This paper addresses problems associated with thermal annealing andn‐type andp‐type doping in CuInS2. The results of incorporating impurities like Zn and P in CuInS2single crystals by different methods are reported. Some evidence has been provided to explain the formation of precipitates being the limiting factor to exhibit the shallow acceptor property. The electron beam annealing of phosphorus‐implanted CuInS2has been shown for the first time to be an effective way forp‐type conductivity control by extrinsic impurities in any I‐III‐VI2ternary chalcopyrite.