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In Situ Atomic Absorption Monitoring with Substrate Reflection



S. P. Hays, Robert K. Hickernell, Kristine A. Bertness


We demonstrate a technique to apply real-time optical flux monitoring by in situ atomic absorption when the only available optical path through a molecular beam epitaxial growth chamber reflects from the substrate. Thin-film interference effects in the reflected signal were virtually eliminated during growth by using a collinear beam that has a wavelength very close to that of the group-III absorption line. This method enables atomic absorption monitoring to be applied to heterostructure growths without the need for real-time reflectance analysis. We demonstrated the technique by monitoring Ga flux during GaAs growth using a Mn lamp for the off-resonance source. The short-term uncertainty in the flux measurement was 0.6% (one standard deviation). Theroetical calculations indicated that approximately 0.2% and 0.3% maximum instantaneous error can be attained for Ga and Al, respectively, during the growth of vertical cavity surface emitting lasers.
Proceedings Title
Proc., SPIE, Vertical-Cavity Surface-Emitting Lasers IV
Conference Dates
January 24-28, 2000
Conference Location
San Jose, CA


atomic absorption, optical flux monitoring, in situ, MBE, VCSEL


Hays, S. , Hickernell, R. and Bertness, K. (2000), In Situ Atomic Absorption Monitoring with Substrate Reflection, Proc., SPIE, Vertical-Cavity Surface-Emitting Lasers IV, San Jose, CA (Accessed June 24, 2024)


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Created December 31, 1999, Updated October 12, 2021