Nitrogen sealing system for vacuum vertical furnace tube

Abstract

The utility model discloses a nitrogen sealing system for a vacuum vertical furnace tube. The nitrogen sealing system comprises a vacuum cavity, a wafer boat, a heater, a reaction furnace tube, a connecting manifold, a vacuum pump, a first nitrogen sealing device, a second nitrogen sealing device, a third nitrogen sealing device, a wafer boat lifter and a vacuum pipeline, the connecting manifold is mounted above the vacuum cavity; the reaction furnace tube is mounted above the connecting manifold; the wafer boat is fixed on the wafer boat lifter, and the wafer boat lifter drives the wafer boat to move up and down; the vacuum pipeline is installed on the side of the connecting manifold. The end, away from the connecting manifold, of the vacuum pipeline is connected with the vacuum pump. The first nitrogen sealing device is arranged between the vacuum pipeline and the vacuum pump for sealing; the second nitrogen sealing device is arranged between the reaction furnace tube and the connecting manifold for sealing; and the third nitrogen sealing device is arranged between the vacuum cavity and the connecting manifold for sealing, so that the oxygen leakage rate is reduced, the equipment maintenance cost is reduced, and the process stability is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a gas sealing system field especially a nitrogen gas sealing system for vacuum vertical furnace tube. BACKGROUND

[0002] In the field of semiconductor manufacturing, atomic layer deposition (ALD) is an important thin film preparation technology, widely used in the manufacture of high-precision electronic devices. ALD process is very sensitive to oxygen content, the presence of oxygen may affect the growth quality and performance of the film. Therefore, it is crucial to maintain low oxygen content in the reaction chamber of the ALD equipment. Currently, the reaction chamber is mainly sealed by a sealing ring, however, a small amount of oxygen may still leak into the reaction chamber through the sealing ring, thereby affecting the ALD process.

[0003] Prior art solution: The existing solution is mainly to flush the reaction chamber with high-purity nitrogen gas to minimize the impact of oxygen. In addition, some equipment manufacturers will add multiple sealing rings between the reaction chamber and the external environment to reduce the possibility of oxygen leakage. However, these methods cannot completely eliminate the risk of oxygen leakage, especially under long-term operation and high-temperature conditions, the sealing ring may age or be damaged, resulting in an increase in oxygen leakage.

[0004] Prior art problems: Although the existing solution can reduce the amount of oxygen leakage to some extent, there are still some problems. First, the supply and maintenance cost of high-purity nitrogen gas is high, which increases the economic burden of equipment operation. Second, the design of multiple sealing rings can reduce oxygen leakage, but also increases the complexity and maintenance difficulty of the equipment. In addition, under high-temperature conditions, the aging rate of the sealing ring will accelerate, resulting in a decline in sealing effect, which requires frequent replacement of the sealing ring, increasing the maintenance cost and downtime of the equipment. Therefore, how to further reduce the amount of oxygen leakage while reducing the maintenance cost and operating burden of the equipment is a problem that needs to be solved in this field. Utility model content

[0005] The purpose of the utility model is to provide a nitrogen gas sealing system for vacuum vertical furnace tube to solve the problems raised in the above background.

[0006] The above technical purpose of the utility model is realized by the following technical scheme:

[0007] A nitrogen gas sealing system for vacuum vertical furnace tube, comprising a vacuum cavity, a wafer boat, a heater, a reaction furnace tube, a connection manifold, a vacuum pump, a first nitrogen gas sealing device, a second nitrogen gas sealing device, a third nitrogen gas sealing device, a wafer boat elevator, and a vacuum pipeline.

[0008] The connection manifold is installed above the vacuum cavity.

[0009] The reaction furnace tube is installed above the connection manifold;

[0010] The crystal boat is fixed on the crystal boat elevator, and the crystal boat elevator drives the crystal boat to move up and down;

[0011] The vacuum pipeline is installed on the side of the connection manifold, and the end of the vacuum pipeline away from the connection manifold is connected with the vacuum pump;

[0012] The first nitrogen sealing device is arranged between the vacuum pipeline and the vacuum pump for sealing;

[0013] The second nitrogen sealing device is arranged between the reaction furnace tube and the connection manifold for sealing;

[0014] The third nitrogen sealing device is arranged between the vacuum cavity and the connection manifold for sealing.

[0015] As a preferred, the first nitrogen sealing device comprises a first sealing ring, a first nitrogen cavity and a first nitrogen pipeline, the first sealing ring is arranged between the vacuum pipeline and the vacuum pump, and the first nitrogen cavity and the first nitrogen pipeline are arranged on the vacuum pipeline.

