Tail gas separation device of tubular reaction furnace

Abstract

The utility model belongs to the technical field of semiconductor processing, and discloses a tubular reaction furnace tail gas separation device which comprises a separation tube assembly and a heating assembly, the separation tube assembly comprises a separation tube and activated carbon filled in the separation tube, the activated carbon is used for adsorbing silane gas in tail gas, and the heating assembly is used for heating the activated carbon to desorb the silane gas. A gas inlet of the separation pipe is communicated with the tubular reaction furnace, a gas outlet of the separation pipe can be selectively communicated with combustion tower equipment or gas recovery equipment, the separation pipe assembly has an adsorption separation state and a heating desorption state, and when the separation pipe assembly is in the adsorption separation state, the gas outlet is communicated with the gas recovery equipment; when the separation pipe assembly is in a heating desorption state, the gas outlet is communicated with the combustion tower equipment. According to the tail gas separation device of the tubular reaction furnace, silane gas in tail gas can be separated, the silane gas is combusted to reduce pollution, and the phenomena that the process cost is increased and the working efficiency of the reaction furnace is reduced due to dust accumulation in the washing tower are prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor processing, in particular to a tail gas separation device for a tubular reactor. Background Art

[0002] Tubular plasma enhanced chemical vapor deposition (PECVD) equipment is widely used in the thin film preparation process of anti-reflection film, passivation layer, tunneling oxide layer and other thin films of solar cells. In the PECVD process, silane is often used as an active gas to participate in the film-making reaction. Silane is a colorless, pungent gas with a high toxicity and flammability. It can cause irritation and damage to the human respiratory system, eyes, skin, etc. Long-term contact may also cause serious diseases such as lung cancer. At the same time, silane gas can also react with oxygen in the air and explode when encountering a fire source. Therefore, the silane left over from the reaction needs to be treated to avoid direct discharge into the atmosphere to cause harm and pollution. The commonly used silane treatment method is the combustion method, which burns the silane gas into harmless substances through a combustion tower.

[0003] However, in addition to silane, the tail gas left over from the PECVD process also contains special gases such as phosphine and hydrogen. These special gases are prone to safety issues and cannot be handled by a combustion tower. The above-mentioned special gases such as phosphine and hydrogen can be handled by a scrubber, but the scrubber will generate a lot of dust in the process of handling silane gas, which requires regular maintenance. The single maintenance time of the scrubber equipment takes about two hours, and the single maintenance cost is several thousand yuan, which greatly increases the process cost. Moreover, it will also affect the service life of the scrubber and the working efficiency of the PECVD equipment. Utility Model Content

[0004] The utility model aims to provide a tubular reactor tail gas separation device, which is used to solve the problems that the existing reactor tail gas is not separated, the combustion tower cannot process special gases such as phosphine and hydrogen in the tail gas, and the safety is poor, and the washing tower is prone to produce a large amount of dust due to silane gas when processing the tail gas, thereby increasing the process cost and affecting the service life of the washing tower and the working efficiency of the PECVD equipment.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A tubular reactor tail gas separation device is provided for separating the tail gas of the tubular reactor. The tubular reactor tail gas separation device comprises a separation tube assembly and a heating assembly. The separation tube assembly comprises a separation tube and activated carbon filled in the separation tube. The activated carbon is used to adsorb silane gas in the tail gas. The heating assembly is used to heat the activated carbon to desorb the silane gas. The air inlet of the separation tube is connected to the tubular reactor. The air outlet of the separation tube can be selectively connected to a combustion tower device or a gas recovery device. The separation tube assembly has an adsorption separation state and a heating desorption state. When the separation tube assembly is in the adsorption separation state, the air outlet is connected to the gas recovery device. When the separation tube assembly is in the heating desorption state, the air outlet is connected to the combustion tower device.

[0007] In one embodiment, the heating assembly includes a heating wire, and the heating wire is wound around the outside of the separation tube.

[0008] In one embodiment, the heating assembly further comprises an insulating protection tube, wherein the insulating protection tube is sleeved on the outer side of the heating wire; and / or,

[0009] The heating wire extends along the axial direction of the separation tube and is bent and rotated multiple times to form an S-shape to surround the outer circumference of the separation tube; and / or,

[0010] The heating component also includes a supporting ceramic ring, which is sleeved on the outer circumference of the separation tube, and the heating metal wire is passed through the supporting ceramic ring.

