Call for a Post-Doctoral position Nonlinear laser ultrasonic imaging techniques for MEMS reliability assessment Starts in summer-autumn 2012, 12 months. Acoustic Laboratory of the Université du Maine (LAUM), CNRS UMR-CNRS 6613, Le Mans, France http://laum.univ-lemans.fr/

CONTEXT Ultrasonic waves are widely used to measure non-destructively mechanical properties of liquids and solids and to control materials/structures damage. The opto-acousto-optic techniques, in which ultrasonic waves are both generated and detected by lasers, are receiving growing attention because of their wide range of applicability in non-destructive evaluation. These techniques are particularly well suited for materials/structures characterization when measurements have to be done without contact and at micrometric spatial scale. One of the promising opportunities to improve sensitivity and functionality of all-optical methods of materials/structures evaluation and imaging contrast is to develop techniques sensitive to the nonlinear elastic/inelastic properties of the materials and such damage features as cracks, delaminations… Nonlinear acoustics methods are extremely sensitive in characterization of non-perfectly contacting materials surfaces, cracks and fatigue damage through the monitoring of such nonlinear acoustic phenomena as harmonic generation, subharmonic generation, parametric modulation modulation transfer and rectification. The research team in the Acoustic Laboratory of the Université du Maine (LAUM) in Le Mans, France, has established experience in nonlinear acoustics [V. Tournat, B. Castagnède and V. Gusev, Materials and Acoustics Handbook (ISTE-Wiley, London, New-York, 2009), Chapter 18, 473-504], in laser ultrasonics [N. Chigarev, et al., Appl. Phys. Lett. 93, 181905 (2008).] and has recently started applications of all-optical probing of the nonlinear acoustic phenomena in non-detsructive testing [S. Mezil, N. Chigarev, V. Tournat, V. Gusev, Opt. Lett. 36, 3449-3451 (2011)].

PROJECT The present fundamental research and experimental development project is dedicated to the use of new nonlinear acoustic imaging techniques for non-destructive testing of Micro-Electro-Mechanical Systems (MEMS) reliability. The goal here is to develop and apply new original nonlinear acoustic methods for defects characterization and imaging of MEMS in the frequency range of 0-10 GHz. The technique, which will be developed in LAUM in the frame of the project, is an Opto-Acousto-Optical method that uses lasers both for generation of sound waves and for detection of the nonlinear acoustic response of cracks, thus representing a fully non contact procedure. COLLABORATIONS The major collaborator is: Institute of Electronics, Microelectronics and Nanotechnologies, UMR CNRS 8520, Lille, France http://www.iemn.univ-lille1.fr/ REQUIRED QUALIFICATIONS AND EXPERIENCE OF THE CANDIDATES The candidate should have documented experience in experimental physics involving high-precision laser techniques demanding knowledge of the principles and methods of sound waves photo-generation and photodetection. Knowledge of laser ultrasonics and basic principles of nonlinear acoustics will be advantageous. Skills in data processing are also important. NET SALARY: 25 000 €/year from the French National Agency for Research (ANR) CONTACTS Dr. Nikolay Chigarev, Phone: 33 (0)2 43 83 36 81, Email: [email protected] Prof. Vitalyi Gusev , Email: [email protected] Qualified persons interested to work in the above field and having relevant expertise are invited to e-mail their applications, including a statement of interest besides the usual documents (CV, publication list, addresses of the researchers from whom the recommendation letters could be requested).