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Hall-effect data between 4 and 300 K on p-type strained quantum well structures in the InGaAs alloy system show pronounced effects due to the strain-induced splitting of the heavy- and light-hole valence bands. As a function of biaxial compression in the range 0.5–1.4%, the 77 K mobilities increase monotonically by a factor of ∼5, as does a high-temperature activation energy which is found to be nearly equal to the predicted strain splitting. [ABSTRACT FROM AUTHOR]

We report the use of wavelength-modulated photocurrent spectroscopy to obtain detailed information on quantum well transitions in an In0.14Ga0.86As/GaAs strained-layer superlattice. The spectra are interpreted in terms of a Kronig–Penney model with literature values for offsets and deformation potentials. The effect of the test structure’s built-in electric field must be included to obtain agreement with this theory. [ABSTRACT FROM AUTHOR]

We investigate the ability of semiconductor superlattices to filter or block threading dislocations by growing and studying structural properties of superlattices composed of alternating layers (∼100 Å each) of InxGa1-xAs and InyAl1-yAs. These superlattices were grown with x=y corresponding to lattice-matched compositions such that the layers have minimal strain, and x≠y corresponding to lattice-mismatched compositions such that the layers have large coherent strains. By correlating the number of dislocations observed in optical images of the superlattices, with the amount of layer strain determined by x-ray double diffraction analysis, we investigate the effect of strain on the filtering ability. We find that both types of superlattices are effective in filtering dislocations. [ABSTRACT FROM AUTHOR]

The two-dimensional, strain-induced light-hole masses in InGaAs strained-layer superlattices are shown to have large nonparabolicity contributions. Calculated hole masses agree with experimental values to within the 20% scatter. The results indicate that these tailorable hole masses could be useful tools for studying two-dimensional valence transport. [ABSTRACT FROM AUTHOR]

We have characterized (InGa)As/GaAs strained-layer superlattices (SLS’s) that have been implanted with 300 keV argon ions at room temperature for fluences sufficient to induce precipitous stress relief in the implanted composite. SLS compositional modulation is lost due to ion beam mixing over much of the ion range; however, the implanted regions remain crystalline despite extensive damage near the mean ion range. High-density dislocation networks are found near the substrate-buffer interface after precipitous stress relief and are correlated with the occurrence of the effect. [ABSTRACT FROM AUTHOR]

We have characterized damage production in both (InGa)As/GaAs and Ga(AsP)/GaP strained-layer superlattices (SLS’s) for fluences sufficient to induce compositional disordering at three different implant temperatures. Dramatically different implant temperatures are required to produce similar defect distributions between the two SLS systems. Implants at lower temperatures [80 K for the (InGa)As/GaAs system, 300 K and below for the Ga(AsP)/GaP system] exhibit amorphous zones at depths consistent with the predictions of ion range codes; while implants at elevated temperatures [25 °C in (InGa)As/GaAs, 400 °C in the Ga(AsP)/GaP system] exhibit greatly reduced damage levels characterized mainly by extended defects. [ABSTRACT FROM AUTHOR]