Scheduled System Maintenance on May 29th, 2015:
IEEE Xplore will be upgraded between 11:00 AM and 10:00 PM EDT. During this time there may be intermittent impact on performance. We apologize for any inconvenience.
By Topic

CMUT as a chemical sensor for DMMP detection

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

5 Author(s)
Lee, H.J. ; Edward. L. Ginzton Lab., Stanford Univ., Stanford, CA ; Kwan Kyu Park ; Oralkan, O. ; Kupnik, M.
more authors

We present an 18-MHz capacitive micromachined ultrasonic transducer (CMUT), used as a chemical sensor for detection of a common simulant for chemical weapons, dimethyl methylphosphonate (DMMP), in air. CMUTs are attractive for chemical sensor applications because of their unprecedented mass sensitivity per membrane area, low motional impedance, and high quality factor compared to other flexural-mode resonators. The device is composed of 1000 individual cells operating in parallel, which provides a robust operation with low false alarm rate and low motional impedance comparable to that of quartz crystal resonators. We designed a CMUT-based oscillator with a phase noise of -84.8 dBc/Hz and -136.6 dBc/Hz at offset frequencies of 1 kHz and 1 MHz, respectively. The oscillator exhibits an Allan deviation of 0.6 Hz with a one-sigma error of 0.037 Hz, which translates to a theoretical limit of mass detection of 16.2 ag. The 18-MHz CMUT is functionalized with a 50-nm thick polymer layer, polyisobutylene (PIB). The described CMUT sensor demonstrates a volume sensitivity of 37.38 ppb/Hz to DMMP.

Published in:

Frequency Control Symposium, 2008 IEEE International

Date of Conference:

19-21 May 2008