How methanol affects the surface of blue and red emitting porous silicon

The Si-H_x species on the surface of the red emitting samples were reported to be accountable for the chemical sensitivity of the material. Moreover, when all of the Si-H was desorbed from the red emitting sample and a stable oxide was developed, the sample became insensitive to the environment. In addition, the sensitivity of the blue emitting oxygen passivated sample was analyzed. The surprising sensitivity of the blue emitting oxygen passivated sample was accredited to the modification of current traps due to solvent exposure. This behavior was consistent with the model which attributed the blue photoluminescence to existing traps.