Substrate measurement system, method of measuring substrate, and computer program product

A substrate measurement system comprising:

• a positional alignment apparatus configured to measure a positional relationship between a first mark of a first layer and a second mark of a second layer by radiating signal light onto a substrate;
• a film thickness measuring apparatus configured to measure a film thickness;
• a control device configured to control positional relationship measurement in the positional alignment apparatus, and film thickness measurement in the film thickness measuring apparatus, and
• a signal intensity measuring apparatus configured to radiate the signal light onto a test substrate and measure intensity of the signal light reflected,
• wherein the control device executes
• sending a first instruction measuring a film thickness of a first processing object disposed above a plurality of test substrates with a third mark, to the film thickness measuring apparatus;
• sending a second instruction measuring intensity of signal light reflected when the signal light is radiated onto the third mark via the first processing object above the test substrates, by use of a plurality of different wavelengths of the signal light respectively for the test substrates, to the signal intensity measuring apparatus;
• creating the wavelength selection reference information, based on a correlation between values of the film thickness of the first processing object, wavelengths of the signal light, and degrees of intensity of the signal light;
• sending a third instruction measuring a film thickness of a second processing object disposed above the substrate with a fourth mark, to the film thickness measuring apparatus;
• selecting a wavelength that provides a highest degree of intensity of signal light reflected when the signal light is incident onto the fourth mark via the second processing object having the value of the film thickness measured by the film thickness measuring apparatus, based on wavelength selection reference information;
• and
• sending a fourth instruction measuring the fourth mark on the substrate by use of signal light having the wavelength that is selected according to the film thickness of the second processing object, to the positional alignment apparatus, and
• the film thickness of the second processing object is a film thickness at a predetermined position on the substrate.

A method of measuring a substrate, the method comprising:

• measuring a film thickness of a first processing object disposed above a plurality of test substrates with a first mark;
• measuring intensity of signal light reflected when the signal light is radiated onto the first mark via the first processing object above the test substrates, with respect to a plurality of wavelengths;
• creating wavelength selection reference information, based on a correlation between values of the film thickness of the first processing object, wavelengths of the signal light, and degrees of intensity of the signal light;
• measuring a film thickness of a second processing object disposed above a substrate with a second mark;
• selecting a wavelength that provides a highest degree of intensity of signal light reflected when the signal light is incident onto the second mark via the second processing object having the value of the film thickness, based on the wavelength selection reference information;
• and
• measuring the second mark on the substrate by use of light having the wavelength that is selected according to the film thickness of the second processing object in a positional alignment apparatus,
• wherein the film thickness of the second processing object is a film thickness at a predetermined position on the substrate.