Dry etching of HgCdTe using Inductively Coupled Plasma(ICP) was studied to reduce crosstalk in 2D array IR detector. The damage of dry etching and the method of removing the damage were also studied for further application. ICP has merits of producing high ion density as well as independently controlling ion bombardment energy and amount of polymer since ICP differs from RIE or ECR in the point that the former has two power supplies composed of a plasma RF power and a substrate RF power while the latter has only one power supply. The effects of various process parameters on anisotropic etching and etch rate and surface morphology were investigated. From the results of the experiments, we could obtain good surface morphology and high etch rate up to 2700 Å/min and excellent anisotropic etching. However, the damage that converts p type into n type was observed after dry etching. The depth and lateral distance of type conversion for 22minutes etching were about 30 μm by differential Hall measurement and the type conversion disappeared completely after thermal annealing at 200℃ for 15 hours after dry etching which shows that the hydrogen involved in etch gas is the major cause of type conversion. It is supposed that the ICP is effective for dry etching of HgCdTe and low damage and the origin of type conversion is hydrogen.
