Silicon wafer cooling system used after RTP operation

Abstract

The utility model discloses a silicon wafer cooling system after RTP operation, which comprises a cooling base for bearing a silicon wafer and a sealing cover covering the cooling base, a cooling chamber is enclosed by the sealing cover and the cooling base, and the top wall of the sealing cover is provided with an air inlet valve used for being connected with an external cooling air source. The utility model provides a silicon wafer cooling system, and solves the problems of potential increase of particle problems before and after operation and low cooling efficiency after silicon wafer operation in the prior art.

Description

Technical Field

[0001] The utility model relates to the technical field of RTP rapid heat treatment, in particular to a cooling system after the RTP rapid heat treatment is completed. Background Art

[0002] When semiconductor annealing silicon wafers are injected with impurity ions, the high-energy incident ions will collide with atoms on the semiconductor lattice, causing some lattice atoms to shift, resulting in a large number of vacancies, which will cause the atoms in the injected area to be arranged in a disordered manner or become an amorphous area. Therefore, after ion implantation, the semiconductor must be annealed at a certain temperature to restore the crystal structure and eliminate defects. At the same time, annealing also has the function of activating donor and acceptor impurities, that is, some impurity atoms in interstitial positions are annealed to move into replacement positions.

[0003] RTP (Rapid Thermal Processing) is a method of heating the entire silicon wafer to a temperature range of 400-1300°C in a very short time. Compared with furnace annealing, it has the characteristics of less thermal budget, less movement of impurities in silicon, less contamination and shorter processing time. However, most RTP equipment does not install cooling devices for the silicon wafers after the operation is completed in the cooling area of ​​the silicon wafers, so the cooling efficiency of the silicon wafers after the operation is low. Utility Model Content

[0004] In order to overcome the deficiencies in the prior art, the utility model provides a silicon wafer cooling system after RTP operation, which has the advantages of high cooling efficiency and the like.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A silicon wafer cooling system after RTP operation includes a cooling base for carrying silicon wafers and a sealing cover arranged on the cooling base, wherein the sealing cover and the cooling base enclose a cooling chamber, and an air inlet valve for connecting to an external cooling air source is arranged on the top wall of the sealing cover.

[0007] By adopting the above-mentioned technical scheme, it can be known that a sealing cover is provided on the cooling base to form a relatively closed cooling chamber. An air intake valve is provided on the top wall of the sealing cover. Due to the setting of the sealing cover, the airflow blown out by the air intake valve can form a circulating convection motion inside the cooling chamber, which can not only effectively cool down the surface of the silicon wafer and fully take away the heat from the surface of the silicon wafer, but also the airflow will further take away impurity particles and reduce the residual particles on the surface of the silicon wafer.

[0008] Furthermore, the air intake valve has a central air passage and a plurality of branch air passages surrounding the central air passage, the central air passage is vertically arranged, and the plurality of branch air passages are inclined in a direction away from the central air passage.

[0009] By adopting the above-mentioned technical solution, the gas blown out of the central airway is arranged vertically, which plays a major cooling role and can take away the heat from the surface of the silicon wafer more quickly. The branch airways surround the central airway and are inclined away from the central airway, so that the gas blown out of the branch airways forms a surrounding multi-directional airflow around the silicon wafer, which can form convection around the silicon wafer. This multi-directional airflow can cover the surface of the silicon wafer more comprehensively, avoid local overheating, and further improve the uniformity of cooling. At the same time, the multi-directional airway blowing will take away the particles on the surface of the silicon wafer and blow to the corners at the same time, and will not move repeatedly with the convection movement formed in the sealing cover.

[0010] Furthermore, the sealing cover is provided with an exhaust hole.

[0011] By adopting the above-mentioned technical solution, it can be known that in order to balance the air pressure inside and outside the sealing cover and ensure the stable cooling process, exhaust holes are set on the sealing cover. These exhaust holes allow the gas in the cooling process to be discharged in time, avoiding the accumulation of gas in the sealing cover and further protecting the cooling system.

