Theory of Semiconducting Superlattices and Microstructures
Abstract
This final report summarizes theoretical work on semi conducting superlattices and microstructures. A focus of the work is a fundamental understanding of deep-level structures of impurities in semiconductors. Probably the most striking results in this area concern IV-VI semiconductors such as PbTe and SnTe, where we have originated the concept of false valence: In on a Te site in SnTe is a (triple) acceptor and has normal valence of -3 with respect to Te. But on a Te site in PbTe, In is a (triple) donor with a false valence of +3 with respect to Te because an In deep p-like one-electron level capable of trapping six electrons crosses the gap as x decreases in Pbl-xSnxTe. This theory predicts that In is a donor in PbTe but an acceptor in SnTe; it argues that in IV-VI semiconductors impurities often occupy the intuitively wrong site or antisite; it shows that the relevant In occupies Te sites; it explains low doping efficiencies; and it shows promise for explaining solidus curves. This work on InN illustrates how our theory can be useful for the fabrication and doping of new electronic materials. The recent development of high-mobility InN raises the possibility of making UV sensors and even lasers out of this material. We have presented global predictions on the behavior of s- and p-bonded deep levels in InN, Inl-xGaxN, and Inl-xA xN as a means of guiding experiments aimed at doping these materials for use in UV and glue-green optical devices. Semiconductor theory, Superlattices, Deep level structures IV-VI compounds, PbTe, SnTe, HEMT Structures, local-density theory.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1992
- Accession Number
- ADA248681
Entities
People
- John D. Dow
Organizations
- University of Notre Dame