Light path offset detection device and photoetching system

Abstract

The utility model provides a light path offset detection device and a photoetching system, the device comprises a light guider, a light amplifier, an image converter and an image display, the light guider guides light in a light path to the light amplifier; the light amplifier amplifies the light transmitted by the light guider and transmits the light to the image converter; the image converter converts the optical signal into an image signal; and the image display receives the image signal and displays an image. The optical path deviation detection device can determine whether the optical path deviates according to the image displayed by the image display, can quickly verify the adjustment result after the optical path is adjusted, can detect the optical path at any time without occupying the operation time of a machine, reduces the complexity of optical path deviation detection operation, optimizes the operation process, and improves the detection efficiency. And the time required for daily monitoring of the light path is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, and particularly relates to an optical path offset detection device and a lithography system. Background Art

[0002] When a wafer is exposed by a lithography machine, an offset of the optical path will cause abnormalities in the product. In order to ensure the stability of the product, it is necessary to regularly monitor the offset of the optical path to avoid the occurrence of defect problems.

[0003] The existing method for monitoring the optical path offset is to provide a wafer, perform coating, exposure, and development operations on the wafer, confirm the result through the developed wafer map, and then determine the optical path position according to the offset amount of the result.

[0004] The above monitoring method has a long process and requires the assistance of a coating and developing machine and a measuring machine. When the equipment is operating at saturation, it is very difficult to coordinate multiple devices to stop simultaneously to prepare for the optical path detection of the lithography machine.

[0005] In addition, the optical path offset may be caused by different focal positions of the optical path when the mercury lamp is replaced. Each time the mercury lamp is replaced, it is necessary to detect. The current monitoring method takes a long time and has a large production pressure, and cannot guarantee the equipment uptime. It cannot provide time for the engineering department to monitor the optical path offset detection by stopping the machine. However, if an optical path offset occurs, it will affect the product yield.

[0006] Moreover, adjusting the optical path and detecting the result of the optical path cannot be carried out simultaneously, and it is necessary to perform exposure and development before detecting whether the optical path is normal. If the optical path is abnormal, it is necessary to adjust and then perform exposure and development to verify the result. The monitoring method may need to be repeated multiple times, and the equipment uptime cannot be guaranteed. Summary of the Utility Model

[0007] The purpose of the utility model is to provide an optical path offset detection device and a lithography system, which can detect the optical path at any time without occupying the machine operation time, reduce the complexity of the optical path detection operation, optimize the operation process, and reduce the time required for daily optical path monitoring.

[0008] To solve the above technical problems, the utility model provides an optical path offset detection device, including: an optical path director, an optical amplifier, an image converter, and an image display; wherein,

[0009] The optical path director directs the light in the optical path to the optical amplifier;

[0010] The optical amplifier amplifies the light transmitted by the optical path director and transmits it to the image converter;

[0011] The image converter converts the optical signal into an image signal; and

[0012] The image display receives the image signal and displays an image.

[0013] Optionally, the light guide includes an objective lens.

[0014] Optionally, the optical amplifier includes a erecting lens.

[0015] Optionally, the image converter includes a CCD.

[0016] Optionally, the optical path offset detection device further includes a light deflector, which is located between the light guide and the optical amplifier, and the light deflector is used to deflect the light output from the light guide and input it into the optical amplifier.

[0017] Optionally, the light deflector includes a relay lens.

[0018] Optionally, the optical path offset detection device further includes an aperture stop, which is located between the optical amplifier and the image converter, and the aperture stop is used to limit the range of light incident on the image converter.

[0019] Correspondingly, the present utility model further provides a lithography system, including a lithography apparatus and the optical path offset detection device as described above, and the optical path offset detection device is used to detect the offset of the optical path in the lithography apparatus.

[0020] Optionally, the lithography apparatus includes a light source, a photomask, a lens group, and a wafer to be exposed. The light emitted by the light source passes through the photomask, and the lens group receives the light passing through the photomask and adjusts the deformation of the light, and presents the pattern on the photomask on the wafer.

[0021] Optionally, the light guide guides the light emitted from the lens group to the optical amplifier; the image display is used to display an image of the pattern on the photomask.

