Mask alignment jig

Abstract

The application relates to the technical field of semiconductor photoetching, in particular to a mask plate alignment tool. The mask plate alignment tool comprises a fixed base, a substrate placement area for placing a target substrate and a mask plate containing area for placing a mask plate are arranged on the fixed base; a target pattern to be developed is arranged on the mask plate; an adjusting and fixing assembly is connected with the fixed base, and the adjusting and fixing assembly is in abutment with the mask plate; the adjusting and fixing assembly is used for adjusting the mask plate to a desired position and fixing the mask plate at the desired position; when the mask plate is at the desired position, the target pattern is located directly above the substrate placement area. The tool provided by the application can realize micron-level pattern copying precision on a target substrate at a low cost, and the structure is simple and convenient to use.

Description

Technical Field

[0001] This application relates to the field of semiconductor lithography technology, specifically to a mask alignment tool. Background Technology

[0002] Photolithography is an indispensable process in modern semiconductor manufacturing. It enables the batch, non-contact, and high-precision replication of micron-level patterns by shining light onto a substrate (a smooth, thin glass surface coated with photoresist). It is widely used in the manufacture of circuit boards, microchips, display filters, microelectromechanical systems, etc., and is a cornerstone technology of modern technology industry.

[0003] To ensure the accuracy of the replicated pattern, the photomask needs to be precisely aligned with the glass coated with photoresist. Current technologies typically require expensive optical alignment systems, which are costly and difficult to widely adopt, resulting in high production costs and low production efficiency. Utility Model Content

[0004] The purpose of this application is to provide a mask alignment fixture that can achieve micron-level pattern replication accuracy on a target substrate at a lower cost.

[0005] To achieve the above objectives, this application provides a mask alignment fixture, comprising: a fixed base, wherein the fixed base is provided with a substrate placement area for placing a target substrate and a mask receiving area for placing a mask; the mask is provided with a target pattern to be developed; an adjusting and fixing component, the adjusting and fixing component being connected to the fixed base and abutting against the mask; for adjusting the mask to a desired position and fixing the mask at the desired position, wherein when the mask is at the desired position, the target pattern is located directly above the substrate placement area.

[0006] In this embodiment, the fixed base includes: a fixed base plate, the mask receiving area is disposed on the top surface of the fixed base plate, and the substrate placement area is located within the mask receiving area; four side plates, the four side plates are arranged around the fixed base plate, and the four side plates are respectively fixedly connected to the fixed base plate, with the surface of any side plate being perpendicular to the surface of the fixed base plate; the side plates are also provided with connecting and fixing parts for connecting the adjusting and fixing components.

[0007] In this embodiment of the application, the substrate placement area is located in the middle of the mask accommodating area; within the mask accommodating area, substrate height blocks of the same height as the target substrate are respectively provided on both sides of the substrate placement area.

[0008] In this embodiment, the four side plates include a first side plate with two mutually perpendicular surfaces and a second side plate with two mutually perpendicular surfaces; the connecting and fixing part includes: a through hole and a first fixing hole on the first side plate, the axis of the through hole being perpendicular to the axis of the first fixing hole, the fixing hole communicating with the through hole, and the axis of the through hole being parallel to the surface of the fixing base plate; a second fixing hole on the second side plate, the axis of the second fixing hole being parallel to the surface of the fixing base plate; the adjusting and fixing assembly includes: a pin shaft, the pin shaft passing through the through hole, one end of which abuts against the mask plate; a micro-head, the micro-head... The end of the probe of the micrometer head abuts against the end of the pin away from the mask plate; the probe and the pin are coaxially arranged; the micrometer head fixing component is fixedly connected to the mounting sleeve of the micrometer head; the pin is threadedly connected to the first fixing hole, and one end of the pin can pass through the first fixing hole and abut against the pin that passes through the through hole; the spring set screw passes through the second fixing hole, and the inner wall of the second fixing hole is provided with an internal thread that matches the external thread of the spring set screw, and the spring set screw is threadedly connected to the second fixing hole; the tip of the spring set screw abuts against the mask plate.

[0009] In this embodiment of the application, the micrometer head fixing component includes: a fixing block, the fixing block having a mounting hole for fixing the micrometer head, the mounting sleeve of the micrometer head passing through the fixing hole, the mounting sleeve of the micrometer head being fixedly connected to the fixing block, and the fixing block being fixedly connected to the first side plate.

