Photo-μSR a new method for studying photovoltaics
01 Jul 2022



Researchers use a new method to separate the bulk and surface recombination of silicon photovoltaic cells.




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​Charge carrier kinetics, especially their lifetime, ultimately determine the performance of silicon photovoltaic cells. With a thin layer of silicon, where carriers are generated by sunlight, it is important to control and understand their (unwanted) recombination not only at bulk but also at the surface. Howe​​​ver, decoupling these is challenging using laboratory characterisation techniques.

A new method of photoexcited muon spin relaxation (photo-μSR) has been developed and, in this study, used to separate the bulk and surface​ recombination. Because the muons can be implanted at different depths within a Si wafer, the carrier lifetime spectrum can be measured at specific points. This enabled the researchers to use a simple model to separate the bulk and surface contributions. This technique could be extended to a range of other semiconductor systems, including power electronic devices. 

Further Information:

Related publication: Decoupling bulk and surface recombination properties in silicon by depth-dependent carrier lifetime measurements, Appl. Phys. Lett., 118, 252105 (2021) DOI: 10.1063/5.0054291

Contact: Burke, Katie (STFC,RAL,ISIS)