K. Nassim et al., High-resolution interferometry and electronic speckle pattern interferometry applied to the thermomechanical study of a MOS power transistor, MICROELEC J, 30(11), 1999, pp. 1125-1128
We present an original optical approach for the thermomechanical study of e
lectronic devices. We have applied it to image the deformation undergone by
a MOS power transistor due to its operation. This imaging method allows th
e derivation of the three components of. the displacement vector of each po
int of the surface of the component while heated by Joule effect while runn
ing. The method has a nanometric resolution for the displacement measuremen
t and is based on the analysis of the speckle structure of the device while
illuminated by coherent light. A high-resolution interferometer is also us
ed to record the transient behavior of the normal surface displacement of a
point of the surface. These optical approaches provide interesting quantit
ative information about strain and stress in electronic power devices and a
llow testing of finite element simulations. These techniques can be compare
d to Moire thermomechanical studies but with better resolution and sensitiv
ity. (C) 1999 Elsevier Science Ltd. All rights reserved.