sensors, SSMs are typically cheaper and smaller due to 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 multi-axis accelerometers and gyroscopes for cell phones. Current technology and business developments seek to apply solid-state microsensors to enhance healthcare, security, energy efficiency, environmental protection, and other vital needs. And current precommercial efforts envision SSMs playing disruptive roles—as part of ubiquitous wireless sensor networks, embedded in everyday objects, and implanted in our bodies.

The first uses of silicon solid-state microsensors 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 accelerometers have seen similar market growth in automotive, consumer, and industrial uses, including actuating airbags, controlling ride, controlling handheld electronic devices via tilting, and monitoring vibration for industrial machinery. Although less developed, the market for chemical microsensors promises to grow for applications including in situ blood-monitoring devices and handheld units for field chemical analysis. Advanced chemical microsensors also await further development but are increasingly finding use in domestic alarms, portable analyzers, HVAC systems, combustion monitoring, and medical applications. A multitude of new markets and applications for solid-state microsensors will continue to emerge, as the price of sensors drops further and as the sensors acquire increased intelligence and networking capability. Advances in sensor packaging, design, and fabrication open new performance-sensitive applications for microsensor technology.

Solid-state microsensors will continue to displace conventional electromechanical sensors, particularly in high-volume markets. OEMs will use electronic microsensors to add functions and improve the reliability of their products with no cost or size penalties, especially in automotive and consumer electronics applications. Industrial end users will use microsensors in an expanding number of process-control and manufacturing applications, even incorporating these sensors into fabricated materials. The medical industry sees microsensors as a boon to the continuous and direct monitoring of critical patient variables such as blood pressure and blood chemistry; plus, they 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 multisensory data fusion, integration of wireless sensors, and 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.