Ternary PbSnSe layers with various Sn contents were grown by LPE on Si(1 0 0) substrates prepared with MBE-grown PbSe/BaF2/CaF2 buffer layers. LPE growth initiation temperatures were varied from 380 to 475 degrees C by changing the chalcogen concentration in the LPE growth solution. PbSe/PbSnSe double layers were also grown using the same procedure. Crack densities and residual strain values in the epilayers were measured by optical Nomarski microscopy and high-resolution X-ray diffraction (HRXRD). Crack densities in Pb0.91Sn0.09Se layers decreased from 93 to 33 cracks/cm when the growth temperature was increased from 430 to 475 degrees C. Crystalline quality, as indicated by HRXRD FWHM reduction from 522 to 442 arcsec, also improved with this increase in growth initiation temperature. These results show that IV-VT semiconductor layers grown at higher temperatures are more able to plastically deform when subjected to cooling strain caused by thermal expansion mismatch with the Si substrate. Activation of a strain-relieving higher-order dislocation glide mechanism is a likely explanation for this observation.