[0022] Compared with the prior art, the optical path offset detection device provided by the present utility model includes an optical waveguide, an optical amplifier, an image converter, and an image display. The optical waveguide guides the light in the optical path to the optical amplifier. The optical amplifier amplifies the light transmitted by the optical waveguide and transmits it to the image converter. The image converter converts the optical signal into an image signal. The image display receives the image signal and displays the image. The present utility model can determine whether there is an offset in the optical path according to the image displayed on the image display, can quickly verify the adjustment result after adjusting the optical path, can detect the optical path at any time without occupying the running time of the machine tool, and at the same time reduces the complexity of the optical path offset detection operation, optimizes the operation process, and reduces the time required for daily monitoring of the optical path.

[0023] In the lithography system provided by the present utility model, an optical path offset detection device is used to detect the offset of the lithography optical path. The operator no longer needs to detect the position of the optical path through complex processes such as coating, exposure, and development, saving the detection time, increasing the running time of the equipment, reducing the repeated operations in the process, and reducing the equipment loss rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Those of ordinary skill in the art will understand that the provided drawings are used to better understand the present utility model and do not limit the scope of the present utility model in any way. Among them:

[0025] Figure 1 is a schematic diagram of a reticle pattern.

[0026] Figure 2 is a schematic diagram of a normal pattern formed on a wafer.

[0027] Figure 3 is a schematic diagram of an abnormal pattern formed on a wafer when the optical path is offset upward.

[0028] Figure 4 is a schematic structural diagram of an optical path offset detection device provided by an embodiment of the present utility model.

[0029] Figure 5 is a schematic structural diagram of a lithography system provided by an embodiment of the present utility model.

[0030] DESCRIPTION OF REFERENCE NUMERALS:

[0031] 1 - Pattern; 2 - Alignment mark; 10 - Optical path offset detection device; 11 - Optical waveguide; 12 - Optical deflector; 13 - Optical amplifier; 14 - Aperture diaphragm; 15 - Image converter; 16 - Control system; 161 - Vision processor; 162 - CPU; 163 - Graphics card driver; 17 - Image display; 20 - Lithography apparatus; 21 - Light source; 22 - Reticle; 23 - Lens group; 24 - Wafer. Detailed Implementation Modes

[0032] The inventor encountered an anomaly during the wafer manufacturing process. Specifically, when the product was exposed using a lithography machine, surface anomalies were detected on the chips (dies) at fixed positions through a measurement device, and each wafer had fixed-chip anomalies. To address this issue, the process first adjusted the exposure and development parameters, but neither measure solved the problem. Subsequently, similar problems occurred when other layers of wafers were replaced. After that, the photomask was inspected and new photomasks were fabricated multiple times, yet similar problems still persisted. Then, the uniformity of the light intensity was detected in the equipment section, but no cause was identified. Subsequently, the optical path was inspected and it was found that the optical path was offset, and the alignment marks (marks) around the photomask pattern were also exposed on the wafer, resulting in anomalies at fixed positions on the wafer.

[0033] Figure 1 is a schematic diagram of the photomask pattern, Figure 2 is a schematic diagram of the normal pattern formed on the wafer, Figure 3 is a schematic diagram of the abnormal pattern formed on the wafer when the optical path is offset upward. Please refer to Figure 1 As shown, alignment marks 2 are provided around pattern 1 on the photomask for photomask alignment. Under normal circumstances, when using this photomask for exposure, pattern 1 is formed on the wafer, forming a pattern as shown in Figure 2 However, in the case where the optical path is offset upward, the lower pattern is not formed on the wafer, and the top alignment mark 2 is formed on the wafer, forming a pattern as shown in Figure 3 This results in anomalies on the wafer.

[0034] According to the description in the above background art, the method for detecting optical path offset is complex. However, to ensure the stability of the product, it is necessary to regularly monitor the optical path offset to avoid the occurrence of defect problems.

