Effects of N₂, O₂, and H₂O on GaAs passivated by photowashing or coating with Na₂S⊙9H₂O

The photoluminescence (PL) from the surface region of GaAs passivated by photowashing or coating with Na2S⊙9H2O is shown to be sensitive to the gas ambient. Both water vapor and oxygen must be present in order to obtain a large PL signal. The effects are activated by the measuring laser light.