Wafer temperature returning system
By establishing a high vacuum environment in the wafer rewarming system and using inert gas for heating or cooling, the safety and stability issues in the high-temperature or low-temperature wafer rewarming process are solved, and the wafer is stably rewarmed to room temperature.
Patent Information
- Application Number
- CN202511381910.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-25
- Publication Date
- 2026-02-06
AI Technical Summary
In existing technologies, wafers implanted at high or low temperatures are prone to adverse effects on the next process during the warm-up process, or they may be exposed to the atmosphere at low temperatures, resulting in frost formation and product damage or failure.
A wafer rewarming system was designed to achieve a high vacuum environment by connecting a wafer library to a molecular pump, and to use an inert gas to heat or cool the wafer in a heat exchanger, which then contacts the wafer for heat exchange, so as to achieve a stable temperature recovery to room temperature.
This ensures the safety and stability of the wafer during the warm-up process, avoids the adverse effects of high temperature on the next process and the problem of low temperature frosting, and achieves a smooth warm-up of the wafer to room temperature.
Smart Images
Figure CN121487569A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of semiconductor devices, in particular to a wafer re-warming system. BACKGROUND
[0002] The semiconductor component manufacturing technology and the involved process are complex and diverse. Taking an ion implanter as an example, in the ion implantation process, in order to meet the higher process requirements, two processes can be divided into high-temperature implantation and low-temperature implantation. After high-temperature and low-temperature implantation, it is crucial to re-warm the wafer after heat exchange to normal temperature. Specifically, the temperature of the wafer after high-temperature implantation can be as high as 600℃, and if it enters the next process, the high-temperature wafer will have an adverse effect on the next process, so the temperature of the wafer needs to be re-warmed to normal temperature. Similarly, in a low-temperature ion implanter, after low-temperature implantation, the temperature of the wafer can be as low as -120℃, and when entering the next process, the low-temperature wafer will be exposed to the atmosphere. If it is directly exposed to the atmosphere, the wafer will have a serious frosting condition, which will cause damage, failure, etc. of the product. SUMMARY
[0003] The technical problem to be solved by the present application is to provide a wafer re-warming system with compact structure, convenient operation and high stability.
[0004] In order to solve the above technical problems, the technical scheme adopted by the present application is: A wafer re-warming system, comprising: a heat exchanger, a molecular pump and a wafer library for placing a wafer to be re-warmed; the molecular pump is connected to the wafer library through a pipeline to realize vacuumization in the wafer library; the wafer library is provided with a waste discharge pipeline to realize gas discharge in the wafer library; the gas inlet of the heat exchanger is connected with an external inert gas source through an inert gas input pipe, and the gas outlet of the heat exchanger is connected with the wafer library through an inert gas output pipe, the inert gas is heated in the heat exchanger and then transported to the wafer library to contact and heat exchange with the wafer, so as to realize wafer re-warming.
[0005] As a further improvement of the present application, the gas outlet of the heat exchanger is provided with a third temperature sensor for detecting the temperature of the inert gas transported to the wafer library; the gas outlet of the wafer library is provided with a temperature sensor for detecting the temperature of the inert gas after heat exchange with the wafer. The gas outlet of the wafer library is also provided with a vacuum gauge and an angular valve, the vacuum gauge is used to detect the vacuum degree in the wafer library, and when the vacuum degree in the wafer library reaches a preset value, the angular valve is automatically opened to realize gas discharge in the wafer library to the waste discharge pipeline.
[0006] As a further improvement of the present application, the waste discharge pipeline is provided with a waste discharge control valve, and the waste discharge pipeline is connected to a waste discharge main pipe of a plant.
[0007] As a further improvement of the present application, the inert gas input pipe is provided with a one-way valve, a pressure reducing valve and a pressure gauge; the back pressure of the one-way valve is 500-700 Pa to prevent the inert gas in the heat exchanger from flowing back.
[0008] As a further improvement of the present application, the gas outlet of the heat exchanger is provided with a filter.
