A polarizing assembly and broadband ellipsometry apparatus

Abstract

The utility model discloses a polarization subassembly and wide wave band ellipsometer, polarization subassembly includes: fixed part, a plurality of be used for the polarization piece of different wave band light beam and be used for driving fixed part rotation's drive mechanism, fixed part includes a plurality of subarea and opening, a plurality of be used for the polarization piece of different wave band light beam is fixed in a plurality of subarea respectively, opening and drive mechanism fixed connection, a plurality of subarea equidistance encircle opening. Ellipsometer adopts the polarization subassembly of the utility model embodiment to start polarization, can realize wide wave band ellipsometer.

Description

Technical Field

[0001] This utility model relates to the field of broadband elliptic measurement technology, and in particular to a polarization component and a broadband elliptic measurement device. Background Technology

[0002] An ellipsometer is a key instrument that determines the thickness and optical constants of thin films by measuring the change in polarization state of light during reflection or transmission on a sample surface. It is widely used in semiconductor manufacturing, optical coating, and biomaterials testing.

[0003] Rotating compensator (RCE) ellipsometers have become the mainstream structure due to their high accuracy and wide spectral adaptability, and one of their core components is the polarizer. The performance of the polarizer (transmittance, extinction ratio, spectral bandwidth) directly determines the accuracy and range of ellipsometric measurements.

[0004] Currently, commonly used polarizer materials include quartz, MgF2, and polymer films. Although these materials have good polarization performance in certain wavelength bands, it is difficult for a single-material polarizer to simultaneously cover a wide wavelength range from deep ultraviolet (190nm) to near infrared (2500nm). Utility Model Content

[0005] This invention provides a polarization component and a wideband ellipticity measurement device, which can perform wideband ellipticity measurements.

[0006] In a first aspect, this utility model provides a polarization component, including: a fixing member, a plurality of polarizers for transmitting beams of light of different wavelengths, and a driving mechanism for driving the fixing member to rotate.

[0007] The fastener includes multiple partitions and openings; the multiple polarizers for transmitting beams of different wavelengths are respectively fixed to the multiple partitions;

[0008] The opening is fixedly connected to the driving mechanism, and the multiple partitions surround the opening at equal intervals.

[0009] Optionally, the plurality of polarizers for transmitting beams of different wavelengths include at least two of the following polarizers: a first polarizer for transmitting deep ultraviolet beams, a second polarizer for transmitting visible beams, and a third polarizer for transmitting near-infrared beams.

[0010] Optionally, the plurality of partitions on the fixing member are annular partitions with threads on their inner surfaces, and the plurality of polarizers for transmitting beams of different wavelengths are installed on the plurality of partitions by threaded connections.

[0011] Optionally, the drive mechanism is a hollow direct drive motor; the opening is directly connected to the shaft of the hollow direct drive motor.

[0012] Optionally, the first polarizer is a MgF2 polarizer, the second polarizer is a quartz polarizer, and the third polarizer is a liquid crystal polymer polarizer.

[0013] Secondly, this utility model embodiment also provides a wideband ellipsometric measurement device, including: a light source, a polarization component as described in the above embodiment, a second rotating motor, a polarization analyzer, and a spectrometer;

[0014] The second rotating motor is hollow, and a compensation waveplate is installed at the hollow position of the second rotating motor;

[0015] The light beam emitted by the light source is converted into linearly polarized light by the polarization component, passes through the compensation waveplate and reaches the surface of the sample. The light reflected by the sample passes through the analyzer and enters the spectrometer.

[0016] Optionally, the light source may include multiple sub-light sources in different wavelength bands.

[0017] Optionally, the plurality of sub-light sources of different bands include at least two of the following sub-light sources: a first light source for emitting a visible band light beam, a second light source for emitting a deep ultraviolet band light beam, and a third light source for emitting a near-infrared band light beam.

[0018] Optionally, it may also include multiple light-blocking plates, each of which is used to block the light beam emitted by each of the sub-light sources.

