A cold trap device for preventing photoresist from condensing on an activation furnace butterfly valve

Abstract

The utility model discloses a kind of cold trap devices for preventing photoresist from condensing on activation furnace butterfly valve, the utility model relates to IC manufacturing semiconductor manufacturing technical field, especially the high-temperature activation tool of semiconductor manufacturing, including cylindrical shell, cylindrical shell its lateral wall is provided with airflow inlet, top end portion is provided with airflow outlet;Condensing plate, it is set in the chamber of the cylindrical shell, including airflow inlet, airflow outlet and multistage condensing plate, wherein, the multistage condensing plate is sequentially arranged from the airflow inlet to the airflow outlet, and have gradually reduced temperature according to predetermined temperature gradient, so that the airflow flowing through is fractionally condensed;The utility model is installed cold trap in the specific position of high-temperature pipeline, and the directional capture of volatile matter is realized by gradient temperature control and multistage condensing structure, volatile matter sequentially passes through multistage condensing plate, realizes fractional collection, prolongs PM cycle, reduces maintenance frequency and comprehensive cost.

Description

Technical Field

[0001] This utility model relates to the field of IC manufacturing and semiconductor manufacturing technology, and in particular to a high-temperature activation tool for semiconductor manufacturing, specifically a cold trap device to prevent photoresist from condensing on the butterfly valve of the activation furnace. Background Technology

[0002] In the high-temperature activation process of semiconductor manufacturing, photoresist releases volatile organic compounds, such as solvents and resin monomers, after being heated. When these volatiles migrate with the airflow in the high-temperature pipeline to the lower-temperature butterfly valve area, they condense due to the temperature difference, causing scale buildup, jamming, or even failure on the butterfly valve surface, seriously affecting process stability and equipment lifespan.

[0003] In the TEOS process of semiconductor manufacturing, tetraethoxysilane condenses and crystallizes on the pump line after heating. These crystals can fall into the pump, causing it to jam and shut down, leading to backflow of gas. Cold traps are installed on the pump line to ensure that volatiles condense due to the temperature difference as they migrate with the gas flow to a cooler region, accumulating the reactants in the cold trap and preventing them from falling into the pump. However, temperature control presents a dilemma: while increasing the butterfly valve temperature can reduce condensation, it may trigger photoresist pre-curing or thermal decomposition, affecting the performance of subsequent processes. Low adsorption efficiency: passive adsorption devices cannot directionally capture volatiles and are prone to condensation at the butterfly valve, requiring frequent PM (particulate matter) operations, increasing operating costs.

[0004] Traditional solutions, such as increasing the butterfly valve temperature or improving the valve coating, have significant drawbacks. Temperature control is contradictory: simply increasing the butterfly valve temperature may compromise the thermal stability of the photoresist, causing pre-curing problems. Coating durability is insufficient: anti-stick coatings are prone to failure under high-temperature chemical corrosion, requiring frequent maintenance. Passive protection is ineffective: current technologies cannot actively capture volatiles, only delaying rather than eliminating the condensation problem. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a device to prevent photoresist from condensing on the butterfly valve of the activation furnace. This invention involves installing a cold trap at a specific location in the high-temperature pipeline to actively regulate the local temperature field, preferentially condensing and collecting photoresist volatiles in a controllable area, thus preventing their migration to the butterfly valve.

[0006] To achieve the above objectives, the first technical solution adopted by this utility model is: a cold trap device for preventing photoresist from condensing on the butterfly valve of an activation furnace, comprising: a cylindrical shell, wherein an airflow inlet is provided on the side wall of the cylindrical shell and an airflow outlet is provided at the top end; a condensing plate, which is disposed in the cavity of the cylindrical shell and includes an airflow inlet, an airflow outlet and a multi-stage condensing plate, wherein the multi-stage condensing plate is arranged sequentially from the airflow inlet to the airflow outlet and has a temperature that gradually decreases according to a predetermined temperature gradient, so that the flowing airflow is condensed in stages.

[0007] Optionally, the cold trap device can be connected to the bend in the airflow pipeline upstream of the butterfly valve through the airflow inlet and airflow outlet of the cylindrical outer shell.

[0008] Optionally, the relative positions of the multi-stage condenser plates are arranged in a spiral or staggered manner.

