Dependence of indium incorporation upon the substrate misorientation during growth of In x Ga 1 − x As by metalorganic vapour phase epitaxy

Abstract

The incorporation of indium during growth of InxGa ~ _xAS (with x < 5 × 10 -3) by metalorganic vapour phase epitaxy on GaAs substrates with orientations vicinal to (100) has been studied as a function of the growth temperature, the input mole fraction of trimethylindium (TMI) and the misorientations of the substrates towards (011) and (01~). The average apparent activation energy for indium incorporation is found to be 9.7 kcal mol-J, which is explained by the presence of indium adducts in the gas phase at low temperatures which decompose at higher growth temperatures. The differences in indium concentrations as a function of the direction and the degree of the misorientation are explained by considering the incorporation processes at the group III sublattice sites at the steps, thereby taking into account the arsenic coverage of the surface. The behaviour of the indium incorporation as a function of the misorientation is described by diffusion of growth species towards the steps, according to the BCF theory, which is counteracted by preferential arsenic desorption from the step edges.

Recent progress in metal-organic chemical vapor deposition of $\left( 000\bar{1} \right)$ N-polar group-III nitrides

“…A similar decrease in the In mole fraction in InGaN layers with increasing misorientation angle was reported for Ga-polar InGaN [128]. Substrate misorientation effects on the incorporation of In into InGaAs layers were reported previously [129]. In addition, differences in the incorporation efficiency of at the multi-atomic steps and on the terraces may play a role in the net indium incorporation in the growing layer.…”

Influence of the substrate misorientation on the properties of N-polar InGaN/GaN and AlGaN/GaN heterostructures

“…20 Substrate misorientation effects on the incorporation of In into InGaAs layers were reported previously. 21 We speculate that the lower step velocity of the growing film at higher misorientation angles/ step densities 22 in conjunction with the low thermal stability of InGaN caused an enhanced indium desorption at lower step velocities. In addition, differences in the incorporation efficiency of indium at the multiatomic steps and on the terraces may play a role in the net indium incorporation in the growing layer.…”

Misfit dislocation formation in lattice-mismatched III - V heterostructures grown by metal - organic vapour phase epitaxy

“…In this system the lattice mismatch f between the epitaxial layers and the substrate was between −1.5 × 10 −4 and −8.3 × 10 −4 . During the growth of the In x Ga 1−x As epilayers on GaAs, with indium concentrations between 0.5 and 2.5%, trimethylindium (TMI) was added to the gas phase [20]. Here the lattice mismatch varied between 3.8 × 10 −4 and 13 × 10 −4 .…”