A flat-channel horizontal MOCVD nozzle

Abstract

This invention relates to a flat-channel horizontal MOCVD nozzle, belonging to the field of semiconductor material preparation technology. It solves the problems of uneven growth rates between the center and edges, poor uniformity of the formed film, and low precursor utilization in existing technologies for large-size substrates (8 inches and above). The invention includes an inlet pipe and an inlet chamber. The inlet pipe comprises a first inlet pipe, a second inlet pipe, and a third inlet pipe. The first inlet pipe is used to introduce ammonia gas, the second inlet pipe is used to introduce the MO source and carrier gas, and the third inlet pipe is used to introduce ammonia gas. The first end of the third inlet pipe is connected to the inlet chamber, and the second end is connected to the reaction chamber. The first end of the second inlet pipe is higher than the first end of the third inlet pipe but lower than the first end of the first inlet pipe. This invention can improve the utilization rate of MO and the uniformity of the formed film.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor material preparation technology, and in particular to a flat-channel horizontal MOCVD nozzle. Background Technology

[0002] In MOVCD (Metal-Organic Chemical Vapor Deposition) epitaxial growth processes, preventing pre-reactions and improving uniformity are the two most important and pressing issues to be addressed. Existing atmospheric pressure MOCVD processes for large substrates (8 inches and above) exhibit differences in growth rates between the center and edges, and the utilization rate of the MO (metal-organic compound) source is generally below 55%, resulting in significant material waste. Furthermore, pre-reactions in the gas phase are prone to occur, leading to poor film uniformity, high defect density, and low precursor utilization. Utility Model Content

[0003] Based on the above analysis, the present invention aims to provide a flat-channel horizontal MOCVD nozzle to solve the problems of different growth rates between the center and the edge, poor uniformity of the formed film, and low utilization rate of precursors in large-size substrates of 8 inches and above in the prior art.

[0004] The objective of this utility model is mainly achieved through the following technical solutions:

[0005] A flat-channel horizontal MOCVD nozzle is used to introduce gas into an MOCVD reaction chamber; the nozzle includes an inlet pipe and an inlet chamber.

[0006] The air inlet pipe includes a first air inlet pipe, a second air inlet pipe, and a third air inlet pipe; the first air inlet pipe is used to introduce ammonia gas, the second air inlet pipe is used to introduce the MO source and carrier gas, and the third air inlet pipe is used to introduce ammonia gas.

[0007] The first air inlet pipe, the second air inlet pipe and the third air inlet pipe each include a first end and a second end, the first end being connected to the air inlet chamber and the second end being connected to the reaction chamber;

[0008] The second end of the second intake pipe is higher than the second end of the third intake pipe and lower than the second end of the first intake pipe.

[0009] Furthermore, the first air intake pipe, the second air intake pipe, and the third air intake pipe are horizontally stacked.

[0010] Furthermore, the first air intake pipe is located in the upper layer, the second air intake pipe is located in the middle layer, and the third air intake pipe is located in the lower layer.

[0011] Furthermore, the air intake chamber includes a first air intake chamber, a second air intake chamber, and a third air intake chamber; the bottom of the second air intake chamber is higher than the bottom of the third air intake chamber and lower than the bottom of the first air intake chamber.

[0012] Furthermore, the first end of the first intake pipe is connected to the bottom of the first intake chamber, the first end of the second intake pipe is connected to the bottom of the second intake chamber, and the first end of the third intake pipe is connected to the bottom of the third intake chamber.

[0013] Furthermore, the bottom of the first air intake chamber, the second air intake chamber, and the third air intake chamber are provided with vent holes, which are respectively connected to the first air intake pipe, the second air intake pipe, and the third air intake pipe.

[0014] Furthermore, it also includes nozzles, which include a first nozzle, a second nozzle, and a third nozzle. The first nozzle is in communication with the first air intake chamber; the second nozzle is in communication with the second air intake chamber; and the third nozzle is in communication with the third air intake chamber.

[0015] Furthermore, it also includes a water box, one end of which is connected to the air intake chamber, and the other end of which is connected to the reaction chamber.

[0016] Furthermore, the water box has an inner cavity for accommodating the first air inlet pipe, the second air inlet pipe, and the third air inlet pipe.

