A design device for glue coating, developing and baking unit upper cover temperature control and process exhaust

Abstract

This invention provides a design device for temperature control and process exhaust ventilation of the upper cover of a photoresist coating, developing, and baking unit. The exhaust sealing cover, sealing ring, upper cover, heating element, lower cover, and perforated plate are arranged sequentially from top to bottom. The exhaust sealing cover is fixedly connected to the upper cover. The upper cover and lower cover are fixedly connected to form a cavity. The heating element is installed in the cavity and is in close contact with the lower surface of the upper cover and the upper surface of the lower cover. The lower surface of the lower cover is a frustum. The perforated plate is fixedly connected to the lower cover, and several through holes are distributed on the surface of the perforated plate. The through holes are distributed outwards circumferentially along the radius of the perforated plate, and their diameter gradually increases. The exhaust pipe is connected to the exhaust sealing cover, and the airflow regulating device is installed at the tail of the exhaust pipe. This invention not only improves the uniformity and stability of airflow but also solves the problem of uneven heating of photoresist in the thick photoresist coating process, demonstrating significant advantages.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor manufacturing technology, specifically, it relates to a design device for temperature control and process exhaust of the upper cover of a coating, developing and baking unit. Background Technology

[0002] In semiconductor manufacturing, the photoresist coating, developing, and baking unit is a critical piece of equipment. It is primarily used to coat the silicon wafer surface with photoresist, then pattern the photoresist through exposure and development, and finally bake to cure it. Because photoresist is volatile, volatiles are generated during baking. To prevent these volatiles from affecting the coating effect on the wafer surface, they must be removed. The uniformity of the exhaust airflow during volatile removal significantly impacts the photoresist coating effect. Uneven airflow can lead to uneven photoresist thickness, affecting the quality of subsequent processes. Furthermore, different process requirements dictate varying photoresist thickness requirements. In processes requiring thicker coatings, baking only one side of the wafer can result in uneven heating of the photoresist; the lower layer near the hot plate may have already cured, while the upper layer remains fluid, also affecting the quality of subsequent processes.

[0003] In existing technologies, airflow control in photoresist coating, developing, and baking units is primarily achieved by adjusting wind speed and volume. However, this method often fails to guarantee absolute airflow uniformity, especially in large photoresist coating, developing, and baking units, where this problem becomes more pronounced. Firstly, due to the large size of the equipment, ensuring airflow uniformity is difficult, leading to uneven photoresist coating and affecting product quality. Secondly, existing photoresist coating, developing, and baking units do not consider airflow stability; during exhaust, airflow may form, potentially causing unstable photoresist coating and affecting product consistency.

[0004] Existing technologies do not address how to achieve uniform heating of the photoresist in processes that require thick photoresist coating on wafers.

[0005] Chinese Patent No. CN209992805U discloses a hot plate cavity cover. The exhaust airflow uniformity in the baking chamber of the baking equipment using this hot plate cavity cover is poor and the airflow is unstable, which can easily affect the uniformity of the photoresist thickness on the wafer surface. At the same time, the influence of uneven heating of the photoresist in the thick coating process is not considered. Utility Model Content

[0006] The purpose of this utility model is to provide a design device for temperature control and process exhaust of the upper cover of a photoresist coating, developing, and baking unit. Compared with the prior art, this technical solution mainly solves the following problems: 1. The technical problem that it is difficult to ensure the uniformity of airflow in the existing photoresist coating, developing, and baking unit; 2. The technical problem that the existing photoresist coating, developing, and baking unit does not take into account the stability of airflow, which may lead to unstable photoresist coating effect and thus affect the consistency of the product; 3. The technical problem that the existing photoresist coating, developing, and baking unit does not consider the impact of uneven heating of photoresist on subsequent quality in the thick coating process.