[0016] As a preferred, the second nitrogen sealing device comprises a second sealing ring, a second nitrogen cavity, a second nitrogen pipeline and a reaction furnace tube mounting flange, the second sealing ring is arranged between the reaction furnace tube and the connection manifold, the second nitrogen cavity and the second nitrogen pipeline are arranged on the reaction furnace tube mounting flange, and the reaction furnace tube mounting flange is used for pressing the reaction furnace tube above the connection manifold for sealing.

[0017] As a preferred, the third nitrogen sealing device comprises a third sealing ring, a third nitrogen pipeline, a fourth sealing ring, a reaction gas inlet pipeline and a reaction gas inlet pipeline interface, the third sealing ring is arranged between the vacuum cavity and the connection manifold, the fourth sealing ring is arranged between the reaction gas inlet pipeline and the reaction gas inlet pipeline interface, the third nitrogen pipeline is installed above the vacuum cavity, and the third nitrogen pipeline is arranged on the side of the third sealing ring.

[0018] As a preferred, the third nitrogen pipeline is in a ring structure, a nitrogen ring pipeline upper gas outlet hole is arranged at the top of the third nitrogen pipeline, a nitrogen ring pipeline inner side gas outlet hole is arranged at the inner side of the third nitrogen pipeline, and a nitrogen ring pipeline gas inlet is arranged at the top of the third nitrogen pipeline, the nitrogen ring pipeline upper gas outlet hole is arranged to direct the gas outlet direction to the fourth sealing ring, and the nitrogen ring pipeline inner side gas outlet hole is arranged to direct the gas outlet direction to the third sealing ring.

[0019] As a preferred, the nitrogen ring pipeline gas inlet is provided with three, and each nitrogen ring pipeline gas inlet is uniformly distributed on the third nitrogen pipeline.

[0020] Beneficial effects: 1. Reduce oxygen leakage: The nitrogen sealing system of the present application can effectively prevent trace oxygen from entering the reaction cavity from the sealing ring by filling nitrogen at the location of minor leakage, thereby further reducing the amount of oxygen leakage. Compared with the prior art, this design can effectively reduce the risk of oxygen leakage in a wider range of application scenarios, especially in high temperature or long time operation conditions, by actively filling nitrogen. 2. Reduce equipment maintenance cost: The nitrogen sealing system of the present application adopts a single sealing ring design, which reduces the complexity and maintenance difficulty of the equipment compared with the multi-sealing ring design of the prior art, and also reduces the maintenance cost and downtime caused by frequent replacement of sealing rings. This design makes the equipment run more stably and is easier to maintain, thereby reducing the overall operating cost. 3. Improve process stability: The nitrogen sealing system of the present application can accurately control the oxygen content in the reaction cavity by accurately controlling the flow and pressure of nitrogen, thereby improving the stability of the ALD process. This design makes the growth quality and performance of the thin film more stable, thereby improving the manufacturing quality of electronic devices. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic diagram of the whole equipment of a nitrogen sealing system for a vacuum vertical furnace tube according to an embodiment of the present application;

[0022] Figure 2 is a schematic diagram of the whole structure according to an embodiment of the present application;

[0023] Figure 3 is a schematic diagram of the first nitrogen sealing device in Figure 2

[0024] is a schematic diagram of the second nitrogen sealing device in Figure 4 Figure 2 is a schematic diagram of the third nitrogen sealing device in

[0025] Figure 5 Figure 2

[0026] Figure 6 Figure 5

[0027] ​​​​​Reference: 1, vacuum cavity; 2, wafer boat; 3, heater; 4, reaction furnace tube; 5, connecting manifold; 6, vacuum pump; 7, first nitrogen sealing device; 701, first sealing ring; 702, first nitrogen cavity; 703, first nitrogen tube; 8, second nitrogen sealing device; 801, second sealing ring; 802, second nitrogen cavity; 803, second nitrogen tube; 804, reaction furnace tube mounting flange; 9, third nitrogen sealing device; 901, third sealing ring; 902, third nitrogen tube; 902a, nitrogen ring tube upper gas outlet hole; 902b, nitrogen ring tube inner side gas outlet hole; 902c, nitrogen ring tube gas inlet; 903, fourth sealing ring; 904, reaction gas inlet tube; 905, reaction gas inlet tube interface; 10, wafer boat elevator; 11, vacuum pipeline. DETAILED DESCRIPTION

[0028] The present disclosure is a nitrogen sealing system for a vacuum vertical furnace tube, referring to Figure 1 , the vacuum vertical furnace tube device involves the part of nitrogen sealing, including vacuum cavity 1, wafer boat 2, heater 3, reaction furnace tube 4.

