VISIBLE-LIGHT EMISSION AT ROOM-TEMPERATURE FROM PECVD A-SI-H-O

We report in this paper the observation of visible photoluminescence at room temperature from a-Si:H:O films prepared by the conventional PECVD technique at two kinds of process: a normal and an alternation of hydrogen plasma treatment and deposition. It has been discovered that the PL intensity of the films from the alternating mode is about ten times stronger than that from the normal one. Infrared absorption spectroscopy revealed that the concentration of oxygen rather than hydrogen was increased by H-2 plasma treatment. The enhancement of PL could be associated with the addition of the characteristic oxygen-related configuration as partially oxidized (SiH2)(x) or Sill.