Abstract: An optical measurement system for evaluating the surface of a substrate or the thickness and optical characteristics of a thin film layer overlying the substrate includes a light source for generating a light beam, a static polarizing element for polarizing the light beam emanating from the light source, and a measurement system for measuring the light reflected from the substrate location. The measurement system includes a static beam splitting element for splitting the light reflected from the substrate into s-polarized light and p-polarized light. The measurement system further includes two optical sensors for separately measuring the amplitude of the s-polarized light and the intensity of the p-polarized light. A control system analyzes the measured amplitude of the s-polarized light and the p-polarized to determine changes in the topography of substrate or changes in the thickness or optical characteristics of the thin film layer.

Abstract: An optical measurement system for evaluating the surface of a substrate or the thickness and optical characteristics of a thin film layer overlying the substrate includes a light source for generating a light beam, a static polarizing element for polarizing the light beam emanating from the light source, and a measurement system for measuring the light reflected from the substrate location. The measurement system includes a static beam splitting element for splitting the light reflected from the substrate into s-polarized light and p-polarized light. The measurement system further includes two optical sensors for separately measuring the amplitude of the s-polarized light and the intensity of the p-polarized light. A control system analyzes the measured amplitude of the s-polarized light and the p-polarized to determine changes in the topography of substrate or changes in the thickness or optical characteristics of the thin film layer.

Abstract: An optical measurement system for evaluating the surface of a substrate or the thickness and optical characteristics of a thin film layer overlying the substrate includes an intensity stabilized light source configured to generate a stabilized light beam, a polarizing element for polarizing the light beam emanating from the light source, and a detection system for measuring the light reflected from the substrate The measurement system includes a polarizing beam-splitter for splitting the light reflected from the substrate into s-polarized light and p-polarized light. The measurement system further includes two optical sensors for separately measuring the amplitude of the s-polarized light and the intensity of the p-polarized light and a third detector for measuring either the phase difference between the s-polarized light and the p-polarized light or the reflection angle of the light reflected from the substrate.

Abstract: A method and apparatus for inspecting a reflective surface, or material on such surface, such as lubricant and planarizing layers on a substrate surface. A beam of controlled polarization impinges obliquely at a spot in the plane of the substrate. A collector such as an integrating sphere is spaced away from the substrate and has an opening oriented to catch the oblique specular reflectance from the surface. Preferably the opening is substantially larger than the beam, so that substrate run out does not send the beam astray or defeat its measurement, and the oblique beam is aimed at an angle lying between the Brewster angle of the lubricant and that of the adjacent layer. A temperature-controlled laser diode with constant-current driver provides a beam that is free of wavelength hops and amplitude changes, making beam aiming repeatable and allowing point-by-point comparisons of the detected reflectance.