Optical system and MOCVD (Metal Organic Chemical Vapor Deposition) online monitoring system

Abstract

The utility model discloses an optical system and an MOCVD online monitoring system, a first light source is used for emitting a first light beam with a first preset wavelength, the first light beam is collimated by a second positive lens, then enters a dichroscope, is reflected by the dichroscope, is converged by a first positive lens, and is projected to the surface of a test sample; the first light beam reflected by the test sample is projected back to the receiving surface of the first light source through the first positive lens, the dichroscope and the second positive lens; the second light source is used for emitting a second light beam with a second preset wavelength, after being collimated by the third positive lens, the second light beam enters the dichroscope, and after being transmitted by the dichroscope, the second light beam is converged by the first positive lens and projected to the surface of the test sample; the second light beam reflected by the test sample is projected back to the receiving surface of the second light source through the first positive lens, the dichroscope and the third positive lens; measurement of different requirements can be carried out by the same system, and the flexibility and the working efficiency of the MOCVD online monitoring system are improved.

Description

Technical Field

[0001] This application relates to the field of optical path technology, and in particular to an optical system and an online monitoring system for MOCVD. Background Technology

[0002] MOCVD (Metal-Organic Chemical Vapor Deposition) is a precision process used to manufacture semiconductor materials. MOCVD online monitoring systems are used to monitor the temperature, reflectivity, and warpage of the wafer in real time during the process, providing reliable temperature signals for temperature control of the wafer.

[0003] The optical paths included in current MOCVD online monitoring systems are difficult to apply quickly to single-wavelength or dual-wavelength monitoring, resulting in poor flexibility and low efficiency of MOCVD online monitoring systems. Utility Model Content

[0004] This application provides an optical system and an MOCVD online monitoring system, which solves the technical problem that the optical paths contained in the current MOCVD online monitoring system are difficult to quickly apply to single-wavelength monitoring or dual-wavelength monitoring, resulting in poor flexibility and low working efficiency of the MOCVD online monitoring system.

[0005] In view of this, this application provides an optical system comprising:

[0006] The first optical fiber module, the second optical fiber module, the dichroic mirror, and the first positive lens;

[0007] The first fiber optic module includes a first light source and a second positive lens;

[0008] The first light source emits a first beam of a first preset wavelength, which is collimated by the second positive lens, incident on the dichroic mirror, reflected by the dichroic mirror, converged by the first positive lens, and projected onto the surface of the test sample. The beam of the first beam reflected by the test sample is projected back to the receiving surface of the first light source through the first positive lens, the dichroic mirror, and the second positive lens.

[0009] The second fiber optic module includes a second light source and a third positive lens;

[0010] The second light source emits a second beam of a second preset wavelength, which is collimated by the third positive lens, incident on the dichroic mirror, transmitted through the dichroic mirror, converged by the first positive lens, and projected onto the surface of the test sample. The beam of the second beam reflected by the test sample is projected back to the receiving surface of the second light source through the first positive lens, the dichroic mirror, and the third positive lens.

[0011] The first preset wavelength and the second preset wavelength have different wavelength bands.

[0012] Preferably, both the first light source and the second light source contain multimode optical fibers.

[0013] Preferably, the focal length of the second positive lens is limited to the range of 5-10mm.

[0014] Preferably, the focal length of the third positive lens is limited to the range of 5-10mm.

[0015] Preferably, the first preset wavelength is 633 / 635nm.

[0016] Preferably, the second preset wavelength is 940 / 950nm.

[0017] Secondly, this utility model also provides an online monitoring system for MOCVD, which applies the optical system described in the first aspect.

[0018] As can be seen from the above technical solutions, the embodiments of this application use two independent optical fiber modules. Different optical fiber modules can be selected to work according to the test requirements. At the same time, by utilizing the different wavelength bands of the two optical fiber modules, it is possible to quickly apply to single-wavelength monitoring or dual-wavelength monitoring. In addition, the focal length of the different positive lenses contained in the two optical fiber modules can be limited according to the test requirements, so as to realize the same system to perform measurements for different needs, thereby improving the flexibility and working efficiency of the MOCVD online monitoring system. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of an optical system;

[0020] Figure 2 This is a schematic diagram of an online monitoring system for MOCVD. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0022] In the description of the embodiments of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] like Figure 1 As shown, this application provides an optical system, including:

[0024] The first optical fiber module 10, the second optical fiber module 20, the dichroic mirror 50, and the first positive lens 30;

[0025] The first optical fiber module 10 includes a first light source 11 and a second positive lens 12;

[0026] The first light source 11 emits a first beam of a first preset wavelength. After being collimated by the second positive lens 12, the beam is incident on the dichroic mirror 50. After being reflected by the dichroic mirror 50, the beam is converged by the first positive lens 30 and projected onto the surface of the test sample 40. The beam of the first beam after being reflected by the test sample 40 is projected back to the receiving surface of the first light source 11 through the first positive lens 30, the dichroic mirror 50, and the second positive lens 12.

[0027] The second fiber optic module 20 includes a second light source 21 and a third positive lens 22;

[0028] The second light source 21 emits a second beam of a second preset wavelength. After being collimated by the third positive lens 22, the beam is incident on the dichroic mirror 50. After being transmitted through the dichroic mirror 50, the beam is converged by the first positive lens 30 and projected onto the surface of the test sample 40. The beam of the second beam reflected by the test sample 40 is projected back to the receiving surface of the second light source 21 through the first positive lens 30, the dichroic mirror 50 and the third positive lens 22.

