Nano Science and Technology InstituteNano Science and Technology Institute
Nano Science and Technology Institute 2004 NSTI Nanotechnology Conference & Trade Show
Nanotech 2004
BioNano 2004
Topics & Tracks
Index of Authors
Business & Investment
2004 Sub Sections
Venue 2004
Press Room
Purchase CD/Proceedings
NSTI Events
Site Map
Nanotech Proceedings
Nanotechnology Proceedings
Supporting Organizations
Nanotech Supporting Organizations
Media Sponsors
Nanotech Media Sponsors
Event Contact
696 San Ramon Valley Blvd., Ste. 423
Danville, CA 94526
Ph: (925) 353-5004
Fx: (925) 886-8461

A MOEMS Electrothermal Grating

E.P. Furlani
Eastman Kodak Research Labs, US

Keywords: MOEMS grating, electrothermal diffraction grating, thermoelastic grating, electrothermal light modulator

We present a thermoelastically driven MOEMS light modulator in the form of an ElectroThermal Grating (ETG). The ETG consists of an array of equally spaced bilayer microbeams suspended at both ends above a substrate (Fig. 1). The bilayer microbeams have a conductive/reflective top layer that has highly resistive end sections, and a central portion with low resistance, and a nonconductive bottom layer. In an unactivated state, the microbeams are flat and the ETG reflects incident light like a mirror (Fig. 2a). Light modulation occurs when a potential difference is applied across the conductive layers of alternate microbeams. This causes current to flow through the resistive end sections which, in turn, expand due to joule heating. The top sections expand more than the corresponding bottom sections, which have a lower coefficient of thermal expansion. This causes a thermoelastically induced deformation of the heated microbeams downward, toward the substrate. A diffraction pattern is produced when the heated microbeams deform a distance of / 4 £f from their rest position ( £f is the wavelength of the incident light) (Fig. 2b). Since the deformation depends on the level of current, an ETG can operate in an analog mode wherein it selectively diffracts a range of wavelengths. In this presentation, we demonstrate the performance of an ETG. We present an analytical design formula for rapid parametric optimization, and demonstrate ETG viability at operating voltages below one volt.

Nanotech 2004 Conference Technical Program Abstract

Nanotech Sponsors
News Headlines
NSTI Online Community

© Nano Science and Technology Institute, all rights reserved.
Terms of use | Privacy policy | Contact