[0012] Furthermore, the exhaust hole is located at the edge of the top wall of the sealing cover, and the air intake valve is located at the center of the top wall of the sealing cover.

[0013] By adopting the above-mentioned technical solution, it can be seen that limiting the position of the exhaust holes helps to optimize the airflow path and reduce the direct interference of the airflow on the silicon wafer cooling area. The airflow in the sealing cover will naturally flow to the edge during the rising process, thereby stabilizing the airflow path and avoiding chaotic flow of the airflow inside the sealing cover, further making the heat dissipation on the silicon wafer surface more uniform and improving the cooling stability.

[0014] Furthermore, the bottom surface of the side wall of the sealing cover extends upward to form a transfer port for silicon wafers to enter and exit, and a cover plate for opening and closing the transfer port is hingedly connected to the side wall of the sealing cover above the transfer port.

[0015] By adopting the above-mentioned technical solution, it can be seen that through the cooperation between the transmission port and the cover plate, an entry and exit channel is provided for the silicon wafer while ensuring the relative sealing of the sealing cover, further effectively preventing external air and impurities from entering the sealing cover, reducing the risk of silicon wafer contamination.

[0016] Furthermore, the cooling base is provided with a guide groove, and the guide groove extends from a position corresponding to the transmission port toward the center direction of the cooling base.

[0017] By adopting the above-mentioned technical solution, it can be seen that a guide groove for accommodating the manipulator is provided on the cooling base, which provides sufficient space for the manipulator to move. The extension of the guide groove enables the manipulator to take out or put in the silicon wafer from the cooling base more smoothly and steadily when placing the silicon wafer, thereby avoiding abnormal falling or damage of the silicon wafer due to space limitations during operation, further ensuring the safety of the silicon wafer and improving the cooling efficiency.

[0018] Furthermore, a first temperature sensor is provided on the side wall of the sealing cover, a temperature measuring end of the first temperature sensor is located in the cooling chamber, and the temperature measuring end detects the temperature of the silicon wafer in a non-contact manner.

[0019] By adopting the above-mentioned technical solution, it can be seen that during the cooling process, the airflow diverges from the center to the edges of the silicon wafer, which will cause the cooling rate in the center of the silicon wafer to be faster than that in the edge area. By adding a first temperature sensor, the surface temperature of the edge of the silicon wafer can be monitored in real time and accurately, which can ensure that the silicon wafer always maintains an appropriate temperature distribution during the cooling process to avoid local overheating or overcooling. The use of a non-contact sensor can avoid any potential physical damage to the silicon wafer while being able to respond quickly and accurately read the temperature, further ensuring the overall cooling uniformity of the silicon wafer and improving the cooling efficiency.

[0020] Furthermore, a second temperature sensor is provided on a portion of the cooling base located outside the sealing area of ​​the sealing cover, for detecting the temperature of the cooling base.

[0021] By adopting the above-mentioned technical solution, it can be known that the cooling base exchanges heat with the silicon wafer and takes away the heat from the silicon wafer, thereby achieving cooling of the silicon wafer. Therefore, by adding a second temperature measuring sensor to the cooling base to monitor the actual temperature of the cooling base, it can be determined whether the cooling base is in a suitable operating temperature range to avoid the temperature of the cooling base being too high or too low, which affects the cooling effect of the silicon wafer. Furthermore, in order to make the temperature measurement more rigorous, it is necessary to place it outside the sealing area of ​​the sealing cover to avoid interference from hot air in the sealing cover and errors.

[0022] Furthermore, a plurality of limiting columns are provided in the area sealed by the sealing cover on the cooling base, and the plurality of limiting columns define a silicon wafer placement area on the cooling base.

[0023] By adopting the above-mentioned technical solution, it can be seen that the setting of the limit columns on the cooling base not only defines the silicon wafer placement area, but also limits the movement of the silicon wafer. During the cooling process, the silicon wafer may be displaced or slide due to airflow impact, temperature changes or other external factors. This displacement or sliding will not only affect the cooling effect, but may also cause damage to the silicon wafer. Therefore, by adding limit columns to limit the movement range of the silicon wafer, displacement or sliding during the cooling process can be prevented, ensuring that it maintains a relatively stable position during the cooling process.

