01EC6102 - MEMS -Slides

• Introduction

• Material and Scaling Laws

• Sensors and Actuators

MEMS EC 465 Slides - 3

14_Bulk Micromachining

15_Surface Micromachining

16_Micromolding techniques

17_Micro Stereo lithography

18_Wafer bonding

19_Emerging Areas_MEMS

MEMS EC 465 Slides

01_MEMS History and Development

02_Sensors and Actuators 

03_Review of Mech

04__Thermal_sensors_and_Actuators

Handouts April 2018

NEMS 

BioMEMS (extra slides)

Etch Rates for Micromachining Processing

When designing a microfabrication process, the etch rate of each material to be etched must be known. Knowing the etch rates of other materials that will be exposed to the etch, such as masking films and underlying layers, enables an etch process to be chosen for good selectivity (high ratio of etch rate of the target material to etch rate of the other material)—if one exists. These two papers compare the etch rates of different materials in various etchants

K. R. Williams and R. S. Muller, "Etch rates for micromachining processing," in Journal of Microelectromechanical Systems, vol. 5, no. 4, pp. 256-269, Dec 1996.

K. R. Williams, K. Gupta and M. Wasilik, "Etch rates for micromachining processing-Part II," in Journal of Microelectromechanical Systems, vol. 12, no. 6, pp. 761-778, Dec. 2003.
doi: 10.1109/JMEMS.2003.820936

Etch rates for Micromachining Processing - Part 1

Etch rates for Micromachining Processing - Part 2

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.

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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