Applications of Silicon in MEMS Devices

By AZoNano Staff Writers

Table of Contents

Introduction
Advantages of Silicon in MEMS Devices
Types of Silicon MEMS components
    Electronics
    Actuators
    Sensors
About University Wafer

Introduction

MEMS (microelectromechanical systems) are microdevices that are developed using techniques from integrated circuit processing. Capabilities of MEMS include mechanical, fluidic, electrical and thermal functions.

Their small size enables their use in applications which are inaccessible to conventional devices, and there can often be performance advantages due to favorable scaling effects as well.

Image credit: Thinkstock

Advantages of Silicon in MEMS Devices

Silicon is the primary substrate material used to create both microelectronics and MEMS devices.

Processing methods such as etching and photolithography have been thoroughly developed by the electronics industry, and can be adapted for MEMS production much more easily than new techniques can be created and tested.

For this reason, the vast majority of MEMS are created on silicon wafers.

The mechanical stability and semiconductivity of silicon also make it ideal for use in the structures of electromechanical devices themselves.

Additional advantages to using silicon in MEMS devices include:

  • Silicon is nearly as light as aluminum and has a density of 2.3 g/cm3

  • It has an incredibly high melting point--nearly 1400 centigrade (2500 degrees Fahrenheit)--that makes it stable dimensionally even at inflated temperatures

  • Because silicon exhibits minimal mechanical hysteresis, it represents an ideal material for use in actuators and sensors

  • Silicon wafers designed as coatings or layers for structural parts integral to the functioning of an MEMS device allow for optimal precision operations during specific electromechanical functions

Image credit: Thinkstock

Types of Silicon MEMS Components

Electronics

Most MEMS devices require some standard electronic chips, to add signal processing or logic capabilities. As silicon is the primary material used to create microelectronics for all applications, it will be seen in all MEMS devices, whether as part of a third part chip, or in a custom-designed component, processor or ASIC.

Actuators

Most functional microstructures in MEMS are also made from polycrystalline silicon, or polysilicon. Polysilicon has almost perfect mechanical properties for use in microdevices, which has led to the development of a number of different approaches to creating microactuators which all use silicon as the main material in the device.

Microactuators controlled electrically, magnetically, thermally and optically have all been developed using silicon as the primary material component

Sensors

Sensors based on silicon have been developed for a wide range of applications – temperature sensing, inertial sensors/accelerometers, chemical sensors, mass flow sensors, and pressure sensors, amongst others.

The electromechanical properties of silicon mean that sensors using it can be designed around a number of different effects – such as the piezoresisitive effect, or resonance in single-crystal silicon. Research is ongoing to discover and optimize new sensing methods using silicon.

About University Wafer

University Wafer was developed to provide researchers with wafers and other semiconductor related materials and services inexpensively and in a timely manner.

University Wafers supplies wafers ranging from as thin as 5 microns to as thick as a silicon ingot, and are able to supply single wafers or orders of any size. Most of our silicon items are in stock or can ship in just a few short weeks to any destination.

Wafers can have oxides, nitrides, or metals deposited on their surface. They can be diced, and thinned to 5um. Undoped, low doped and highly doped wafers are always in stock.

For more information, please contact University Wafer.

Date Added: Apr 28, 2014 | Updated: Apr 29, 2014
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