Diffusion furnace

Abstract

The present disclosure relates to a diffusion furnace, comprising: a base; the furnace wall is connected to the upper portion of the base, and a containing cavity is defined by the furnace wall and the upper surface of the base; the driving part is arranged on the base and located in the containing cavity, and the upper portion of the driving part is used for being connected with a wafer boat; one end of the first air channel is used for being communicated with external nitrogen, and the first air channel is used for guiding the nitrogen to a wafer boat through the base and the driving part in sequence; and the second air channel is arranged in the driving part and communicates with the first air channel, and part of air in the first air channel can directly enter the containing cavity through the second air channel. The driving part is located below the wafer boat, and the second air channel is communicated with the first air channel, so that nitrogen can directly enter the containing cavity from the second air channel in the driving part, the bottom in the containing cavity can be filled with the nitrogen, the yield of chemical by-products generated by condensation is reduced, the maintenance period of the diffusion furnace is effectively prolonged, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor manufacturing technology, and in particular, to a diffusion furnace. Background Art

[0002] Furnace tube machines are equipped with a motor and magnetic fluid at the bottom of the reaction chamber to rotate the wafer boat, ensuring a more uniform temperature and gas flow for the chemical reaction within the chamber. However, since the magnetic fluid components require cooling water to prevent excessive operating temperatures, the high-temperature chemical reaction gases within the chamber, when in contact with the cooled magnetic fluid components, experience a significant temperature difference. Consequently, the chemical gases within the chamber are easily cooled, leading to the accumulation of chemical byproducts at the bottom of the chamber. The rotation of the components also causes the chemical byproducts to move, creating a source of microparticles. In severe cases, this can lead to product failure due to excessive microparticle adhesion. Utility Model Content

[0003] The present disclosure aims to provide a diffusion furnace to solve the problem that chemical byproducts are easily deposited on the bottom of the receiving chamber.

[0004] In order to achieve the above objectives, the present disclosure provides a diffusion furnace, comprising:

[0005] base;

[0006] A furnace wall is connected to the upper portion of the base, wherein the furnace wall and the upper surface of the base together form a receiving cavity;

[0007] A driving portion is provided on the base and located in the accommodating cavity, and the upper portion of the driving portion is used to connect with the wafer boat and drive the wafer boat to rotate;

[0008] a first gas channel, one end of which is used to communicate with external nitrogen and to guide the nitrogen to the wafer boat via the base and the driving part in sequence; and

[0009] The second air channel is provided in the driving portion and communicates with the first air channel, and can allow part of the gas in the first air channel to directly enter the accommodating cavity through the second air channel.

[0010] Optionally, the driving unit includes:

[0011] A power member connected above the base;

[0012] a first carrier plate, sleeved on the outside of the power member, wherein the second air channel is at least partially provided in the first carrier plate, so that the gas in the first air channel can be guided into the accommodating cavity through the first carrier plate; and

[0013] The second carrying plate is connected above the first carrying plate and is used for connecting with the wafer boat.

[0014] Optionally, the first air channel is provided in the power member, and can guide the gas to the wafer boat through the base, the power member and the second carrier plate in sequence, and the second air channel includes:

[0015] A first section, disposed in the power member and capable of communicating with the first air passage; and

[0016] The second section is arranged in the first carrying plate and has two ends respectively communicated with the first section and the accommodating cavity.

[0017] Optionally, the lower surface of the first carrying plate is spaced apart from the upper surface of the base, and the air outlet of the second section communicating with the accommodating cavity is located on the lower surface of the first carrying plate.

[0018] Optionally, the second section is an inverted L-shaped structure, and a transverse section of the inverted L-shaped structure is located on the same horizontal line as the first section.

[0019] Optionally, the power component is a motor provided with magnetic fluid.

[0020] Optionally, the first carrying plate is made of metal, and the second carrying plate is made of plastic.

[0021] Optionally, there are multiple second airways, which are connected to the first airways respectively.

[0022] Optionally, a plurality of the second air passages are circumferentially spaced apart and arranged in the driving portion.

