Atomic Force Microscopy Studies on GaAs/In Bilayers Deposited on Si (100)

Miguel Ángel Venegas¹, Roberto Bernal- Correa², Máximo López- López¹, Álvaro Pulzara- Mora^2*

¹Departamento de Física, Centro de Investigación y de Estudios Avanzados del I.P.N., México D.F., México.
²Laboratorio de Nanoestructuras Semiconductoras, Universidad Nacional de Colombia, Manizales, Colombia.

DOI: 10.4236/mr.2015.31002                

Abstract

GaAs/In bilayers were prepared by RF Magnetron Sputtering in an Ar atmosphere on Si (100) substrates using high purity (95.95%) GaAs (100) and In targets. The growth temperatures were 300^oC and 580^oC for the high purity targets of In and GaAs, respectively. Three samples were prepared: the deposition time (td) for the GaAs layers was fixed to 30 minutes, while varied for the In layers from td = 10, 15, and 20 minutes. The morphological and optical studies of the samples were made by means of Amplitude Modulation Atomic Force Microscopy (AM-AFM). In order to analyze and correlate surface morphology and alloy composition properties, the as-prepared samples were cleaved along the [001] direction and subsequently studied by AM-AFM-micrographs. From topographic images, a statistical study of the roughness and grain size was made. Additionally, cross sectional AM-AFM-micrographs were performed for each sample, where the phase channel, which is sensitive to the material properties of the specimen, was of particular interest.

Keywords

InGaAs, Magnetron Sputtering, AFM

Conflicts of Interest

The authors declare no conflicts of interest.

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