Technical Diagnostics and Non-Destructive Testing, 2026, №02

2026 №02 (01)

DOI of Article 10.37434/tdnk2026.02.02

2026 №02 (03)

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"Tekhnichna Diahnostyka ta Neruinivnyi Kontrol" (Technical Diagnostics and Non-Destructive Testing) #2, 2026, pp. 13-16

Infrared termography of solar cells with a thermogenerating layer based on varizone semiconductors

V.O. Storozhenko, O.V. Miahkyi, R.P. Orel, S.M. Meshkov

RTC «Thermocontrol» of Kharkiv National University of Radio Electronics. 14 Nauky Ave., 61166, Kharkiv, Ukraine. E-mail: roman.orel@nure.ua

This study investigates the potential application of infrared thermography for integrity testing of modern solar cells with an additional thermogenerating layer based on varizone semiconductors (in particular, Si-Ge solid solutions). A comprehensive thermoelectric model of a multilayer structure has been developed and analysed, combining classical thermophysical equations with thermoelectric models of charge geion and transport in a varizone structure. Unlike standard approaches, the model accounts for the fact that the formation of a temperature signal from a defect is caused not only by a local change in thermophysical characteristics but also by a deterioration in heat dissipation due to the suppression (discontinuation) of charge carrier generation in the damaged zone. A classification of the main technological and operational defects is proposed, among which foreign inclusions (SiO2 or Si impurities), thinning of the generating layer, and local thermal breakdown are identified. Through numerical modeling (using finite difference and finite element methods), quantitative parameters of the detectable signal in the form of a temperature contrast on the object’s surface were established. It was shown that the magnitude of the temperature signal significantly depends on the type of defect: from fractions of a degree for local inclusions to tens of degrees in the case of thermal breakdown. The results show that the sensitivity of modern thermal imaging systems is sufficient for the reliable identification of the considered types of structural defects. It is noted that existing methods for suppressing interference can be applied to reduce the impact of interference on defect detection. Thus, the effectiveness of thermal inspection for the defect detection of solar panels with a thermogenerating layer is demonstrated. 12 Ref., 4 Fig.
Keywords: infrared thermography, solar panels, thermoelectric model, varizone semiconductors, generation defects

Received: 20.04.2026
Received in revised form: 28.05.2026
Accepted: 10.06.2026
Posted online: 30.06.2026

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Suggested Citation

ВV.O. Storozhenko, O.V. Miahkyi, R.P. Orel, S.M. Meshkov (2026) Infrared termography of solar cells with a thermogenerating layer based on varizone semiconductors. Technical Diagnostics and Non-Destructive Testing, 02, 13-16. https://doi.org/10.37434/tdnk2026.02.02