[0035] Based on the above problems, through research, the inventor provides an optical path offset detection device, including: an optical waveguide, an optical amplifier, an image converter, and an image display; wherein, the optical waveguide guides the light in the optical path to the optical amplifier; the optical amplifier amplifies the light transmitted by the optical waveguide and transmits it to the image converter; the image converter converts the optical signal into an image signal; the image display receives the image signal and displays the image.

[0036] Correspondingly, the present utility model also provides a lithography system, including a lithography device and the optical path offset detection device as described above, and the optical path offset detection device is used to detect the offset of the optical path in the lithography device.

[0037] The utility model can determine whether the optical path has an offset according to the image displayed on the image display, can quickly verify the adjustment result after adjusting the optical path, can detect the optical path at any time without occupying the operation time of the machine, and the operator does not need to detect the position of the optical path through complex processes such as glue coating, exposure, and development, reducing the complexity of the optical path offset detection operation, optimizing the operation process, reducing the time required for daily monitoring of the optical path, improving the operation time of the equipment at the same time, reducing the repeated operations in the process, and reducing the equipment damage rate.

[0038] To make the objectives, advantages and features of the utility model clearer, the following further describes the utility model in detail with reference to the drawings and specific embodiments. It should be noted that the drawings are in a very simplified form and not drawn to scale, only for the purpose of facilitating and clearly assisting in explaining the objectives of the embodiments of the utility model. In addition, the structures shown in the drawings are often part of the actual structures. In particular, the focus to be shown in each drawing is different, and sometimes different scales are used.

[0039] As used in the present utility model, the singular forms "a", "an" and "the" include plural objects unless the context clearly indicates otherwise. As used in the present utility model, the term "or" is generally used in the sense of including "and / or" unless the context clearly indicates otherwise. As used in the present utility model, the term "several" is generally used in the sense of including "at least one" unless the context clearly indicates otherwise. As used in the present utility model, the term "at least two" is generally used in the sense of including "two or more" unless the context clearly indicates otherwise. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", and "third" may explicitly or implicitly include one or at least two of such features.

[0040] Figure 4 is a schematic diagram of an optical path offset detection device provided by an embodiment of the present utility model. Please refer to Figure 4 As shown, the optical path offset detection device 10 provided by the embodiment of the present utility model includes an optical director 11, an optical amplifier 13, an image converter 15, and an image display 17. Among them, the optical director 11 directs the light in the optical path to the optical amplifier 13, and the optical path is the optical path that needs to be detected for offset. The optical amplifier 13 amplifies the light transmitted by the optical director 11 and transmits it to the image converter 15. The image converter 15 converts the optical signal into an image signal, and the image display 17 receives the image information and displays the image.

[0041] In the present utility model, it is possible to determine whether there is an optical path offset based on the image displayed by the image display 17. After adjusting the optical path, it is possible to quickly verify the adjustment result, and it is possible to check the optical path at any time without occupying the operation time of the machine tool. At the same time, the complexity of the optical path offset detection operation is reduced, the operation process is optimized, and the time required for daily monitoring of the optical path is reduced.

[0042] In an embodiment of the present utility model, the optical path offset detection device 10 further includes an optical deflector 12, and the optical deflector 12 is located between the optical guide 11 and the optical amplifier 13. The optical deflector 12 is configured to deflect the light output from the optical guide 11 and input it into the optical amplifier 13.

[0043] In an embodiment of the present utility model, the optical path offset detection device 10 further includes an aperture stop 14, and the aperture stop 14 is located between the optical amplifier 13 and the image converter 15. The aperture stop 14 is configured to limit the range of light incident on the image converter 15.

[0044] In an embodiment of the present utility model, the optical guide 11 includes an objective lens, the optical amplifier 13 includes a erecting lens, the image converter 15 includes a CCD (Charged Coupled Device), and the optical deflector 12 includes a relay lens, but is not limited thereto.

[0045] Specifically, the objective lens guides the light in the optical path to the relay lens, the relay lens deflects the light emitted from the objective lens and inputs it into the erecting lens, the erecting lens amplifies the light transmitted by the relay lens and transmits it to the CCD, the CCD converts the optical signal into an image signal, and the image display 17 receives the image signal and displays an image.