[0011] In one of the embodiments, the tail gas separation device of the tubular reactor further includes an outer protective shell, and the outer protective shell is sleeved on the outer side of the insulating protection tube.

[0012] In one of the embodiments, a cooling cavity is provided in the outer protective shell, and a water inlet and a water outlet connected to the cooling cavity are provided on the outer protective shell, and the water inlet and the water outlet are connected to an external cooling device.

[0013] In one embodiment, the tubular reactor tail gas separation device also includes a connecting flange, which is used to connect the combustion tower equipment and the gas recovery equipment. The separation tube assembly is provided with an outlet flange, and the connecting flange is detachably connected to the outlet flange.

[0014] In one embodiment, the heating component further includes a circuit and an electrode flange tube, the connecting flange is provided with a guide port, the electrode flange tube is arranged on the connecting flange and connected to the guide port, and the electrode flange tube is used to guide the circuit.

[0015] In one embodiment, the tubular reactor tail gas separation device also includes a three-way valve, a first interface of the three-way valve is connected to the separation tube, a second interface of the three-way valve is connected to the combustion tower equipment, and a third interface of the three-way valve is connected to the gas recovery equipment. When the separation tube assembly is in the adsorption separation state, the first interface is connected to the third interface, and when the separation tube assembly is in the heating desorption state, the first interface is connected to the second interface.

[0016] In one embodiment, the tail gas separation device of the tubular reactor further comprises a gas detection component, the gas detection component is arranged at the gas outlet, the gas detection component is used to detect the silane gas, and the gas detection component is communicatively connected to the heating component; and / or,

[0017] The tail gas separation device of the tubular reactor further comprises a temperature detection component, and the temperature detection component is used to detect the heating temperature of the heating component.

[0018] In one of the embodiments, the separation tube assembly further comprises at least one flow equalizer plate, which is disposed at the air inlet and / or the air outlet and / or in the separation tube, and has a plurality of flow equalizer holes.

[0019] Beneficial effects of the utility model:

[0020] The utility model provides a tubular reactor tail gas separation device, which includes a separation tube assembly and a heating assembly. The separation tube assembly includes a separation tube and activated carbon filled in the separation tube, and the activated carbon is used to adsorb silane gas in the tail gas. The air inlet of the separation tube is connected to the tubular reactor. When the tail gas generated by the tubular reactor enters the separation tube through the air inlet, the activated carbon can adsorb the silane gas in the tail gas, but will not adsorb gases such as phosphine and hydrogen. When the adsorption of silane gas by the activated carbon reaches a saturated state, the heating assembly is used to heat the activated carbon to desorb the silane gas. The gas outlet of the separation tube can be selectively connected to a combustion tower device or a gas recovery device. The separation tube assembly has an adsorption separation state and a heating desorption state. When the separation tube assembly is in the adsorption separation state, the gas outlet is connected to a gas recovery device that can process gases such as phosphine and hydrogen. The gas recovery device includes but is not limited to a washing tower. The tail gas after separation of silane gas can be completely processed by the scrubber, preventing dust accumulation inside the scrubber, ensuring the continuous operation of the scrubber, reducing the number of downtime maintenance of the scrubber, and avoiding the maintenance cost and damage cost of the scrubber from affecting the process cost and the working efficiency of the tubular reactor. When the separation tube assembly is in the heating and desorption state, the gas outlet is connected to the combustion tower equipment, and the desorbed silane gas enters the combustion tower through the gas outlet and is burned and processed, avoiding direct discharge to cause harm and pollution. The adsorption and heating desorption of activated carbon are both physical reactions, and no toxic or harmful additional substances will be produced. The reliability and safety of the tail gas separation device of the tubular reactor are good. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a tail gas separation device for a tubular reactor provided in an embodiment of the utility model;

[0022] Figure 2 It is a structural cross-sectional view of a tail gas separation device for a tubular reactor provided in an embodiment of the utility model;

[0023] Figure 3 It is a schematic diagram of the structural disassembly of a tail gas separation device for a tubular reactor provided in an embodiment of the utility model.

