The process of obtaining a modified structure for quantum cascade lasers is studied; this process includes growth using molecular-beam epitaxy, plasma etching, photolithography with the use of liquid etching, and the formation of special contacts for decreasing losses in the waveguide. The use of a special type of structure makes it possible, even without postgrowth overgrowth with a high-resistivity material, to attain parameters satisfying requirements to heterostructures in high-quality quantum cascade lasers at maximal simplification of the entire preparation process.

The characteristics of lasers of the 1.44–1.46-μm optical range grown on GaAs substrates using a metamorphic buffer are studied. The active region of the laser contains 10 rows of InAs/In_0.4Ga_0.6As/In_0.2Ga_0.8As quantum dots. It is shown that the use of special selective high-temperature annealing along with the application of short-period In_0.2Ga_0.8As/In_0.2Al_0.3Ga_0.5As short-period superlattices makes it possible to substantially decrease the density of threading dislocations in the active region. A threshold current density of 1300 A cm^–2, external differential quantum efficiency of 38%, and maximal pulsed-mode output power of 13 W are attained for a laser with a broad area 3 mm in length.