[0010] In this embodiment of the application, the mask alignment fixture further includes a protective strip, which has an adapter hole that is adapted to the pin or spring screw. The protective strip is arranged around the periphery of the four side plates and is used to cover the pin or spring screw exposed on the side plates.

[0011] In this embodiment, the substrate placement area is rectangular, and the fixing base further includes: a plurality of limiting bosses distributed on the top surface of the fixing base plate, the inner sidewall extension lines of the plurality of limiting bosses forming two adjacent sides of the substrate placement area; the limiting bosses are used to abut against the target substrate and to restrict the target substrate within the substrate placement area; and a limiting member detachably connected to the fixing base plate, the limiting member being located near the other two adjacent sides of the substrate placement area and used to cooperate with the limiting bosses to fix the position of the target substrate.

[0012] In this embodiment, the limiting member includes a magnetic block; the fixed base plate is provided with a plurality of magnetic grooves adapted to the magnetic block, and the plurality of magnetic grooves are distributed near the other two adjacent sides of the substrate placement area.

[0013] In this embodiment of the application, the substrate placement area of ​​the fixed base plate is also reserved with negative pressure adsorption holes for connecting to the negative pressure adsorption device.

[0014] The solution provided in this application has at least the following beneficial effects: 1) High alignment accuracy: In this application, a high-precision adjustment and fixing component, including a micrometer head, is used to adjust and position the mask, enabling the target pattern on the mask to be aligned with the target substrate at the micrometer level. Simultaneously, to reduce light refraction errors, the mask is directly contacted with the target substrate before fine-tuning its position. 2) High alignment efficiency: When adjusting the mask position, it is necessary to ensure the mask can move in four directions. In this application, spring-loaded screws and pins that abut against the micrometer head probe are respectively set on opposite sides of the mask. The micrometer head, located on two adjacent side plates, allows for position adjustment in four directions. In actual operation, the micrometer head probe can be used to push the mask away from the micrometer head's cylinder. During this process, the spring-loaded screw on the opposite side of the micrometer head is further compressed. When the micrometer head probe leaves the pin, the mask, under the rebound of the spring-loaded screw on the opposite side, pushes the pin back into contact with the micrometer head probe, thus achieving position adjustment in two directions. 3) It has a simple structure, is easy to install, and uses readily available and inexpensive materials. It can be reused repeatedly.

[0015] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings: Figure 1 A schematic diagram of the mask alignment fixture is shown. Figure 2 Schematic illustration Figure 1 A magnified view of a section at point A in the middle; Figure 3 A schematic diagram illustrating the installation of the mask is shown. Figure 4 A schematic top view of the mask alignment fixture is shown. Figure 5 The diagram illustrates a bottom view of the mask alignment fixture.

[0017] Explanation of reference numerals in the attached figures 1. Fixed base plate; 11. Mask receiving area; 12. Negative pressure adsorption hole; 2. Side plate; 21. First side plate; 22. Second side plate; 3. Pin; 4. Micrometer head; 5. Fixing block; 6. Spring set screw; 7. Substrate leveling block; 8. Limiting boss; 9. Magnetic groove; 10. Magnetic block; 20. Protective strip; 30. Magnet; 100. Mask; 200. Target substrate. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0019] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0020] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0021] Example 1

[0022] like Figure 1As shown, this application provides a mask alignment fixture, which includes: a fixed base, the fixed base having a substrate placement area for placing a target substrate 200 and a mask receiving area 11 for placing a mask 100; the mask 100 having a target pattern to be developed; an adjustment and fixing component, the adjustment and fixing component being connected to the fixed base and abutting against the mask 100; for adjusting the mask 100 to a desired position and fixing the mask 100 in the desired position, wherein when the mask 100 is in the desired position, the target pattern is located directly above the substrate placement area.

[0023] Specifically, the mounting base includes: A fixed base plate 1 is provided, and a mask receiving area 11 is provided on the top surface of the fixed base plate 1, such as... Figure 3 The recessed area shown is slightly recessed, and the substrate placement area is located within the mask accommodating area 11; the presence of the mask accommodating area 11 can be used for initial positioning of the mask 100. Taking a rectangular substrate placement area as an example (including right-angled rectangles and rounded rectangles), in this embodiment, the substrate placement area (neither a groove nor a boss) is not directly reflected on the fixed base plate 1. Its size is mainly reflected by the size of the target substrate 200 itself (which can be adaptively varied within a certain size range), and its position is limited by the limiting boss 8 and the limiting member.

