KR-20260064345-A - An ellipse measuring instrument using a reflector

KR20260064345AKR 20260064345 AKR20260064345 AKR 20260064345AKR-20260064345-A

Abstract

The present invention provides an ellipsometer using a reflector, characterized by comprising: a stage portion on which a sample is placed; a light source portion that irradiates incident light toward the sample; a polarization state control portion disposed between the light source portion and the sample to polarize the incident light; a reflector portion that reflects the incident light reflected from the sample after the incident light polarized by the polarization state control portion is irradiated onto the sample; a light splitting portion disposed between the light source portion and the polarization state control portion to allow the incident light irradiated from the light source portion to pass through, and to reflect the measurement light reflected from the sample after being reflected to the sample by the reflector portion; and a light detector portion disposed adjacent to the light splitting portion to detect the optical characteristics of the measurement light reflected by the light splitting portion.

Inventors

조용재
제갈원

Assignees

한국표준과학연구원

Dates

Publication Date: 20260507
Application Date: 20241031

Claims (12)

A stage section where the sample is placed; A light source unit that irradiates incident light toward the above sample; A polarization state control unit disposed between the light source unit and the sample to polarize the incident light; A reflection unit that reflects incident light back to the sample after incident light polarized by the polarization state control unit is irradiated onto the sample; A light splitting unit disposed between the light source unit and the polarization state control unit, which passes incident light irradiated from the light source unit and reflects measurement light reflected from the sample after being reflected to the sample by the reflecting unit; and An ellipsometer using a reflection unit characterized by including a light detection unit positioned adjacent to the light splitting unit and detecting the optical characteristics of the measurement light reflected by the light splitting unit.
In Article 1, An ellipsometer using a reflector, further comprising: a focusing optical unit disposed between the polarization state control unit and the sample, which focuses incident light polarized by the polarization state control unit onto the sample and focuses measurement light reflected from the sample onto the polarization state control unit.
In Article 2, The above polarization state control unit is, A fixed linear polarizer positioned adjacent to the above-mentioned light splitter to linearly polarize incident light passing through the above-mentioned light splitter; and An ellipsometer using a reflector, characterized by including: a constant velocity rotating polarizer disposed between the fixed linear polarizer and the focusing optical unit, which rotates incident light linearly polarized by the fixed linear polarizer and rotates measurement light collected by the focusing optical unit.
In Article 2, An ellipsometer using a reflector, characterized in that the above-mentioned focusing optical part is a focusing variable lens that changes the position of incident light focused on the sample by varying the focal distance between the sample and the above-mentioned focusing optical part.
In Paragraph 4, An ellipsometer using a reflector, characterized in that the reflector moves parallel to the incident light irradiated from the light source and the measurement light reflected from the sample according to the position of the incident light changed by the focus-variable lens, thereby reflecting the incident light whose position changes to the sample.
In Paragraph 4, An ellipsometer using a reflective section characterized in that the above-mentioned beam splitter is a polka dot beam splitter composed of reflective micro-circular mirrors on the surface of a material capable of transmitting broadband wavelengths from vacuum ultraviolet to near-infrared regions.
In Paragraph 4, The above-mentioned reflective part is, A lens member formed to have a predetermined curvature and reflecting incident light whose position changes to the sample; and An ellipsometer using a reflector, characterized by including: an extension member extending from both ends of the lens member to be parallel to the incident light irradiated from the light source and the measurement light reflected from the sample.
In Article 1, An ellipsometer using a reflector characterized in that the reflector is formed to have a flat plate shape and is positioned to look at the sample at an angle.
In Article 1, The light source unit, the polarization state control unit, and the light splitting unit are arranged on the same axis, and An ellipsometer using a reflector, characterized in that the light detection unit is spaced apart from the light splitting unit so as to be perpendicular to the incident light.
In Article 2 or Article 3, The above-mentioned reflective portion is formed to have a predetermined curvature, and An ellipsometer using a reflector, characterized in that one concave surface of the reflector is positioned to look at the sample at an angle.
In Article 2 or Article 4, The light source unit, the polarization state control unit, the focusing optical unit, and the light splitting unit are arranged on the same axis, and An ellipsometer using a reflector, characterized in that the light detection unit is spaced apart from the light splitting unit so as to be perpendicular to the incident light.
In Paragraph 3, The light source unit, the fixed linear polarizer, the constant velocity rotating polarizer, the focusing optical unit, and the light splitting unit are arranged on the same axis, and An ellipsometer using a reflector, characterized in that the light detection unit is spaced apart from the light splitting unit so as to be perpendicular to the incident light.

Description

An ellipse measuring instrument using a reflector The present invention relates to an ellipsometer using a reflective part, and more specifically, to an ellipsometer using a reflective part that achieves miniaturization by arranging a reflective part on the upper side of one side of a sample and sequentially arranging a light source part, a light splitting part, and a polarization state control part on the upper side of the other side of the sample along the same axis. The importance of technology capable of non-contactly measuring and evaluating the thickness of thin films and the shape and properties of nano-patterns without damaging nano-specimens is increasingly growing in manufacturing processes for rapidly developing industries such as semiconductor devices, flat-panel displays, nanobiotechnology, nanoimprinting, and thin-film optics. As these industries continue to develop, the thickness of thin films has become increasingly smaller, reaching the level of a few atomic layers, and the shape of nano-patterns is trending toward becoming more complex, shifting from conventional two-dimensional structures to three-dimensional structures. Among non-contact technologies for measuring the shape and physical properties of specimens, ellipsometers and methods utilizing them are widely used alongside advancements in light sources, photodetectors, and computers. A non-contact ellipsometer according to the above requirements generally comprises a light source that irradiates incident light onto a sample, an incident-side polarizing unit that polarizes the incident light, an incident-side collecting unit that collects the polarized incident light onto the sample, a reflective-side collecting unit that collects the measurement light reflected from the sample, a reflective-side polarizing unit that polarizes the collected measurement light, and a detector unit that detects the optical characteristics of the polarized measurement light. However, the aforementioned conventional technology had a problem of being restricted by location due to the increased volume of the equipment resulting from having an inclined incidence structure. (Patent Document 1) Korean Registered Patent Publication No. 10-1698022 (January 13, 2017) FIG. 1 is a conceptual diagram showing an ellipsometer using a reflector according to a first embodiment of the present invention. FIG. 2 is a conceptual diagram showing an ellipsometer using a reflector according to a second embodiment of the present invention. FIG. 3 is a conceptual diagram showing an ellipsometer using a reflector according to a third embodiment of the present invention. Figures 4 (a) and 4 (b) are conceptual diagrams showing an ellipsometer using a reflector according to the fourth embodiment of the present invention. Figures 5(a) and 5(b) are detailed partial views showing the movement of the focusing optical system as the focal length varies in an ellipsometer using a reflector according to the fourth embodiment of the present invention. The present invention will be described below with reference to the attached drawings. However, the present invention may be implemented in various different forms and is therefore not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals. Throughout the specification, when it is stated that a part is "connected (connected, in contact, combined)" with another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other members interposed between them. Furthermore, when it is stated that a part "includes" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components. The terms used herein are merely for describing specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Embodiments of the present invention will be described in detail below with reference to the attached drawings. 1. First embodiment Hereinafter, an ellipsometer using a reflector according to the first embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a conceptual diagram showing an ellipsometer using a reflector according to a first embodiment of the present invent