THIN FILM FORMATION METHOD, AND MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To provide a thin film formation method excelling in a residual film controlling property capable of setting a residual film after etching at a certain film thickness. SOLUTION: This method of forming a thin film including a first portion having a first film thickness and a second portion having a second film thickness smaller than the first film thickness. The method includes processes of; forming the thin film having the first film thickness on a substrate; acquiring an interference waveform upon film formation being an interference waveform of reflected waves by irradiating the thin film in film formation with laser light; etching the second portion of the thin film; acquiring an interference waveform upon etching by irradiating, with laser light, the second portion; and calculating an interference waveform upon target etching being an interference waveform in a state where the second portion is set at the second film thickness, based on the interference waveform upon film formation. The method is characterized in that the etching is stopped when the interference waveform upon etching becomes the same as the interference waveform upon target etching. COPYRIGHT: (C)2010,JPO&INPIT