Annealing furnace for batch processing of semiconductor wafers

Abstract

The invention relates to an annealing furnace for batch processing of semiconductor wafers, and belongs to the technical field of semiconductor wafer processing, the annealing furnace comprises a furnace body, the end part of the furnace body is fixedly connected with a connecting frame, one end of the connecting frame is fixedly connected with a preheating box, and a heating pipe is arranged in the furnace body. Through the arrangement of the first mounting plate, the second mounting plate, an air suction cover, a heat storage tank and a second air supply pipe, after multiple batches of wafers are fed to the first mounting plate and the second mounting plate respectively, when the wafers on the second mounting plate are normally processed in the furnace body, heat in the furnace is absorbed through the air suction cover, and the heat in the furnace body is fully utilized. And under the arrangement of the electrostatic dust collection box, the recovered heat is purified, and the purified heat is conveyed into the heat storage tank and the second air supply pipe to preheat the wafer in the preheating box, so that the situation that the wafer on the first mounting plate is directly input into the furnace, the temperature difference is large, and the wafer processing quality is affected is prevented.

Description

Technical Field

[0001] This invention relates to the field of semiconductor wafer processing technology, and more specifically, to an annealing furnace for batch processing of semiconductor wafers. Background Technology

[0002] Semiconductor wafers are a fundamental material used to manufacture semiconductor devices. They are typically made of single-crystal silicon and have a highly pure and uniform structure. During semiconductor manufacturing, semiconductor devices are fabricated on the wafer through a series of process steps. Semiconductor wafers are one of the most important materials in the semiconductor industry, and their quality and fabrication process have a significant impact on device performance. In the current technology, annealing is required on semiconductor wafers during the processing of semiconductor wafers to improve the stability of subsequent processing.

[0003] In the prior art, CN 222783920 U discloses an annealing furnace for batch processing of semiconductor wafers, relating to the field of semiconductor wafer processing technology. The furnace includes an annealing furnace with an upper heating tube and a lower heating tube fixedly connected inside. An opening is provided on the bottom side wall of the furnace, and a rotating shaft is rotatably connected to the bottom inner wall. A turntable is fixedly connected to the shaft, and a motor is fixedly connected to the bottom of the furnace. This invention places semiconductor wafers inside a placement slot and clamps them in a slot on the side wall of a clamping plate. The output shaft of the motor rotates, driving the rotating shaft to rotate via a bevel gear. The rotating shaft then drives the turntable to rotate, extending the placement slot containing the semiconductor wafers into the interior of the annealing furnace. The upper and lower heating tubes anneal the semiconductor wafers, and the heat-conducting fins improve heat conduction and annealing efficiency.

[0004] However, existing annealing furnaces often directly feed wafers into the furnace for alternating wafer processing. This results in poor preheating of batches of wafers to be processed, leading to a large temperature difference between the wafers and the furnace, which affects the quality of the annealing process. Furthermore, the furnace's heat recovery and purification effect during preheating is not high, reducing the versatility of heat utilization. Additionally, the heat spraying effect on the wafers during annealing is poor, and the wafer evacuation is not efficient, creating blind spots in the wafer processing and reducing the quality of wafer processing. This does not meet user needs. Therefore, we propose an annealing furnace for batch processing of semiconductor wafers. Summary of the Invention

[0005] To address the problems mentioned in the background, the present invention provides an annealing furnace for batch processing of semiconductor wafers, thereby solving the problems mentioned in the background art, such as low preheating performance of batch wafers to be processed alternately in the annealing furnace, low effect of furnace temperature purification and recovery, reduced multifunctionality of furnace heat utilization, poor effect of heat spraying to all directions of the wafers, and low performance of wafer levitation processing.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0007] An annealing furnace for batch processing of semiconductor wafers includes a furnace body, a connecting frame fixedly connected to one end of the furnace body, a preheating box fixedly connected to one end of the connecting frame, a heating tube disposed inside the furnace body, a first electric push rod disposed at the end of the preheating box, a first mounting plate fixedly connected to one end of the first electric push rod, a connecting rod fixedly connected to the end of the first mounting plate, a second mounting plate fixedly connected to one end of the connecting rod, a placement block fixedly connected to the top of the second mounting plate, and a wafer body placed on the surface of the placement block;

