EU PVSEC Programme Online
EU PVSEC 2021, 6 - 10 September 2021
Presentation: 2DO.10.4 Application of (Delta)n Normalised Time, (Gamma): Linear Injection-Level Dependence on LeTID and the Recovery in Crystalline Silicon
Type: Oral
Date: Thursday, 9th September 2021
17:00 - 18:30
Author(s): M. Kim, A. Ciesla, C. Sun, D. Chen, M. Abbott, B. Hallam
Presenter / Speaker: M. Kim, UNSW Australia, Sydney, Australia
Event: Conference Conference
Session: 2DO.10 Defects in Silicon and their Characterisation
Topic: 2. 1 Feedstock, Crystallisation, Wafering, Defect Engineering
Keywords: LID, Silicon Solar Cell(s), Multicrystalline Silicon, LeTID, Defects, Degradation
Summary / Abstract: The impact of the injection-level ((Delta)n) on the kinetics of light- and elevated temperature-induced degradation (LeTID) is investigated. Higher illumination intensities (I) are known to increase the LeTID and recovery rates. In this work, the (Delta)n normalisation approach is demonstrated. A similar time scale is observed after normalisation to the (Delta)n at the given I to time. The evidence suggests the recovery rate of LeTID is linearly proportional to (Delta)n and can potentially be used to predict long-term degradation, which can incorporate operating conditions and insolation level, based on an accelerated degradation testing using (Delta)n dependence. The experiment results demonstrated the difference in LeTID and the recovery trends and the overall rates. The variation of (Delta)n during the cycle leads to a slow rate during the degradation since both (Delta)n and the amount of available defect precursors are reduced. However, during the recovery, the (Delta)n is being recovered as the defect states are reduced, which appears to show compressed exponential recovery. The normalisation approach demonstrated here showed very close agreement among the results with different illumination intensities. The implication eliminated both influences due to variation of (Delta)n and the acceleration of the rate due to high n or illumination intensity.