IR-imaging based system for detecting the defects of conductive materials

Kimmo Leppänen; Juha Saarela; Tapio Fabritius

doi:10.1117/12.2060834

5 September 2014 IR-imaging based system for detecting the defects of conductive materials

Kimmo Leppänen, Juha Saarela, Tapio Fabritius

Proceedings Volume 9205, Reflection, Scattering, and Diffraction from Surfaces IV; 92050M (2014) https://doi.org/10.1117/12.2060834
Event: SPIE Optical Engineering + Applications, 2014, San Diego, California, United States

Abstract

Uniformity of conductive materials is an important property which is measured during manufacturing and in finished products, especially in electronics applications such as organic solar cells. Differences in uniformity are often very small, invisible or below the surface of the sample. Therefore, they are not always detectable even by high-resolution imaging systems. Respectively, electrical conductivity measurements are limited to those mainly between the measuring probes. Uniformity difference measurements are time-consuming in the case of a large area characterization. To bypass the described limitations, a simple heating and IR-imaging based system was designed and demonstrated with conductive materials. Samples with different defects were used to investigate the correlation of conductance and defect positioning. By making punched holes in the samples, it was possible to demonstrate how the local resistances of thin films have functions to each other and how this may be observed on an IR-figure. Thermographs of punched thin films confirm that those areas where the holes prevented the current flow have lower heat emissions. Therefore, it can also be concluded that, generally, the temperature is highest at the areas where current density is highest. When comparing the defects of bent samples to these punctured ones, the correlations of resistance and breakage areas were comparable. The applied system is capable of localizing small defects in large-area samples using a single IR-image. This is a significant advantage from the manufacturing process measurement point of view.

Citation Download Citation

Kimmo Leppänen, Juha Saarela, and Tapio Fabritius "IR-imaging based system for detecting the defects of conductive materials", Proc. SPIE 9205, Reflection, Scattering, and Diffraction from Surfaces IV, 92050M (5 September 2014); https://doi.org/10.1117/12.2060834

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available