Optical Micromachined Ultrasound Transducers (OMUT) – a New Approach for High Resolution Imaging

M. A. Tadayon; S. Ashkenazi

doi:10.1117/12.2000673

4 March 2013 Optical micromachined ultrasound transducers (OMUT) - a new approach for high resolution imaging

M. A. Tadayon, S. Ashkenazi

Proceedings Volume 8581, Photons Plus Ultrasound: Imaging and Sensing 2013; 858115 (2013) https://doi.org/10.1117/12.2000673
Event: SPIE BiOS, 2013, San Francisco, California, United States

Abstract

Piezoelectric ultrasound (US) transducers are at the heart of almost any ultrasonic medical imaging probe. However, their sensitivity and reliability severely degrade in applications requiring high frequency (>20 MHz) and small element size (<0.1 mm). Alternative technologies such as capacitive micromachined ultrasound transducers (CMUT) and optical sensing and generation of ultrasound are being investigated. In this paper we present our first steps in developing optical micromachined ultrasound transducers (OMUT) technology. OMUTs rely on microfabrication techniques to construct micron-size air cavities capped by an elastic membrane. The membrane functions as the active ultrasound transmitter and receiver. We will describe the design and testing of prototype OMUT devices which implement a receive-only function. The cavity detector is an optical cavity which its top mirror is deflected under the application of pressure. The intensity of a reflected light beam is highly sensitive to displacement of the top membrane if the optical wavelength is at near-resonance condition. Therefore, US pulses can be detected by recording the reflected light intensity. The sensitivity of the device depends on the mechanical properties of the top membrane and optical characteristics of the optical cavity. The device was fabricated using SU8 as a structural material and gold as a mirror. We have developed a new bonding method to fabricate a sealed, low roughness, high quality optical cavity. The 60μm cavity with the 8.5 μm top membrane is tested in water with 25MHz ultrasound transducer. The NEP of the device for bandwidth of 28MHz was 9.25kPa. The optical cavity has a finesse of around 23.

Citation Download Citation

M. A. Tadayon and S. Ashkenazi "Optical micromachined ultrasound transducers (OMUT) - a new approach for high resolution imaging", Proc. SPIE 8581, Photons Plus Ultrasound: Imaging and Sensing 2013, 858115 (4 March 2013); https://doi.org/10.1117/12.2000673

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
7 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Ultrasonography

Mirrors

Transducers

Optical resonators

Semiconducting wafers

Sensors

Gold

Show All Keywords

Keywords/Phrases

Search In:

Publication Years