[0023] Optionally, the number of the second air channels is 4, and they are arranged at equal intervals in the driving part.

[0024] Through the above technical solution, the driving part is located below the wafer boat, and the second air duct is connected to the first air duct, so that nitrogen can directly enter the containing chamber from the second air duct in the driving part, so that the nitrogen can fill the bottom of the containing chamber, thereby reducing the probability of chemical by-products generated by condensation after the high-temperature chemical reaction gas in the containing chamber contacts the driving part with a temperature difference and accumulating at the bottom of the containing chamber. That is, the impurity content in the reaction process of the diffusion furnace can be reduced, and the production yield of the wafer can be improved. At the same time, since the output of chemical by-products generated by condensation is reduced, the maintenance cycle of the diffusion furnace can also be effectively extended, and the maintenance cost can be reduced.

[0025] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0027] Figure 1 is a schematic diagram of a diffusion furnace according to an embodiment of the present disclosure.

[0028] Figure 2 Schematic diagram of gas flow in a diffusion furnace according to an embodiment of the present disclosure.

[0029] Figure 3 This is a schematic diagram of the connection between a power component and a first carrier plate in a diffusion furnace according to an embodiment of the present disclosure.

[0030] Figure 4 This is a schematic diagram of a power component and a base in a diffusion furnace according to an embodiment of the present disclosure.

[0031] Figure 5 This is a top view of a power component and a base in a diffusion furnace according to an embodiment of the present disclosure.

[0032] Figure 6 Schematic diagram of a first carrier plate in a diffusion furnace according to an embodiment of the present disclosure.

[0033] Figure 7 1 is a top view of a first carrier plate in a diffusion furnace according to an embodiment of the present disclosure.

[0034] Description of Reference Numerals

[0035] 1-base; 2-furnace wall; 20-accommodating chamber; 3-driving part; 30-second air duct; 301-first section; 302-second section; 31-power part; 32-first carrier plate; 321-air outlet; 33-second carrier plate; 4-first air duct; 5-nitrogen pipeline. DETAILED DESCRIPTION

[0036] The following describes the specific embodiments of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0037] In this disclosure, unless otherwise indicated, directional terms such as "upper" and "lower" are defined relative to the actual layout of the diffusion furnace during use, and directional terms such as "inner" and "outer" are defined relative to the outlines of the corresponding components. Terms such as "first" and "second" are used to distinguish between different components and do not imply order or importance. Furthermore, in the following description, when referring to the drawings, unless otherwise indicated, identical reference numerals in different figures indicate identical or similar elements.

[0038] According to one embodiment of the present disclosure, Figures 1 to 7As shown, a diffusion furnace is provided, which may include a base 1, a furnace wall 2, a driving part 3, a first gas channel 4 and a second gas channel 30. The furnace wall 2 may be connected to the top of the base 1, and the furnace wall 2 and the upper surface of the base 1 together form a receiving chamber 20. The driving part 3 is arranged on the base 1 and is located in the receiving chamber 20. The top of the driving part 3 is used to connect the crystal boat and can drive the crystal boat to rotate. One end of the first gas channel 4 can be used to connect to external nitrogen and to guide the nitrogen to the crystal boat via the base 1 and the driving part 3 in sequence. Here, a nitrogen pipeline 5 connected to an external nitrogen source may be provided on the outside of the base 1, and the nitrogen pipeline 5 may be connected to the first gas channel 4. The second gas channel 30 is arranged in the driving part 3 and is connected to the first gas channel 4, so that part of the gas in the first gas channel 4 can directly enter the receiving chamber 20 through the second gas channel 30.

[0039] Through the above technical solution, the driving part 3 is located below the wafer boat, and the second air channel 30 is connected to the first air channel 4, so that nitrogen can directly enter the accommodating chamber 20 from the second air channel 30 in the driving part 3, so that the nitrogen can fill the bottom of the accommodating chamber 20, thereby reducing the probability that chemical by-products generated by condensation after the high-temperature chemical reaction gas in the accommodating chamber 20 contacts the driving part 3 with a temperature difference and accumulate at the bottom of the accommodating chamber 20. That is, the impurity content in the reaction process of the diffusion furnace can be reduced, and the production yield of the wafer can be improved. At the same time, since the output of chemical by-products generated by condensation is reduced, the maintenance cycle of the diffusion furnace can also be effectively extended, and the maintenance cost can be reduced.

