One of the advantages of the MBE growth process is its compatibility with a variety of in-situ monitoring and control techniques. In addition to the most extended RHEED technique, optical techniques can be easily implemented through appropriate windows of the UHV system providing relevant complementary information on the growth front.
Some of these techniques are standard such as IR pyrometry and spectral reflectivity measurements. In this talk, we will refer only to some less extended but very useful techniques that have been implemented in our laboratory in a simple and practical way: Reflectance Anisotropy (RA), Laser Light Scattering (LLS) and Laser Deflection Stress Monitoring (LDSM). Description of the principles and experimental set-ups will be followed by examples of application to various growth processes, in particular:
- Controlling stoichiometry of low temperature InP growth using RA
- InAs/InP Quantum Wire self-assembling monitoring by LDSM
- In segregation effects during InAs/GaAs QDs formation and capping
- Surface roughness control during growth of relaxed InGaAs/GaAs layers by LLS and LDSM
References:
1.A new in situ III-V surface characterization technique: chemical modulation spectroscopy, P.A.Postigo, T.Utzmeier, G.Armelles and F.Briones. Journal of Crystal Growth, 175(1997) 298-303
2.In situ observation of related surface stress during molecular beam epitaxy (MBE) growth of III-V compounds, J.P.Silveira and F.Briones. Journal of Crystal Growth 201/202 (1999) 113-117
3.Electrical and optical properties of Be doped InP grown at low temperature by solid source atomic layer molecular beam epitaxy, P.A.Postigo, M.L.Dotor, P.Huertas, F.García, D.Golmayo and F.Briones. Journal of Applied Physics 85 (9) (1999) 6567-6570
4.Surface stress effects during MBE growth of III-V semiconductor nanostructures
J.P.Silveira, J.M.García, F.Briones Journal of Crystal Growth, 227/228 (2001) 995- 999
5.A growth method to obtain flat and relaxed In0.2Ga0.8As on GaAs (001) eveloped through in-situ monitoring of surface topography and stress evolution, M. U. González, Y. González, L. González, M. Calleja, J.P. Silveira, J.M. García, y F. Briones. Journal of Crystal Growth , 227/228, (2001) 36-40.
7. InAs/InP (001) quantum wire formation due to anisotropic stress relaxation: in situ stress measurements,J.M. García, L. González, M.U. González, J.P. Silveira, Y. González, y F. Briones, Journal of Crystal Growth 227/228 (2001). 975-979.
8.In situ measurements of As/P exchange during InAs/InP(001) quantum wires growth, M.U. González, J.M. García, L. González, J.P. Silveira, Y. González, L.D. Gómez, F. Briones.Applied Surface Science 188,188-192 (2002).
8. Limited In incorporation during pseudomorphic InAs/GaAs growth and QD formation observed by in-situ stress measurements, J.P.Silveira, J.M.Garcia and F.Briones, Appl.Surf.Science, 188, 75-79 (2002)
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