[0009] Optionally, the inner wall of the cylindrical shell includes a multi-layer heat exchange structure, so that the inner wall of the cylindrical shell and the high-temperature zone of the airflow pipeline upstream of the butterfly valve form a temperature difference of 50~100°C.

[0010] Optionally, it further includes: a flow divider disposed in the cavity of the cylindrical outer shell near the airflow inlet to directionally divide the airflow flowing into the airflow inlet.

[0011] Alternatively, the pipe heating is cooled by a multi-stage condenser plate.

[0012] Optionally, the cold trap device is integrated into the internal cavity of the butterfly valve.

[0013] Optionally, it also includes a ceramic fiber insulation layer, which is attached to the outer wall of the cylindrical outer shell.

[0014] Optionally, it also includes a hydrophobic nanocoating applied to the inner wall of the cylindrical shell.

[0015] The beneficial effects of this utility model are: This invention utilizes a cold trap installed at a specific location in a high-temperature pipeline to achieve directional capture of volatiles through gradient temperature control and a multi-stage condensation structure. It actively regulates the local temperature field, preferentially condensing and collecting photoresist volatiles within a controllable area, preventing their migration to the butterfly valve. This scheme combines fluid dynamics and temperature control design to achieve active enrichment and efficient condensation of volatiles, avoiding the randomness of passive adsorption. The TiO2-based hydrophobic coating prepared using the sol-gel method possesses both anti-adhesion and photocatalytic degradation functions for residues, extending maintenance cycles.

[0016] This system eliminates the risk of condensation on the butterfly valve surface, improving valve reliability. High-temperature airflow carries photoresist volatiles into the cold trap area. Due to the vortex generated by the bent structure, the volatiles accumulate on the inner wall of the cold trap. The volatiles then pass through multiple stages of condensation plates. High-boiling-point components condense in the high-temperature section, while low-boiling-point components are captured in the low-temperature section, achieving graded collection, reducing process contamination, and ensuring wafer yield. It also extends the PM cycle and reduces maintenance frequency and overall costs. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the external structure of the device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to this utility model. Figure 2 This is a schematic diagram of the internal structure of the device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to this utility model; Figure 3 This is a schematic diagram of the temperature control unit structure of the device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to this utility model. Figure 4 This is a schematic diagram of the single-piece condenser plate structure of the device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to this utility model.

[0018] Reference numerals: 1. Cylindrical outer shell; 2. Airflow inlet; 3. Airflow outlet; 4. Condenser plate; 5. Diverter plate; 6. Conical ring; 7. Pressure ring; 8. Tray; 9. Positioning shaft; 10. Guide shaft; 11. Bottom end cover; 12. Temperature control unit; 13. Intelligent temperature control module; 14. Gradient temperature control cold trap module; 15. Electric cooler; 16. Temperature sensor. Detailed Implementation

[0019] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0020] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover 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..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0021] This invention provides a cold trap device for preventing photoresist from condensing on the butterfly valve of an activation furnace. The device includes a cylindrical outer shell 1, which has a cylindrical cavity structure to facilitate gas condensation and easy connection to pipes. The cylindrical outer shell 1 employs a thermal insulation structure to create a closed, thermally insulated space inside, facilitating temperature regulation. An airflow inlet 2 is provided on the side wall of the cylindrical outer shell 1, through which gas enters the cold trap during use. An airflow outlet 3 is provided at the top, through which the treated gas flows out. The inner surface of the cylindrical outer shell 1 is covered with a hydrophobic nano-coating, which combines anti-adhesion and photocatalytic degradation of residues, extending the maintenance cycle. The hydrophobic nano-coating is based on biomimetic nanoscale functional materials, specifically ultrahydrophobic nanomaterials inspired by the self-cleaning effect of lotus leaf surfaces. It achieves waterproof, anti-fouling, and self-cleaning functions through the construction of microscopic nanostructures.

[0022] In one specific embodiment of this application, the cold trap further includes a condenser plate 4, disposed within the chamber of the cylindrical outer shell 1, connecting the airflow inlet 2 and the airflow outlet 3. After the gas enters the cold trap, it is cooled by the condenser plate 4 and then discharged from the cold trap. The condenser plate 4 adopts a multi-stage condenser plate structure; specifically, a single condenser plate is as follows: Figure 4 As shown, the gas entering the cold trap is cooled by multi-stage condensation, which greatly improves the condensation effect.

