METHOD FOR ETCHING OF TANTALUM NITRIDE

A method of etching a tantalum nitride layer is provided to ensure a sufficient etching rate by using a BCl3 gas as a main etching gas, while removing a natural oxide layer generated on a surface. A gate dielectric layer(22) made of a material having a high dielectric constant is deposited on a semiconductor substrate(21), and then a tantalum nitride layer(23) serving as an electrode is formed on the gate dielectric layer. The tantalum nitride layer is etched, while a natural oxide layer(24) formed on a surface of the tantalum nitride layer is removed by using a gas containing boron as a main etching gas. The step of etching the tantalum nitride layer uses a BCl3 gas as a main etching gas, which is mixed with an argon gas and an oxygen gas.