ROOM-TEMPERATURE PHOTOLUMINESCENCE OF PHOTOELECTROCHEMICALLY ETCHED N-TYPE SI

n-type Si was anodized (photoelectrochemically etched) in 5% HF solution under white light illumination. This surface treatment yielded a porous layer which emitted light at room temperature upon excitation with an Ar ion laser. The influence of various experimental parameters on the light emission of the porous silicon has been studied. For example, it was found that the photoluminescence of the lightly doped Si is blue-shifted compared with the heavily doped Si. The luminescence of the PEC etched Si could be correlated with the formation of a nanoporous film on a macroporous Si layer. It is believed that this luminescence is associated with quantum confinement within this nanoporous film.