[0008] The outer wall of the second mounting plate is slidably connected to a lifting frame, and the outer wall of the lifting frame is slidably connected to a positioning rod. One end of the positioning rod is fixedly connected to a positioning block located on one side of the wafer body.

[0009] An air suction hood is installed at the top of the inner cavity of the furnace body. The top of the air suction hood is fixedly connected to an electrostatic dust removal box located at the top of the furnace body via a connecting pipe. The outer wall of the electrostatic dust removal box is connected to a conveying pipe via a connecting pump. One end of the conveying pipe is fixedly connected to a heat storage tank located on the outer wall of the furnace body. The outer wall of the heat storage tank is fixedly connected to a second air supply pipe fixedly connected to the top of the preheating box via a connecting pump. With the arrangement of the first mounting plate, the second mounting plate, the air suction hood, the heat storage tank, and the second air supply pipe, after multiple batches of wafers are respectively fed onto the first mounting plate and the second mounting plate, the wafers on the second mounting plate are processed normally in the furnace body. The air suction hood absorbs the heat in the furnace body, and with the electrostatic dust removal box, the recovered heat is purified and transported to the heat storage tank and the second air supply pipe to preheat the wafers in the preheating box. This prevents the wafers on the first mounting plate from being directly input into the furnace body, which would result in a large temperature difference and affect the quality of wafer processing.

[0010] Preferably, the heating tubes are arranged in a ring shape and distributed in a straight line.

[0011] Preferably, the first mounting plate is disposed inside the preheating box, the second mounting plate is disposed inside the furnace body, the connecting rod is disposed inside the connecting frame, and the furnace body is connected to the preheating box through the connecting frame.

[0012] Preferably, the outer wall of the preheating box is rotatably connected to a first door panel, the end of the furnace body is rotatably connected to a second door panel, and a placement groove is provided at the connection between the surface of the placement block and the wafer body.

[0013] Preferably, the outer wall of the second mounting plate is provided with a second electric push rod that is fixedly connected to the bottom of the lifting frame, the connection between the outer wall of the second mounting plate and the lifting frame is provided with a lifting groove, and the bottom of the lifting frame is fixedly connected with a telescopic rod that is fixedly connected to the outer wall of the second mounting plate.

[0014] Preferably, the outer wall of the lifting frame is provided with a third electric push rod. One end of the third electric push rod is fixedly connected to a sliding rod that is slidably connected to the outer wall of the lifting frame. The outer wall of the sliding rod is rotatably connected to a pull rod that is rotatably connected to the outer wall of the positioning rod. Through the coordinated use of the lifting frame, the pull rod, the positioning rod, and the positioning block, after the wafer is placed on the placement block, the third electric push rod can be opened to drive the sliding rod to slide along the outer wall of the lifting frame. Under the rotational connection of the pull rod, the positioning block fixedly connected to the positioning rod is driven to limit and fix the wafer on both sides, and the second electric push rod is driven to drive the lifting frame to slide along the inner wall of the lifting groove, so that the wafer is in a suspended positioning state, further improving the effect of all-round processing of the wafer surface.

[0015] Preferably, there are two sets of pull rods, and the positions of the two sets of pull rods are symmetrical about the central axis of the sliding rod. The pull rods and the positioning rods are arranged in a one-to-one correspondence. The contact part between the positioning block and the wafer body is tough.

