| 摘要 |
Provided is an endpoint detecting method capable of accurately detecting an endpoint of a shape formation process even when a shape formed on the surface of a substrate is changed. The light with a wavelength when the timing of the formation completion of a certain shape formed in a treated area A corresponds to the appearance timing of a certain point in which the time of intensity is unusually changed is set as monitor light. When etching treatment is performed on a substrate S using plasma, a radiating unit (14) radiates the treated area A of the surface of the substrate S with radiating light L having a certain wavelength range containing multiple wavelengths. The time change in the intensity of the monitor light set among reflected light R received by a light receiving unit (15) is monitored. It is determined whether the time change in the intensity of the monitor light approaches a certain point in which the intensity in an intensity change profile is unusually changed. If it is determined that the time change in the intensity of the monitor light approaches the certain point, it is determined that the formation of a certain shape formed in the treated area A is completed. [Reference numerals] (AA) Detecting an end point; (BB) No; (CC) Yes; (DD) End; (S41) Determining monitor light; (S42) Monitoring the intensity of the monitor light; (S43) Is it reached to a certain point?; (S44) Completing the formation of a certain shape |
