Back alignment device with annular illumination

Abstract

The utility model discloses a back alignment device with annular lighting, which is used for determining accurate positioning of a substrate placed on a loading part, a light hole is arranged on the loading part corresponding to a back alignment mark of the substrate, and the back alignment device comprises a back alignment device and a second lighting part, the second lighting part is arranged on the loading part and located below the light transmitting hole, a through hole is formed in the second lighting part, and the through hole and the light transmitting hole are coaxially arranged; the back alignment device comprises a lens cone, one end of the lens cone is connected with an imaging part, the other end of the lens cone is connected with a light path turning part, a first illumination part is further arranged on the lens cone and located between the imaging part and the light path turning part, and the light path turning part is located below a second illumination part. According to the utility model, a more uniform and stable illumination effect is achieved, and meanwhile, the requirements of alignment application scenes of base materials made of different materials are met; in addition, the time for debugging the focal plane is short, and the product yield is improved while the operation stability of the alignment device is improved.

Description

Technical Field

[0001] This utility model relates to the field of direct-write lithography technology, and in particular to a back-side alignment device with ring illumination. Background Technology

[0002] Currently, affected by the ongoing global chip shortage, the chip issue has received widespread attention. In chip manufacturing, photolithography is a crucial step. Photolithography technology is mainly divided into mask lithography and direct-write lithography. Direct-write lithography, also known as maskless lithography, refers to a computer-controlled high-precision beam of light being focused and projected onto a substrate surface coated with photosensitive material, allowing for direct scanning and exposure without a mask. Because direct-write lithography can flexibly transfer different patterns, the process is relatively simple and low-cost, and it is widely used in the pattern fabrication of circuit boards, semiconductor devices, and displays.

[0003] In existing technologies, during direct-write lithography, the back alignment device typically uses a camera (imaging unit), a telecentric lens (lens barrel), and a rotating mirror (optical path deflection unit) combined with coaxial light to determine the position of the back alignment mark on the substrate to be processed. Finally, the position parameters of the substrate are calculated for lithography. However, the aforementioned coaxial light is more suitable for positioning and detection of substrates with extremely high reflectivity, such as metals, glass, and wafers; but for other substrates with low reflectivity, such as copper-clad laminates, its accuracy and clarity during positioning and detection are poor.

[0004] In addition, in the focal plane adjustment stage of the back alignment device in the existing technology, the back alignment device mainly relies on the experience of the debugging personnel to manually adjust the position of the back alignment device up and down to find the focal plane position. This requires a high level of experience from the debugging personnel and takes a long time, which is ultimately not conducive to the stability of the back alignment device operation. Utility Model Content

[0005] To solve the above-mentioned technical problems, this utility model provides a back alignment device with ring lighting.

[0006] The technical solution of this utility model is:

[0007] A back alignment device with ring illumination for determining the precise positioning of a substrate placed on a loading section, wherein the loading section has a light-transmitting hole at the back alignment mark corresponding to the substrate, characterized in that it includes a back alignment device and a second illumination section.

[0008] The second lighting part is disposed on the loading part and located below the light-transmitting hole, and the second lighting part is provided with a through hole, which is coaxially arranged with the light-transmitting hole;

[0009] The back alignment device includes a lens barrel, one end of which is connected to an imaging unit and the other end of which is connected to a light path reversing unit. A first illumination unit is also provided on the lens barrel between the imaging unit and the light path reversing unit, and the light path reversing unit is located below the second illumination unit.

[0010] Furthermore, the lens barrel is connected to the drive end of the Z-axis moving module, and the Z-axis moving module is detachably connected to the loading part;

[0011] The Z-axis moving module drives the back alignment device to move closer to or further away from the second lighting unit along the Z-axis direction.

[0012] Furthermore, the light emitted by the second illumination unit is a ring-shaped illumination beam.