[0029] The first preset wavelength and the second preset wavelength have different bands.

[0030] It should be noted that the focal length range of the second positive lens 12 and the third positive lens 22 can be adjusted according to the test distance, the type of test sample 40, and the surface reflection efficiency. The implementation method is to replace the lens with a different focal length. By replacing the positive lens with a different focal length, the module can be replaced. Single-wavelength monitoring can be realized, or dual-wavelength modularization can be realized by replacing the module.

[0031] In some embodiments, the focal length of the second positive lens 12 is defined as 5-10 mm, and the focal length of the third positive lens 22 is defined as 5-10 mm.

[0032] It is understood that, since the optical system provided in this application embodiment has two independent fiber optic modules, and the wavelengths of the light sources of the two fiber optic modules are different, the system can be modularized and replaceable, and different measurement requirements can be achieved by the same system as needed.

[0033] In some embodiments, both the first light source 11 and the second light source 21 include multimode optical fibers.

[0034] The first preset wavelength of the multimode fiber corresponding to the first light source 11 is 633 / 635nm, NA=0.22 / 0.12, and the multimode fiber can emit and receive beams of 633 / 635nm wavelength.

[0035] The second preset wavelength of the multimode fiber corresponding to the second light source 21 is 940 / 950nm, and NA=0.22 / 0.12; the multimode fiber can emit and receive beams of 940 / 950nm wavelength.

[0036] In some embodiments, the focal length of the first positive lens 30 can be replaced within the range of 20-40mm to achieve collimation and focusing of 633 / 635nm and 940 / 950nm beams.

[0037] In some embodiments, the dichroic mirror 50 reflects a 633 / 635nm light beam and transmits a 940 / 950nm light beam.

[0038] The optical path operation process of the optical system provided in this application embodiment is as follows:

[0039] The multimode fiber corresponding to the first light source 11 emits a 633 / 635nm wavelength light beam at a certain angle. After being collimated by the second positive lens 12, it is reflected by the dichroic mirror 50 and then collimated or focused a second time by the first positive lens 30. After being collimated or focused a second time, the light beam is projected onto the surface of the test sample 40, where it is scattered or nearly totally internally reflected. The reflected light is collected and collimated by the first positive lens 30. After collimation, the light beam is reflected a second time by the dichroic mirror 50, and the reflected 633nm / 635nm light beam is focused a second time by the second positive lens 12 onto the receiving surface of the multimode fiber corresponding to the first light source 11.

[0040] The multimode fiber corresponding to the second light source 21 emits a 940 / 950nm wavelength light beam at a certain angle. After being collimated by the third positive lens 22, it is transmitted through the dichroic mirror 50 and then collimated or focused a second time by the first positive lens 30. After being collimated or focused a second time, the light beam is projected onto the surface of the test sample 40, where it is scattered or nearly totally internally reflected. The reflected light is collected and collimated by the first positive lens 30. After collimation, the light beam is transmitted a second time through the dichroic mirror 50. The transmitted 940 / 950nm light beam is then focused a second time by the third positive lens 22 onto the receiving surface of the multimode fiber corresponding to the second light source 21.

[0041] It should be noted that the embodiments of this application use two independent optical fiber modules. Different optical fiber modules can be selected for operation according to the test requirements. At the same time, by utilizing the different wavelength bands of the two optical fiber modules, it is possible to quickly apply to single-wavelength monitoring or dual-wavelength monitoring. Furthermore, the focal length of the different positive lenses contained in the two optical fiber modules can be limited according to the test requirements, so as to enable the same system to perform measurements for different needs, thereby improving the flexibility and working efficiency of the MOCVD online monitoring system.

[0042] This application also provides an online MOCVD monitoring system 100, which uses the optical system 200 in the above embodiments.

[0043] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An optical system characterized by comprising: Comprising: a first optical fiber module, a second optical fiber module, a dichroic mirror and a first positive lens; the first optical fiber module comprises a first light source and a second positive lens; the first light source is configured to emit a first light beam of a first preset wavelength, which is collimated by the second positive lens, is incident on the dichroic mirror, is reflected by the dichroic mirror, is converged by the first positive lens and is projected onto the surface of a test sample, and the light beam reflected by the test sample is projected back to the receiving surface of the first light source through the first positive lens, the dichroic mirror and the second positive lens; the second optical fiber module comprises a second light source and a third positive lens; the second light source is configured to emit a second light beam of a second preset wavelength, which is collimated by the third positive lens, is incident on the dichroic mirror, is transmitted by the dichroic mirror, is converged by the first positive lens and is projected onto the surface of the test sample, and the light beam reflected by the test sample is projected back to the receiving surface of the second light source through the first positive lens, the dichroic mirror and the third positive lens; wherein the wavelength bands of the first preset wavelength and the second preset wavelength are different.

2. The optical system of claim 1, wherein The first light source and the second light source each comprise a multimode optical fiber.

3. The optical system of claim 1, wherein The focal length of the second positive lens is limited to the range of 5-10 mm.

4. The optical system of claim 1, wherein The focal length of the third positive lens is limited to the range of 5-10 mm.

5. The optical system of claim 1, wherein The first preset wavelength is 633 / 635 nm.

6. The optical system of claim 1, wherein The second preset wavelength is 940 / 950 nm.

7. A MOCVD on-line monitoring system, characterized in that, Use the optical system according to any one of claims 1-6.

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