Minority carrier lifetime is a very important parameter for optoelectronic materials used for different photonic devices, such as solar cells or light emitting diode. It is observed that both the photo-current transient and time resolved photo-luminescence (TRPL) have been used to determine the said parameter.
My inquiry is which one is more accurate? Is there any effect (perturbation) of applied bias/ metal contact in case of transient photo-current process while measuring the minority carrier lifetime?
Which factors (and why) lured people to use contactless TRPL to calculate the same parameter?
I am not sure if minority carrier lifetimes can be extracted using Transient Photo-current. It is more like charge extraction study on the full device and may be influenced by several other factors. Can you share any such studies ?
Hello Harikesh,
Well, there are instances where people have used Photo Conductivity Decay (PCD) or microwave detected photo conductivity (MPD) to measure the recombination lifetime of thin film semiconductors, even in case of halide perovskite.
If one considers low level injection, the SRH recombination dominates over others, and under this condition the normalized photo-conductivity decay provides with the minority carrier lifetime. To minimize the effect of trap assisted emission and band-to-band recombination, 25% of the top and bottom of the photo-conductivity decay curve is being ignored.
I think in the past people used mainly PC transients (see e.g. Ryvkin, S. M., 1964, Photoelectric effects in semiconductors. New York, Consultants Bureau.) because it was simpler. Later, when good apparatus for TRPL became available, people uses TRPL taking advantage of the non-contact measurements.
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