[0024] Four side plates 2 are arranged around the fixed base plate 1, and each side plate 2 is fixedly connected to the fixed base plate 1. The surface of any side plate 2 is perpendicular to the surface of the fixed base plate 1, and there are no gaps between adjacent side plates 2. The four side plates 2 are connected in sequence. The side plates 2 are also provided with connecting and fixing parts for connecting the adjustment and fixing components. In this embodiment, the main function of the side plates 2 is to fix the adjustment and fixing components to facilitate the adjustment of the position of the mask plate 100.

[0025] In this embodiment, for ease of distinction, the four side plates 2 are divided into two groups: a first side plate 21 with two mutually perpendicular surfaces and a second side plate 22 with two mutually perpendicular surfaces, i.e., the two first side plates are adjacent and perpendicular, and the two second side plates 22 are adjacent and perpendicular. The aforementioned connecting and fixing part includes: a through hole and a first fixing hole provided on the first side plate 21, and a second fixing hole provided on the second side plate 22; wherein, the axis of the through hole is perpendicular to the axis of the first fixing hole, the fixing hole communicates with the through hole, and the axis of the through hole is parallel to the surface of the fixing base plate 1; the axis of the second fixing hole is parallel to the surface of the fixing base plate 1.

[0026] Specifically, the adjusting and fixing components include: A pin 3 passes through the through hole, with one end abutting against the mask 100 and the other end abutting against the end of the probe of the micrometer head 4. By adjusting the extension and retraction of the probe, the mask 100 can be moved axially along the pin 3. The reason for not directly using the probe to move the mask 100 is that the micrometer head 4 needs to be removed during the subsequent development process, and the mask 100 still needs to be fixed after removal. The fixing components used to fix the mask 100 also include a pin, which is threaded into the first fixing hole. One end of the pin passes through the first fixing hole and tightly abuts against the pin 3 passing through the through hole, thus fixing the pin 3. After fixing the pin 3, the micrometer head 4 is removed.

[0027] The measuring rod of the differential head 4 is coaxially arranged with the pin 3; preferably, the measuring rod and the pin 3 have the same diameter and length to ensure that the pin 3 is subjected to uniform force.

[0028] A micrometer head fixing component is provided, which is fixedly connected to the mounting sleeve of the micrometer head 4 to ensure that the micrometer head 4 does not wobble when the micrometer thimble or fine-tuning knob is rotated. For example, the micrometer head fixing component includes a fixing block 5, which has a mounting hole for fixing the micrometer head 4. The mounting sleeve of the micrometer head 4 passes through the fixing hole, and the mounting sleeve of the micrometer head 4 is fixedly connected to the fixing block 5. The fixing block 5 is fixedly connected to the first side plate 21 (via a lead screw).

[0029] A spring-loaded screw 6 passes through the second fixing hole. The inner wall of the second fixing hole has an internal thread that matches the external thread of the spring-loaded screw 6. The spring-loaded screw 6 is threadedly connected to the second fixing hole (i.e., the spring-loaded screw 6 is fixed to the second side plate 22). The tip of the spring-loaded screw 6 abuts against the mask plate 100. When adjusting the position of the mask plate 100, it is necessary to ensure that the mask plate 100 can be adjusted in four directions. Figure 3 Moving in the direction indicated by the middle arrow, in this embodiment, by setting spring set screws 6 and pins 3 that abut against the probe of the micrometer head 4 on opposite sides of the mask plate 100, the position adjustment of the mask plate 100 in four directions can be achieved using the micrometer head 4 set on the two adjacent side plates 2. In actual operation, the probe of the micrometer head 4 can be used to push the mask plate 100 away from the micrometer cylinder of the micrometer head 4. During this process, the spring set screws 6 on the opposite side of the micrometer head 4 are further compressed. When the probe of the micrometer head 4 leaves the pin 3, the mask plate 100 pushes the pin 3 to abut against the probe of the micrometer head 4 again under the rebound of the spring set screws 6 on the opposite side. In this way, position adjustment in two directions can be achieved. With a total of two pairs of spring set screws 6 and micrometer heads 4, position adjustment in four directions can be achieved.

