Size of micro thermal flow sensor

In the pursuit of human-centered automation, the azbil Group is striving to solve the problems its customers face, contribute to the global environment, promote the introduction of renewable energy and support energy-saving measures. In advancing these efforts, it is important to not only manage the fluids used as fuels and power sources but also to measure the mass flow rates that are crucial for energy efficiency.

Azbil's micro thermal flow sensor provides highly accurate mass flow rate measurements. It is made by forming a diaphragm, a thin membrane just 1 micron thick, on a silicon chip that is 1.7 mm square—smaller than a grain of rice—with a heater in the center of the diaphragm and temperature sensors on either side of it.

The development of these tiny sensors is supported by Azbil's proprietary advanced MEMS technology, which employs the microfabrication technology used in creating nano- to micron-scale structures to manufacture tiny devices and systems that incorporate mechanical, electrical, and thermal elements. MEMS stands for microelectromechanical system. They are not simply structures made by microfabrication, but are also ultra-small devices/systems which utilize microfabrication technology to operate and function, and are incorporated into products in a wide range of fields, with applications that include miniaturization, power saving, and increasing the functionality of equipment.

Azbil has been focusing on the potential of MEMS since the 1980s and has been conducting its own research and development into MEMS. It first started development with micro thermal flow sensors that measure low flow rates. Since then, it has expanded to developing flow sensors for high flow rates, as well as flow sensors with an integrated flow channel structure, which involves bonding a micro flow channel to the surface of the sensor chip. This enables highly accurate measurement and control over a wide range of flow rates, from minute flow rates of 5 mL/min to 2,500 L/min. Through these endeavors, Azbil is developing a variety of sensors and incorporating them into its products.

As generative AI evolves and digital transformation (DX)^*1 is promoted, the scope of application for MEMS is expected to expand even further in the future. Azbil will continue to enhance its MEMS technical capabilities based on its measurement and control technologies, and will promote the commercialization of MEMS-based products to meet the needs of its customers and the market.