
A new technique of surface passivation of silicon substrates by quinhydrone/ethanol treatment has been investigated. To estimate the surface passivation effect, the lifetimes of the silicon substrates were measured using the microwave photoconductive decay method. The measured lifetimes were dependent on quinhydrone concentration and passivation time. The 0.01 mol/dm3 quinhydrone/ethanol treatment showed a good passivation effect, and a very low surface recombination velocity was obtained. The quinhydrone/ethanol treatment was a more effective passivation technique than the iodine/ethanol treatment. Therefore, the quinhydrone/ethanol passivation can be widely used for lifetime measurement.