Photoluminescence intensity measurements from GaAs/AlGaAs and InGaAs/InAlAs quantum well probe structures have been used to study dry-etch damage inflicted in low power reactive ipn etching environments. Selective etching has been employed to accumulate damage in the materials under these relatively low damage conditions. The measured data are consistent with calculations for channeling effects of atomic ion species, using a microscopic ion channeling theory. The results indicate that atomic as opposed to molecular ion channeling may be the main mechanism for deep dry-etch damage in these environments, which suggests that gases can be selected as likely to cause low damage.