Reliable hot-spot classification in 10 ms using ultra-fast lock-in thermography

• Published in: Progress in photovoltaics Vol. 17; no. 7; pp. 441 - 450
• Main Authors: Kasemann, Martin, Walter, Benjamin, Warta, Wilhelm
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.11.2009; Wiley
• Subjects: Applied sciences; Categories; characterization; Classification; Cooling; Energy; Exact sciences and technology; hot-spot; lock-in thermography; Natural energy; Nondestructive testing; Photovoltaic cells; Photovoltaic conversion; Silicon; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Solar cell; Measurement; Ultrafast technique; Silicon solar cells; lock-in thermography; Accuracy; hot-spot; Thin film cell; Measurement technique; Hot spot; characterization; Thermography
• ISSN: 1062-7995; 1099-159X; 1099-159X
• DOI: 10.1002/pip.901

We propose and demonstrate a reliable and non‐destructive spatially resolved measurement technique for ultra‐fast hot‐spot classification of solar cells. The method can deliver quantitative images of the local heat dissipation in hot‐spots in measurement times below 10 ms. The high accuracy and sensitivity allow for reliable hot‐spot testing and provide the basis for a reliable classification of solar cells into different hot‐spot categories. The method can be applied to wafer‐based silicon solar cells and in principle also to thin‐film solar cells of all material compositions. This paper explains the measurement principle, gives a detailed step‐by‐step description of viable automated evaluation procedures, and assesses the sensitivity and accuracy of the method. Copyright © 2009 John Wiley & Sons, Ltd. We propose and demonstrate a fast, reliable and quantitative spatially resolved measurement technique for in‐line hot‐spot classification of solar cells. The paper explains the measurement principle, gives a detailed step‐by‐step description of viable automated evaluation procedures, and assesses the sensitivity and accuracy of the method.