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Beam‐profile reflectometry is a new technique for measuring the thickness and optical constants of dielectric, semiconducting, and thin metal films. The technique consists of measuring the intensity profile of a highly focused beam reflected from the sample. By using a linearly polarized light source and a tightly focussed beam, the S‐ and P‐polarization reflectivities of the film are simultaneously obtained over a wide range of angles. The focusing also provides a submicrometer spot, thus allowing these measurements to be performed in very small geometries. How the information present in the reflectivity profiles can reveal information about as many as three unknown film parameters simultaneously is described, and results from film samples for which the multiparameter fitting capability was essential to the success of the measurement are also presented.

A new technique is described for measuring the distance between a lens and reflecting surface extremely accurately. It is based on the sharply peaked depth response of type II confocal systems. By dithering either the sample or the optical system, a differential measurement is generated, placing a zero-crossing at the peak of the depth response and improving the ranging accuracy. The technique is independent of surface roughness or tilt and hence is useful for robotics or machining applications. Sensitivities to surface vibrations of 0.01 nm and thin film measurements to 0.04 microm demonstrated. Signal-to-noise calculations are presented, and the procedure for measuring the thickness of transparent films is outlined.

We describe a new technique for measuring the thickness and optical constants of dielectric, semiconducting, and thin metal films. Beam profile reflectometry provides excellent precision for films as thin as 30 A and as thick as 20 000 A. The technique is also capable of simultaneous 2 and 3 parameter measurements and it performs all measurements with a submicron spot size.

We have developed a novel technique for performing simple phase-sensitive optical measurements in a sub-micrometer area. We presently use this technique to measure film stacks commonly found in the semiconductor industry. This article explains the theory behind this technique and presents several examples demonstrating the capabilities of the system.

Measurements of ultra-thin films (