[0030] Example 2

[0031] Based on Example 1, this example further optimizes the mask alignment fixture. Preferably, as follows: Figure 1 As shown, the substrate placement area (where the target substrate 200 is located) is situated in the center of the mask accommodating area 11. Within the mask accommodating area 11, substrate leveling blocks 7, with the same height as the target substrate 200, are provided on both sides of the substrate placement area. To reduce light refraction errors, before fine-tuning the position of the mask 100, the top surface of the mask 100 can be directly contacted with the target substrate 200 to improve the alignment accuracy between the target pattern and the target substrate 200, thereby improving the replication accuracy of the target pattern. However, since the target substrate 200 is typically made of thin glass, the thin glass may not be able to withstand the weight of the entire mask 100. Therefore, to alleviate the pressure on the target substrate 200, in this embodiment, substrate leveling blocks 7 with the same height as the target substrate 200 are provided on both sides of the substrate placement area to share the pressure on the mask 100, thereby reducing the risk of the target substrate 200 breaking.

[0032] In this embodiment, the target pattern is aligned with the target substrate 200 by adjusting the position of the mask 100. Since the mask 100 is located within the mask receiving area 11, its movable range is not large. Therefore, it is first necessary to ensure that the target substrate 200 is in the correct position. In this embodiment, the target substrate 200 is restricted by limiting bosses 8 and limiting members. Taking a rectangular substrate placement area as an example, the two adjacent sides of the substrate placement area can be defined by the distribution of multiple limiting bosses 8. Figure 4 As shown, when placing the target substrate 200, firstly, the two adjacent edges of the target substrate 200 abut against the limiting protrusions 8 (all limiting protrusions 8 abut against the target substrate 200). There are at least two limiting protrusions 8, and each of the two limiting protrusions 8 needs to abut against one of the two adjacent edges (two adjacent sidewalls) of the target substrate 200. To prevent the target substrate 200 from moving when adjusting the position of the mask 100 (the top surface of the mask 100 directly abuts against the target substrate 200), limiting members are needed to further limit the target substrate 200. Since limiting protrusions 8 are already provided on both sides of the substrate placement area, to facilitate the placement of the target substrate 200, fixed limiting members should not be placed on the other two sides of the substrate placement area. Therefore, in this embodiment, detachable limiting members are used. After the two sidewalls of the target substrate 200 are tightly abutted against all the limiting protrusions 8, the limiting members abut against the remaining two sidewalls of the target substrate 200. For example, the limiting member includes a magnetic block 10; the fixing base plate 1 is provided with a plurality of magnetic grooves 9 adapted to the magnetic block 10, and the plurality of magnetic grooves 9 are distributed near the other two adjacent sides of the substrate placement area. The structure of the magnetic grooves 9 can be referred to Figure 2 and Figure 5As shown. Specifically, grooves or openings are made near the other two sides of the substrate placement area, and magnets 30 are embedded in the bottom surface of the fixing base plate 1 (opposite to the top surface) at the positions corresponding to the grooves or openings. If it is an opening, the magnets 30 are used as the bottom surface of the magnetic groove 9.

[0033] Furthermore, the mask alignment fixture also includes a protective strip 20. The protective strip 20 has an adapter hole that matches the pin 3 or spring screw 6. The protective strip 20 is arranged around the periphery of the four side plates 2 and is used to cover the pin 3 or spring screw 6 exposed on the side plates 2. Since the pin 3 or spring screw 6 directly abuts against the mask 100, when the position of the mask 100 is fixed, it is necessary to avoid touching the pin 3 or spring screw 6 exposed outside the side plates 2 as much as possible. If accidentally touched, the mask 100 may be displaced. The presence of the protective strip 20 can prevent the above situation from occurring.

[0034] Furthermore, the substrate placement area of ​​the fixed base plate 1 is also reserved with negative pressure adsorption holes 12 for connecting the negative pressure adsorption device. When the mask plate does not abut against the target substrate 200, the target substrate 200 needs to be fixed in the vertical direction (perpendicular to the surface of the fixed base plate 1). The target substrate 200 is usually thin, and the negative pressure adsorption method is unlikely to damage the target substrate 200.

[0035] In this embodiment, the substrate placement area of ​​the fixed base plate is further provided with negative pressure adsorption holes for connecting to the negative pressure adsorption device. It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0036] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A mask alignment fixture, characterized in that, The mask alignment fixture includes: A fixed base is provided with a substrate placement area for placing a target substrate (200) and a mask receiving area (11) for placing a mask (100); the mask (100) is provided with a target pattern to be developed. Adjusting and fixing components are connected to the fixing base and abut against the mask (100); used to adjust the mask (100) to the desired position and fix the mask (100) in the desired position. When the mask (100) is in the desired position, the target pattern is located directly above the substrate placement area.

