The influence of ion mass and dose on the intermixing of GaAs/GaAlAs quantum-well structures using photoluminescence (PL) and secondary-ion-mass spectroscopy (SIMS) techniques has been studied. Ga, Zn, Ar, Mg, Ne, and He ions are implanted in a single-quantum-well (SQW) structure at different doses. After annealing, the amount of intermixing between Al and Ga is extracted from the PL peak energy shift of the near-band-gap emission of the SQW. The measured Al diffusion length values ΔAl for different ion species agree with a simple model which assumes that the implantation damage in conjunction with low T (T<600 °C) defect diffusion is responsible for the mixing. We observe a similar dose dependence for ΔAl for all the above ions. For high implantation doses we have studied the mixing by Ar ions after implantation and annealing with SIMS. The SIMS data indicate that at high doses collisional mixing is the dominant mechanism for the disordering. Drastic mixing effects are obtained in the above quantum-well structures after high-temperature annealing of samples implanted with electrically active impurities (S,Si).

Highly doped InP:Yb layers have been grown by adduct metalorganic vapor phase epitaxy at atmospheric pressure. Yb(MeCp)3, where Me=CH3 and Cp=n5-C5H5, was synthesized as Yb source material because of its relatively high vapor pressure at acceptable source temperatures. The layers were grown in a wide range of growth temperatures (560–670 °C) and Yb mole fractions (10−9–10−7). In photoluminescence experiments they showed strong Yb3+-4f emission. The layers were further characterized by Hall measurements and secondary-ion mass spectroscopy. In order to obtain n-type InP:Yb samples with high carrier concentrations we have grown InP layers double doped with S and Yb.

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We have produced beveled cross-sections of GaAs/GaAlAs multiple quantum well structures with inclination angles of 0.55 minutes of arc with a special ion beam etching technique. The extension of the damage which is induced during the dry etching process can be evaluated directly by a comparison of spatially resolved secondary ion mass spectroscopy and photoluminescence measurements. We observe a thickness of the damaged surface layer between 36 nm for 250 eV Argon ions and 160 nm for 1000 eV Argon ions in a GaAs/GaAlAs multiple quantum well structure.