[0007] To solve the above problems, the technical solution adopted by this utility model is as follows: A design device for temperature control and process exhaust ventilation of the upper cover of a coating, developing, and baking unit, comprising a wafer placed on a hot plate, and further comprising: an exhaust sealing cover, a sealing ring, an upper cover, a heating element, a lower cover, a perforated plate, an exhaust pipe, and an airflow regulating device; the exhaust sealing cover, sealing ring, upper cover, heating element, lower cover, and perforated plate are arranged in order from top to bottom, and the wafer is located between the perforated plate and the hot plate; the bottom of the exhaust sealing cover is provided with a sealing groove, and the sealing ring is embedded in the sealing groove. Inside, the exhaust sealing cover is fixedly connected to the upper cover; the upper cover is fixedly connected to the lower cover and forms a cavity, the heating element is installed in the cavity and is in close contact with the lower surface of the upper cover and the upper surface of the lower cover; the lower surface of the lower cover is a frustum, the perforated plate is fixedly connected to the lower cover, and the surface of the perforated plate is distributed with several through holes, which are distributed outward circumferentially along the radius of the perforated plate and gradually increase in diameter; the exhaust pipe is connected to the exhaust sealing cover, and the air volume regulating device is installed at the tail of the exhaust pipe.

[0008] Furthermore, the heating element is a mica heating element with an integrated temperature sensor.

[0009] Furthermore, the through holes of the porous plate are divided into 3-5 rings at equal intervals along the radial direction.

[0010] Furthermore, the base angle θ of the axial section of the frustum surface of the lower cover is 10-30°.

[0011] Furthermore, it also includes an exhaust support and a connector. The exhaust support is fixedly connected to the top cover by screws. One end of the exhaust support is connected to one end of the exhaust pipe. The connector is installed inside the exhaust support and communicates with the exhaust sealing cover through the exhaust pipe.

[0012] Furthermore, the exhaust support is provided with knob plungers on both sides, and the plunger head of the knob plunger extends into the positioning hole of the connector.

[0013] Furthermore, it also includes an exhaust flange, which is fixedly connected to the connector by screws, and the air volume regulating device is installed on the side of the exhaust flange.

[0014] Furthermore, the exhaust sealing cover is fixedly connected to the upper cover, the upper cover to the lower cover, and the perforated plate to the lower cover by screws.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] 1. The hot plate of this utility model conducts heat through the back of the wafer, so that the photoresist under layer can be cured quickly; the temperature of the heating plate is precisely controlled, and the heating plate radiates heat to the upper layer of photoresist through the lower cover and the frustum surface, heating from top to bottom at the same time, so that the temperature of the photoresist surface is uniform, thus solving the problem of uneven heating of photoresist in the thick coating process.

[0017] 2. The lower surface of the bottom cover is a frustum. During exhaust, the gas enters the exhaust chamber along the frustum. The frustum guides the hot air flow field to diffuse radially, increasing the stability of the airflow during exhaust. This avoids the problem of unstable photoresist coating caused by unstable airflow, thus improving product reliability. Combined with the through-holes with gradually changing apertures, this makes the airflow of varying speeds uniform, preventing some areas from having fast airflow and others from having slow airflow. This improves the uniformity of the exhaust airflow, ensuring uniform photoresist coating and improving product quality.

[0018] 3. The sealing structure features a sealing ring embedded in the sealing groove to prevent external air from seeping in and avoid airflow disturbance; combined with an airflow regulating device, it can precisely control the discharge of process waste gas and prevent volatile organic compounds from overflowing and polluting the environment.

[0019] 4. The knob plunger is adapted to the rapid maintenance needs of semiconductor equipment. The plunger head and positioning hole cooperate to ensure the coaxiality and positional accuracy of the exhaust support and connecting parts, and avoid assembly deviations from affecting the sealing of the exhaust path. In the locked state, it provides reliable mechanical positioning to prevent the equipment from loosening in high temperature or vibration environments, and meets the stringent stability requirements of semiconductor equipment. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0021] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0022] Figure 3 This is a schematic diagram of the installation cross-sectional structure of the connector of this utility model;

[0023] Figure 4 This is a schematic diagram of the perforated plate structure of this utility model;

[0024] In the diagram: 1. Exhaust sealing cover; 101. Sealing groove; 2. Sealing ring; 3. Top cover; 301. Cavity; 4. Heating element; 5. Bottom cover; 501. Frustum; 6. Perforated plate; 601. Through hole; 7. Exhaust support; 8. Exhaust pipe; 9. Connector; 901. Positioning hole; 10. Exhaust flange; 11. Knob plunger; 1101. Plunger head; 12. Air volume adjustment device. Detailed Implementation

[0025] To more clearly illustrate the overall concept of this utility model, a detailed description will be provided below with reference to the accompanying drawings.

