Grain size dependent optical band gap of CdI2 films

Bulletin of materials science

Pankaj Tyagi¹  A G Vedeshwar¹ 

[1] Department of Physics and Astrophysics, University of Delhi, Delhi 110 007, India$$Department of Physics and Astrophysics, University of Delhi, Delhi 110 007, IndiaDepartment of Physics and Astrophysics, University of Delhi, Delhi 110 007, India$$

关键词: Optical properties;    thin films;    halides.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

The thermally evaporated stoichiometric CdI₂ films show good ð‘�?-axis alignment normal to substrate plane for film thickness up to 200 nm. The optical absorption data indicate an allowed direct interband transition across a gap of 3.6 eV in confirmation with earlier band structure calculations. However, part of the absorption data near band edge can be fitted to an indirect band gap of 3 eV. The dependence of band gap on film thickness (> 200 nm) can be explained qualitatively in terms of decreasing grain boundary barrier height with grain size.

【 授权许可】

Unknown