[0024] In the figure:

[0025] 1. Separation tube assembly; 11. Separation tube; 111. Air inlet; 112. Air outlet; 12. Activated carbon; 13. Outlet flange; 14. Flow equalizer plate; 141. Flow equalizer hole;

[0026] 2. Heating assembly; 21. Heating wire; 22. Insulation protection tube; 23. Supporting ceramic ring; 24. Electrode flange tube;

[0027] 3. Outer protective shell; 31. Cooling chamber; 32. Water inlet; 33. Water outlet;

[0028] 4. Connecting flange; 41. Guide port. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0030] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0032] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0033] like Figures 1 to 3 As shown, this embodiment provides a tubular reactor tail gas separation device, which is used to separate the tail gas of the tubular reactor. The tail gas is a mixed gas, including but not limited to silane gas, phosphine, hydrogen and the like.

[0034] The tail gas separation device of the tubular reactor includes a separation tube assembly 1 and a heating assembly 2. The separation tube assembly 1 includes a separation tube 11 and an activated carbon 12 filled in the separation tube 11. The activated carbon 12 is used to adsorb silane gas in the tail gas. The air inlet 111 of the separation tube 11 is connected to the tubular reactor. When the tail gas generated by the tubular reactor enters the separation tube 11 through the air inlet 111, the activated carbon 12 can adsorb the silane gas in the tail gas, but will not adsorb gases such as phosphine and hydrogen. When the adsorption of silane gas by the activated carbon 12 reaches a saturated state, the heating assembly 2 is used to heat the activated carbon 12 to desorb the silane gas. The gas outlet 112 of the separation tube 11 can be selectively connected to a combustion tower device or a gas recovery device. The separation tube assembly 1 has an adsorption separation state and a heating desorption state. When the separation tube assembly 1 is in the adsorption separation state, the gas outlet 112 is connected to the gas recovery device. The gas recovery device includes but is not limited to a washing tower that can process gases such as phosphine and hydrogen. The tail gas after separation of silane gas can be completely processed by the scrubber, which prevents dust accumulation inside the scrubber, ensures the continuous operation of the scrubber, reduces the number of downtime maintenance of the scrubber, avoids the maintenance cost and damage cost of the scrubber affecting the process cost, and affects the working efficiency of the tubular reactor. When the separation tube assembly 1 is in the heating and desorption state, the gas outlet 112 is connected to the combustion tower equipment, and the desorbed silane gas enters the combustion tower through the gas outlet 112 and is burned, avoiding direct discharge to cause harm and pollution. The adsorption and heating desorption of the activated carbon 12 are both physical reactions, and no toxic or harmful additional substances will be produced. The reliability and safety of the tail gas separation device of the tubular reactor are both good.

[0035] Regarding the heating method of the heating component 2, in one embodiment, the heating component 2 includes a heating wire 21, and the heating wire 21 is wound around the outside of the separation tube 11. The heating wire 21 generates heat when it is energized, thereby heating the activated carbon 12 outside the separation tube 11. The heating wire 21 can be a tantalum wire, which has the advantages of high melting point, good cold processing performance, high chemical stability, etc., is easy to bend into a required winding shape, and does not chemically react with the exhaust gas.

[0036] The heating wire 21 extends along the axial direction of the separation tube 11 and is bent and rotated multiple times into an S shape to surround the outer circumference of the separation tube 11. In this way, the heating wire 21 fully surrounds the outer circumference of the separation tube 11 in the circumferential and longitudinal directions, and the activated carbon 12 in the separation tube 11 is heated more evenly.

[0037] In order to support the heating wire 21, the heating assembly 2 further includes a supporting ceramic ring 23, which is sleeved on the outer circumference of the separation tube 11, and the heating wire 21 is passed through the supporting ceramic ring 23. Figure 3As shown, two supporting ceramic rings 23 are provided, which are respectively located at the two ends of the separation tube 11 , so that the heating wire 21 is stably supported in the length direction to ensure the relative installation position between the heating wire 21 and the separation tube 11 .

[0038] Of course, the number of the supporting ceramic rings 23 may be more than two, and a supporting ceramic ring 23 is also provided in the middle of the separation tube 11 to further increase the support for the heating wire 21 .

[0039] In one embodiment, the heating assembly 2 further includes an insulating protection tube 22, which is sleeved on the outside of the heating wire 21. The insulating protection tube 22 is made of ceramic material, and the insulating protection tube 22 covers the heating wire 21 to prevent the heating wire 21 from contacting other structural parts to form a short circuit, and can also keep the heating wire 21 warm to reduce heat loss.

