Measuring apparatus and film formation method

A measuring apparatus for measuring a film thickness of a film formed on a surface of a substrate or a depth of a processed surface processed on a substrate surface by optical interference means, comprising:

• irradiation means capable of irradiating measuring light from the back of the substrate such that said measuring light is totally reflected from an interface between a film formed on the substrate surface and the substrate and from a processed surface of the substrate or a film surface;
• and
• measurement means for measuring a film thickness or a processing depth by causing said reflected light from said interface and said reflected light from the processing surface or the film surface to interfere with each other;
• wherein:
• said irradiation means can irradiate irradiation light to the back of said substrate at different angles of incidence, and can vary the angle of incidence of said irradiation light so that an optical path difference of said irradiation light passing through said substrate is greater than a wavelength of incident light, and an optical path difference due to the film thickness of the film or the processing depth as an object of measurement is smaller than the wavelength of said incident light.

A thin film formation apparatus for forming a thin film on a substrate, comprising:

• irradiation means for irradiating, from a back of a substrate, measuring light such that said measuring light is totally reflected by an interface between a film formed on a substrate surface and the substrate;
• measurement means for measuring a film thickness by causing reflected light from the interface and reflected light from a surface of the film to interfere with each other;
• and
• means for forming a thin film on the substrate by feeding back the film thickness measured by said measurement means.

A processing apparatus of a substrate surface, comprising:

• means for irradiating measuring light from a back of a substrate such that said measuring light is totally reflected from both substrate surface and processed surface of the substrate;
• means for measuring a processing depth by causing reflected light from the substrate surface and reflected light from the processing surface to interfere with each other;
• and
• means for processing the substrate surface on the basis of the processing depth measured by said means for measuring the processing depth.

A method of forming a thin film, comprising the steps of:

• irradiating measuring light from a back of a substrate such that said measuring light is totally reflected from an interface between a film formed on a substrate surface and the substrate;
• causing reflected light from the interface and reflected light from the surface of the film to interfere with each other, and thereby measuring the film thickness;
• calculating a difference between the film thickness so measured and a target value of a film thickness set in advance;
• and
• controlling a processing condition of film formation on the basis of the difference.

A method of processing a substrate surface, comprising the steps of:

• irradiating from a back of a substrate measuring light such that said reflecting light is totally reflected from a substrate surface and from a processed surface formed on the same side as the substrate surface;
• causing reflected light from the substrate surface and reflected light from the processed surface to interfere with each other, and thereby measuring a processing depth;
• calculating a difference between a processing depth so measured and a target value of a processing depth set in advance;
• and
• controlling a processing condition of the substrate surface on the basis of the difference.