Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Combination of selective etching and AFM imaging for the thickness analysis of AlGaAs/GaAs heterostructures

Kombination von selektivem Ätzen und AFM zur Schichtdickenanalyse von AlGaAs/GaAs Heterostrukturen
: Müller, S.; Weyer, J.L.; Köhler, K.; Jantz, W.; Frigeri, C.

Woo, J.C.; Park, Y.S.:
Compound Semiconductors 1995. Proceedings of the Twenty-Second International Symposium on Compound Semiconductors
Bristol: IOP Publishing, 1996 (Institute of Physics - Conference Series 145)
ISBN: 0-7503-0342-5
International Symposium on Compound Semiconductors <22, 1995, Cheju Island>
Fraunhofer IAF ()
AFM; DSL; heterostructure; Heterostruktur; layer thickness; Schichtdickenanalyse; selective etching; selektives Ätzen

The vertical structure of AlGaAs/GaAs epitaxial layer systems for micro- and optoelectronic device fabrication has been studied by selective etching combined with AFM imaging. Dark etching and photoetching with Cr03-HF-H20 solutions were used to transform composition and doping variations into height differences of the cleaved (110) surface. The etching parameters (time, composition and supply of carriers by illumination) were optimized for accurate thickness determination by AFM. The measurements were corroborated by comparison with cross-sectional TEM mapping. The dependence of the etching rate on the composition and the occurence of small, but measurable height variations without any etching is discussed.