2. The mask alignment fixture according to claim 1, characterized in that, The fixed base includes: A fixed base plate (1) is provided on the top surface of the fixed base plate (1), and the substrate placement area is located within the mask accommodating area (11). Four side plates (2) are arranged around the fixed base plate (1). The four side plates (2) are fixedly connected to the fixed base plate (1) respectively. The surface of any side plate (2) is perpendicular to the surface of the fixed base plate (1). The side plate (2) is also provided with a connecting and fixing part for connecting the adjustment and fixing assembly.

3. The mask alignment fixture according to claim 2, characterized in that, The substrate placement area is located in the middle of the mask accommodating area (11); within the mask accommodating area (11), substrate height blocks (7) of the same height as the target substrate (200) are respectively provided on both sides of the substrate placement area.

4. The mask alignment fixture according to claim 2, characterized in that, The four side plates (2) include a first side plate (21) with two mutually perpendicular surfaces and a second side plate (22) with two mutually perpendicular surfaces; the connecting and fixing parts include: A through hole and a first fixing hole are provided on the first side plate (21). The axis of the through hole is perpendicular to the axis of the first fixing hole. The fixing hole communicates with the through hole. The axis of the through hole is parallel to the surface of the fixing base plate (1). A second fixing hole is provided on the second side plate (22), and the axial direction of the second fixing hole is parallel to the surface of the fixing base plate (1); The adjusting and fixing component includes: Pin (3), the pin (3) is inserted into the through hole, and one end of it abuts against the mask plate (100); Differential head (4), the end of the measuring rod of the differential head (4) abuts against the end of the pin (3) away from the mask plate (100); the measuring rod and the pin (3) are coaxially arranged; A micrometer head fixing component is fixedly connected to the mounting sleeve of the micrometer head (4); A pin is threadedly connected to the first fixing hole, and one end of the pin can pass through the first fixing hole and abut against the pin (3) that passes through the through hole; A spring set screw (6) is inserted into the second fixing hole. The inner wall of the second fixing hole is provided with an internal thread that matches the external thread of the spring set screw (6). The spring set screw (6) is threadedly connected to the second fixing hole. The tip of the spring set screw (6) abuts against the mask plate (100).

5. The mask alignment fixture according to claim 4, characterized in that, The differential head fixing component includes: The fixing block (5) has a mounting hole for fixing the micro head (4), the mounting sleeve of the micro head (4) passes through the fixing hole, the mounting sleeve of the micro head (4) is fixedly connected to the fixing block (5), and the fixing block (5) is fixedly connected to the first side plate (21).

6. The mask alignment fixture according to claim 4, characterized in that, The mask alignment fixture also includes: The protective strip (20) is provided with an adapter hole that is adapted to the pin (3) or spring set screw (6). The protective strip (20) is arranged around the periphery of the four side plates (2). The protective strip (20) is used to cover the pin (3) or spring set screw (6) exposed on the side plates (2).

7. The mask alignment fixture according to claim 2, characterized in that, The substrate placement area is rectangular, and the fixing base further includes: Multiple limiting bosses (8) are distributed on the top surface of the fixed base plate (1), and the extension lines of the inner sidewalls of the multiple limiting bosses (8) form two adjacent sides of the substrate placement area; the limiting bosses (8) are used to abut against the target substrate (200) and to restrict the target substrate (200) within the substrate placement area. The limiting member is detachably connected to the fixed base plate (1). The limiting member is located near the other two adjacent sides of the substrate placement area and is used to cooperate with the limiting boss (8) to fix the position of the target substrate (200).

8. The mask alignment fixture according to claim 7, characterized in that, The limiting component includes a magnetic block (10); the fixed base plate (1) is provided with a plurality of magnetic grooves (9) adapted to the magnetic block (10), and the plurality of magnetic grooves (9) are distributed near the other two adjacent sides of the substrate placement area.

9. The mask alignment fixture according to any one of claims 2 to 8, characterized in that, The base plate (1) of the fixed base plate (1) also has a negative pressure adsorption hole (12) reserved in the substrate placement area for connecting the negative pressure adsorption device.

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