[0024] Furthermore, the sealing cover is a transparent cover.

[0025] By adopting the above-mentioned technical solution, it can be seen that the transparent material enables the staff to clearly observe the situation inside the cooling base, including the cooling status of the silicon wafer, the flow of the cooling medium, etc., which facilitates the timely discovery and resolution of potential problems and improves the maintainability and reliability of the system.

[0026] The beneficial effects of the utility model are: (1) improving the cooling efficiency of the silicon wafer after annealing; and (2) optimizing the cleanliness problem of the silicon wafer surface in the cooling zone after annealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is an overall schematic diagram of the utility model;

[0028] Figure 2 It is a specific framework diagram of the utility model;

[0029] Figure 3 It is a top view structural diagram of the utility model;

[0030] Figure 4 It is the specific conceptual design of the purge gas circuit of the utility model;

[0031] In the figure: 1. cooling base; 11. sealing cover; 12. silicon wafer placement area; 13. limiting column; 14. first temperature sensor; 15. second temperature sensor; 16. guide groove; 111. transmission port; 112. cover plate; 113. air inlet valve; 1131. central air duct; 1132. branch air duct; 1133. air path through hole; 114. exhaust hole. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0033] Embodiment 1:

[0034] like Figure 2 As shown, a silicon wafer cooling system after RTP operation includes a cooling base 1 for supporting silicon wafers and a sealing cover 11 covered on the cooling base 1, wherein the sealing cover 11 and the cooling base 1 enclose a cooling chamber, and an air inlet valve 113 for connecting to an external cooling air source is provided on the top wall of the sealing cover 11.

[0035] It can be understood that a sealing cover 11 is provided on the cooling base 1 to form a relatively closed cooling chamber. An air inlet valve 113 is provided on the top wall of the sealing cover 11. Due to the setting of the sealing cover 11, the air flow blown out by the air inlet valve 113 can form a circulating convection motion inside the cooling chamber, which can not only effectively cool down the surface of the silicon wafer and fully take away the heat from the surface of the silicon wafer, but also the air flow will further take away impurity particles and reduce the residual particles on the surface of the silicon wafer.

[0036] Preferably, the sealing cover 11 is made of a heat-resistant, insulating, transparent and visible material.

[0037] It can be understood that the heat-resistant insulation material ensures that the sealing cover 11 still maintains its structural integrity and functionality in a high temperature environment, effectively preventing heat from being transferred to the outside, thereby improving the safety and stability of the system. The transparent visibility allows the staff to clearly observe the internal conditions of the cooling base 1, including the cooling status of the silicon wafer, the flow of the cooling medium, etc., which facilitates the timely discovery and resolution of potential problems, thereby improving the maintainability and reliability of the system. Similarly, the cooling base 1 is also preferably made of heat-resistant insulation material, such as acrylic material.

[0038] Preferably, in this embodiment, the sealing cover 11 is rectangular, and is provided with four exhaust holes 114 , which are located at the corners of the top wall of the sealing cover 11 .

[0039] It can be understood that in order to balance the air pressure inside and outside the sealing cover 11 and ensure the stable cooling process, an exhaust hole 114 is set on the sealing cover 11. These exhaust holes 114 allow the gas in the cooling process to be discharged in time, avoiding the accumulation of gas in the sealing cover 11, and further protecting the cooling system. The limitation of the position of the exhaust holes 114 helps to optimize the path of the airflow and reduce the direct interference of the airflow on the cooling area of ​​the silicon wafer. The airflow in the sealing cover 11 will naturally flow to the corners during the rising process, which stabilizes the path of the airflow and avoids the chaotic flow of the airflow inside the sealing cover 11, further making the heat dissipation on the surface of the silicon wafer more uniform and improving the cooling stability.

[0040] Furthermore, the bottom surface of the side wall of the sealing cover 11 extends upward to form a transfer port 111 for silicon wafers to enter and exit, and a cover plate 112 for opening and closing the transfer port 111 is hingedly connected to the side wall of the sealing cover 11 above the transfer port 111 .