[0016] Preferably, the outer wall of the heat storage tank is fixedly connected to a first gas supply pipe via a connecting pump. One end of the first gas supply pipe is fixedly connected to a rotary joint. A motor is installed inside the furnace body. The output end of the motor is fixedly connected to a jet pipe sleeved on the outer wall of the rotary joint. Through the coordinated use of the heat storage pipe, the first gas supply pipe, the heating pipe, and the jet pipe, heat can be purified and recovered from the furnace. The first gas supply pipe allows heat to be transported to the jet pipe, and the motor-driven jet pipe angle adjustment allows heat to diffuse to all parts of the wafer. At the same time, the ring-shaped heating pipe allows for all-around processing of the wafer, reducing blind spots in the wafer processing within the furnace.

[0017] Preferably, the jet pipes are provided in two sets, and the positions of the two sets of jet pipes are symmetrical about the central axis of the wafer body.

[0018] Preferably, the jet pipe is connected to the first air supply pipe via a rotary joint.

[0019] Compared with the prior art, the beneficial effects of this invention are as follows:

[0020] 1. This invention, through the arrangement of a first mounting plate, a second mounting plate, a suction hood, a heat storage tank, and a second air supply pipe, enables multiple batches of wafers to be fed onto the first and second mounting plates respectively. During normal processing in the furnace, the wafers on the second mounting plate absorb heat from the furnace through the suction hood. With the setting of an electrostatic dust removal box, the recovered heat is purified and then transported to the heat storage tank and the second air supply pipe to preheat the wafers in the preheating box. This prevents the wafers on the first mounting plate from being directly input into the furnace, which could result in a large temperature difference and affect the quality of wafer processing.

[0021] 2. By using the heat storage pipe, the first gas supply pipe, the heating pipe and the jet pipe in combination, the present invention can purify and recover the heat in the furnace. The first gas supply pipe allows the heat to be transported to the jet pipe. With the motor driving the jet pipe to adjust the angle, the heat can be diffused to all parts of the wafer. At the same time, with the heating pipe arranged in a ring shape, the wafer can be processed from all directions, reducing the possibility of blind spots in the wafer processing in the furnace.

[0022] 3. By using the lifting frame, pulling rod, positioning rod, and positioning block in combination, this invention enables the third electric push rod to be activated after the wafer is placed on the placement block. This drives the sliding rod to slide along the outer wall of the lifting frame, and under the rotational connection of the pulling rod, the positioning block, which is fixedly connected to the positioning rod, limits and fixes both sides of the wafer. The second electric push rod is then activated to drive the lifting frame to slide along the inner wall of the lifting groove, so that the wafer is in a suspended positioning state, further improving the effect of all-round surface treatment of the wafer. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the overall internal structure of the present invention;

[0025] Figure 3 This is a schematic diagram of the positional distribution of the heating tube and the wafer body in this invention;

[0026] Figure 4 This is a schematic diagram of the lifting frame position distribution structure of the present invention;

[0027] Figure 5 This is a schematic diagram of the positional distribution of the placement block and the lifting frame according to the present invention;

[0028] Figure 6 For the present invention Figure 4 Enlarged structural diagram at point A in the diagram;

[0029] Figure 7 For the present invention Figure 4 Enlarged structural diagram at point B in the diagram;

[0030] Figure 8 This is a schematic diagram of the air intake hood position distribution structure of the present invention;

[0031] Figure 9 This is a schematic diagram of the connection structure between the first mounting plate and the second mounting plate of the present invention.

