Electrical heating synchronized with IR imaging to determine thin film defects.

Measuring conductive thin film properties during production and in end products is a challenge. The main demands for the measurements are: production control, reliability and functionality in final applications. There are several ways to measure thin film quality in a laboratory environment, however these methods are poorly applicable for production facilities. In order to bypass the limitations of existing methods, a simple synchronized heating and IR-imaging based system was implemented. To demonstrate the proposed method, Indium Tin Oxide (ITO) was selected as an example of conductive thin films. PET-ITO films were bent to obtain samples with defects. The proposed method was used and automated signal processing was developed. The results show that the system developed here is suitable for defining breakage types and localizing defects.

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