Abstract
We investigated the effect of Mg p- and Te/Si n-type doping on the in-situ reflectance anisotropy (RAS) spectra for the material system AlGaInP. All results have been compared to ex-situ performed Hall abd SIMS measurements. RAS intensities of Mg-doped AlInP first increase with increasing Mg-flux and then decrease even below the level of the undoped spectra. We explain by the effect, that beyond a critical Mg-flux the excess Mg remains on the surface and causes roughening of the surface and decreasing of the RAS intensities. For the n-type dopants we found a very different impact on the RAS data for Te doping than for Si doping. The RAS intensities from the Si-doped layers show a linear dependence versus the logarithm of the free carrier concentration. The RA spectra of Te-doped samples show a significant change in the shape of the spectra, which is related to surfactant effect of tellurium accumulating on the surface. Besides this a clear dependence of the RA-features to the free carrier concentration was found.
Original language | English (US) |
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Pages (from-to) | 4727-4730 |
Number of pages | 4 |
Journal | Journal of Crystal Growth |
Volume | 310 |
Issue number | 23 |
DOIs | |
State | Published - Nov 15 2008 |
Keywords
- A1. Doping
- A1. Reflectance anisotropy spectroscopy
- A3. Metalorganic vapor phase epitaxy
- B1. AlGaInP
- B2. Semiconducting quaternary alloys
ASJC Scopus subject areas
- Condensed Matter Physics
- Inorganic Chemistry
- Materials Chemistry