Comparative analysis of the optical and physical properties of inas and InAs, In$_{0.8}$Ga$_{0.2}$As quantum dots and solar cells based on them

InAs and InAs, In$_{0.8}$Ga$_{0.2}$As quantum dots in a GaAs matrix as well as GaAs solar cells with quantum dots of both types in the $i$-region are obtained by metalorganic vapor-phase epitaxy. As a result of investigations by photoluminescence and transmission electron microscopy, it is found that the InAs, In$_{0.8}$Ga$_{0.2}$As quantum-dot array is highly uniform, contains a smaller number of large imperfect quantum dots, and also provides a decrease in mechanical stresses in the structure. An analysis of the spectral dependences of the internal quantum yield shows that the quality of a solar-cell matrix after embedding up to 20 rows of InAs, In$_{0.8}$Ga$_{0.2}$As quantum dots remains at a level close to the reference GaAs solar cells. In this case, a linear increase in the additional photocurrent generated due to the absorption of sub-bandgap photons in InAs, In$_{0.8}$Ga$_{0.2}$As quantum dots is provided with an increase in the number of rows of quantum dots, since the value of the photocurrent gain per row is preserved.