[0023] In one specific embodiment of this application, the cold trap also includes a temperature control unit 12, which can control the temperature inside the cold trap. Multiple temperature zones are set inside the cold trap so that the temperature of each condenser plate decreases step by step. Volatile substances pass through multiple condenser plates in sequence. High-boiling-point components are condensed in the high-temperature section, and low-boiling-point components are captured in the low-temperature section, realizing graded collection, directional capture of volatile substances, reducing process contamination, and ensuring wafer yield.

[0024] In one specific embodiment of this application, staggered condenser plates 4 are provided to increase the capture efficiency by increasing the contact area. The temperature of each condenser plate decreases progressively, optionally from 150°C to 50°C, to achieve staged condensation of photoresist volatiles and preferentially capture high / low boiling point components. The cold trap uses staggered condenser plates to increase the capture efficiency by increasing the contact area and extending the residence time of volatiles.

[0025] In one specific embodiment of this application, the inner wall of the cold trap is covered with a TiO2-based nanocomposite hydrophobic coating, which has both anti-adhesion and photocatalytic degradation functions, reducing condensate residue. The TiO2-based nanocomposite hydrophobic coating achieves zero condensate residue through nanoscale roughening and low surface energy chemical modification, extending the maintenance cycle by 6 times and reducing maintenance costs by 75%, thus driving the upgrade towards maintenance-free operation. The coating surface is formed into a hierarchical structure of papillae and nanofibers through a nano-powdering process. This hierarchical structure can be a TiO2 nanorod array with a roughness parameter Ra of 1-5 μm, allowing air to form an "air cushion layer" in the depressions. When condensate particles, generally larger than 1 μm, come into contact with the coating, the actual contact area is only 1%-5% of the apparent area, resulting in significantly reduced adhesion, and they can be detached by vibration. Due to the surface energy difference, the condensate particles cannot be adsorbed by the coating and pass directly through with the inertia of the airflow or are carried away by subsequent airflow.

[0026] In one specific embodiment of this application, a graphene-based superhydrophobic coating is used to enhance high-temperature resistance. This graphene-based superhydrophobic coating mimics the superhydrophobic properties of lotus leaves by embedding nanoscale modified graphene into an elastomer. The novel coating is prepared by partially embedding modified graphene into the elastomer, and this superhydrophobic sample has the potential for use in high-temperature environments. The graphene-based superhydrophobic coating exhibits excellent chemical / mechanical durability and heat resistance, and can be strongly bonded to ceramics, metals, organic materials, etc., and is easy to mass-produce. This environmentally friendly and low-cost novel graphene superhydrophobic coating has demonstrated significant competitive advantages in applications such as self-cleaning, corrosion prevention, anti-fogging, and anti-icing.

[0027] In one specific embodiment of this application, the airflow inlet 2 and airflow outlet 3 on the cylindrical outer shell 1 are respectively connected to the pipeline at the bend upstream of the butterfly valve, so that the cold trap is set on the pipeline at the bend upstream of the butterfly valve, and the volatiles are concentrated in the cold trap area by using fluid inertia. The temperature difference between the cold trap and the butterfly valve is controlled, and the temperature difference here is ≥50°C to ensure that the volatiles are completely intercepted before reaching the butterfly valve.

[0028] In one specific embodiment of this application, the cold trap can be integrated inside the butterfly valve, and the condensation function can be achieved through the hollow structure design of the valve, thereby improving the condensation effect.

[0029] In one specific embodiment of this application, the multi-stage condenser plates in the condenser plate 4 are configured with a spiral or staggered structure. The condenser plates are made of a high thermal conductivity material, specifically a copper-aluminum alloy. This increases the contact area and prolongs the residence time of volatiles, thereby improving capture efficiency. The copper-aluminum alloy is a composite of copper and aluminum. Copper has excellent thermal conductivity, while aluminum has good heat dissipation and lightweight properties. This combination achieves an optimal balance between thermal conductivity and heat dissipation in the condenser plate 4. Simultaneously, aluminum has good oxidation resistance, forming a dense oxide film in the air to prevent further oxidation. While copper is relatively corrosion-resistant, it is susceptible to oxidation under certain conditions, forming verdigris. The copper-aluminum alloy, with its superior oxidation resistance, significantly extends the service life of the condenser plate 4.