[0040] It should be noted that nitrogen can be filled into the containing chamber 20 before the diffusion reaction, or can be added into the containing chamber 20 at any time according to the detection situation during the process, and this disclosure does not limit this. Figures 3 to 7 As shown, the number of the second air channels 30 can be multiple, and they can be connected to the first air channels 4 respectively, so as to facilitate the multi-directional delivery of nitrogen to the accommodating chamber 20, reducing the possibility of local generation of chemical byproducts at the bottom of the accommodating chamber 20 due to uneven distribution of nitrogen. A plurality of second air channels 30 can also be arranged circumferentially at intervals in the driving portion 3, so that the nitrogen can be more evenly delivered to the accommodating chamber 20. Specifically, as shown in the figure, the second air channels 30 can be arranged circumferentially at equal intervals in the driving portion 3, or can be arranged at unequal intervals, and the present disclosure does not limit this. When the second air channels 30 are arranged at equal intervals in the driving portion 3, the number of the second air channels 30 can be 4 or 8, so as to facilitate the more even delivery of nitrogen to the accommodating chamber 20, so as to reduce the possibility of chemical byproducts being generated at the bottom of the accommodating chamber 20.

[0041] Furthermore, if Figures 1 to 7As shown, the driving part 3 may include a power member 31, a first carrier plate 32, and a second carrier plate 33. The power member 31 may be connected to the top of the base 1. The first carrier plate 32 may be sleeved on the outside of the power member 31, and the second air channel 30 may be at least partially arranged in the first carrier plate 32, so that the gas in the first air channel 4 may be guided into the accommodating chamber 20 through the first carrier plate 32. The second carrier plate 33 may be connected above the first carrier plate 32 and used to connect to the crystal boat. Here, the first carrier plate 32 is an annular structure, and after being connected to the power member 31, when the upper surface of the first carrier plate 32 is higher than the upper surface of the power member 31, the gap between the upper surface of the power member 31 and the upper surface of the first carrier plate 32 may be formed as part of the first air channel 4. At this time, the air inlet of the second air channel 30 may be higher than the surface of the power member 31. In this way, the second air channel 30 may be arranged only in the first carrier plate 32. The second air channel 30 can also be provided in the first carrier plate 32 and the power member 31, that is, the second air channel 30 can include a first section 301 and a second section 302. Figures 3 to 7 As shown, in this case, the first gas channel 4 can be disposed in the power member 31, allowing the gas to sequentially pass through the base 1, the power member 31, and the second carrier plate 33 to the wafer boat. The first section 301 can be disposed in the power member 31 and can communicate with the first gas channel 4. The second section 302 can be disposed in the first carrier plate 32, with its two ends respectively communicating with the first section 301 and the accommodating chamber 20. In this way, the nitrogen in the first gas channel 4 sequentially passes through the first section 301 and the second section 302, through the power member 31 and the first carrier plate 32, and then reaches the accommodating chamber 20.

[0042] Specifically, the power element 31 can be a motor equipped with a magnetic fluid to drive the rotation of the first carrier plate 32 and the second carrier plate 33, thereby driving the rotation of the wafer boat above the second carrier plate 33, ensuring more uniform temperature and gas flow during the chemical reaction within the accommodating chamber 20. The first carrier plate 32 is made of metal, while the second carrier plate 33 is made of plastic. Specifically, the first carrier plate 32 can be iron, while the second carrier plate 33 can be engineering plastic. Engineering plastic effectively isolates heat conduction to the wafer boat, preventing the boat from overheating. The iron material cooperates with the magnetic fluid in the magnetic fluid motor, directly driving the rotation of the first carrier plate 32 through magnetic force, reducing mechanical contact, noise, and friction.