[0009] As a further improvement of the present application, the filtering precision of the filter is greater than or equal to 0.0015 microns.
[0010] As a further improvement of the present application, the wafer library is provided with a diffuser above the wafer, and the inert gas delivered by the inert gas output pipe is uniformly distributed in the wafer library through the diffuser.
[0011] As a further improvement of the present application, a flapper valve is arranged in the pipeline between the molecular pump and the wafer library.
[0012] As a further improvement of the present application, the inert gas is nitrogen, helium or argon.
[0013] Compared with the prior art, the present application has the following advantages: The wafer re-warming system of the present application connects the wafer library storing the wafer with the molecular pump to establish a high vacuum environment in the wafer library and ensure the safety of the wafer storage; the wafer library is connected with the heat exchanger, and the heat exchanger is connected with the external inert gas source; according to the re-warming requirement of the wafer in the wafer library, the inert gas is delivered to the heat exchanger for heating or cooling, and the heat-exchanged inert gas is delivered to the wafer library to contact and exchange heat with the wafer, thereby realizing the stable re-warming of the wafer to room temperature. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 Fig. 1 is a structural principle schematic diagram of the wafer re-warming system in the embodiment of the present application.
[0015] Fig. 1 is a structural principle schematic diagram of the wafer re-warming system in the embodiment of the present application. DETAILED DESCRIPTION
[0016] The application will be further described below with reference to the accompanying drawings and specific preferred embodiments, but the protection scope of the application is not limited thereby.
[0017] In the description of the application, it should be understood that the terms "side", "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "first", "second", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.
[0018] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to, so that the features with "first" and "second" can include one or more of the features explicitly or implicitly, and in the description of the application, the meaning of "multiple" is two or more, unless otherwise specifically limited.
[0019] Embodiments As Figure 1 shown, the wafer re-warming system of the application comprises a heat exchanger 21, a molecular pump 23 and a wafer library for placing the wafer to be re-warmed 11. The wafer library comprises a first wafer library 10 and a second wafer library 13 arranged side by side, and the molecular pump 23 is connected to the first wafer library 10 and the second wafer library 13 through pipelines to realize vacuum extraction in the first wafer library 10 and / or the second wafer library 13. Moreover, a first plug valve 12 is arranged in the pipeline between the molecular pump 23 and the first wafer library 10, and a second plug valve 24 is arranged in the pipeline between the molecular pump 23 and the second wafer library 13, so as to control the vacuum establishment of the first wafer library 10 and the second wafer library 13 respectively according to different processes and operation procedures. The wafer 11 needs to be re-warmed in a certain vacuum degree environment when it is in a high temperature or low temperature state. The first wafer library 10 is provided with a first exhaust pipe 1, and the second wafer library 13 is provided with a second exhaust pipe 25 to realize the exhaust of the gas in the wafer library. The gas inlet of the heat exchanger 21 is connected to an external inert gas source through an inert gas input pipe 3, and the gas outlet of the heat exchanger 21 is connected to the first wafer library 10 and the second wafer library 13 through an inert gas output pipe 29. After the inert gas is heated in the heat exchanger 21, it is transported into the first wafer library 10 and / or the second wafer library 13 to contact and exchange heat with the wafer 11, so as to realize the re-warming of the wafer 11. In this embodiment, nitrogen is used as the heat exchange gas. In other embodiments, high-purity inert gases such as helium or argon can also be used as the heat exchange medium for wafer re-warming, and multiple wafer libraries can also be connected in parallel to perform wafer re-warming.
[0020] In this embodiment, the high-temperature or low-temperature wafer can be warmed to room temperature by setting the warming time. According to the temperature of the wafer 11, the warming time is different, and the working mode of the heat exchanger 21 is different according to the temperature of the wafer 11. When the temperature of the wafer 11 is lower than 20℃, the working mode of the heat exchanger 21 is heating mode, which is responsible for heating the fluid medium flowing through the heat exchanger 21. When the temperature of the wafer 11 is higher than 50℃, the working mode of the heat exchanger 21 is refrigeration mode, which is responsible for cooling the fluid medium flowing through the heat exchanger 21.