[0040] In order to protect the insulating protection tube 22, the tubular reactor tail gas separation device also includes an outer protective shell 3, which is sleeved on the outside of the insulating protection tube 22 to prevent operators from directly contacting the insulating protection tube 22 and causing burns, making the operation safer.

[0041] The tail gas separation device of the tubular reactor also includes a temperature detection member, which is used to detect the heating temperature of the heating component 2. The temperature detection member can be a K-type thermocouple, and the heating temperature of the heating component 2 is controlled by the detection of the temperature detection member to achieve accurate control of the heating temperature. The specific structure and working principle of the temperature detection member can be set with reference to the prior art, and this embodiment will not be described in detail here.

[0042] In order to improve the protective effect of the outer protective shell 3, a cooling cavity 31 is provided in the outer protective shell 3, and a water inlet 32 ​​and a water outlet 33 connected to the cooling cavity 31 are also provided on the outer protective shell 3, and the water inlet 32 ​​and the water outlet 33 are connected to an external cooling device. The cooling water of the external cooling device enters the cooling cavity 31 through the water inlet 32, cools the outer protective shell 3, and is then discharged through the water outlet 33, forming a circulating cooling to prevent the temperature of the outer protective shell 3 from being too high. Preferably, the water inlet 32 ​​is arranged at the lower part of the outer protective shell 3, and the water outlet 33 is arranged at the upper part of the outer protective shell 3, to ensure that the cooling cavity 31 can be filled with coolant.

[0043] The tubular reactor tail gas separation device also includes a connecting flange 4, which is used to connect the combustion tower equipment and the gas recovery equipment. The separation tube assembly 1 is provided with an outlet flange 13, which is sleeved on the outside of the outer protective shell 3 and is arranged at one end of the gas outlet 112. The connecting flange 4 is detachably connected to the outlet flange 13 to achieve the connection between the tubular reactor tail gas separation device and the combustion tower equipment and the gas recovery equipment. The flange connection structure has good sealing performance and is easy to disassemble and assemble.

[0044] In one embodiment, the tail gas separation device of the tubular reactor realizes selective communication between a gas outlet 112 and the combustion tower equipment and the gas recovery equipment through a three-way valve (not shown in the figure). Specifically, the first interface of the three-way valve is connected to the separation tube 11, the second interface of the three-way valve is connected to the combustion tower equipment, and the third interface of the three-way valve is connected to the gas recovery equipment. When the separation tube assembly 1 is in the adsorption separation state, the first interface is connected to the third interface, and when the separation tube assembly 1 is in the heating desorption state, the first interface is connected to the second interface.

[0045] In order to realize the conductive heating of the heating wire 21 and the signal transmission of the temperature detection element, the heating assembly 2 also includes a line for transmitting current and communication signals. The heating assembly 2 is provided with an electrode flange pipe 24, and the connecting flange 4 is provided with a guide port 41. The electrode flange pipe 24 is arranged on the connecting flange 4 and connected to the guide port 41. The electrode flange pipe 24 is used to guide the line from the outside of the tubular reactor tail gas separation device into the inside, and enters between the insulating protection tube 22 and the separation tube 11 to connect the heating wire 21 or the temperature detection element.

[0046] In one embodiment, the tail gas separation device of the tubular reactor further includes a gas detection component, which is arranged at the gas outlet 112 and is used to detect silane gas. The gas detection component is communicatively connected to the heating component 2. When the gas detection component detects the presence of silane gas in the tail gas discharged from the gas outlet 112, it indicates that the adsorption of the activated carbon 12 has reached saturation. At this time, the heating component 2 needs to start working, and the tubular reactor no longer discharges tail gas into the separation tube 11; after the activated carbon 12 is heated and desorbed, the tubular reactor continues to discharge tail gas. Silane gas is prevented from entering the gas recovery equipment.

[0047] In order to improve the uniformity of the exhaust gas flow, the separation tube assembly 1 further includes at least one flow equalizer 14, which is disposed at the air inlet 111 and / or the air outlet 112 and / or the separation tube 11, and has a plurality of flow equalizer holes 141. The exhaust gas passes through the flow equalizer holes 141, and is more evenly distributed in the separation tube 11, so that the adsorption effect of the activated carbon 12 is better.