[0019] Optionally, multiple beam combiners applicable to all bands may also be included;

[0020] The multiple beam combiners applicable to all wavelengths are configured to send the light beams emitted by the multiple sub-light sources of different wavelengths into the optical path of the polarization component.

[0021] This invention provides a polarization component that integrates multiple polarizers for transmitting beams of different wavelengths through multiple partitions, achieving wide-band coverage in a single system. It features a compact structure, high integration, and motor-driven rotation replaces manual individual polarizer replacement, improving component efficiency and online measurement capabilities. The wide-band ellipsometric measurement device provided by this invention, due to the use of the aforementioned polarization component and further optimized integration of multi-band light sources, allows the same instrument to quickly adapt to measurement requirements of different films and processes, resulting in high system integration and strong measurement adaptability.

[0022] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of an existing elliptic measurement system;

[0025] Figure 2 yes Figure 1 A schematic diagram of a rotary motor equipped with a compensating waveplate for an ellipsometry measurement system is provided.

[0026] Figure 3 yes Figure 2 A schematic diagram of a hollow rotating motor without a compensation plate installed;

[0027] Figure 4 This is a partial structural schematic diagram of a polarization component provided in an embodiment of the present invention;

[0028] Figure 5 yes Figure 4 A side view of the overall structure of the polarization component in the image;

[0029] Figure 6 This is a schematic diagram of the structure of a broadband ellipsometry measuring device provided in an embodiment of this utility model;

[0030] Figure 7 This is a schematic diagram of another wideband ellipticity measurement device provided in this embodiment of the present invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] Figure 1 This is a schematic diagram of an existing ellipsometry measurement system, for reference. Figure 1 The ellipsometric measurement system includes: a light source 110, a first polarizing crystal 120, a rotary motor 130, a second polarizing crystal 140, and a spectrometer 150; wherein the light beam emitted by the light source 110 ( Figure 1 The light beam (in red) is converted into linearly polarized light by the first polarizing crystal 120 (which acts as a polarizer), and then passes through a compensating waveplate 131 installed in the middle of a hollow rotating motor 130. This compensating waveplate 131, for example, can be a quarter-wave plate. The compensating waveplate 131 is fixed in the middle of the rotating motor 130 and rotates uniformly with the rotating motor 130. The light beam then reaches the surface of the sample 200 and is reflected by the sample 200; the reflected light beam (… Figure 1 The light (in green) then passes through a second polarizing crystal 140 (for analysis) and finally enters the spectrometer 150 for collection. In this optical path system, the first polarizing crystal 120 used for polarization is fixed, and the applicable wavelength range of the polarizing crystal is determined by the material used to make the crystal, which cannot be adapted to a very wide wavelength range.

[0034] To facilitate understanding of the existing rotary motor 130, Figure 2 yes Figure 1 A schematic diagram of a rotary motor equipped with a compensating waveplate is provided for the ellipsometry measurement system. Figure 3 yes Figure 2 A schematic diagram of a hollow rotating electric motor without a compensation plate installed, for reference. Figures 1-3 , Figure 1 A compensating waveplate 131 (blue part) is fixedly installed in the hollow position of the rotating motor 130. Figure 2 yes Figure 1 A side view of a rotary motor 130 with a compensation waveplate 131 fixedly installed at the hollow position. Figure 3 This is a side view of the rotary motor 130 without the compensation waveplate 131.

[0035] To address the shortcomings of existing ellipsometry measurement devices in terms of bandwidth coverage, automated switching, and system integration, this invention provides a polarization component and a wideband ellipsometry measurement device, as detailed below: Figure 4 This is a partial structural schematic diagram of a polarization component provided in an embodiment of this utility model. Figure 5 yes Figure 4 A side view of the overall structure of the polarization component in the image, with reference to... Figure 4 and Figure 5 The polarization component 200 includes: a fixing member 210, a plurality of polarizers for transmitting beams of different wavelengths, and a drive mechanism 240 for driving the fixing member 210 to rotate; the fixing member 210 includes a plurality of partitions and an opening 214; the plurality of polarizers for transmitting beams of different wavelengths are respectively fixed in the plurality of partitions; the opening 214 is fixedly connected to the drive mechanism 240, and the plurality of partitions are equidistantly surrounding the opening 214.

