X-ray photoelectron spectroscopy characterization of stain-etched luminescent porous silicon films

The surface and in-depth chemical nature of the photoluminescent stained Si layer obtained with a novel procedure based on HF/HNO3 is presented. Oxide -free porous Si surfaces result from controlled preparation, storing and ha ndling of samples, as revealed by parallel X-ray photoelectron spectroscopy and X-ray-induced Anger electron spectroscopy measurements, coupled with A r+ ion sputtering. The present findings support the model for the porous la yer of oxidized samples of Si grains embedded in a silica gel matrix. (C) 1 999 Published by Elsevier Science B.V. All rights reserved.