Abstract Porous silicon samples were prepared for optical studies by using the photoluminescence (PL), Raman scattering (RS), as well as the absolute reflectance and ellipsometry methods. Results show that the porous Si has low optic constants, and can trap the visible photons of more than 95%, but give no evidence of a strong interband transition existing in the vis-ible region. The Bruggeman effective-medium-approximation (EMA) and Lorentz oscillator models were used in data analyses. Calculations show that the layer dispersion effect may result in a red shift of the PL peak. The possible mechanism for the PL and Raman enhance-ment as well as the photon trap phenomenon was discussed, and was attributed mainly to the random multiple micro-reflections in the porous-Si layer having extremely large internal micro-Burfaces.
Received: 26 July 1993
Accepted manuscript online:
Fund: Project supported by the State Education Commission, the State Science and Technology Commission, and the National Natural Science Foundation of China.
Cite this article:
CHEN LIANG-YAO (陈良尧), HOU XIAO-YUAN (侯晓远), HUANG DA-MING (黄大鸣), ZHANG FU-LONG (张甫龙), FENG XING-WEI (冯星伟), YANG MIN (杨敏), SU YI (苏毅), QIAN YOU-HUA (钱佑华), WANG XUN (王迅) STUDY OF PHOTON-TRAPPING PHENOMENON IN POROUS SILICON LAYER 1994 Acta Physica Sinica (Overseas Edition) 3 595
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.