Photoluminescence degradation in porous silicon upon annealing at high temperature in vacuum

Abstract

lPhotoluminescent p-type porous silicon (PS), which showed a strong photoluminescence (PL) peak centered at about 720 nm, was annealed in vacuum. After the PS was annealed at about 550 degreesC, the PL completely quenched, and it was found that the average skeleton size of the PS layer became 50 similar to 100 nm, which was 5 similar to 10 times larger than that of PS before annealing. The Si 2p cote level photoemission spectrum showed that the amount of oxide increased with annealing temperature. The increase in the average skeleton size, rather than a change in the oxide states, seemed to be the main cause of the observed irrecoverable PL degradation.