The results of a Cl2/ N2 inductively coupled plasma (ICP) reactive ion etching process on InAs/GaSb superlattices infrared focal plane arrays were reported. A standard PIN device structure based on GaSb substrate was applied in all samples grown by molecular beam epitaxy. The etching results including etching rate and mesa sidewall profile were affected by gas flow ratios directly, The higher the chlorine content was, the higher the etching rate was. When the nitrogen content increases, the etching rate decreases and tends to a certain value. When other parameters such as chamber pressure et al. were fixed, the etching rate and selection ratio increased linearly with temperature increasing. The mesa tended to be right angle, and the layered texture profile gradually disappeared, while the channel became rough and even pitted. Within the scope of this study, ICP and RF power had little effect on the etching results.