[0048] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A tubular reactor tail gas separation device, used for separating tail gas from a tubular reactor, characterized in that: The tail gas separation device of a tubular reactor comprises a separation tube assembly (1) and a heating assembly (2). The separation tube assembly (1) comprises a separation tube (11) and activated carbon (12) filled in the separation tube (11). The activated carbon (12) is used to adsorb silane gas in the tail gas. The heating assembly (2) is used to heat the activated carbon (12) to desorb the silane gas. The air inlet (111) of the separation tube (11) is connected to the tubular reactor. The air outlet (112) of the separation tube (11) can be selectively connected to a combustion tower device or a gas recovery device. The separation tube assembly (1) has an adsorption separation state and a heating desorption state. When the separation tube assembly (1) is in the adsorption separation state, the air outlet (112) is connected to the gas recovery device. When the separation tube assembly (1) is in the heating desorption state, the air outlet (112) is connected to the combustion tower device.

2. The tail gas separation device of the tubular reactor according to claim 1, characterized in that: The heating component (2) comprises a heating metal wire (21), and the heating metal wire (21) is wound around the outside of the separation tube (11).

3. The tail gas separation device of the tubular reactor according to claim 2, characterized in that: The heating component (2) further comprises an insulating protection tube (22), wherein the insulating protection tube (22) is sleeved on the outer side of the heating metal wire (21); and / or, The heating wire (21) extends along the axial direction of the separation tube (11) and is bent and rotated multiple times to form an S-shape so as to surround the outer circumference of the separation tube (11); and / or, The heating component (2) further comprises a supporting ceramic ring (23), wherein the supporting ceramic ring (23) is sleeved on the outer circumference of the separation tube (11), and the heating metal wire (21) is passed through the supporting ceramic ring (23).

4. The tail gas separation device of the tubular reactor according to claim 3, characterized in that: The tubular reactor tail gas separation device further comprises an outer protective shell (3), wherein the outer protective shell (3) is sleeved on the outer side of the insulating protection tube (22).

5. The tail gas separation device of the tubular reactor according to claim 4, characterized in that: A cooling cavity (31) is provided in the outer protective shell (3), and a water inlet (32) and a water outlet (33) communicating with the cooling cavity (31) are provided on the outer protective shell (3), and the water inlet (32) and the water outlet (33) are connected to an external cooling device.

6. The tail gas separation device of the tubular reactor according to claim 1, characterized in that: The tubular reactor tail gas separation device also includes a connecting flange (4), which is used to connect the combustion tower equipment and the gas recovery equipment. The separation tube assembly (1) is provided with an outlet flange (13), and the connecting flange (4) is detachably connected to the outlet flange (13).

7. The tail gas separation device of the tubular reactor according to claim 6, characterized in that: The heating component (2) further comprises a circuit and an electrode flange tube (24); the connecting flange (4) is provided with a guide port (41); the electrode flange tube (24) is arranged on the connecting flange (4) and is connected to the guide port (41); the electrode flange tube (24) is used to guide the circuit.

8. The tail gas separation device of a tubular reactor according to any one of claims 1 to 7, characterized in that: The tubular reactor tail gas separation device also includes a three-way valve, a first interface of the three-way valve is connected to the separation tube (11), a second interface of the three-way valve is connected to the combustion tower equipment, and a third interface of the three-way valve is connected to the gas recovery equipment. When the separation tube assembly (1) is in the adsorption separation state, the first interface is connected to the third interface, and when the separation tube assembly (1) is in the heating desorption state, the first interface is connected to the second interface.

9. The tail gas separation device of a tubular reactor according to any one of claims 1 to 7, characterized in that: The tubular reactor tail gas separation device further comprises a gas detection component, the gas detection component is arranged at the gas outlet (112), the gas detection component is used to detect the silane gas, and the gas detection component is communicatively connected to the heating component (2); and / or, The tubular reactor tail gas separation device further comprises a temperature detection component, wherein the temperature detection component is used to detect the heating temperature of the heating component (2).

10. The tail gas separation device of a tubular reactor according to any one of claims 1 to 7, characterized in that: The separation tube assembly (1) further comprises at least one flow equalizer plate (14), wherein the flow equalizer plate (14) is arranged at the air inlet (111) and / or the air outlet (112) and / or the separation tube (11), and a plurality of flow equalizer holes (141) are provided on the flow equalizer plate (14).

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