[0041] It can be understood that, through the cooperation between the transmission port 111 and the cover plate 112, an entry and exit channel is provided for the silicon wafer while ensuring the relative sealing of the sealing cover 11, further effectively preventing external air and impurities from entering the sealing cover 11, reducing the risk of silicon wafer contamination.

[0042] Preferably, considering the size of the silicon wafer and the smoothness of transmission, the length of the transmission port 111 should be at least not less than the diameter of the silicon wafer placement area 12, so as to ensure that the silicon wafer will not be obstructed during the transmission process. At the same time, the height of the transmission port 111 should be at least not less than the maximum thickness of the silicon wafer, so as to ensure that the silicon wafer can be smoothly in and out, avoid collision or jamming during the transmission process, and further improve the safety of the cooling system.

[0043] Preferably, a groove can be provided on the cooling base 1 for assembly with the sealing cover 11. In order to ensure the best sealing performance, a seal is arranged in the groove. The sealing cover 11 can be detachably installed on the cooling base 1 by being embedded in the groove. This not only facilitates the inspection of whether the internal structure is damaged, but also allows for easy repair or replacement when necessary, thereby greatly improving the maintenance efficiency and convenience of the system.

[0044] Preferably, four limiting columns 13 are provided in the area sealed by the sealing cover 11 on the cooling base 1 , and the limiting columns 13 define a silicon wafer placement area 12 on the cooling base 1 .

[0045] It can be understood that the setting of the limit column 13 on the cooling base 1 not only defines the silicon wafer placement area 12, but also limits the movement of the silicon wafer. During the cooling process, the silicon wafer may be displaced or slide due to airflow impact, temperature changes or other external factors. This displacement or sliding will not only affect the cooling effect, but may also cause damage to the silicon wafer. Therefore, by adding the limit column 13 to limit the movement range of the silicon wafer, displacement or sliding during the cooling process can be prevented, ensuring that it maintains a relatively stable position during the cooling process.

[0046] Preferably, the material of the limiting column 13 should be selected with high temperature resistance and excellent flexibility to ensure that it can still maintain stable physical properties in a high temperature environment. While limiting the position of the silicon wafer, its material should ensure that it will not cause scratches or damage to the surface of the silicon wafer, thereby ensuring the integrity and safety of the silicon wafer during the cooling process, which not only meets the limiting requirements, but also ensures the protection of the silicon wafer.

[0047] Preferably, the silicon wafer placement area 12 is located in the center, which is the best choice. It can ensure that the silicon wafer obtains a uniform cooling effect during the cooling process, help reduce potential problems caused by silicon wafer position offset or instability, and further improve the stability and reliability of the system.

[0048] Embodiment 2:

[0049] On the basis of Example 1, the air intake valve 113 has a central air passage 1131 and a plurality of branch air passages 1132 surrounding the central air passage 1131 , the central air passage 1131 is vertically arranged, and the plurality of branch air passages 1132 are inclined in a direction away from the central air passage 1131 .

[0050] It can be understood that the gas blown out of the central air duct 1131 is arranged vertically, which plays a major cooling role and can quickly take away the heat from the surface of the silicon wafer. The branch air duct 1132 surrounds the central air duct 1131 and deviates away from the central air duct 1131, so that the gas blown out of the branch air duct 1132 forms a surrounding multi-directional airflow around the silicon wafer, which can form convection around the silicon wafer. This multi-directional airflow can cover the surface of the silicon wafer more comprehensively, avoid local overheating, and further improve the uniformity of cooling. At the same time, the multi-directional air duct blowing will take away the particles on the surface of the silicon wafer and blow them to the corners at the same time, and will not move repeatedly with the convection movement formed in the sealing cover 11.