[0036] This embodiment uses three bands as an example for illustration. It should be noted that in actual use, users can choose to integrate polarizers with two, four, or any number of bands according to their actual needs; this application does not impose specific limitations in this regard. Referring to the three-band example, continue to refer to... Figure 4 and Figure 5 Multiple polarizers for transmitting beams of different wavelengths may include a first polarizer 220 for transmitting deep ultraviolet beams, a second polarizer 230 for transmitting visible beams, and a third polarizer 240 for transmitting near-infrared beams. Multiple partitions may be correspondingly configured to include a first partition 211, a second partition 212, and a third partition 213. The first polarizer 220 is fixed to the first partition 211, the second polarizer 230 is fixed to the second partition 212, and the third polarizer 240 is fixed to the third partition 213. An opening 214 is fixedly connected to a drive mechanism 240, and the first partition 211, the second partition 212, and the third partition 213 surround the opening 214 and are equidistant from it.

[0037] Specifically, the polarizers used to transmit beams of different wavelengths can be made of different materials or have different optimized coatings to achieve transmission of specific wavelengths. The polarizers used to transmit beams of different wavelengths are integrated into the fixture 210. The fixture 210 is rotated by the drive mechanism 240 to achieve switching between different zones, thereby enabling wide-band measurement in a single ellipsometry.

[0038] This utility model embodiment integrates multiple polarizers for transmitting beams of different wavelengths through multiple partitions, achieving wide-band coverage in a single system. It features a compact structure, high integration, and motor-driven rotation instead of manual individual polarizer replacement, improving component utilization efficiency and online measurement capabilities.

[0039] Optionally, based on the above embodiments, the plurality of polarizers for transmitting beams of different wavelengths include at least two of the following polarizers: a first polarizer 220 for transmitting deep ultraviolet beams, a second polarizer 230 for transmitting visible beams, and a third polarizer 240 for transmitting near-infrared beams. In this embodiment, polarizers of the above three wavelengths are selected for integration, for example, the first polarizer 220 can be a MgF2 polarizer, the second polarizer 230 a quartz polarizer, and the third polarizer 240 a liquid crystal polymer polarizer. In other embodiments, different numbers and materials of polarizers can be selected according to actual needs.

[0040] It should be noted that because MgF2 material maintains high transmittance in the deep ultraviolet band, it is suitable for deep ultraviolet ellipsometric measurements, such as 190-400 nm. Quartz material is more suitable for visible band ellipsometric measurements, such as 400-900 nm. Liquid crystal polymer polarizers are more suitable for near-infrared band ellipsometric measurements, such as 900-1700 nm.

[0041] Optionally, based on the above embodiments, the multiple partitions on the fastener are annular partitions with threads on the inner surface, and multiple polarizers for transmitting beams of different wavelengths are installed on the multiple partitions by threaded connections.

[0042] Optionally, based on the above embodiments, the drive mechanism is a hollow direct drive motor; the opening 214 is directly connected to the shaft of the hollow direct drive motor.

[0043] Understandably, the shaft of the hollow direct-drive motor with aperture 214 is directly connected, allowing the fixed component 210 to rotate at a fixed angle, thereby rotating the polarizers of different zones into the optical path of the ellipsometric measurement system to achieve ellipsometric measurement. The rotational angular resolution of this hollow direct-drive motor should be better than 0.01°, and the driver can be equipped with an optical encoder with a zero-point reference pulse to ensure the repeatability of zone switching is within ±0.05°.

[0044] Figure 6 This is a schematic diagram of a broadband ellipsometry measuring device provided in an embodiment of this utility model. (Refer to...) Figure 6 The device includes: a light source 110, a polarization component 200 provided in the above embodiment, a second rotary motor 300, an analyzer 140, and a spectrometer 150; the second rotary motor 300 is hollow, and a compensation waveplate is installed at the hollow position of the second rotary motor 300; the light beam emitted by the light source 110 is converted into linearly polarized light by the polarization component 200, passes through the compensation waveplate and reaches the surface of sample A, and the light reflected by sample A passes through the analyzer 140 and enters the spectrometer 150.

