Paper: Identifying the Real Minority Carrier Lifetime in Nonideal Semiconductors: A Case Study of Kesterite Materials

Title: Identifying the Real Minority Carrier Lifetime in Nonideal Semiconductors: A Case Study of Kesterite Materials Authors: Charles J. Hages,* Alex Redinger, Sergiu Levcenko, Hannes Hempel, Mark J. Koeper, Rakesh Agrawal, Dieter Greiner, Christian A. Kaufmann, and Thomas Unold* Link: Adv. Energy Mater. 2017, 1700167 (Cited by 16) Abstract: Time‐resolved photoluminescence (TRPL) is a powerful characterization technique to study carrier dynamics and quantify absorber quality in semiconductors. The minority carrier lifetime, which is critically important for high‐performance solar cells, is often derived from TRPL analysis. However, here it is shown that various nonideal absorber properties can dominate the TRPL signal making reliable extraction of…

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Video: Analysis of techniques for measuring carrier recombination lifetime

Author:  Dr. Richard K. Ahrenkiel is a Research Professor of Metallurgical and Materials Engineering at the Colorado School of Mines in Golden, Colorado. Abstract Rapid, accurate and contactless measurement of the recombination lifetime is a very important activity in photovoltaics. The excess carrier lifetime (Δn(t)) is the most critical and variable parameter in the development of photovoltaic materials. Device performance can be accurately predicted from the lifetime measurement of the starting material. However, there is no single measurement that directly measures the bulk lifetime as all measurements are based on a device model. A primary issue is that the lifetime is…

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Paper: Complex Interplay between Absorber Composition and Alkali Doping in High-Efficiency Kesterite Solar Cells

Title: Complex Interplay between Absorber Composition and Alkali Doping in High-Efficiency Kesterite Solar Cells Authors: Stefan G. Haass,* Christian Andres, Renato Figi, Claudia Schreiner, Melanie Bürki, Yaroslav E. Romanyuk, and Ayodhya N. Tiwari Link (Open Acess): Adv. Energy Mater. 2018, 8, 1701760 Abstract: Sodium treatment of kesterite layers is a widely used and efficient method to boost solar cell efficiency. However, first experiments employing other alkali elements cause confusion as reported results contradict each other. In this comprehensive investigation, the effects of absorber composition, alkali element, and concentration on optoelectronic properties and device performance are investigated. Experimental results show that in the row…

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