Skip to Main content Skip to Navigation
New interface
Theses

Etude de membranes ultra-fines pour intégration de transducteurs acoustiques ultra-sonores

Abstract : This thesis concerns a context of miniaturization of micromachined ultrasonic transducers (cMUTs). This type of device has been used for decades in the field of ultrasound imaging for the non-destructive testing of structures for example. The quest of a highly resolved imaging requires the use of cMUTs with a resonance frequency in the order of GHz and with a micrometer size. The main part of these cMUts is a suspended membrane with a micrometric surface. An analytical study, based on the mechanical behavior of thin plates, is used for the design of the suspended membranes. This study emphasizes the importance of having a nanometric thickness to obtain a detectable electrical signal. Several materials, namely carbon nanotubes, graphene, graphene oxide, DLC (diamond like carbon ) and silicon have been implemented in this study to make a micron size suspended membranes with a nanometric thickness . Technological processes specific to each of these materials have been designed. Suspended membranes with thicknesses ranging from 2 to 15 nm and widths ranging from 1 to 2 microns were made. A novel method of characterization has been established to evaluate the mechanical properties of our membranes. A measurement protocol has been developed to measure the of displacement of the suspended membrane under the an electrostatic field . Amplitudes reaching ten nanometers were measured. More generally , this study provides a strong proof of the feasibility of suspended micrometer-sized membranes with an electrically detectable signal.
Document type :
Theses
Complete list of metadata

https://theses.hal.science/tel-00954586
Contributor : ABES STAR :  Contact
Submitted on : Monday, March 3, 2014 - 11:52:50 AM
Last modification on : Friday, March 25, 2022 - 9:41:24 AM
Long-term archiving on: : Saturday, May 31, 2014 - 12:20:17 PM

File

36478_SRIDI_2013_archivage.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00954586, version 1

Collections

CEA | STAR | DRT | LETI | CEA-GRE

Citation

Nawres Sridi. Etude de membranes ultra-fines pour intégration de transducteurs acoustiques ultra-sonores. Autre. Université de Grenoble, 2013. Français. ⟨NNT : 2013GRENT072⟩. ⟨tel-00954586⟩

Share

Metrics

Record views

308

Files downloads

758