[0043] Furthermore, if Figure 3 、 Figure 6 and Figure 7As shown, the lower surface of the first carrier plate 32 is spaced apart from the upper surface of the base 1 to facilitate the rotation of the first carrier plate 32 and the second carrier plate 33 and prevent friction between them and the base 1. Because cooling water circulates within the power element 31, the temperature difference between the surface of the power element 31 and the interior of the accommodating chamber 20 is relatively large. High-temperature chemical reaction gases are more likely to condense and produce chemical byproducts upon contact with the power element 31. Therefore, the gas outlet 321 of the second section 302, which communicates with the accommodating chamber 20, can be located on the lower surface of the first carrier plate 32. Thus, because the gas outlet 321 faces the base 1 and the point where nitrogen enters the accommodating chamber 20 is near the surface of the power element 31, the likelihood of the original chemical reaction gas remaining on the surface of the power element 31 and near the base when nitrogen is filled into the accommodating chamber 20 is reduced. This further reduces the probability of chemical byproducts produced due to temperature differences and extends the maintenance cycle of the diffusion furnace.

[0044] Specifically, the second section 302 may be an inverted L-shaped structure, with the horizontal section of the inverted L-shaped structure located on the same horizontal line as the first section 301. The inverted L-shaped structure, consisting of two straight sections, can effectively reduce the flow time of nitrogen in the first carrier plate 32, allowing nitrogen to enter the accommodating cavity 20 more quickly, creating a nitrogen atmosphere at the bottom of the accommodating cavity 20 and reducing the probability of chemical byproduct accumulation caused by high-temperature gases involved in the chemical reaction contacting the low-temperature power component 31.

[0045] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0046] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0047] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A diffusion furnace, characterized in that: include: base; A furnace wall is connected to the upper portion of the base, wherein the furnace wall and the upper surface of the base together form a receiving cavity; A driving portion is provided on the base and located in the accommodating cavity, and the upper portion of the driving portion is used to connect with the wafer boat and drive the wafer boat to rotate; a first gas channel, one end of which is used to connect to external nitrogen and to guide the nitrogen to the wafer boat via the base and the driving part in sequence; and The second air channel is provided in the driving portion and communicates with the first air channel, and can allow part of the gas in the first air channel to directly enter the accommodating cavity through the second air channel.

2. The diffusion furnace according to claim 1, characterized in that The driving unit includes: A power member connected above the base; a first carrier plate, sleeved on the outside of the power member, wherein the second air channel is at least partially provided in the first carrier plate, so that the gas in the first air channel can be guided into the accommodating cavity through the first carrier plate; and The second carrying plate is connected above the first carrying plate and is used for connecting with the wafer boat.

3. The diffusion furnace according to claim 2, characterized in that The first air channel is provided in the power member, and can guide the gas to the wafer boat through the base, the power member and the second carrier plate in sequence. The second air channel includes: A first section, disposed in the power member and capable of communicating with the first air passage; and The second section is arranged in the first carrying plate and has two ends respectively communicated with the first section and the accommodating cavity.

4. The diffusion furnace according to claim 3, characterized in that The lower surface of the first carrying plate is spaced apart from the upper surface of the base, and the air outlet of the second section communicating with the accommodating cavity is located on the lower surface of the first carrying plate.

5. The diffusion furnace according to claim 3, characterized in that The second section is an inverted L-shaped structure, and the transverse section of the inverted L-shaped structure is located on the same horizontal line as the first section.

6. The diffusion furnace according to claim 2, characterized in that The power component is a motor provided with magnetic fluid.

7. The diffusion furnace according to claim 2, characterized in that The first carrying plate is made of metal, and the second carrying plate is made of plastic.

8. The diffusion furnace according to claim 1, wherein: There are multiple second airways, and each of them is connected to the first airway.

9. The diffusion furnace according to claim 8, characterized in that A plurality of the second air passages are circumferentially spaced apart and arranged in the driving portion.

10. The diffusion furnace according to claim 9, characterized in that The number of the second air channels is four, and the second air channels are arranged at equal intervals in the driving portion.

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