[0017] Furthermore, the water box is equipped with cooling water, which is used to reduce the temperature of the first air intake pipe, the second air intake pipe and the third air intake pipe.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] (1) In this utility model, when the air inlet pipe introduces air into the reaction chamber, the air is introduced in layers. The middle layer is MO gas, and the upper and lower layers are ammonia gas, which realizes multi-zone gas control and effectively controls the gas density of each layer. Since the MO deposition time is proportional to the channel height, the greater the channel height, the longer the deposition time. The lower layer is preferentially mixed with the middle layer for reaction. After a certain distance, the ammonia density in the lower layer decreases and the ammonia in the upper layer compensates, which promotes the material to grow well even at a position far from the air inlet. This shortens the reaction distance by 75%, reduces the spray head-substrate distance by 34%, improves the MO source utilization rate, effectively shortens the reaction time of the reaction chamber of large-size substrates of 8 inches or more, and improves the growth uniformity.

[0020] (2) The air inlet pipe is directly connected to the reaction chamber and the air inlet chamber, which can avoid gas diffusion leakage or turbulent flow, and ensure that all the gas passing through the air inlet chamber enters the reaction chamber in a directional manner, reducing material waste.

[0021] (3) The intake pipe is horizontally stacked in the water box. The cooling water in the water box is used to cool the intake pipe. Compared with the conventional cooling method of using cooling water pipe, it occupies less space, is more compact, has a better cooling effect, and improves the life of the intake pipe.

[0022] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages will become apparent from the description or be learned by practicing this invention. The objectives and other advantages of this invention can be realized and obtained from the details specifically pointed out in the text and accompanying drawings. Attached Figure Description

[0023] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0024] Figure 1 This is a schematic diagram of the nozzle structure in a specific embodiment;

[0025] Figure 2 This is a schematic diagram of the gas intake state in the flow channel cross-section of the reaction chamber, as shown in a specific embodiment.

[0026] Figure label:

[0027] 1-First air inlet chamber; 2-Second air inlet chamber; 3-Third air inlet chamber; 4-First air inlet pipe; 5-Second air inlet pipe; 6-Third air inlet pipe; 7-Water box; 8-First nozzle; 9-Second nozzle; 10-Third nozzle; 11-Substrate; 12-Reaction chamber. Detailed Implementation

[0028] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0029] A specific embodiment of this utility model is as follows: Figure 1 As shown, a flat-channel horizontal MOCVD nozzle is disclosed for introducing gas into the MOCVD reaction chamber, including an inlet pipe and an inlet chamber.

[0030] The intake pipe includes a first intake pipe 4, a second intake pipe 5, and a third intake pipe 6. The first intake pipe 4 is used to introduce ammonia, the second intake pipe 5 is used to introduce the MO source and carrier gas, and the third intake pipe 6 is used to introduce ammonia.

[0031] The first air inlet pipe 4, the second air inlet pipe 5, and the third air inlet pipe 6 each include a first end and a second end. The first end is connected to the air inlet chamber, and the second end is connected to the reaction chamber 12.

[0032] The second end of the second intake pipe 5 is higher than the second end of the third intake pipe 6, but lower than the second end of the first intake pipe 4.

[0033] In this embodiment, the gas inlet pipe introduces gas into the reaction chamber in layers. The middle layer is MO gas, while the upper and lower layers are ammonia gas, achieving multi-zone gas control and effectively controlling the gas density of each layer. Since the compound deposition rate is related to the height in the flow channel, the upper and lower layers are ammonia gas, while the middle layer is MO gas. The lower layer preferentially mixes and reacts with the middle layer. After a certain reaction distance, the ammonia density in the lower layer decreases, and the upper layer compensates with ammonia, which promotes good material growth even at locations far from the gas inlet. This shortens the reaction distance by 75%, reduces the spray head-substrate distance by 34%, improves MO source utilization, effectively shortens the reaction time of reaction chambers with large substrates of 8 inches or more, and improves growth uniformity.

[0034] Specifically, it also includes a water box 7, one end of which is connected to the air intake chamber, and the other end is connected to the reaction chamber 12. Exemplarily, the water box 7 is made of stainless steel. The water box 7 has an inner cavity for accommodating the air intake pipe. The inner cavity is filled with cooling water to reduce the temperature of the air intake pipe and improve its lifespan. In this embodiment, the air intake pipe is horizontally stacked within the water box, and the cooling water within the water box 7 centrally cools the air intake pipe. Compared to the conventional method of using cooling water pipes, this method occupies less space, is more compact, has better cooling effect, and improves the lifespan of the air intake pipe.

[0035] The intake pipe includes a first intake pipe 4, a second intake pipe 5, and a third intake pipe 6. The first intake pipe 4 is used to introduce ammonia gas, the second intake pipe 5 is used to introduce the MO source and carrier gas, and the third intake pipe 6 is used to introduce ammonia gas. For example, the first intake pipe 4, the second intake pipe 5, and the third intake pipe 6 are all made of stainless steel.

