2D thermal MEMS accelerometer

A 2D thermal MEMS accelerometer uses a monolithic approach that integrates the sensor and electronics onto the IC which is then hermetically sealed in a package. The silicon die includes a heating element and thermopiles suspended over a cavity etched into the die. Instead of using capacitance to measure force, the thermal sensor uses the movement of the heated gas molecules to detect acceleration. With acceleration, the heated molecules move in the direction of acceleration, and with zero acceleration the heated gas is symmetrical above the heater. These devices have no flexing or moving parts, which make them more durable and delivers very high measurement repeatability.

Read more

SiliconMicromachined Pressure Sensors - a Review

Silicon micromachining for realizing micro mechanical structures has received considerable interest due to the several advantages of this technology over the conventional machining techniques. Silicon pressure sensors were the first micro mechanical transducers developed. Since then the market for micromachined pressure sensors has grown in leaps and bounds and found application in all walks of life including defense and space applications. The relevant micromachining technology and the design considerations are reviewed in this paper. The paper also gives the latest developments in this area and gives the details of the polysilicon piezoresistor based pressure sensors with Silicon On Insulator (SOI) approach for integrating pressure sensor and associated electronics.

Prof. K.N. Bhat, IISC Bangalore

SiliconMicromachined Pressure Sensors