[0021] In this embodiment, the wafer library storing the wafer 11 is connected with the molecular pump 23, so that a high-vacuum environment is established in the wafer library, and the safety of the wafer 11 is ensured. The wafer library is connected with the heat exchanger 21, and the heat exchanger 21 is connected with the external inert gas source. According to the warming requirement of the wafer 11 in the wafer library, the inert gas is delivered to the heat exchanger 21 for heating or cooling. The inert gas after heat exchange is delivered to the wafer library to contact and exchange heat with the wafer 11, so that the wafer 11 is stably warmed to room temperature. The wafer warming system of the present application can be applied to a high-temperature or low-temperature semiconductor device such as a high-temperature or low-temperature ion implanter as a device.
[0022] As shown in Figure 1 The gas outlet of the heat exchanger 21 is provided with a third temperature sensor 20 for detecting the temperature of the inert gas delivered to the wafer library. In the working process, the data of the third temperature sensor 20 is transmitted to the temperature control system, and the temperature control system can control the heat exchanger 21 in real time according to the data, so as to control the temperature of the outlet inert gas within the process temperature range. The gas outlet of the first wafer library 10 is provided with a first temperature sensor 9, and the gas outlet of the second wafer library 13 is provided with a second temperature sensor 14, for detecting the temperature of the inert gas after heat exchange with the wafer 11. The temperature of the inert gas is fed back to the external temperature control system in real time, so as to judge the warming temperature of the wafer 11. When the temperature control system detects that the wafer 11 is cooled from high temperature to room temperature (20℃-25℃) or heated from low temperature to room temperature (22℃-25℃) according to the data fed back by the first temperature sensor 9 and / or the second temperature sensor 14, the wafer warming is completed.
[0023] As shown in Figure 1As shown, the inert gas input pipe 3 is provided with a one-way valve 2, a pressure reducing valve 27 and a pressure gauge 28. The one-way valve 2 is installed between the pressure gauge 28 and the heat exchanger 21 to prevent the high-temperature or low-temperature inert gas in the heat exchanger 21 from flowing back to the inert gas source. For system safety and reliability, the one-way valve 2 has a certain back pressure requirement, and the back pressure of the one-way valve 2 is 500-700 Pa. The pressure reducing valve 27 can automatically regulate the pressure. When the heat exchanger 21 is working, the gas temperature at the outlet of the heat exchanger 21 is also related to the pressure of the gas at the inlet of the heat exchanger 21. In order to achieve faster wafer 11 re-warming effect, the pressure gauge 28 transmits the pressure data to the temperature control system, and the temperature control system combines the data of the pressure gauge 28 and the third temperature sensor 20 to control the pressure reducing valve 27, and performs closed-loop temperature control, which can quickly and accurately control the inert gas temperature at the required process temperature.
[0024] As shown in Figure 1 , the outlet of the heat exchanger 21 is provided with a filter 26, and the filtering accuracy of the filter 26 is ≥0.0015 μm. That is, particles with a particle size greater than 0.0015 μm will be isolated and will not enter the wafer library with the inert gas to cause particle contamination of the wafer 11.
[0025] As shown in Figure 1 , the outlet of the first wafer library 10 is also provided with a first vacuum gauge 6 and a first angle valve 8, and the outlet of the second wafer library 13 is also provided with a second vacuum gauge 17 and a first angle valve 15. The vacuum gauge is used to detect the vacuum degree in the wafer library. When the vacuum degree in the wafer library reaches the preset value, the angle valve is automatically opened to realize the exhaust of the gas in the wafer library to the exhaust pipe.
[0026] As shown in Figure 1 , the first exhaust pipe 1 is provided with a first exhaust control valve 7, and the second exhaust pipe 25 is provided with a second exhaust control valve 16, and the first exhaust pipe 1 and the second exhaust pipe 25 are connected to the exhaust main pipe 22 of the plant. In order to prevent the exhaust gas from flowing back to the wafer library and causing contamination of the wafer 11 or damage to the product, the first exhaust control valve 7 and the second exhaust control valve 16 are both one-way valves and have a certain back pressure.
