Theory of below gap absorption bands in n-type SiC polytypes; Or, how SiC got its colors

Walter R L Lambrecht, Sukit Limpijumnong, Sergey Rashkeev, Benjamin Segall

Research output: Chapter in Book/Report/Conference proceedingChapter

2 Citations (Scopus)

Abstract

Optical absorption bands below the band gap in n-type SiC are discussed in the framework of first-principles band structure calculations. While the peak positions and their polarization are well reproduced in a pure band-to-band model, the widths of the spectra obtained for samples with high impurity concentrations indicate a significant role of the band tailing due to the N-impurities. This leads to a partial breakdown of the vertical selection rule, which we take into account by means of a density of states calculation over a limited region of k-space, and a weaker breakdown of symmetry selection rules. Differences for samples with low concentration of dopants and the possibility of impurity resonances in the continuum are discussed.

Original languageEnglish
Title of host publicationMaterials Science Forum
PublisherTrans Tech Publ Ltd
Volume338
Publication statusPublished - 2000
Externally publishedYes
EventICSCRM '99: The International Conference on Silicon Carbide and Related Materials - Research Triangle Park, NC, USA
Duration: 10 Oct 199915 Oct 1999

Other

OtherICSCRM '99: The International Conference on Silicon Carbide and Related Materials
CityResearch Triangle Park, NC, USA
Period10/10/9915/10/99

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ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Lambrecht, W. R. L., Limpijumnong, S., Rashkeev, S., & Segall, B. (2000). Theory of below gap absorption bands in n-type SiC polytypes; Or, how SiC got its colors. In Materials Science Forum (Vol. 338). Trans Tech Publ Ltd.