# Suspended Large-Area MEMS-Based Optical Filters for Multispectral Shortwave Infrared Imaging Applications

Research output: Contribution to journalArticle

3 Citations (Scopus)

### Abstract

© 1992-2012 IEEE. We present the design, fabrication, and optical and mechanical characterization of silicon-/silicon-oxide-based optical filters and distributed Bragg reflectors in sizes ranging from 500 ~\mu {\rm m} \times 500 ~\mu {\rm m} to 5~{\rm mm} \times 5~{\rm mm}. They are designed to be used in conjunction with either single-element photodetectors or large-area focal plane arrays to realize tunable multispectral sensors or adaptive focal plane arrays in the shortwave infrared wavelength range. Surface optical profile measurements indicate a flatness of the order of 30 nm in the fabricated structures across several millimeters. Single-point spectral measurements on devices show an excellent agreement with simulated optical models, and demonstrate Si-SiOx-Si fixed optical filters with a 94% transmission at 1940 nm with a full-width at half-maximum of 250 nm. Distributed Bragg reflectors demonstrate 90% reflectance across the 1560-2050-nm wavelength range, making them suitable as broadband reflectors. The optical spatial uniformity across a 3-mm \times 3 -mm device shows only a 3% variation across the entire optically active area. Finally, the mechanical resonance characteristic of a 1-mm \times 1 -mm fabricated device shows the lowest resonant frequency of the suspended structure to be 39 kHz, indicating excellent immunity to extraneous low-frequency vibrations. [2014-0278]
Original language English 1102-1110 Journal of Microelectromechanical Systems 24 4 https://doi.org/10.1109/JMEMS.2014.2385081 Published - Aug 2015

### Fingerprint

Distributed Bragg reflectors
Focal plane arrays
Optical filters
Infrared imaging
MEMS
Wavelength
Silicon oxides
Photodetectors
Full width at half maximum
Natural frequencies
Fabrication
Silicon
Sensors

### Cite this

title = "Suspended Large-Area MEMS-Based Optical Filters for Multispectral Shortwave Infrared Imaging Applications",
abstract = "{\circledC} 1992-2012 IEEE. We present the design, fabrication, and optical and mechanical characterization of silicon-/silicon-oxide-based optical filters and distributed Bragg reflectors in sizes ranging from 500 ~\mu {\rm m} \times 500 ~\mu {\rm m} to 5~{\rm mm} \times 5~{\rm mm}. They are designed to be used in conjunction with either single-element photodetectors or large-area focal plane arrays to realize tunable multispectral sensors or adaptive focal plane arrays in the shortwave infrared wavelength range. Surface optical profile measurements indicate a flatness of the order of 30 nm in the fabricated structures across several millimeters. Single-point spectral measurements on devices show an excellent agreement with simulated optical models, and demonstrate Si-SiOx-Si fixed optical filters with a 94{\%} transmission at 1940 nm with a full-width at half-maximum of 250 nm. Distributed Bragg reflectors demonstrate 90{\%} reflectance across the 1560-2050-nm wavelength range, making them suitable as broadband reflectors. The optical spatial uniformity across a 3-mm \times 3 -mm device shows only a 3{\%} variation across the entire optically active area. Finally, the mechanical resonance characteristic of a 1-mm \times 1 -mm fabricated device shows the lowest resonant frequency of the suspended structure to be 39 kHz, indicating excellent immunity to extraneous low-frequency vibrations. [2014-0278]",
author = "Dhirendra Tripathi and F. Jiang and Ramin Rafiei and Silva, {K.K.M.B. Dilusha} and Jarek Antoszewski and Mariusz Martyniuk and John Dell and Lorenzo Faraone",
year = "2015",
month = "8",
doi = "10.1109/JMEMS.2014.2385081",
language = "English",
volume = "24",
pages = "1102--1110",
journal = "Journal of Microelectromechanical Systems",
issn = "1057-7157",
publisher = "IEEE, Institute of Electrical and Electronics Engineers",
number = "4",

}

In: Journal of Microelectromechanical Systems, Vol. 24, No. 4, 08.2015, p. 1102-1110.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Suspended Large-Area MEMS-Based Optical Filters for Multispectral Shortwave Infrared Imaging Applications

AU - Tripathi, Dhirendra

AU - Jiang, F.

AU - Rafiei, Ramin

AU - Silva, K.K.M.B. Dilusha

AU - Antoszewski, Jarek

AU - Martyniuk, Mariusz

AU - Dell, John

AU - Faraone, Lorenzo

PY - 2015/8

Y1 - 2015/8

N2 - © 1992-2012 IEEE. We present the design, fabrication, and optical and mechanical characterization of silicon-/silicon-oxide-based optical filters and distributed Bragg reflectors in sizes ranging from 500 ~\mu {\rm m} \times 500 ~\mu {\rm m} to 5~{\rm mm} \times 5~{\rm mm}. They are designed to be used in conjunction with either single-element photodetectors or large-area focal plane arrays to realize tunable multispectral sensors or adaptive focal plane arrays in the shortwave infrared wavelength range. Surface optical profile measurements indicate a flatness of the order of 30 nm in the fabricated structures across several millimeters. Single-point spectral measurements on devices show an excellent agreement with simulated optical models, and demonstrate Si-SiOx-Si fixed optical filters with a 94% transmission at 1940 nm with a full-width at half-maximum of 250 nm. Distributed Bragg reflectors demonstrate 90% reflectance across the 1560-2050-nm wavelength range, making them suitable as broadband reflectors. The optical spatial uniformity across a 3-mm \times 3 -mm device shows only a 3% variation across the entire optically active area. Finally, the mechanical resonance characteristic of a 1-mm \times 1 -mm fabricated device shows the lowest resonant frequency of the suspended structure to be 39 kHz, indicating excellent immunity to extraneous low-frequency vibrations. [2014-0278]

AB - © 1992-2012 IEEE. We present the design, fabrication, and optical and mechanical characterization of silicon-/silicon-oxide-based optical filters and distributed Bragg reflectors in sizes ranging from 500 ~\mu {\rm m} \times 500 ~\mu {\rm m} to 5~{\rm mm} \times 5~{\rm mm}. They are designed to be used in conjunction with either single-element photodetectors or large-area focal plane arrays to realize tunable multispectral sensors or adaptive focal plane arrays in the shortwave infrared wavelength range. Surface optical profile measurements indicate a flatness of the order of 30 nm in the fabricated structures across several millimeters. Single-point spectral measurements on devices show an excellent agreement with simulated optical models, and demonstrate Si-SiOx-Si fixed optical filters with a 94% transmission at 1940 nm with a full-width at half-maximum of 250 nm. Distributed Bragg reflectors demonstrate 90% reflectance across the 1560-2050-nm wavelength range, making them suitable as broadband reflectors. The optical spatial uniformity across a 3-mm \times 3 -mm device shows only a 3% variation across the entire optically active area. Finally, the mechanical resonance characteristic of a 1-mm \times 1 -mm fabricated device shows the lowest resonant frequency of the suspended structure to be 39 kHz, indicating excellent immunity to extraneous low-frequency vibrations. [2014-0278]

U2 - 10.1109/JMEMS.2014.2385081

DO - 10.1109/JMEMS.2014.2385081

M3 - Article

VL - 24

SP - 1102

EP - 1110

JO - Journal of Microelectromechanical Systems

JF - Journal of Microelectromechanical Systems

SN - 1057-7157

IS - 4

ER -