[0026] It should be noted that many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0027] Furthermore, it should be understood in the description of this utility model that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" 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 this utility model 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 this utility model.

[0028] The present invention will be further described below with reference to specific embodiments.

[0029] This utility model provides a design device for temperature control and process exhaust ventilation of the upper cover of a coating, developing, and baking unit. It includes a wafer placed on a hot plate, and further comprises: an exhaust sealing cover 1, a sealing ring 2, an upper cover 3, a heating element 4, a lower cover 5, a perforated plate 6, an exhaust pipe 8, and an airflow regulating device 12. The exhaust sealing cover 1, sealing ring 2, upper cover 3, heating element 4, lower cover 5, and perforated plate 6 are arranged sequentially from top to bottom, with the wafer located between the perforated plate and the hot plate. The bottom of the exhaust sealing cover 1 has a sealing groove 101, and the sealing ring 2 is embedded in the sealing groove 101. The exhaust sealing cover 1 and the... The upper cover 3 is fixedly connected; the upper cover 3 and the lower cover 5 are fixedly connected to form a cavity 301, the heating element 4 is installed in the cavity 301 and is in close contact with the lower surface of the upper cover 3 and the upper surface of the lower cover 5; the lower surface of the lower cover 5 is a frustum 501, the perforated plate 6 is fixedly connected to the lower cover 5, and a plurality of through holes 601 are distributed on the surface of the perforated plate 6. The through holes 601 are distributed outward circumferentially along the radial direction of the perforated plate 6 and the diameter gradually increases; the exhaust pipe 8 is connected to the exhaust sealing cover 1, and the air volume regulating device 12 is installed at the tail of the exhaust pipe 8.

[0030] During use, the heating element 4 is installed in the cavity 301 formed by the upper cover 3 and the lower cover 5, and transfers heat downward to the frustum 501 of the lower cover 5 through thermal radiation. The frustum 501 radiates heat evenly to the upper layer of photoresist on the wafer surface, forming a "two-way temperature control" with the conduction heating of the lower hot plate: the lower layer heating is achieved by the hot plate conducting heat through the back of the wafer, which quickly cures the bottom layer of photoresist; the upper layer heating is achieved by the heating element 4 radiating heat to the upper layer of photoresist through the frustum 501, avoiding the temperature gradient problem of the upper layer not being cured and the lower layer being cross-linked in the thick adhesive process, and achieving a small temperature difference between the upper and lower layers; the sealing ring 2 embedded in the sealing groove 101 prevents external air from seeping in and avoids airflow disturbance; the air volume adjustment device 12 adjusts the opening degree through the PLC system to adjust the exhaust air volume, and drives the blades or baffles to rotate through the electric actuator to change the ventilation cross-sectional area, realizing stepless adjustment of the exhaust volume, adapting to the solvent evaporation requirements of different types of photoresist, ensuring that the volatile gas is just drawn away and will not leave residues that affect chip quality.

[0031] Preferably, the heating element 4 is a mica heating element with an integrated temperature sensor; the sensor integrated in the heating element 4 monitors the temperature in real time, and works with an external PID temperature control module to control the temperature accuracy, ensuring heating stability under different adhesive thickness processes;

[0032] Preferably, the through holes 601 of the perforated plate 6 are divided into 3-5 rings at equal intervals along the radial direction; the through holes 601 of the perforated plate 6 gradually increase in diameter from the inner ring to the outer ring along the radial direction to compensate for the high flow velocity at the center of the airflow and the low flow velocity at the outer periphery. This makes the airflow with different speeds uniform, so that there are no places where the airflow is fast and other places where the airflow is slow.

