Effect of V/III ratio on the optical properties of (3 1 1)A and (3 1 1) B oriented InAlAs/InP heterostructures

Power- and temperature-dependent photoluminescence investigation of carrier localization at inverted interface transitions in InAlAs/InP structures

“…8,17) The origin of these peaks has been presented elsewhere in detail. 8,9) We note that the different energy observed between the transitions of type II corresponds to the difference in the arsenic diffusion at the inverse interface and the PZ field.…”

“…The red PL peaks at higher energy are due to the interfacial defects in InAlAs/InP, whereas the green PL peak energies are associated with the type-II PL transition. 8,9,16) The line width broadening for these peaks can be explained by the non-uniformity of the alloy composition caused by the clustering due to the imperfect incorporation of the Al cations. 4) Then the difference between the FWHM may be due to the dependence of alloy composition fluctuation on the growth conditions such as the V/III flux ratio.…”

“…3,7,8) To overcome these problems, deposition on high-index substrates such as (311)A/B enables the formation of an inverted interface of better optical quality on InP substrates. 8,9) The surface polarity [A: indium (In) face or B: phosphorus (P) face] is one of the most important parameters in determining the quality of the inverted interface (InP/InAlAs). 8,9) Growth on high-index substrates (N11) offers a number of special properties in comparison to those grown on InP (100), such as the presence of a piezoelectric (PZ) field, substrate polarity and the difference in chemical potentials in surfaces.…”

“…8,9) The surface polarity [A: indium (In) face or B: phosphorus (P) face] is one of the most important parameters in determining the quality of the inverted interface (InP/InAlAs). 8,9) Growth on high-index substrates (N11) offers a number of special properties in comparison to those grown on InP (100), such as the presence of a piezoelectric (PZ) field, substrate polarity and the difference in chemical potentials in surfaces. 8,10,11) However, a non-optimized substrate orientation causes the formation of high concentrations of defect points and alloy phase separation which deteriorate the structural and optical properties.…”

“…4) Besides optimizing the substrate orientation, it is also necessary to establish control and to understand the effect of the arsenic overpressure (V/III flux ratio with fixedflow group III sources) on the quality of the inverted interface (InP on InAlAs). 4,5,9) In this context, Sayari et al 5) carried out a Raman study of the V/III flux ratio effect in In x Al 1-x As/InP heterostructures. The study shows that the In x Al 1-x As layers grown on (100) Fe-doped InP are extremely sensitive to the V/III flux ratio.…”