[0032] The labels in the attached diagram are:

[0033] 1. Furnace body; 2. Preheating box; 3. First door panel; 4. Second door panel; 5. Connecting frame; 6. Heating tube; 7. First electric push rod; 8. First mounting plate; 9. Connecting rod; 10. Second mounting plate; 11. Placement block; 12. Wafer body; 13. Second electric push rod; 14. Lifting frame; 15. Lifting groove; 16. Telescopic rod; 17. Third electric push rod; 18. Sliding rod; 19. Pulling rod; 20. Positioning rod; 21. Positioning block; 22. Suction hood; 23. Electrostatic dust removal box; 24. Conveying pipe; 25. Heat storage tank; 26. First air supply pipe; 27. Rotary joint; 28. Jet pipe; 29. ​​Motor; 30. Second air supply pipe. Detailed Implementation

[0034] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0035] Example 1:

[0036] Please see Figures 1 to 9 This embodiment provides an annealing furnace for batch processing of semiconductor wafers, including a furnace body 1. A connecting frame 5 is fixedly connected to one end of the furnace body 1. A preheating box 2 is fixedly connected to one end of the connecting frame 5. Heating tubes 6 are arranged in a ring shape and distributed in a straight line inside the furnace body 1. A first electric push rod 7 is arranged at the end of the preheating box 2. A first mounting plate 8 is fixedly connected to one end of the first electric push rod 7. A connecting rod 9 is fixedly connected to the end of the first mounting plate 8. A second mounting plate 10 is fixedly connected to one end of the connecting rod 9. A placement block 11 is fixedly connected to the top of the second mounting plate 10. A wafer body 12 is placed on the surface of the placement block 11. The first mounting plate 8 is located inside the preheating box 2. The second mounting plate 10 is located inside the furnace body 1. The connecting rod 9 is located inside the connecting frame 5. The furnace body 1 is connected to the preheating box 2 through the connecting frame 5.

[0037] The outer wall of the second mounting plate 10 is slidably connected to a lifting frame 14, and the outer wall of the lifting frame 14 is slidably connected to a positioning rod 20. One end of the positioning rod 20 is fixedly connected to a positioning block 21 located on one side of the wafer body 12. The outer wall of the lifting frame 14 is provided with a third electric push rod 17. One end of the third electric push rod 17 is fixedly connected to a sliding rod 18 that is slidably connected to the outer wall of the lifting frame 14. The outer wall of the sliding rod 18 is rotatably connected to a pulling rod 19 that is rotatably connected to the outer wall of the positioning rod 20. There are two sets of pulling rods 19. The positions of the two sets of pulling rods 19 are symmetrical about the central axis of the sliding rod 18, and the pulling rods 19 and the positioning rods 20 are arranged in a one-to-one correspondence. The contact part between the positioning block 21 and the wafer body 12 is tough.

[0038] An air suction hood 22 is installed at the top of the inner cavity of the furnace body 1. The top of the air suction hood 22 is fixedly connected to an electrostatic dust removal box 23 located at the top of the furnace body 1 via a connecting pipe. The outer wall of the electrostatic dust removal box 23 is connected to a conveying pipe 24 via a connecting pump. One end of the conveying pipe 24 is fixedly connected to a heat storage tank 25 located on the outer wall of the furnace body 1. The outer wall of the heat storage tank 25 is fixedly connected to a second air supply pipe 30 fixedly connected to the top of the preheating box 2 via a connecting pump. After multiple batches of wafers are fed onto the first mounting plate 8 and the second mounting plate 10 respectively, when the wafers on the second mounting plate 10 are being processed normally in the furnace body 1, the heat inside the furnace is absorbed by the air suction hood 22. With the electrostatic dust removal box 23, the recovered heat is purified and then conveyed to the heat storage tank 25 and the second air supply pipe 30 to preheat the wafers in the preheating box 2. This prevents the wafers on the first mounting plate 8 from being directly input into the furnace, which would result in a large temperature difference and affect the quality of wafer processing.

[0039] like Figure 7 As shown, the outer wall of the preheating box 2 is rotatably connected to the first door plate 3, and the end of the furnace body 1 is rotatably connected to the second door plate 4. The surface of the placement block 11 and the connection part of the wafer body 12 are provided with a placement groove. Through the setting of the first door plate 3 and the second door plate 4, the wafers are respectively installed in the furnace and the preheating box 2.