[0013] Furthermore, the second lighting unit includes a cylindrical mounting base, with the through hole located at the central axis of the mounting base; an annular mounting surface is formed on the inner wall of the mounting base, extending towards the outer diameter of the through hole, and a plurality of annular lighting sources are spaced apart on the mounting surface.

[0014] Furthermore, the top surface of the mounting surface facing the light-transmitting hole is a flared, inclined surface, and several of the annular lighting sources are spaced apart on the inclined surface.

[0015] Furthermore, the light color of each of the aforementioned annular lighting sources may be the same or different.

[0016] Furthermore, the brightness of each of the aforementioned annular lighting sources may be the same or different.

[0017] Furthermore, the angle between each of the aforementioned annular lighting sources and the mounting surface may be the same or different.

[0018] Furthermore, a multi-axis motion table is detachably connected below the loading section, and an accommodating space is provided between the multi-axis motion table and the loading section, with the back alignment device located within the accommodating space.

[0019] The beneficial technical effects of this utility model are:

[0020] Compared with the prior art, this utility model provides a second lighting unit below the light-transmitting hole of the loading part. On the one hand, the light emitted by the second lighting unit is a ring-shaped lighting beam, which can evenly illuminate the substrate to be processed from various angles, effectively avoiding the problem of light concentrating on a certain point and achieving a more uniform and stable lighting effect. On the other hand, the second lighting unit is provided with several ring-shaped lighting sources at intervals, which can select different light brightness, light color and light angle according to the different materials of the substrate to be processed, so as to meet the alignment application requirements of different substrate materials.

[0021] In addition, the back alignment device of this utility model is also equipped with a Z-axis moving module, which shortens the adjustment time of the focal plane, makes it more quick and convenient to find the focal plane position, improves the operational stability of the alignment device, and ultimately improves the product yield. Attached Figure Description

[0022] Figure 1 These are schematic diagrams showing the cooperation relationship between the present invention and the loading part and the base in four groups;

[0023] Figure 2 yes Figure 1 A schematic diagram from another angle after removing the substrate;

[0024] Figure 3 This is a schematic diagram showing the cooperation relationship between this utility model and the loading part;

[0025] Figure 4 This is a schematic diagram of the second lighting part of this utility model.

[0026] in:

[0027] 000-Base, 100-Loading part, 101-Light transmission hole; 200-Back alignment device, 201-Lens barrel, 202-Imaging part, 203-Optical path turning part, 204-First illumination part; 300-Second illumination part, 301-Mounting base, 302-Through hole, 303-Mounting surface; 400-Z-axis moving module, 500-Multi-axis motion stage. Detailed Implementation

[0028] In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0029] like Figures 1-4 As shown, this utility model provides a back alignment device with ring illumination, which is applied to a direct-write lithography device to determine the precise position of a substrate 000 placed on a loading section 100.

[0030] The substrate 000 has a back alignment mark on its back side. The substrate 000 to be processed is placed on the loading part 100. The loading part 100, as shown in this invention, has a light-transmitting hole 101 at each of its four corners, and the position of each light-transmitting hole 101 corresponds to the back alignment mark on the substrate 000. In actual use, the position of the light-transmitting hole 101 on the loading part 100 can be set according to the position and number of the back alignment marks on the substrate 000. The size of each light-transmitting hole 101 is compatible with the size of the back alignment mark and the field of view of the first illumination part 204 and the second illumination part 300.

[0031] A multi-axis motion table 500 is detachably connected below the loading part 100, and an accommodating space is provided between the multi-axis motion table 500 and the loading part 100. The rear alignment device with ring lighting of this utility model is wholly or partially located in the accommodating space. The multi-axis motion table 500 can drive the loading part 100 and the rear alignment device with ring lighting of this utility model to achieve at least three degrees of freedom of movement.

[0032] The present invention provides a back alignment device with ring lighting, comprising a back alignment device 200 and a second lighting unit 300.

[0033] The second lighting unit 300 is detachably mounted on the loading unit 100 and is located below each light-transmitting hole 101.