[0046] In an embodiment of the present utility model, the optical path offset detection device 10 further includes a control system 16, and the control system 16 is configured to receive the image signal transmitted by the image converter 15 and control the image display 17 to display an image. Exemplarily, the control system 16 includes a vision processor 161, a CPU (Central Processing Unit) 162, and a graphics card driver 163. The vision processor 161 is configured to receive the image signal transmitted by the image converter 15 and transmit the acquired image signal to the CPU 162. The CPU 162 is configured to process the image signal, and the graphics card driver 163 is configured to display the image signal processed by the CPU 162 on the image display 17.

[0047] The optical path offset detection device 10 provided by the present utility model can detect the offset of any optical path, and only needs to direct the light in the optical path to the optical path offset detection device 10. For example, the optical path offset detection device 10 can detect the optical path of a lithography device to determine whether there is an offset in the optical path of the lithography device, thereby avoiding defects on the wafer.

[0048] The optical path offset detection device 10 provided by the present utility model includes an optical director 11, an optical amplifier 13, an image converter 15, and an image display 17. The optical director 11 directs the light in the optical path to the optical amplifier 13. The optical amplifier 13 amplifies the light transmitted by the optical director 11 and transmits it to the image converter 15. The image converter 15 converts the optical signal into an image signal. The image display 17 receives the image signal and displays the image. The present utility model can determine whether there is an offset in the optical path according to the image displayed on the image display 17, can quickly verify the adjustment result after adjusting the optical path, can detect the optical path at any time without occupying the operation time of the machine tool, meanwhile reduces the complexity of the optical path offset detection operation, optimizes the operation process, and reduces the time required for daily monitoring of the optical path.

[0049] Correspondingly, the present utility model also provides a lithography system, including a lithography device and the optical path offset detection device as described above.

[0050] Figure 5 It is a schematic structural diagram of the lithography system provided by an embodiment of the present utility model. Please refer to Figure 5 As shown, the lithography system provided by the embodiment of the present utility model includes a lithography device 20 and an optical path offset detection device 10. The optical path offset detection device 10 is used to detect the offset of the optical path in the lithography device 20.

[0051] The lithography device 20 includes a light source 21, a reticle 22, a lens group 23, and a wafer 24 to be exposed. The emitted light of the light source 21 sequentially passes through the reticle 22 and the lens group 23 and irradiates onto the wafer 24. The lens group 23 receives the light passing through the reticle 22 and adjusts the deformation of the light, and presents the pattern on the reticle 22 on the wafer 24 to complete the exposure of the wafer 24. Exemplarily, the light source 21 can be a mercury lamp, and the lens group 23 can be a lens group composed of multiple lenses such as a trapezoidal mirror, a concave mirror, and a convex mirror.

[0052] The optical waveguide 11 guides the light passing through the lens group 23 in the optical path to the optical deflector 12. The optical deflector 12 deflects the light emitted from the optical waveguide 11 and inputs it into the optical amplifier 13. The optical amplifier 13 amplifies the light transmitted by the optical deflector 12 and transmits it to the image converter 15 through the aperture stop 14. The aperture stop 14 is used to limit the range of the light incident on the image converter 15. The image converter 15 converts the received optical signal into an image signal and transmits it to the control system 16. After receiving the graphic signal, the control system 16 controls the image display 17 to display an image.

[0053] In the present utility model, the optical waveguide 11 guides out the light passing through the lens group 23. The image converter 15 converts the optical signal into an image signal. The image display 17 displays the image of the pattern after passing through the lens group 23, and compares it with the pattern on the photomask 22, so that the deviation condition of the optical path can be clearly obtained. After adjusting the deviation of the optical path, the result of the adjustment can be quickly determined.

[0054] Currently, the devices or equipment on the market cannot make corresponding changes according to the actual situation. The lithography system provided by the present utility model can determine whether there is a deviation in the optical path according to the actual situation, quickly solve the problem of deviation, and avoid product defects caused by insufficient monitoring. There is no need to stop the coating and developing machine and the measuring machine to detect the deviation of the optical path. After the light source 21 is replaced, it can quickly detect whether the optical path is deviated, without affecting the normal production and manufacturing.