[0027] As shown in Figure 1As shown, the first wafer library 10 is provided with a first diffuser 5, and the second wafer library 13 is provided with a second diffuser 18. The first diffuser 5 and the second diffuser 18 are both located above the wafer 11. The inert gas output pipe 29 transports the inert gas which is uniformly distributed in the wafer library through the diffusers. At the same time, the first diffuser 5 and the second diffuser 18 also have a filtering function, which filters the high-pressure inert gas twice to prevent the high-pressure inert gas from being contaminated during transportation and causing the wafer 11 to be contaminated. At the same time, the first diffuser 5 and the second diffuser 18 can also homogenize the high-pressure inert gas, weaken the pressure, and suppress dust raising. The high-pressure inert gas will not directly blow onto the wafer 11, causing the position of the wafer 11 to change, and will not cause dust raising in the wafer library, causing the wafer 11 to be contaminated by particles.
[0028] As shown in Figure 1 The connecting pipe between the inert gas output pipe 29 and the first diffuser 5 is provided with a first air inlet valve 4, and the connecting pipe between the inert gas output pipe 29 and the second diffuser 18 is provided with a second air inlet valve 19. When the first wafer library 10 needs to be warmed up, the first air inlet valve 4 is opened, and when the second wafer library 13 needs to be warmed up, the second air inlet valve 19 is opened. Similarly, when the first wafer library 10 establishes high vacuum, the first air inlet valve 4 is closed, and when the second wafer library 13 establishes high vacuum, the second air inlet valve 19 is closed. During warming up, the first air inlet valve 4, the second air inlet valve 19, the first angle valve 8, the second angle valve 15, and the first vacuum gauge 6, the second vacuum gauge 17 are used in cooperation. Taking the warming up of the first wafer library 10 as an example, when the wafer 11 is warmed up in the first wafer library 10, the high-pressure inert gas after heat exchange through the heat exchanger 21 is filled into the first wafer library 10 through the first diffuser 5. At this time, the pressure in the first wafer library 10 rises, and when the first vacuum gauge 6 detects that the vacuum degree is ≥7.62E+2, the first angle valve 8 of the first wafer library 10 is opened. The high-pressure inert gas after heat exchange with the wafer 11 passes through the first angle valve 8 of the first wafer library 10, and then the high-pressure inert gas opens the first waste control valve to be discharged into the first waste pipe 1 and then reaches the waste main pipe 22 at the factory end. Through the mutual cooperation of the vacuum gauge, the temperature sensor, and the waste control valve, the safe and reliable operation of the entire warming up system is monitored, and at the same time, data can be transmitted to the external temperature control system for mutual interaction to achieve better warming up effect.
[0029] The running process of the wafer warming up system of the embodiment is as follows: First, the first inlet valve 4, the second inlet valve 19, the first angle valve 8, and the second angle valve 15 are closed. A high vacuum environment is established in the first wafer storage 10 and the second wafer storage 13 via the molecular pump 23, the first gate valve 12, and the second gate valve 24. The vacuum level is detected using the first vacuum gauge 6 and the second vacuum gauge 17. Once the first wafer storage 10 and the second wafer storage 13 reach the preset vacuum level, the high-temperature or low-temperature wafers requiring rewarming are transferred to the first wafer storage 10 and the second wafer storage 13. After the wafer transfer is completed, the corresponding gate valves are closed. Then, according to the process and temperature requirements, the heat exchanger 21 is switched to high-temperature or low-temperature mode. When high-temperature wafers need rewarming, the heat exchanger 21 is in low-temperature mode; when low-temperature wafers need rewarming, the heat exchanger 21 is in high-temperature mode. Inert gas enters the heat exchanger 21, exchanges heat, and is then delivered to the first wafer storage 10 and the second wafer storage 13. Simultaneously, the system automatically adjusts the inert gas inlet pressure. When the first vacuum gauge 6 and the second vacuum gauge 17 reach 7.62E+2, the first angle valve 8 and the second angle valve 15 are opened. At this time, the rewarming process begins. When the rewarming time reaches the set time, and the temperature change trends of the first temperature sensor 9 and the second temperature sensor 14 meet the requirements, the first angle valve 8 and the second angle valve 15 are closed, the first inlet valve 4 and the second inlet valve 19 are closed, and the heat exchanger 21 is shut down. The above describes the entire wafer rewarming process.