[0034] Specifically, the second lighting unit 300 includes a cylindrical mounting base 301 with a plurality of mounting holes. Each mounting hole of the mounting base 301 is detachably mounted to the loading unit 100 by screw fasteners. A through hole 302 is provided at the central axis of the mounting base 301. The through hole 302 is coaxially arranged with the light-transmitting hole 101, and their inner diameters are compatible to allow light from the first lighting unit 204 described below to pass through and illuminate the alignment mark on the back side. An annular mounting surface 303 is formed on the inner wall of the mounting base 301 and extends towards the outer diameter of the through hole 302. The mounting surface 303 facing the top surface of the light-transmitting hole 101 is a flared slope. A plurality of annular lighting sources (not shown) are installed at intervals on the slope of the mounting surface 303.

[0035] On the one hand, the light emitted by each annular illumination source is a circular illumination beam, ensuring that the beam can evenly illuminate the back alignment mark on the substrate from various angles, effectively avoiding the problem of beam concentration at a single point. On the other hand, to make the back alignment device of this invention more suitable for substrate materials with low reflectivity, ensuring that the intensity of reflected light after illumination meets the imaging and positioning conditions of the back alignment device 200, the color, light intensity, or installation angle of each annular illumination source can be selected according to the material of the substrate to be processed in actual production, without any particular restrictions. That is, the color of each annular illumination source can be the same or different, the light intensity of each annular illumination source can be the same or different, and the angle at which it is installed on the inclined surface of the mounting surface 303 can also be the same or different.

[0036] The back alignment device 200 includes a T-shaped lens barrel 201. One end of the lens barrel 201 is connected to an imaging unit 202 in the horizontal direction, and the other end is connected to an optical path deflection unit 203. The optical path deflection unit 203 is located below the second illumination unit 300. A first illumination unit 204 is connected to the middle of the lens barrel 201. The imaging unit 202 can be a CCD camera module, the first illumination unit 204 is a coaxial light source, and the optical path deflection unit 203 is prior art and will not be described in detail here.

[0037] To facilitate the back alignment device 200 to move up and down relative to the back alignment mark and thus quickly adjust the focal plane, a Z-axis moving module 400 with the driving direction set along the Z direction is also connected to the back alignment device 200.

[0038] Specifically, the lens barrel 201 is connected to the drive end of the Z-axis moving module 400, and the fixed end of the Z-axis moving module 400 is detachably connected to the loading part 100 via a connecting plate (not shown) and a bolt locking member (not shown). The Z-axis moving module 400 drives the back alignment device 200 to move upward toward the back alignment mark or downward away from the back alignment mark. Preferably, the Z-axis moving module 400 can be electrically connected to the control system to further improve its efficiency in driving the back alignment device 200 to quickly adjust the focal plane.

[0039] The operation process of this utility model is as follows:

[0040] 1) Application of the first lighting section 204:

[0041] During back alignment, when the substrate 000 to be processed is a material with high reflectivity, the second illumination unit 300 is turned off, and the first illumination unit 204 is activated as a coaxial light source to generate an illumination beam. The illumination beam is irradiated onto the back alignment mark on the back side of the substrate 000 through the optical path deflection unit 203, the through hole 302, and the light transmission hole 101. The reflected beam from the back alignment mark is then transmitted to the imaging unit 202 through the light transmission hole 101, the through hole 302, and the optical path deflection unit 203. At the same time, the Z-axis moving module 400 drives the optical path deflection unit 203 to move upward or downward relative to the back alignment mark, quickly finding the focal plane position. Thus, the imaging unit 202 captures a clear production image of the back alignment mark. The control device performs data analysis based on the image to determine the position coordinates of the back alignment mark, thereby calculating the position parameters of the substrate 000. Then, the control device adjusts the photolithography pattern based on the position of the substrate 000, so that the pattern beam is accurately projected onto the surface of the substrate 000 to be processed.

