MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE AND MANUFACTURING DEVICE OF SEMICONDUCTOR

PROBLEM TO BE SOLVED: To control the endpoint of etching accurately.SOLUTION: An etching device 1 has a processing unit 2 and a control unit 3. Emission intensity of plasma in the processing unit is acquired by an OES detector 21, and an etching controller 31 determines a regression equation by nonlinear regression analysis. The nonlinear regression analysis is performed using the emission intensity of plasma acquired before a first time when the emission intensity of plasma exceeded a peak, and a second time becoming the etching endpoint is calculated using the regression equation. The etching endpoint is calculated as a time when the emission intensity decreases by a predetermined value from the first time. When the etching endpoint is reached, the etching device 1 terminates the etching.