[0030] In one specific embodiment of this application, the condensation structure employs a spiral guide plate, utilizing centrifugal force to concentrate volatiles towards the inner wall of the cold trap. However, the guide angle needs to be optimized to avoid pressure loss. A spiral guide plate, also known as a spiral racetrack, is a device that increases fluid friction and turbulence within a pipe by reducing the fluid cross-sectional area and distorting the streamlines. Installed inside a heat transfer jacket, it increases the heat transfer coefficient by altering the fluid's flow path and velocity distribution, thereby improving heat transfer efficiency. Adding a spiral guide plate inside the heat transfer jacket increases the heat transfer area, making the heat exchange effect more significant. The spiral guide plate induces fluid turbulence, generating greater frictional resistance. This resistance disrupts the molecular motion within the fluid, further increasing the heat transfer coefficient and improving the heat transfer effect. During its operation, the spiral guide plate reduces localized fouling within the pipe, hinders fluid turbulence, reduces frictional resistance, and decreases energy consumption.

[0031] In one specific embodiment of this application, the temperature control unit 12 includes a gradient temperature control cold trap module 14 and an intelligent temperature control module 13. The intelligent temperature control module 13 includes a thermoelectric cooler 15 and a temperature sensor 16. The temperature sensor 16 is disposed in multiple gradient regions inside the condenser plate, forming a closed-loop temperature control and feedback system. The cold trap temperature is adjusted in real time to ensure stable condensation efficiency, and the cold trap temperature is dynamically adjusted according to the airflow rate and volatile concentration.

[0032] In one specific embodiment of this application, the cooling method uses liquid nitrogen circulation cooling, which directly reduces the temperature of the cold trap through a cryogenic fluid. Liquid nitrogen circulation cooling can achieve extremely low temperatures and rapid response.

[0033] In one specific embodiment of this application, a ceramic fiber insulation layer is provided between the cold trap and the high-temperature pipeline to reduce heat conduction interference. Ceramic fibers have a very low thermal conductivity, typically between 0.08 and 0.15 W / m•K from room temperature to 1000°C, far lower than that of refractory bricks, metals, and glass. Heat is difficult to penetrate ceramic fibers quickly through conduction. Their highly porous microstructure—with a porosity exceeding 80%—acts as a barrier, blocking heat transfer channels, especially since air is a poor conductor of heat. The disordered fiber arrangement also inhibits heat convection: the random, interwoven three-dimensional structure of ceramic fibers prevents effective convection channels for hot air, effectively suppressing heat transfer. Furthermore, their strong infrared reflectivity helps suppress radiative heat. Ceramic fibers possess excellent infrared reflectivity, which can mitigate the intrusion of high-temperature radiative heat, making them particularly important in high-temperature furnaces and infrared heating equipment. Finally, their low heat capacity allows for rapid heating while maintaining strong heat retention. The low density and small specific heat capacity of ceramic fibers make them less prone to heat absorption, resulting in high heating efficiency, long heat retention time, and significant energy-saving advantages, reducing energy consumption by 30-60%.

[0034] In one specific embodiment of this application, the inner wall of the cold trap adopts a multi-layer heat exchange structure. This heat exchange structure can be a serpentine cooling pipe, forming a temperature difference of 50~100°C with the high-temperature zone of the pipe, ensuring preferential condensation of volatiles. The condensation cavity is made of a high thermal conductivity material, which is made of copper-aluminum alloy and covered with a hydrophobic nano-coating to reduce condensate residue.

[0035] In one specific embodiment of this application, a flow divider 5 is also provided inside the cold trap. The flow divider 5 is located at the airflow inlet. After the gas enters the cold trap, the flow divider 5 divides the gas into multiple paths that flow into the condenser plate 4, thereby improving the heat dissipation effect. At the same time, it can also enable the gas to be captured in a directional manner after entering the cold trap.

[0036] In one specific embodiment of this application, the multi-stage condenser plate is configured as a cylinder, and the outer diameter is not greater than the inner diameter of the cylindrical shell 1, so that the condenser plate 4 can fill the cylindrical shell 1, ensuring that the gas entering the cold trap can be cooled by passing through the condenser plate 4, thereby improving the condensation effect.

[0037] In one specific embodiment of this application, the condenser plate 4 further includes an annular condenser plate disposed at the end. The annular condenser plate can make the gas passing through the condenser plate cool more completely and improve the condensation effect.

