Optical diagnostics of semiconductor process using hyperspectral imaging

A method for measuring at least one property of at least one layer or structure formed on a substrate disposed in a semiconductor processing system, comprising:

• initiating a process step in the semiconductor processing system;
• illuminating the substrate with an illumination beam, the portion of the illumination beam reflected and diffracted from the substrate forming a diffracted optical signal;
• collecting the diffracted optical signal through a window mounted in a wall of the semiconductor processing system, and through collecting optics;
• tunably selecting a wavelength of either the illumination beam or the diffracted optical signal using a wavelength tunable filter disposed in either the illumination beam or the diffracted optical signal, respectively, to form a wavelength-filtered diffracted optical signal;
• detecting the wavelength-filtered diffracted optical signal using an array detector;
• and
• storing and processing images acquired by the array detector in a controller,
• wherein the controller is configured for controlling at least the wavelength tunable filter and the array detector.

A method for inspecting a substrate in a substrate inspection system, comprising:

• placing the substrate on a stage in the substrate inspection system;
• illuminating the substrate with an illumination light source;
• collecting an optical signal caused by illuminating the substrate, through collecting optics;
• directing the collected optical signal from the collecting optics into a wavelength tunable filter for tunably selecting a wavelength of the collected optical signal;
• detecting the wavelength-filtered signal using an array detector;
• and
• storing and processing images acquired by the array detector in a controller,
• wherein the controller is configured for controlling at least the wavelength tunable filter and the array detector.