[0029] Referring to Figure 2 , the overall structure diagram of the present disclosure includes connecting manifold 5, vacuum pump 6, first nitrogen sealing device 7, second nitrogen sealing device 8, third nitrogen sealing device 9, wafer boat elevator 10, vacuum pipeline 11.

[0030] The connecting manifold 5 is installed above the vacuum cavity 1, used to connect other components;

[0031] The reaction furnace tube 4 is installed above the connecting manifold 5;

[0032] The wafer boat 2 is fixed on the wafer boat elevator 10, and the wafer boat elevator 10 drives the wafer boat 2 to move up and down;

[0033] The vacuum pipeline 11 is installed on the side of the connecting manifold 5, and the other end is connected with the vacuum pump 6;

[0034] The first nitrogen sealing device 7 is arranged between the vacuum pipeline 11 and the vacuum pump 6 for sealing;

[0035] The second nitrogen sealing device 8 is arranged between the reaction furnace tube 4 and the connecting manifold 5 for sealing;

[0036] The third nitrogen sealing device 9 is arranged between the vacuum cavity 1 and the connecting manifold 5 for sealing;

[0037] Referring to Figure 3 , the first nitrogen sealing device 7 is a schematic diagram, including first sealing ring 701, first nitrogen cavity 702, first nitrogen tube 703;

[0038] The first sealing ring 701 is arranged between the vacuum pipeline 11 and the vacuum pump 6.

[0039] The first nitrogen cavity 702 and the first nitrogen pipeline 703 are arranged on the vacuum pipeline 11.

[0040] Referring to Figure 4 The second nitrogen sealing device 8 is shown in the figure, which comprises a second sealing ring 801, a second nitrogen cavity 802, a second nitrogen pipeline 803 and a reaction furnace tube mounting flange 804.

[0041] The second sealing ring 801 is arranged between the reaction furnace tube 4 and the connecting manifold 5.

[0042] The second nitrogen cavity 802 and the second nitrogen pipeline 803 are arranged on the reaction furnace tube mounting flange 804.

[0043] The reaction furnace tube mounting flange 804 presses the reaction furnace tube 4 above the connecting manifold 5 to seal.

[0044] Referring to Figure 5 The third nitrogen sealing device 9 is shown in the figure, which comprises a third sealing ring 901, a third nitrogen pipeline 902, a fourth sealing ring 903, a reaction gas inlet pipeline 904 and a reaction gas inlet pipeline interface 905.

[0045] The third sealing ring 901 is arranged between the vacuum cavity 1 and the connecting manifold 5.

[0046] The fourth sealing ring 903 is arranged between the reaction gas inlet pipeline 904 and the reaction gas inlet pipeline interface 905.

[0047] The third nitrogen pipeline 902 is arranged above the vacuum cavity 1 and on the side of the third sealing ring 901. Figure 6 The third nitrogen pipeline 902 is shown in the figure, the top of the third nitrogen pipeline 902 is provided with a nitrogen ring pipeline upper gas outlet hole 902a, the inner side of the third nitrogen pipeline 902 is provided with a nitrogen ring pipeline inner side gas outlet hole 902b, the top of the third nitrogen pipeline 902 is further provided with a nitrogen ring pipeline gas inlet port 902c, and the third nitrogen pipeline 902 has a ring structure.

[0048] The nitrogen ring pipeline upper gas outlet hole 902a is arranged to direct the gas outlet direction to the fourth sealing ring 903.

[0049] The nitrogen ring pipeline inner side gas outlet hole 902b is arranged to direct the gas outlet direction to the third sealing ring 901.

[0050] The nitrogen ring pipeline gas inlet port 902c is provided with three, and each nitrogen ring pipeline gas inlet port 902c is uniformly distributed on the third nitrogen pipeline 902.

[0051] Working principle:

[0052] Before the process starts, the furnace tube equipment is assembled, and after each component is assembled, the nitrogen pipeline is connected, and nitrogen is filled at each nitrogen sealing device.

[0053] During the process, the wafer boat elevator 10 drives the wafer boat 2 to move upwards and abut against the vacuum cavity 1, the vacuum pump 6 starts to pump, and after reaching the specified pressure, the reaction gas is sequentially introduced from the reaction gas inlet pipe 904 to perform the process step. During this period, the first nitrogen sealing system 7 and the second nitrogen sealing system 8 are filled with nitrogen to maintain a certain pressure, isolate air, ensure sealing, and the third nitrogen sealing system 9 continuously fills nitrogen and controls the flow, and the third nitrogen pipe 902 continuously sprays nitrogen to form a nitrogen atmosphere around the third sealing ring 901 and the fourth sealing ring 903, preventing oxygen in the air from leaking into the reaction cavity.