[0033] Preferably, the base angle θ of the axial section of the frustum surface 501 of the lower cover 5 is 10-30°; when the solvent vapor volatilized from the wafer surface flows upward, the frustum surface 501 of the lower cover 5 will converge the divergent airflow into axial flow, reducing the formation of turbulence.

[0034] Preferably, the device also includes an exhaust support 7 and a connector 9. The exhaust support 7 is fixedly connected to the upper cover 3 by screws. One end of the exhaust support 7 is connected to one end of the exhaust pipe 8. The connector 9 is installed inside the exhaust support 7 and communicates with the exhaust sealing cover 1 through the exhaust pipe 8. The exhaust support 7 has knob plungers 11 on both sides. The plunger head 1101 of the knob plunger 11 extends into the positioning hole 901 of the connector 9. The knob plunger 11 is adapted to the rapid maintenance requirements of semiconductor equipment. The plunger head 1101 cooperates with the positioning hole 901 to ensure the coaxiality and positional accuracy of the exhaust support 7 and the connector 9, and avoids assembly deviations from affecting the sealing of the exhaust path. In its locked state, it provides reliable mechanical positioning to prevent the equipment from loosening in high temperature or vibration environments, and meets the stringent stability requirements of semiconductor equipment.

[0035] Preferably, it also includes an exhaust flange 10, which is fixedly connected to the connector 9 by screws. The air volume regulating device 12 is installed on the side of the exhaust flange 10. The independent flange structure can be disassembled separately, which facilitates the maintenance of the air volume regulating device 12 or the connector 9 without disassembling the overall exhaust path. The air volume regulating device 12 adjusts the opening degree through a PLC system to regulate the exhaust air volume. It drives the blades or baffles to rotate through an electric actuator, changing the ventilation cross-sectional area to achieve stepless adjustment of the exhaust air volume. This adapts to the solvent evaporation requirements of different photoresist types, ensuring that the evaporating gas is just drawn away and does not leave residues that affect chip quality. The internal structure of the air volume regulating device 12 is all existing technology, and its internal structure is not an innovation of this utility model, so it will not be explained in detail here.

[0036] Preferably, the exhaust sealing cover 1 is fixedly connected to the upper cover 3, the upper cover 3 is fixedly connected to the lower cover 5, and the perforated plate 6 is fixedly connected to the lower cover 5 by screws.

[0037] The working principle of this utility model is as follows:

[0038] The upper cover 3 and the lower cover 5 of this utility model form a sealed cavity 301, with a built-in heating element 4 and an integrated temperature sensor. Heat conduction is achieved through close contact between the upper and lower cover surfaces. When the heating element 4 is powered on, it generates heat, which is transferred through the lower cover 5 to the frustum surface 501 on its lower surface, and then evenly radiated to the wafer surface through the perforated plate 6, thereby achieving precise temperature control of the wafer. The temperature sensor monitors the temperature of the heating element 4 in real time and adjusts the heating power through closed-loop control to ensure that the temperature fluctuation of the wafer surface meets the requirements of the semiconductor photoresist baking process.

[0039] The frustum surface 501 of the lower cover 5 gathers the rising hot airflow generated by the heating element 4 and guides it to the perforated plate 6, avoiding energy loss caused by heat diffusion to the surroundings. The slope of the frustum surface creates a velocity gradient with a high center and low outer periphery during the upward flow of the airflow. Combined with the diameter gradient of the through holes 601 of the perforated plate 6, which has a small center diameter and a large outer periphery diameter, the resistance of the outer periphery path can be offset, ultimately achieving a uniform distribution of airflow velocity on the wafer surface and avoiding the influence of local eddies on the solvent evaporation rate of the wafer surface.

[0040] After volatilization, the process waste gas enters the exhaust sealing cover 1 through the perforated plate 6, and passes through the exhaust pipe 8, connector 9, and exhaust flange 10. Finally, the flow rate is controlled by the air volume regulating device 12 at the tail. The air volume regulating device 12 changes the ventilation cross-sectional area by rotating blades. Combined with the temperature and pressure signals received by the external control system, it adjusts the exhaust volume in real time to ensure that the waste gas is discharged in time while maintaining a slightly negative pressure environment in the cavity to prevent external pollutants from entering.