[0030] The temperature change trends of the first temperature sensor 9 and the second temperature sensor 14 are crucial in the system, serving as a key technical indicator for ensuring the safety and reliability of the entire temperature recovery process. When the high-temperature wafer needs to be warmed to room temperature or below 50°C, the temperature trends of the first temperature sensor 9 and the second temperature sensor 14 show an initial increase followed by a decrease to room temperature or below 50°C. Conversely, when the low-temperature wafer needs to be warmed to room temperature, the temperature trends of the first temperature sensor 9 and the second temperature sensor 14 show an initial decrease followed by an increase to room temperature or above room temperature. This detection process does not collect specific temperature data values, but rather captures the temperature change trend throughout the entire temperature recovery process.
[0031] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.
Claims
1. A wafer warming system, characterized in that, include: The equipment includes a heat exchanger (21), a molecular pump (23), and a wafer storage container for placing the wafers (11) to be reheated. The molecular pump (23) is connected to the wafer storage container via a pipe to achieve vacuuming inside the wafer storage container. The wafer storage container is equipped with a waste discharge pipe to achieve gas discharge from the wafer storage container. The inlet of the heat exchanger (21) is connected to an external inert gas source via an inert gas input pipe (3), and the outlet of the heat exchanger (21) is connected to the wafer storage container via an inert gas output pipe (29). After the inert gas undergoes heat exchange in the heat exchanger (21), it is transported to the wafer storage container to contact and exchange heat with the wafers (11) to achieve reheating of the wafers (11).
2. The wafer warming system according to claim 1, characterized in that, The heat exchanger (21) is equipped with a third temperature sensor (20) at its outlet to detect the temperature of the inert gas delivered to the wafer storage; the wafer storage is equipped with a temperature sensor at its outlet to detect the temperature of the inert gas after heat exchange with the wafer (11).
3. The wafer warming system according to claim 2, characterized in that, The gas outlet of the film storage is also equipped with a vacuum gauge and an angle valve. The vacuum gauge is used to detect the vacuum level inside the film storage. When the vacuum level inside the film storage reaches a preset value, the angle valve is automatically opened to allow the gas inside the film storage to be discharged into the waste discharge pipeline.
4. The wafer warming system according to claim 3, characterized in that, The waste discharge pipeline is equipped with a waste discharge control valve, and the waste discharge pipeline is connected to the waste discharge main pipe (22) at the plant end.
5. The wafer warming system according to any one of claims 1 to 4, characterized in that, The inert gas inlet pipe (3) is equipped with a one-way valve (2), a pressure reducing valve (27) and a pressure gauge (28); the back pressure of the one-way valve (2) is 500-700 Pa to prevent the inert gas in the heat exchanger (21) from flowing back.
6. The wafer warming system according to any one of claims 1 to 4, characterized in that, The heat exchanger (21) is equipped with a filter (26) at its outlet.
7. The wafer warming system according to claim 6, characterized in that, The filter (26) has a filtration accuracy of ≥0.0015μm.
8. The wafer warming system according to any one of claims 1 to 4, characterized in that, The wafer library is equipped with a diffuser located above the wafer (11). The inert gas delivered by the inert gas output pipe (29) is evenly distributed in the wafer library through the diffuser.
9. The wafer warming system according to any one of claims 1 to 4, characterized in that, A gate valve is installed in the pipeline between the molecular pump (23) and the tablet library.
10. The wafer warming system according to any one of claims 1 to 4, characterized in that, The inert gas is nitrogen, helium, or argon.