FEA Distinguished Alumnus Award To Dr. Pierre Khuri-Yakub in recognition of his excellence in research and inventions in the fields ultrasonics, imaging, and sensors, and his outstanding contributions to education.
Butrus (Pierre) T. Khuri-Yakub B.E. Electrical Eng’g, American University of Beirut, 1970 M.S, Dartmouth College, 1972 Ph.D, Stanford University, 1975
Professor of Electrical Engineering Stanford University

B. T. Khuri-Yakub received the BS degree in 1970 from the American University of Beirut, the MS degree in 1972 from Dartmouth College, and the Ph.D. degree in 1975 from Stanford University, all in electrical engineering.

He joined the research staff at the E. L. Ginzton Laboratory of Stanford University in 1976 as a research associate. He was promoted to a Senior Research Associate in 1978 and to a Professor of Electrical Engineering in 1982. He has served on many university committees in the school of engineering and the department of electrical engineering. Presently, he is the co-chair of graduate admissions in the EE department at Stanford, and the deputy director of the E. L. Ginzton Laboratory.

Prof. Khuri-Yakub has been teaching both at the graduate and undergraduate levels, and his current research interests include medical imaging, micromachined ultrasonic transducers, smart bio-fluidic channels, microphones, in-situ acoustic sensors (temperature, film thickness, resist cure, ...) for monitoring and control of integrated circuits manufacturing processes, and fluid ejectors, and in the field of ultrasonic nondestructive evaluation and acoustic imaging and microscopy.

Professor Khuri-Yakub is a fellow of the IEEE, a senior member of the Acoustical Society of America, and a member of Tau Beta Pi. He is associate editor of Research in Nondestructive Evaluation, a Journal of the American Society for Nondestructive Testing.

Professor Khuri-Yakub has authored over 400 publications and has been principal inventor or co-inventor of 75 US and International issued patents.

He received the Stanford University School of Engineering Distinguished Advisor Award, June 1987, the Medal of the City of Bordeaux for contributions to NDE, 1983, and the IEEE UFFC distinguished lecturer award, 1999-2000.

Micromachined Transducers for Medical Ultrasound Imaging

Dr. Pierre T. Khuri-Yakub
Stanford University
Stanford, CA 94305-4088

Abstract

Capacitive Micromachined Ultrasonic Transducers (CMUTs) have been developed in the past decade as alternative transducers for generating and detecting ultrasound. Capacitor ultrasound transducers have been known for over 100 years; however, the advent of silicon micromachining has enabled the realization of the full potential of these transducers. Silicon micromachining allows the manufacture of capacitors with very thin gaps, and with electric fields of the order of 109 V/m that determines their performance. It is now possible to make immersion CMUTs with over 100 % fractional bandwidth, with an electromechanical coupling coefficient close to unity, and to make single element and one-dimensional (1D) and two-dimensional (2D) arrays of tens of thousand of elements, as well as annular arrays. CMUTs have been operated in the frequency range of 100 kHz to 50 MHz, and with a dynamic range of the order of 150 dB/V/Hz.

This presentation will first review the conventional mode of operation of CMUTs, and then introduce a non-conventional mode of operation with improved output pressure. Two different technologies for making CMUTs will be presented along with a technology for integrating electronics, which is one of the major advantages of this approach. Next, examples of various types of transducers will be presented, along with results of imaging in two and three dimensions.