[0045] The second rotary motor 300 can be connected with Figure 1 The structure of the rotary motor 130 in the prior art is the same.

[0046] It is understood that by using the polarization component 200 provided in the above embodiments, automatic switching of polarizers can be realized, and wideband ellipsometric measurement can be performed, solving the shortcomings of the prior art in terms of bandwidth coverage, automatic switching and system integration.

[0047] Figure 7 This is a schematic diagram of another wideband ellipticity measurement device provided in this embodiment of the present invention. Optionally, based on the above embodiment, the light source 110 includes multiple sub-light sources of different bands.

[0048] Optionally, based on the above embodiments, the multiple sub-light sources of different bands include at least two of the following sub-light sources: a first light source 111 for emitting visible band light beams, a second light source 112 for emitting deep ultraviolet band light beams, and a third light source 113 for emitting near-infrared band light beams.

[0049] For example, this embodiment uses a sub-light source that simultaneously possesses the above three different wavelengths as an example. It should be noted that in other embodiments, two, four, or other sub-light sources can be selected for integration according to actual needs. (See reference) Figure 7 The light source 110 may include a first light source 111 for emitting a visible light, a second light source 112 for emitting a deep ultraviolet light, and a third light source 113 for emitting a near-infrared light.

[0050] It is understandable that different light sources are required when performing ellipsometric measurements at different wavelengths. The light source 110 of this invention can use a light source that corresponds to the wavelength beam when performing ellipsometric measurements at different wavelengths.

[0051] Optionally, based on the above embodiments, the device further includes multiple light-blocking plates, each of which is used to block the light beam emitted by each sub-light source.

[0052] For example, continue to refer to Figure 7 The wideband ellipsometric measurement device also includes a first light-blocking plate 410 for blocking the light beam emitted by the first light source 111, a second light-blocking plate 420 for blocking the light beam emitted by the second light source 112, a third light-blocking plate 430 for blocking the light beam emitted by the third light source 113, and a motor for controlling the insertion of the first light-blocking plate 410, the second light-blocking plate 420, and the third light-blocking plate 430 into the optical path.

[0053] Understandably, when a light-blocking plate is inserted into the optical path, the light beam is blocked and cannot enter the measurement optical path; when the light-blocking plate is removed, the light beam can enter the measurement optical path. When the system selects the first partition 211, it controls the insertion of the first light-blocking plate 410 and the third light-blocking plate 430, blocking the light beams emitted by the first light source 111 and the third light source 113, allowing only the light beam emitted by the second light source 112 to enter the measurement optical path, thus enabling measurements in the 190-400nm deep ultraviolet band. When the system selects the second partition 212, it controls the insertion of the second light-blocking plate 420 and the third light-blocking plate 430, blocking the light beams emitted by the second light source 112 and the third light source 113, allowing only the light beam emitted by the first light source 111 to enter the measurement optical path, thus enabling measurements in the 400-900nm visible band. When the system selects the third partition 213, it controls the insertion of the first light-blocking plate 410 and the second light-blocking plate 420 to block the light beams emitted by the first light source 111 and the second light source 112, allowing only the light beam emitted by the third light source 113 to enter the measurement optical path, thus enabling measurement in the 900-1700nm infrared band.

[0054] The light source of this utility model embodiment adopts a first light source 111 for emitting visible light, a second light source 112 for emitting deep ultraviolet light, and a third light source 113 for emitting near-infrared light. When the system switches between different partitions, by controlling the corresponding light-blocking plates of the first light-blocking plate 410, the second light-blocking plate 420, and the third light-blocking plate 430 to be inserted into the optical path, a faster and simpler wide-band ellipsometric measurement can be achieved.

[0055] Optionally, based on the above embodiments, the device further includes multiple beam combiners applicable to all wavelengths; the multiple beam combiners applicable to all wavelengths are configured to send the light beams emitted by multiple sub-light sources of different wavelengths into the optical path of the polarization component respectively.