[0042] 2) Application of the second lighting unit 300:

[0043] During back-side alignment, when the substrate 000 to be processed is a material with low reflectivity, and the intensity of the reflected beam after being illuminated by the first illumination unit 204 is insufficient to meet the imaging and positioning conditions of the back-side alignment device 200, the first illumination unit 204 is turned off. Based on the material properties of the substrate 000, the color and light intensity of the ring-shaped illumination source on the second illumination unit 300 are selected first, and then the second illumination unit 300 is activated to generate a ring-shaped illumination beam. The ring-shaped illumination beam shines through the light-transmitting hole 101 onto the back-side alignment mark on the back of the substrate 000. The reflected beam from the back-side alignment mark then... The light is transmitted to the imaging unit 202 through the light-transmitting hole 101, the through hole 302, and the light path turning part 203. At the same time, the Z-axis moving module 400 drives the light path turning part 203 to move upward or downward relative to the back alignment mark, quickly finding the focal plane position. Thus, the imaging unit 202 captures a clear production image of the back alignment mark. The control device performs data analysis based on the image to determine the position coordinates of the back alignment mark, thereby calculating the position parameters of the substrate 000. Then, the control device adjusts the photolithography pattern based on the position of the substrate 000, so that the pattern beam is accurately projected onto the surface of the substrate 000 to be processed.

[0044] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A back-side alignment device with ring illumination for determining the precise positioning of a substrate placed on a loading section (100), wherein the loading section (100) has a light-transmitting hole (101) corresponding to a back-side alignment mark on the substrate, characterized in that, Includes a back alignment device (200) and a second illumination unit (300); The second lighting part (300) is provided on the loading part (100) and located below the light-transmitting hole (101), and the second lighting part (300) is provided with a through hole (302), which is coaxially arranged with the light-transmitting hole (101); The back alignment device (200) includes a lens barrel (201), one end of which is connected to an imaging unit (202) and the other end of which is connected to a light path turning part (203). A first illumination part (204) is also provided on the lens barrel (201) and located between the imaging unit (202) and the light path turning part (203), and the light path turning part (203) is located below the second illumination part (300).

2. The back-side alignment device with ring illumination according to claim 1, characterized in that, The lens barrel (201) is connected to the drive end of the Z-axis moving module (400), and the Z-axis moving module (400) is detachably connected to the loading part (100). The Z-axis moving module (400) drives the back alignment device (200) to move closer to or further away from the second lighting unit (300) along the Z-axis direction.

3. A back-side alignment device with ring illumination according to claim 1, characterized in that, The light emitted by the second illumination unit (300) is a ring-shaped illumination beam.

4. A back-side alignment device with ring illumination according to claim 3, characterized in that, The second lighting unit (300) includes a cylindrical mounting base (301), and the through hole (302) is located at the central axis of the mounting base (301); on the inner wall of the mounting base (301), an annular mounting surface (303) extends towards the outer diameter of the through hole (302) to form a ring-shaped mounting surface (303), and a plurality of annular lighting sources are spaced apart on the mounting surface (303).

5. A back-side alignment device with ring illumination according to claim 4, characterized in that, The top surface of the mounting surface (303) facing the light-transmitting hole (101) is a flared inclined surface, and several of the annular lighting sources are spaced apart on the inclined surface.

6. A back-side alignment device with ring illumination according to claim 4, characterized in that, The light from each of the aforementioned annular lighting sources may be the same or different colors.

7. A back-side alignment device with ring illumination according to claim 4, characterized in that, The brightness of each of the aforementioned annular lighting sources may be the same or different.

8. A back-side alignment device with ring illumination according to claim 4, characterized in that, The angle between each of the ring-shaped lighting sources and the mounting surface (303) may be the same or different.

9. A back-side alignment device with ring illumination according to claim 1, characterized in that, The loading section (100) is detachably connected to a multi-axis motion table (500) below, and a receiving space is provided between the multi-axis motion table (500) and the loading section (100), and the back alignment device (200) is located in the receiving space.

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