A thin film measuring device and method

Abstract

The invention discloses a thin film measurement apparatus and a thin film measurement method. The thin film measurement apparatus comprises: an illumination unit for providing an illumination light beam; a first imaging lens group, wherein the first imaging lens group comprises an objective lens, and is used for irradiating the illumination light beam onto a thin film positioned at a transparent substrate through the objective lens, and collecting the reflection light beams of the thin film and the transparent substrate; a visual field diaphragm, wherein the visual field diaphragm and the thinfilm form conjugate about the objective lens, and the visual field diaphragm is used for limiting the crosstalk of the reflection light of the transparent substrate lower surface on the measure lightso as to obtain more effective signals; an area array for detecting the distribution of the light beam passing through the visual field diaphragm; and a processor for collecting the imaging angle spectrum information of the illumination light beam with the incident angle of greater than a critical incident angle and calculating the parameters of the thin film according to the angle spectrum information. According to the present invention, through the low reflectivity of the transparent substrate, the visual field diaphragm is arranged in the angle spectrum imaging optical path, such that thereflection light of the transparent substrate lower surface is removed so as to improve the signal-to-noise ratio of the upper layer reflection signal.

Description

technical field [0001] The invention relates to the field of integrated circuit manufacturing, in particular to a thin film measuring device and method. Background technique [0002] Characteristic parameter detection is widely used in the industrial field, and the manufacturing process requires monitoring the quality of characteristic parameters to ensure product quality and improve yield. The measurement of characteristic parameters is divided into two categories: non-destructive measurement and destructive measurement. Since the destructive measurement will have a destructive effect on the surface of the characteristic parameter, the nondestructive measurement using the optical method is the most commonly used method in the detection of the characteristic parameter. [0003] Existing equipment is very mature for the detection of characteristic parameters of opaque substrates. The commonly used detection methods include reflectometer measurement and ellipsometer measureme...

AI Technical Summary

Problems solved by technology

However, when the substrate of the object to be measured is transparent, since the influence of reflected light from the transparent substrate cannot be removed, it will interfere with the measurement

Therefore, none of the above methods can completely eradicate the interference caused by the light reflected by the transparent substrate, resulting in inaccurate measurement results

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