The influence of quantum well and barrier thicknesses on photoluminescence spectra of InGaAs/AlInAs superlattices grown by LP-MOVPE

Abstract

In the presented work, the influence of the quantum well and barrier thicknesses on optical characteristics of InGaAs/AlInAs superlattices was reported. Six different structures of In0.53Ga0.47As/Al0.48In0.52As superlattices lattice-matched to InP were grown by low pressure metal organic vapour phase epitaxy (LP-MOVPE). Optical properties of the obtained structures were examined by means of photoluminescence spectroscopy. This technique allows quick, simple and non-destructive measurements of radiative optical transitions in different semiconductor heterostructures. The analysis of recorded photoluminescence spectra revealed the influence of the quantum well and barrier thicknesses on the emission line energy.

Gradual Degradation of InGaAs LEDs: Impact on Non-Radiative Lifetime and Extraction of Defect Characteristics

“…Generally speaking, a higher leakage current, if not related to a parallel resistance component, can be associated with an increased concentration of defects in proximity of the junction, possibly indicating an increased defectiveness of group C devices compared to shorter wavelength LEDs. Assuming that tuning of the emission wavelength was achieved through compositional variations rather than through QW width adjustments [ 16 ], this may be ascribed to the higher indium content in the semiconductor alloy, that may favor higher defectiveness and the conduction mechanisms, such as trap-assisted tunneling, that typically dominate in the low forward bias regime [ 17 , 18 ]. The higher defectiveness of group C devices was also confirmed by the analysis of the bias-dependent ideality factor, reported here for a representative sample of each group in Figure 1 c. The experimental data show that even in an unaged state, LEDs belonging to group C exhibit a higher ideality factor, with values close to 2 at 0.45 V. An ideality factor close to 2 typically indicates a conduction regime dominated by defect-related recombination currents within the space-charge region of the device; therefore, this finding further suggests that group C devices are affected by a higher concentration of defects in the proximity of, or within, their active region.…”

Influence of Fröhlich Interaction on Intersubband Transitions of InGaAs/InAlAs-Based Quantum Cascade Detector Structures Investigated by Infrared Modulated Photoluminescence

“…Up to date, however, there has been no prior report on characterization of QCDs, except for QWs or superlattices. [25][26][27] The reasons may be that (i) the conventional PL measurement is limited to visible and near-infrared regions, for which wavelengths are shorter than the typical wavelengths associated with QCD subband transitions, (ii) the radiative recombination efficiency of the intraband transitions is usually much lower than that of interband transitions, and (iii) the subband PL of the QCD structure has special requirements regarding geometric configuration.…”