[0040] like Figure 6 As shown, the outer wall of the second mounting plate 10 is provided with a second electric push rod 13 that is fixedly connected to the bottom of the lifting frame 14. The connection between the outer wall of the second mounting plate 10 and the lifting frame 14 is provided with a lifting groove 15. The bottom of the lifting frame 14 is fixedly connected with a telescopic rod 16 that is fixedly connected to the outer wall of the second mounting plate 10. The lifting frame 14 forms a lifting structure through the second electric push rod 13 and the lifting groove 15, so as to adjust the height of the wafer after clamping and fixing, and play the role of levitation processing of the wafer.

[0041] like Figure 6As shown, the outer wall of the heat storage tank 25 is fixedly connected to a first gas supply pipe 26 via a connecting pump. One end of the first gas supply pipe 26 is fixedly connected to a rotary joint 27. A motor 29 is installed inside the furnace body 1. The output end of the motor 29 is fixedly connected to a jet pipe 28 sleeved on the outer wall of the rotary joint 27. There are two sets of jet pipes 28, and the positions of the two sets of jet pipes 28 are symmetrical about the central axis of the wafer body 12. The jet pipes 28 are connected to the first gas supply pipe 26 via the rotary joint 27. When purifying and recovering heat in the furnace, the first gas supply pipe 26 allows heat to be transported into the jet pipes 28. With the motor 29 driving the jet pipes 28 to adjust the angle, the heat is diffused to all parts of the wafer. At the same time, with the heating tube 6 arranged in a ring shape, the wafer is processed from all directions, reducing the possibility of blind spots in the wafer processing in the furnace.

[0042] Working principle:

[0043] like Figure 1-9 As shown, when the semiconductor wafer batch processing annealing furnace is in use, the first door plate 3 and the second door plate 4 are opened, so that the wafers to be processed are fed onto the top of the first mounting plate 8 and the second mounting plate 10 respectively, so that the first mounting plate 8 and the second mounting plate 10 are in the furnace and the preheating box 2 respectively.

[0044] The heating tube 6 inside the furnace is opened to allow the wafer to undergo annealing in the furnace. The suction hood 22 is opened to absorb the heat inside the furnace. With the electrostatic dust removal box 23 in place, the recovered heat is purified and then transported to the heat storage tank 25 and the second air supply pipe 30 to preheat the wafer in the preheating box 2.

[0045] After the wafers on the second mounting plate 10 are processed, the second door plate 4 is opened and the first electric push rod 7 is driven to move the first mounting plate 8 and the connecting rod 9 to the second mounting plate 10 in a telescopic motion, so that the second mounting plate 10 extends from the second door plate 4 and the wafers on the second mounting plate 10 are unloaded. At this time, the wafers on the first mounting plate 8 move into the furnace for processing. After the wafers on the first mounting plate 8 are processed, the first electric push rod 7 is retracted, so that the second mounting plate 10 after replenishment moves into the furnace. The processed wafers on the first mounting plate 8 move into the preheating box 2, and the first door plate 3 is opened to unload the wafers on the first mounting plate 8. This process is repeated to process batches of wafers alternately in the furnace.

