Packaging of electronic and photonic components requires high accuracy, which needs to be verified in the process of manufacturing and testing. Since very small misalignments and/or deformations can lead to unacceptable performance, a measurement approach is needed that would reveal displacements as small as a few tens of nanometers or less. In addition, misalignments and deformations occur both in the out-of-plane and in-plane directions, which may be very difficult to separate from each other. It was previously demonstrated that the two types of measurements can be implemented with different approaches: holographic interferometry for out-of-plane and Moiré interferometry for in-plane, but it is very desirable to have a single system with sufficient accuracy in both lateral and longitudinal directions. An optical technique developed by our group and presented in this paper is based on a holographic approach and combines the principles of holographic interferometry and phase modulating adaptive optics that could provide in-plane and out-of-plane measurements with high accuracy.

Date Published: 14 May 2015
PDF: 9 pages
Proc. SPIE 9489, Dimensional Optical Metrology and Inspection for Practical Applications IV, 94890J (14 May 2015); doi: 10.1117/12.2182306

Published in SPIE Proceedings Vol. 9489:
Dimensional Optical Metrology and Inspection for Practical Applications IV
Kevin G. Harding; Toru Yoshizawa, Editor(s)