[0041] The exhaust sealing cover 1 forms a seal with the upper cover 3 through the sealing ring 2. The plunger head 1101 of the knob plunger 11 is inserted into the positioning hole 901 of the connector 9 to ensure that there is no leakage in the exhaust path. The exhaust support 7 and the exhaust flange 10 realize the rigid connection between the exhaust pipe 8 and the external waste gas treatment system, adapt to the factory's standardized pipe interface, and improve the equipment installation compatibility.

[0042] By coordinating temperature control and exhaust ventilation, the device can improve heating uniformity and exhaust efficiency in the coating and developing process.

[0043] In summary, compared with the prior art, this invention not only improves the uniformity and stability of airflow and achieves precise airflow control, but also improves the quality and consistency of products. At the same time, it solves the problem of uneven heating of photoresist in the thick photoresist application process, and has significant advantages.

[0044] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A design device for temperature control and process ventilation of the top cover of a coating, developing, and baking unit, comprising a wafer placed on a hot plate, characterized in that, Also includes: Exhaust sealing cover (1), sealing ring (2), upper cover (3), heating element (4), lower cover (5), perforated plate (6), exhaust pipe (8) and air volume regulating device (12); The exhaust sealing cover (1), sealing ring (2), upper cover (3), heating plate (4), lower cover (5), and perforated plate (6) are arranged in order from top to bottom, and the wafer is located between the perforated plate and the heating plate; the exhaust sealing cover (1) has a sealing groove (101) at the bottom, the sealing ring (2) is embedded in the sealing groove (101), and the exhaust sealing cover (1) is fixedly connected to the upper cover (3); The upper cover (3) is fixedly connected to the lower cover (5) to form a cavity (301). The heating element (4) is installed in the cavity (301) and is in close contact with the lower surface of the upper cover (3) and the upper surface of the lower cover (5). The lower surface of the lower cover (5) is a frustum (501). The perforated plate (6) is fixedly connected to the lower cover (5). A plurality of through holes (601) are distributed on the surface of the perforated plate (6). The through holes (601) are distributed outward circumferentially along the radial direction of the perforated plate (6) and their diameter gradually increases. The exhaust pipe (8) is connected to the exhaust sealing cover (1), and the air volume regulating device (12) is installed at the tail of the exhaust pipe (8).

2. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 1, characterized in that, The heating element (4) is a mica heating element with an integrated temperature sensor.

3. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 2, characterized in that, The through holes (601) of the perforated plate (6) are divided into 3-5 rings at equal intervals along the radial direction.

4. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 3, characterized in that, The base angle θ of the axial section of the frustum surface (501) of the lower cover (5) is 10-30°.

5. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 1, characterized in that, It also includes an exhaust support (7) and a connector (9). The exhaust support (7) is fixedly connected to the top cover (3) by screws. One end of the exhaust support (7) is connected to one end of the exhaust pipe (8). The connector (9) is installed inside the exhaust support (7) and communicates with the exhaust sealing cover (1) through the exhaust pipe (8).

6. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 5, characterized in that, The exhaust support (7) is provided with knob plungers (11) on both sides, and the plunger head (1101) of the knob plunger (11) extends into the positioning hole (901) of the connector (9).

7. The design device for temperature control and process exhaust of the upper cover of the coating, developing, and baking unit according to claim 1, characterized in that, It also includes an exhaust flange (10), which is fixedly connected to the connector (9) by screws, and the air volume regulating device (12) is installed on the side of the exhaust flange (10).

8. The design device for temperature control and process exhaust of the upper cover of the coating, developing and baking unit according to claim 1, wherein the exhaust sealing cover (1) and the upper cover (3), the upper cover (3) and the lower cover (5), and the perforated plate (6) and the lower cover (5) are all fixedly connected by screws.

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