[0038] In one specific embodiment of this application, a positioning shaft 9 and a guide shaft 10 are also provided inside the cylindrical outer shell 1. The positioning shaft 9 and the guide shaft 10 are arranged along the axial direction of the cold trap and pass through the condenser plate 4, which facilitates the installation and stability of the condenser plate cylinder.

[0039] In one specific embodiment of this application, the cylindrical outer shell 1 is further provided with a conical ring 6, a pressure ring 7, a tray 8 and a bottom end cap 11, which can improve the condensation effect of the condensing plate 4 and form a sealed space inside the cold trap, which facilitates the implementation of gradient temperature control.

[0040] In one specific embodiment of this application, the workflow includes: First, volatile enrichment: High-temperature gas flow carries photoresist volatiles into the cold trap region. Due to the vortex generated by the bent structure, the volatiles accumulate towards the inner wall of the cold trap. Second, gradient condensation: The volatiles pass through multiple stages of condensation plates in sequence. High-boiling-point components condense in the high-temperature section, while low-boiling-point components are captured in the low-temperature section, achieving graded collection.

[0041] This invention utilizes a cold trap installed at a specific location in a high-temperature pipeline to achieve directional capture of volatiles through gradient temperature control and a multi-stage condensation structure. It actively regulates the local temperature field, preferentially condensing and collecting photoresist volatiles within a controllable area, preventing their migration to the butterfly valve. This scheme combines fluid dynamics and temperature control design to achieve active enrichment and efficient condensation of volatiles, avoiding the randomness of passive adsorption. The TiO2-based hydrophobic coating prepared using the sol-gel method possesses both anti-adhesion and photocatalytic degradation functions for residues, extending maintenance cycles.

[0042] This system eliminates the risk of condensation on the butterfly valve surface, improving valve reliability. High-temperature airflow carries photoresist volatiles into the cold trap area. Due to the vortex generated by the bent structure, the volatiles accumulate on the inner wall of the cold trap. The volatiles then pass through multiple stages of condensation plates. High-boiling-point components condense in the high-temperature section, while low-boiling-point components are captured in the low-temperature section, achieving graded collection, reducing process contamination, and ensuring wafer yield. It also extends the PM cycle and reduces maintenance frequency and overall costs.

[0043] The above are merely embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A cold trap device for preventing photoresist from condensing on the butterfly valve of an activation furnace, characterized in that, include: A cylindrical outer shell, with an airflow inlet on its side wall and an airflow outlet at its top; A condenser plate, disposed within the cavity of the cylindrical outer shell, includes an airflow inlet, an airflow outlet, and multiple stages of condenser plates. The multi-stage condenser plates are arranged sequentially from the airflow inlet to the airflow outlet, and have a temperature that gradually decreases according to a predetermined temperature gradient, so that the airflow is condensed in stages.

2. The cold trap device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to claim 1, characterized in that, The cold trap device is connected to the bend in the airflow pipe upstream of the butterfly valve through the airflow inlet and outlet of the cylindrical outer shell.

3. The cold trap device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to claim 1, characterized in that, The relative positions of the multi-stage condenser plates are arranged in a spiral or staggered pattern.

4. The cold trap device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to claim 1, characterized in that, The inner wall of the cylindrical shell contains a multi-layer heat exchange structure, which creates a temperature difference of 50~100°C between the inner wall of the cylindrical shell and the high-temperature zone of the airflow pipeline upstream of the butterfly valve.

5. The cold trap device for preventing photoresist from condensing on the activation furnace butterfly valve according to claim 1, characterized in that, Also includes: A flow divider is disposed within the cavity of the cylindrical outer shell near the airflow inlet to directionally divide the airflow flowing into the airflow inlet.

6. The cold trap device for preventing photoresist from condensing on the activation furnace butterfly valve according to claim 1, characterized in that, The pipe heating is cooled by a multi-stage condenser plate.

7. The cold trap device for preventing photoresist from condensing on the activation furnace butterfly valve according to claim 1, characterized in that, The cold trap device is integrated into the internal cavity of the butterfly valve.

8. The cold trap device for preventing photoresist from condensing on the butterfly valve of the activation furnace according to claim 1, characterized in that, Also includes: A ceramic fiber insulation layer is attached to the outer wall of the cylindrical outer shell.

9. The cold trap device for preventing photoresist from condensing on the activation furnace butterfly valve according to claim 1, characterized in that, Also includes: A hydrophobic nano-coating is applied to the inner wall of the cylindrical outer shell.

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