Determination of oxygen and carbon contaminations in InGaAs molecular beam epitaxy using growth interruptions

InGaAs layers were grown by molecular beam epitaxy with growth interruptions. Oxygen contamination was clearly detected by secondary ion mass spectroscopy at growth interruption interfaces. Carbon was not observed. After quantification, these measurements were extrapolated to estimate the contamination in bulk material with a very low detection limit (typically 1014 cm−2), depending on the growth interruption time. The oxygen contamination was unambiguously shown to be strongly related to the As source. A correlation was observed with the electrical properties.