III-V Substrates Research Articles

SIMS evaluation of contamination on ion-cleaned (100) InP substrates

Recent work has indicated that residual contamination on III-V substrates has an adverse effect on epilayer nucleation. This letter presents preliminary results of measurements of contamination levels on methanol-bromine polished ion-cleaned (100) InP substrates using low [primary ion dose (<5×1012 ions mm−2) secondary ion mass] spectrometry (SIMS). Even after ion etching ≃0.48 μ from the surface residual contamination levels in the 100-ppm range persist, the largest being oxygen. Micrographs of the ion-cleaned surface showed precipitation of In at the surface which was caused by differential sputtering effects.