[0051] Preferably, in this embodiment, a central airway 1131 and four branch airways 1132 are provided. The central airway 1131 is a cylinder, and the branch airways 1132 are cones and are correspondingly distributed around the central airway 1131. Each airway structure is internally connected to the airway according to the original outer edge trend, that is, the central cylinder opens an airway to the silicon wafer placement area 12, and the cone airway formed by the four-point cone is connected to the airway along the corresponding inclined surface. During the gas purge process, the gas enters through the central airway 1131, and the internal gas is diverted through the branch airway 1132. Air is blown through the airway hole. Since the branch airway 1132 is a vertebral body and forms a certain inclination angle with the central airway 1131, the branch airway 1132 has a certain directionality. Therefore, when blowing out through the airway hole 1133, it will be blown out along the direction of the branch airway 1132. In this embodiment, only one central airway 1131 and four branch airways 1132 are provided. The central airway 1131 is a cylinder and the branch airways 1132 are cones for illustration and display. There is no specific number and shape limitation for this. It is only necessary to achieve that the branch airway 1132 has a certain directionality.

[0052] Embodiment 3:

[0053] On the basis of Embodiment 1, a first temperature sensor 14 is provided on the side wall of the sealing cover 11 , and a temperature measuring end of the first temperature sensor 14 is located in the cooling chamber, and the temperature measuring end detects the temperature of the silicon wafer in a non-contact manner.

[0054] It can be understood that during the cooling process, the air flow diverges from the center to the edges of the silicon wafer, which will cause the cooling rate in the center of the silicon wafer to be faster than that in the edge area. By adding a first temperature sensor 14, the surface temperature of the edge of the silicon wafer can be monitored in real time and accurately, which can ensure that the silicon wafer always maintains an appropriate temperature distribution during the cooling process, avoids the occurrence of local overheating or overcooling, ensures the overall cooling uniformity of the silicon wafer, and improves the cooling efficiency.

[0055] Preferably, the first temperature sensor 14 may be a non-contact infrared temperature measuring element, which can monitor the surface temperature of the silicon wafer in real time and accurately without direct contact with the silicon wafer, thereby avoiding contamination or damage caused by contact.

[0056] Preferably, the temperature threshold can also be set for the non-contact infrared temperature measuring device. When the edge temperature of the silicon wafer reaches or exceeds the set threshold, the airflow parameters, such as flow rate, speed, etc., can be automatically adjusted. At the same time, the temperature threshold setting can also be used to trigger an alarm or stop the cooling process to prevent the silicon wafer from being damaged due to excessive cooling.

[0057] Preferably, a hole is provided on the side wall of the sealing cover 11 near the silicon wafer for placing the first temperature sensor 14. The temperature measuring end of the first temperature sensor 14 is located in the cooling chamber, and the other end is the transmission end, which is placed outside the cooling chamber for connecting to the data receiving device.

[0058] Preferably, in the present embodiment, two first temperature measuring components are selected to ensure the stability of temperature measurement, but in actual use, at least one is maintained, and there is no specific limitation on this.

[0059] Furthermore, a second temperature sensor 15 is provided on the portion of the cooling base 1 outside the sealing area of ​​the sealing cover 11 for detecting the temperature of the cooling base 1 .

[0060] It can be understood that the cooling base 1 exchanges heat with the silicon wafer and takes away the heat from the silicon wafer, thereby cooling the silicon wafer. Therefore, by adding a second temperature sensor 15 to the cooling base 1 to monitor the actual temperature of the cooling base 1, it can be determined whether the cooling base 1 is in a suitable operating temperature range to avoid the temperature of the cooling base 1 being too high or too low, which affects the cooling effect of the silicon wafer. Furthermore, in order to make the temperature measurement more rigorous, it is necessary to place it outside the sealing area of ​​the sealing cover 11 to avoid interference from hot air in the sealing cover 11 and errors.

[0061] Preferably, the second temperature sensor 15 can be a cooling water temperature monitoring device, which can maintain a stable interconnected state with the first temperature sensor 14 to ensure the real-time and accuracy of data interaction, so that the entire cooling system can fully monitor the temperature state of the silicon wafer and its cooling water, thereby ensuring that the silicon wafer is always in an ideal temperature range during the cooling process, thereby improving the cooling efficiency of the cooling operation.

