The band gap of InAsSbP and InGaAsSb alloys enriched with InAs correspods to the spectral range 2.5 - 5 μm which make possible to manufacture LEDs and detectors for the second atmosphere window. Elevated hardness (see Fig.1a ) and small plasticity of the alloys results in an inversed plastic deformation process during LPE growth of InAsSbP (InGaAsSb) on InAs substrate.That is when growing graded( grad a ≈5*10−8 epilayers at elevated temperatures ( 680 - 720° C ) misfit dislocations are formed throughout the entire substrate thickness (C). Simultaneously with increasing dislocation density in InAs ( curves 1,3 ), the curvature of the structure increased within æ = 0.02-0.2 cm−1.