OPTICAL LUMINESCENCE YIELD X-RAY-ABSORPTION FINE-STRUCTURES AT THE SULFUR AND SILICON K-EDGE

Optical luminescence induced by soft x-ray excitation in the vicinity of the S K-edge (approximately 2472 eV) and Si K-edge (approximately 1 839 eV) in P-31 (ZnS:Cu phosphor) and porous silicon has been studied with an optical spectrometer. The luminescence yield was in turn used, together with total electron yield, to record x-ray absorption fine s tructures in the near edge region of the corresponding S and Si K-edge . It is found that although the luminescence spectrum of soft x-ray ex cited P-31 above and below the S K-edge is identical, a small shift is noted in porous silicon at photon energies below and above the Si K-e dge and that the luminescence yield (optical photon/soft x-ray photon absorbed) varies significantly depending on experimental conditions an d/or the nature of the exciting channel.