Low-k etching using CF3I, a path to overcome current BEOL integration issues

CF₃I, a low greenhouse warming potential gas, has been used for low-k etching using an ICP reactor. Key parameters such as reactor pressure, bias power, ICP power and total gas flow rate were investigated to develop an optimized etch process. A comparison with standard fluorocarbons such as CF₄, C₄F₈ or CF₃H has been made to illustrate the performances of this low environmental impact chemistry.