S. Brückner, A. Maaßdorf, M. Weyers
J. Cryst. Growth, vol. 590, art. 126696 (2022).
Metalorganic vapor phase epitaxy growth of red emitting laser structures based on (AlGa)1-xInxP (AlGaInP) compounds requires thorough control of In incorporation during growth of AlGaInP layers which heavily depends on growth parameters and reactor state. We established an in situ method to determine the In incorporation in AlGaInP layers during growth without any prior calibration based on ex situ characterization. This requires to model the lattice constants of substrate and growing layer and feed it with the in situ measured wafer temperature, growth rate and wafer curvature. The model makes use of the Stoney equation and Vegard’s law to calculate the In content of AlGaInP layers grown on GaAs substrates. Correlation of in situ results to ex situ results from X-ray diffraction confirmed the accuracy of our method. Our in situ method allowed us to study the influence of dopants on growth of AlGaInP layers. At high temperature Si doping from Si2H6 showed no influence on the In incorporation during growth, however, Zn doping from DMZn showed strong impact on In incorporation and growth rate. In particular, increasing the DMZn/III ratio during AlGaInP growth linearly decreases In incorporation and growth rate. Accordingly, the presence of Zn on the growth surface hinders In incorporation and causes enhanced In re-evaporation from the surface at high temperatures.
Ferdinand-Braun-Institut (FBH), Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany
A1 Characterization; A3 Metalorganic vapor phase epitaxy; B1 Phosphides; B2 Semiconducting III-V materials; B3 Laser diodes,; B3 Light emitting diodes
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