[0046] When the wafer moves into the furnace for processing, the heat inside the furnace is purified and recovered for reuse. With the first gas supply pipe 26 set up, the heat is transported to the jet pipe 28. With the motor 29 driving the jet pipe 28 and adjusting the angle, the heat is diffused to all parts of the wafer. At the same time, with the heating pipe 6 set in a ring shape, the wafer is processed from all directions, reducing the possibility of blind spots in the wafer processing inside the furnace.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An annealing furnace for batch processing of semiconductor wafers, comprising a furnace body (1), characterized in that: A connecting frame (5) is fixedly connected to the end of the furnace body (1), and a preheating box (2) is fixedly connected to one end of the connecting frame (5). A heating tube (6) is provided inside the furnace body (1). A first electric push rod (7) is provided at the end of the preheating box (2). A first mounting plate (8) is fixedly connected to one end of the first electric push rod (7). A connecting rod (9) is fixedly connected to the end of the first mounting plate (8). A second mounting plate (10) is fixedly connected to one end of the connecting rod (9). A placement block (11) is fixedly connected to the top of the second mounting plate (10). A wafer body (12) is placed on the surface of the placement block (11). The outer wall of the second mounting plate (10) is slidably connected to a lifting frame (14), and the outer wall of the lifting frame (14) is slidably connected to a positioning rod (20). One end of the positioning rod (20) is fixedly connected to a positioning block (21) located on one side of the wafer body (12). The top of the inner cavity of the furnace body (1) is provided with an air suction hood (22). The top of the air suction hood (22) is fixedly connected to an electrostatic dust removal box (23) located on the top of the furnace body (1) via a connecting pipe. The outer wall of the electrostatic dust removal box (23) is provided with a conveying pipe (24) connected to a pump. One end of the conveying pipe (24) is fixedly connected to a heat storage tank (25) located on the outer wall of the furnace body (1). The outer wall of the heat storage tank (25) is fixedly connected to a second air supply pipe (30) fixedly connected to the top of the preheating box (2) via a connecting pump.

2. The annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The heating tubes (6) are arranged in a ring shape and are distributed in a straight line.

3. The annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The first mounting plate (8) is located inside the preheating box (2), the second mounting plate (10) is located inside the furnace body (1), the connecting rod (9) is located inside the connecting frame (5), and the furnace body (1) is connected to the preheating box (2) through the connecting frame (5).

4. An annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The preheating box (2) is rotatably connected to the outer wall of the first door panel (3), and the furnace body (1) is rotatably connected to the end of the second door panel (4). The surface of the placement block (11) and the connection part between it and the wafer body (12) are provided with a placement groove.

5. An annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The outer wall of the second mounting plate (10) is provided with a second electric push rod (13) that is fixedly connected to the bottom of the lifting frame (14). The connection between the outer wall of the second mounting plate (10) and the lifting frame (14) is provided with a lifting groove (15). The bottom of the lifting frame (14) is fixedly connected with a telescopic rod (16) that is fixedly connected to the outer wall of the second mounting plate (10).

6. An annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The outer wall of the lifting frame (14) is provided with a third electric push rod (17), one end of the third electric push rod (17) is fixedly connected to a sliding rod (18) that is slidably connected to the outer wall of the lifting frame (14), and the outer wall of the sliding rod (18) is rotatably connected to a pulling rod (19) that is rotatably connected to the outer wall of the positioning rod (20).

7. An annealing furnace for batch processing of semiconductor wafers according to claim 6, characterized in that: The pull rod (19) is provided in two sets. The positions of the two sets of pull rods (19) are symmetrical about the central axis of the sliding rod (18), and the pull rod (19) and the positioning rod (20) are provided in a one-to-one correspondence. The contact part between the positioning block (21) and the wafer body (12) is tough.

8. An annealing furnace for batch processing of semiconductor wafers according to claim 1, characterized in that: The outer wall of the heat storage tank (25) is fixedly connected to a first gas supply pipe (26) via a connecting pump. One end of the first gas supply pipe (26) is fixedly connected to a rotary joint (27). The furnace body (1) is equipped with a motor (29). The output end of the motor (29) is fixedly connected to a jet pipe (28) sleeved on the outer wall of the rotary joint (27).

9. An annealing furnace for batch processing of semiconductor wafers according to claim 8, characterized in that: The jet pipes (28) are provided in two sets, and the positions of the two sets of jet pipes (28) are symmetrical about the central axis of the wafer body (12).

10. An annealing furnace for batch processing of semiconductor wafers according to claim 8, characterized in that: The jet pipe (28) is connected to the first air supply pipe (26) via a rotary joint (27).

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