[0055] In this embodiment, the deviation of the optical path includes the deviation of the lenses in the lens group 23 and the deviation of the light emitted by the light source 21 to the photomask 22.

[0056] Currently, the devices on the market can only confirm the position of the lens group by projecting the image passing through the lens group 23 onto the wafer through coating, exposure and development. The present utility model extracts the image passing through the lens group 23 and displays the image in the lens group 23 on the image display 17 to determine whether there is a deviation. The operator no longer needs to detect the position of the optical path through complex processes such as coating, exposure and development. The present utility model simplifies the monitoring operation process, eliminates cumbersome steps, does not require a coating and developing machine and measuring equipment, reduces the repeated operations in the process, does not affect the running time of other equipment, reduces the dependence on other equipment, and optimizes the operation process. At the same time, it saves the detection time, increases the running time of the lithography equipment, and reduces the equipment loss rate.

[0057] In summary, the optical path offset detection device provided by the present utility model includes an optical waveguide, an optical amplifier, an image converter, and an image display. The optical waveguide guides the light in the optical path to the optical amplifier. The optical amplifier amplifies the light transmitted by the optical waveguide and transmits it to the image converter. The image converter converts the optical signal into an image signal, and the image display receives the image signal and displays the image. The present utility model can determine whether there is an offset in the optical path according to the image displayed on the image display, can quickly verify the adjustment result after adjusting the optical path, can detect the optical path at any time without occupying the operation time of the machine tool, and at the same time reduces the complexity of the optical path offset detection operation, optimizes the operation process, and reduces the time required for daily monitoring of the optical path.

[0058] In the lithography system provided by the present utility model, an optical path offset detection device is used to detect the offset of the lithography optical path. The operator no longer needs to detect the position of the optical path through complex processes such as coating, exposure, and development, saving the detection time, increasing the operation time of the equipment, reducing the repeated operations in the process, and reducing the equipment damage rate.

[0059] The above description is only a description of the preferred embodiments of the present utility model, and does not limit the scope of the rights of the present utility model in any way. Any person skilled in the art can make possible changes and modifications to the technical solution of the present utility model by using the methods and technical contents disclosed above without departing from the spirit and scope of the present utility model. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present utility model without departing from the content of the technical solution of the present utility model shall fall within the protection scope of the technical solution of the present utility model.

Claims

1. An optical path deviation detection device, characterized in that: include: A light guide, a light amplifier, an image converter and an image display; wherein, The light guide guides the light in the optical path to the optical amplifier; The optical amplifier amplifies the light transmitted by the light guide and transmits the amplified light to the image converter; The image converter converts the optical signal into an image signal; and The image display receives the image signal and displays an image; The optical amplifier further comprises an aperture stop, wherein the aperture stop is located between the optical amplifier and the image converter, and the aperture stop is used to limit the range of light incident on the image converter.

2. The optical path deviation detection device according to claim 1, characterized in that: The light guide includes an objective lens.

3. The optical path deviation detection device according to claim 1, characterized in that: The optical amplifier includes an erecting lens.

4. The optical path deviation detection device according to claim 1, characterized in that: The image converter includes a CCD.

5. The optical path deviation detection device according to any one of claims 1 to 4, characterized in that: The optical path deviation detection device further comprises a light redirector, which is located between the light guide and the optical amplifier and is used for redirecting the light output from the light guide to input into the optical amplifier.

6. The optical path deviation detection device according to claim 5, characterized in that: The light redirector includes a relay lens.

7. A photolithography system, characterized in that: The invention comprises a photolithography device and the optical path deviation detection device according to any one of claims 1 to 6, wherein the optical path deviation detection device is used to detect the deviation of the optical path in the photolithography device.

8. The photolithography system according to claim 7, characterized in that: The photolithography device includes a light source, a mask, a lens group and a wafer to be exposed. The light emitted by the light source passes through the mask. The lens group receives the light passing through the mask and adjusts the deformation of the light to present the pattern on the mask on the wafer.

9. The photolithography system according to claim 8, characterized in that: The light guide guides the light emitted from the lens group to the light amplifier; and the image display is used to display the image of the pattern on the mask.

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