Optical method for the measurement of the thermomechanical behaviour of electronic devices

We present in this paper a laser probing method for the study of the surface deformation and thermomechanical behaviour of electronic components. The method has been applied to running power devices and creep analysis of solder joints in after-fabrication processes. The set-up allows following the whole surface deformation as a function of time even in the long-term range. The method is based upon electronic speckle pattern interferometry (ESPI) and allows measuring surface normal deformation with a 10nm resolution. © 1999 Elsevier Science Ltd. All rights reserved.