Dislocation filtering by interfaces between AlxIn1−xSb and AlyIn1−ySb layers grown on a GaAs (001) substrate has been investigated. Transmission electron microscopy analysis shows that as many as 59% of threading dislocations (TDs) can be eliminated by such an interface. An interlayer sample that contains six Al0.12In0.88Sb∕Al0.24In0.76Sb interfaces has 6.0×108TDs∕cm2 at 1.6μm thickness. Compared with an Al0.12In0.88Sb epilayer without an interlayer, this TD density is a factor of ∼4 lower for the same thickness, and about the same as for a layer that is more than twice as thick. Our results suggest that AlxIn1−xSb∕AlyIn1−ySb interfaces can be used to improve the performance of any InSb-based device in which AlxIn1−xSb is used as a buffer, insulating, or barrier layer material.

The effect of structural defects on electron mobilities has been investigated in InSb quantum wells (QWs) grown on GaAs (001) substrates. The usefulness of a ⟨116⟩-directional transmission electron microscopy analysis for microtwins (MTs) in a plan-view specimen is demonstrated. MTs and threading dislocations reduce the room-temperature (RT) electron mobility in InSb QWs. It is found that the use of 2° off-axis GaAs (001) substrates is effective in reducing MT densities in InSb QWs. The electron mobility in InSb QW at RT, 4.0×104cm2∕Vs with an electron density of 4.6×1011∕cm2, is among the highest values reported in semiconductor QWs.

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High-k/InAs interfaces have been manufactured using InAs surface oxygen termination and low temperature atomic layer deposition of HfO2. Capacitance–voltage (C–V) curves revert to essentially classical shape revealing mobile carrier response in accumulation and depletion, hole inversion is observed, and predicted minority carrier response frequency in the hundred kHz range is experimentally confirmed; reference samples using conventional techniques show a trap dominated capacitance response. C–V curves have been fitted using advanced models including nonparabolicity and Fermi-Dirac distribution. For an equivalent oxide thickness of 1.3 nm, an interface state density Dit = 2.2 × 1011 cm−2 eV−1 has been obtained throughout the InAs bandgap.

Double heterostructures (DH) were produced consisting of a CdTe film between two wide band gap barriers of CdMgTe alloy. A combined method was developed to quantify radiative and non-radiative recombination rates by examining the dependence of photoluminescence (PL) on both excitation intensity and time. The measured PL characteristics, and the interface state density extracted by modeling, indicate that the radiative efficiency of CdMgTe/CdTe DHs is comparable to that of AlGaAs/GaAs DHs, with interface state densities in the low 1010 cm−2 and carrier lifetimes as long as 240 ns. The radiative recombination coefficient of CdTe is found to be near 10−10 cm3s−1. CdTe film growth on bulk CdTe substrates resulted in a homoepitaxial interface layer with a high non-radiative recombination rate.