[0062] Furthermore, a guide groove 16 for a manipulator is provided on the cooling base 1 , and the guide groove 16 extends from a position corresponding to the transfer port 111 toward the center of the cooling base 1 .

[0063] It can be understood that the cooling base 1 is provided with a guide groove 16 for accommodating the manipulator, which provides sufficient space for the manipulator to move. The extension of the guide groove 16 enables the manipulator to more smoothly and steadily take out or put in the silicon wafer from the cooling base 1 when placing the silicon wafer, thereby avoiding abnormal falling or damage of the silicon wafer due to space limitations during operation, further ensuring the safety of the silicon wafer and improving the cooling efficiency.

[0064] In the overall operation process, the manipulator transfers the silicon wafer into the sealing cover 11 through the transfer port 111, and then descends to the guide groove 16 to transfer the silicon wafer to the silicon wafer placement area 12. When the manipulator withdraws, the transfer port 111 is closed, and the five-way air channel located above the center of the silicon wafer begins to blow air, and the four silicon wafer limit columns 13 are used to block the possible displacement of the silicon wafer. In the process of forming convection movement, the gas is discharged through the top exhaust hole 114 on the top of the sealing cover 11. At the same time, in this process, the first temperature sensor 14 located on both sides of the silicon wafer monitors the edge temperature of the silicon wafer in real time and transmits data. The heat on the back of the silicon wafer is further conducted through the cooling base 1 and transferred to the cooling base 1 filled with cooling water. The second temperature sensor 15 monitors the temperature of the cooling water in real time and transmits data. After the operation is completed, the components stop working and the silicon wafer is transferred by the manipulator again.

[0065] In addition to the above-mentioned preferred embodiments, the present invention also has other implementation modes. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection requested by the present invention.

Claims

1. A silicon wafer cooling system after RTP operation, characterized in that: It comprises a cooling base for carrying silicon wafers and a sealing cover arranged on the cooling base, wherein the sealing cover and the cooling base enclose a cooling chamber, and an air inlet valve for connecting to an external cooling air source is arranged on the top wall of the sealing cover.

2. A silicon wafer cooling system after RTP operation according to claim 1, characterized in that: The air intake valve comprises a central air passage and a plurality of branch air passages surrounding the central air passage, the central air passage is arranged vertically, and the plurality of branch air passages are inclined in a direction away from the central air passage.

3. A silicon wafer cooling system after RTP operation according to claim 1, characterized in that: The sealing cover is provided with an exhaust hole.

4. A silicon wafer cooling system after RTP operation according to claim 3, characterized in that: The exhaust hole is located at the edge of the top wall of the sealing cover, and the air inlet valve is located at the center of the top wall of the sealing cover.

5. The silicon wafer cooling system after RTP operation according to claim 1, characterized in that: The bottom surface of the side wall of the sealing cover extends upward to form a transfer port for silicon wafers to enter and exit, and a cover plate for opening and closing the transfer port is hingedly connected to the side wall of the sealing cover above the transfer port.

6. A silicon wafer cooling system after RTP operation according to claim 5, characterized in that: The cooling base is provided with a manipulator guide groove, and the manipulator guide groove extends from a position corresponding to the transmission port toward the center direction of the cooling base.

7. The silicon wafer cooling system after RTP operation according to claim 1, characterized in that: A first temperature sensor is disposed on the side wall of the sealing cover. A temperature measuring end of the first temperature sensor is located in the cooling chamber. The temperature measuring end detects the temperature of the silicon wafer in a non-contact manner.

8. The silicon wafer cooling system after RTP operation according to claim 1, characterized in that: A second temperature sensor is provided on the portion of the cooling base outside the sealing area of ​​the sealing cover for detecting the temperature of the cooling base.

9. A silicon wafer cooling system after RTP operation according to any one of claims 1 to 8, characterized in that: A plurality of limiting columns are arranged in the area sealed by the sealing cover on the cooling base, and the plurality of limiting columns define a silicon wafer placement area on the cooling base.

10. A silicon wafer cooling system after RTP operation according to any one of claims 1 to 8, characterized in that: The sealing cover is a transparent cover body.

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