Commercial claims for LED-based products in terms of lumen maintenance are fully based on TM-21 extrapolations using LM-80 data. This paper indicates that there may be a risk in doing this as TM-21 only relies on the behavior of the average LED degradation, instead of taking into account the degradation of all individual LEDs. Therefore, we propose a more profound statistical analysis in order to make the appropriate step from TM-21 extrapolation to lumen maintenance on a product level. This is needed as some commercial claims are based on 10 years of warranty and some service bids provide periods of 20 to 25 years of operation. This paper reviews the different approaches currently available to perform lumen maintenance extrapolations. We propose a new method to analyze and extrapolate LM-80 data using a more profound statistical approach. Highlights The main highlights of the presented research are: • A new statistical method to extrapolate LM-80 data • The method outperforms the currently available ones as it is statistically founded • Five cases were executed and benchmarked with the TM-21 method • A full statistical acceleration model is now available for lifetime assessment of LEDs

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Homogeneous thin films of zinc titanate have been successfully prepared on Si(100) wafers by depositing a film of zinc and titanium oxides (ZnO‐TiO2) by low‐pressure metalorganic chemical vapor deposition (MOCVD), followed by an annealing treatment. The precursors used for the deposition were diethylzinc (DEZ), tetraisopropoxide titanium (TPT), and water. By performing the deposition at temperatures between 140 and 350C, the stoichiometry of the as‐deposited films could be effectively controlled over Zn/Ti ratios between 0.5 and 2.5, which cover the composition of various zinc titanate phases identified in the literature. The as‐deposited ZnO‐TiO2 films are amorphous, and possess a fairly smooth surface. XPS and SIMS analysis showed that the composition of these films is uniform over the wafer as well as through the films bulk. An annealing treatment of the as‐deposited films at high temperature