Abstract: The morphology and density distribution of etch pits formed by Schaake and Chen etchants on the {111} B face of HgCdTe liquid phase epitaxy films are studied.The experimental results of the deep etches show that threading dislocations with certain orientations really exist in the epilayer.After both etchants acted on the same sample,it is observed that most of the etch pits formed by Schaake and Chen etchants have a one-to-one correspondence in distribution.In addition to these etch pits,it is also found that there is another kind of etch pit for both Schaake and Chen etchants,but neither of them threads the HgCdTe epilayer.Their density distributions and density multiplications near the interface are the same.These etch pits formed by the Schaake etchant also have a multiplication around macroscopic defects,but this phenomena is not observed for those of the Chen etchant.

Key words: defect, dislocation, etch pit, Schaake, Chen, HgCdTe