INFRARED CHARACTERIZATION OF HOT-SPOTS IN SOLAR-CELLS WITH HIGH-PRECISION DUE TO SIGNAL TREATMENT PROCESSING

In this paper we show how to improve greatly the resolution of IR ther mography by using two different signal treatment methods: a static tre atment and a dynamical treatment. This signal processing allows the st udy of 100 cm(2) cells under low-forward or reverse-polarization condi tions. Static and dynamical methods have both good resolutions: static has the advantage of being fast, and dynamical method does not need a ny reference image nor cooling system. We have shown that IR thermogra phy is an interesting method for investigating shunts in solar cells. Thermal maps and I-V characterization of the hot spots show that the o rigin and the behavior of the shunts are varied and their influence on the efficiency is probably more important than what is usually though t. (C) 1998 Elsevier Science B.V. All rights reserved.