In this study, He/O2 plasma mixture, induced in a radio frequency (RF) low‐pressure remote plasma system, has been characterized and employed for polymer surface modification. Actinometry optical emission spectroscopy (AOES) and Langmuir probe techniques were used to evaluate the plasma active species contributing to polymer surface modification. These active species involve the atomic oxygen [O] and the electrons (ne). Five different polymers (poly(methyl methacrylate) [PMMA], polytetrafluoroethylene [PTFE], polyethylene [PE], polyvinyl chloride [PVC], and polystyrene [PS]) were plasma treated and subsequently characterized for etching rate, surface morphology using atomic force microscopy (AFM) technique, and chemical elemental composition using X‐ray photoelectron spectroscopy (XPS) technique.