[0056] For example, continue to refer to Figure 7 The wideband ellipsometric measurement device may also include a first beam combiner 510 and a second beam combiner 520 applicable to the entire band; the first beam combiner 510 and the second beam combiner 520 are both disposed at the intersection of the optical path between two of the first light-blocking plates 410, the second light-blocking plate 420 and the third light-blocking plate 430 and the polarization component 200.

[0057] It is understandable that when light is incident on the first beam combiner 510 or the second beam combiner 520 from any two directions, it can exit into the measurement optical path.

[0058] Optionally, based on the above embodiments, the first light source 111 is a xenon lamp, the second light source 112 is a deuterium lamp, and the third light source 113 is a halogen lamp.

[0059] The wideband ellipsometric measurement device provided by this utility model, by using the above-mentioned polarization components and further integrating multi-band light sources, enables the same instrument to quickly adapt to the measurement requirements of different films and different processes, with high system integration and strong measurement adaptability.

[0060] In summary, this embodiment of the invention fixes multiple polarizers for transmitting beams of different wavelengths in multiple zones, and uses a drive mechanism 240 to rotate the fixing member 210, thereby switching between different zones and achieving high extinction ratio polarization characteristics of 190–1700 nm in a single system. The use of a motor drive instead of manual replacement improves efficiency and online measurement capabilities. The multi-zone rotating polarizer structure is compact and can be directly integrated into existing ellipsometric measurement optical paths. The same instrument can be quickly adapted to the measurement needs of different film layers and processes.

[0061] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A polarization component, characterized in that, include: The fixture, multiple polarizers for transmitting beams of different wavelengths, and a drive mechanism for rotating the fixture. The fastener includes multiple partitions and openings; the multiple polarizers for transmitting beams of different wavelengths are respectively fixed to the multiple partitions; The opening is fixedly connected to the driving mechanism, and the multiple partitions surround the opening at equal intervals.

2. The polarization component according to claim 1, characterized in that, The plurality of polarizers for transmitting beams of different wavelengths include at least two of the following polarizers: a first polarizer for transmitting deep ultraviolet beams, a second polarizer for transmitting visible beams, and a third polarizer for transmitting near-infrared beams.

3. The polarization component according to claim 1, characterized in that, The plurality of partitions on the fixing member are annular partitions with threads on the inner surface, and the plurality of polarizers for transmitting beams of different wavelengths are installed on the plurality of partitions by threaded connection.

4. The polarization component according to claim 1, characterized in that, The drive mechanism is a hollow direct drive motor; the opening is directly connected to the shaft of the hollow direct drive motor.

5. The polarization component according to claim 2, characterized in that, The first polarizer is a MgF2 polarizer, the second polarizer is a quartz polarizer, and the third polarizer is a liquid crystal polymer polarizer.

6. A broadband ellipsometric measurement device, characterized in that, include: The light source, the polarization assembly according to any one of claims 1-5, the second rotating motor, the polarization analyzer, and the spectrometer; The second rotating motor is hollow, and a compensation waveplate is installed at the hollow position of the second rotating motor; The light beam emitted by the light source is converted into linearly polarized light by the polarization component, passes through the compensation waveplate and reaches the surface of the sample. The light reflected by the sample passes through the analyzer and enters the spectrometer.

7. The broadband ellipsometric measurement device according to claim 6, characterized in that, The light source includes multiple sub-light sources in different wavelength bands.

8. The broadband ellipsometric measurement device according to claim 7, characterized in that, The multiple sub-light sources of different wavelengths include at least two of the following sub-light sources: a first light source for emitting visible light beams, a second light source for emitting deep ultraviolet light beams, and a third light source for emitting near-infrared light beams.

9. The broadband ellipsometric measurement device according to claim 7, characterized in that, It also includes multiple light-blocking plates, each of which is used to block the light beam emitted by each of the sub-light sources.

10. The broadband ellipsometric measurement device according to claim 7, characterized in that, It also includes multiple beam combiners applicable to all wavelengths; The multiple beam combiners applicable to all wavelengths are configured to send the light beams emitted by the multiple sub-light sources of different wavelengths into the optical path of the polarization component.

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