[0054] After the process is completed, the wafer boat elevator 10 drives the wafer boat 2 to move downwards, stops the nitrogen supply, and releases the pressure of the first nitrogen sealing system 7 and the second nitrogen sealing system 8.

[0055] In the above process, an automatic nitrogen sealing system is formed through three nitrogen sealing devices and related control systems, which realizes further sealing protection of each sealing surface of the reaction cavity and prevents the leakage of a small amount of oxygen that cannot be monitored by the monitor.

Claims

1. A nitrogen sealing system for a vacuum vertical furnace tube, characterized in that: It comprises a vacuum chamber (1), a crystal boat (2), a heater (3), a reaction furnace tube (4), a connecting manifold (5), a vacuum pump (6), a first nitrogen sealing device (7), a second nitrogen sealing device (8), a third nitrogen sealing device (9), a crystal boat (2) elevator, and a vacuum pipeline (11); The connecting manifold (5) is installed above the vacuum chamber (1); The reaction furnace tube (4) is installed above the connecting manifold (5); The crystal boat (2) is fixed on a crystal boat (2) elevator, and the crystal boat (2) elevator drives the crystal boat (2) to move up and down; The vacuum pipe (11) is installed on the side of the connecting manifold (5), and one end of the vacuum pipe (11) away from the connecting manifold (5) is connected to the vacuum pump (6); The first nitrogen sealing device (7) is provided between the vacuum pipeline (11) and the vacuum pump (6) for sealing; The second nitrogen sealing device (8) is provided between the reaction furnace tube (4) and the connecting manifold (5) for sealing; The third nitrogen sealing device (9) is provided between the vacuum chamber (1) and the connecting manifold (5) for sealing.

2. A nitrogen sealing system for a vacuum vertical furnace tube according to claim 1, characterized in that: The first nitrogen sealing device (7) comprises a first sealing ring (701), a first nitrogen chamber (702) and a first nitrogen pipe (703); the first sealing ring (701) is placed between the vacuum pipeline (11) and the vacuum pump (6); and the first nitrogen chamber (702) and the first nitrogen pipe (703) are arranged on the vacuum pipeline (11).

3. A nitrogen sealing system for a vacuum vertical furnace tube according to claim 1, characterized in that: The second nitrogen sealing device (8) comprises a second sealing ring (801), a second nitrogen chamber (802), a second nitrogen pipe (803) and a reaction furnace tube mounting flange (804); the second sealing ring (801) is placed between the reaction furnace tube (4) and the connecting manifold (5); the second nitrogen chamber (802) and the second nitrogen pipe (803) are arranged on the reaction furnace tube mounting flange (804); and the reaction furnace tube mounting flange (804) is used to press the reaction furnace tube (4) onto the connecting manifold (5) for sealing.

4. A nitrogen sealing system for a vacuum vertical furnace tube according to claim 1, characterized in that: The third nitrogen sealing device (9) comprises a third sealing ring (901), a third nitrogen pipe (902), a fourth sealing ring (903), a reaction gas inlet pipe (904), and a reaction gas inlet pipe (904) interface; the third sealing ring (901) is arranged between the vacuum chamber (1) and the connecting manifold (5); the fourth sealing ring (903) is arranged between the reaction gas inlet pipe (904) and the reaction gas inlet pipe (904) interface; the third nitrogen pipe (902) is installed above the vacuum chamber (1); and the third nitrogen pipe (902) is arranged on the side of the third sealing ring (901).

5. A nitrogen sealing system for a vacuum vertical furnace tube according to claim 4, characterized in that: The third nitrogen tube (902) is an annular structure. A nitrogen ring tube upper air outlet (902a) is provided on the top of the third nitrogen tube (902). A nitrogen ring tube inner air outlet (902b) is provided on the inner side of the third nitrogen tube (902). A nitrogen ring tube air inlet (902c) is also provided on the top of the third nitrogen tube (902). The air outlet direction of the nitrogen ring tube upper air outlet (902a) points to the fourth sealing ring (903), and the air outlet direction of the nitrogen ring tube inner air outlet (902b) points to the third sealing ring (901).

6. A nitrogen sealing system for a vacuum vertical furnace tube according to claim 5, characterized in that: There are three nitrogen ring pipe air inlets (902c) in total, and each of the nitrogen ring pipe air inlets (902c) is evenly distributed on the third nitrogen pipe (902).

Images