[0036] In the growth of MO materials, the MO source must be mixed with ammonia gas to achieve material deposition; neither can be omitted. However, if the gases are completely mixed too early before entering the reaction zone, it will trigger a violent gas-phase pre-reaction, which will not only reduce the utilization efficiency of the raw materials but also affect the crystal quality of the final material. In the horizontal gas inlet method, since the lower gas layer is closer to the high-temperature region, ammonia gas will preferentially react with the MO source, resulting in a gradual decrease in the ammonia concentration downstream along the gas flow direction, thus causing uneven growth on the surface of substrate 11. Therefore, it is necessary to supplement ammonia gas from the upper layer to compensate for the amount of ammonia gas reduced by the reaction in the downstream area, ensuring uniform material growth across the entire surface of substrate 11.

[0037] The first air inlet pipe 4, the second air inlet pipe 5, and the third air inlet pipe 6 each include a first end, a second end, and an intermediate section. The first end connects to the air inlet chamber, the second end connects to the reaction chamber 12, and the intermediate section is horizontally stacked within the water box 7. During air intake, air enters from the corresponding air inlet chamber through the first end of the air inlet pipe. The gas is then transported through the intermediate section to the second end and output to the reaction chamber 12. This process avoids gas diffusion, leakage, or turbulent flow, ensuring that all gas entering the air inlet chamber is directed into the reaction chamber, thus reducing material waste.

[0038] Specifically, the middle section of the first air intake pipe 4 is located in the upper layer, the middle section of the second air intake pipe 5 is located in the middle layer, and the middle section of the third air intake pipe 6 is located in the lower layer, thereby achieving horizontal air intake.

[0039] The air intake chamber includes a first air intake chamber 1, a second air intake chamber 2, and a third air intake chamber 3. The bottom of the second air intake chamber 2 is higher than the bottom of the third air intake chamber 3, but lower than the bottom of the first air intake chamber 1.

[0040] The first end of the first air intake pipe 4 is connected to the bottom of the first air intake chamber 1, the first end of the second air intake pipe 5 is connected to the bottom of the second air intake chamber 2, and the first end of the third air intake pipe 6 is connected to the bottom of the third air intake chamber 3.

[0041] For example, the bottom of the first air intake chamber 1, the second air intake chamber 2 and the third air intake chamber 3 are provided with vent holes, which are respectively connected to the first air intake pipe 4, the second air intake pipe 5 and the third air intake pipe 6.

[0042] For example, the second end of the second intake pipe 5 is higher than the second end of the third intake pipe 6 and lower than the second end of the first intake pipe 4, such as... Figure 2 As shown, this arrangement forms an upper layer of ammonia, a middle layer of MO source and carrier gas, and a lower layer of ammonia when gas is introduced into reaction chamber 12. This avoids localized over-reaction and "dead zones" where gas concentrates in a certain area of ​​the reaction chamber. Both the upper and lower layers of ammonia can react with the middle layer of MO source, achieving multi-zone gas control and effectively controlling the gas density at each level. This ensures that the upper, middle, and lower layers of ammonia, along with the carrier gas and the lower layer, are introduced in the required proportions, thereby improving the utilization rate and deposition rate of the MO source.

[0043] The heights of the second ends of the first air inlet pipe 4, the second air inlet pipe 5, and the third air inlet pipe 6 entering the reaction chamber 12 decrease sequentially. Since the MO deposition time is proportional to the channel height, the greater the channel height, the longer the deposition time. Therefore, the deposition time of the first air inlet pipe 4, the second air inlet pipe 5, and the third air inlet pipe 6 decreases sequentially. The ammonia in the first air inlet pipe 4 enters the reaction chamber 12 last. At this time, the ammonia in the third air inlet pipe 6 has reacted with the MO in the second air inlet pipe 5 for a period of time. The ammonia concentration downstream along the airflow direction gradually decreases, requiring supplemental ammonia from the upper layer to compensate for the reduced ammonia amount in the downstream area due to reaction consumption. At this time, the ammonia in the first air inlet pipe 4 reacts with the MO in the second air inlet pipe 5, allowing the substrate 11 to react even at locations far from the air inlet, ensuring uniform material growth on the entire surface of the substrate 11, further improving MO utilization and enhancing the uniformity of the formed film.

[0044] Furthermore, it also includes nozzles, which are disposed on one side of the intake chamber. The nozzles include a first nozzle 8, a second nozzle 9, and a third nozzle 10. The first nozzle 8 is connected to the first intake chamber 1, the second nozzle 9 is connected to the second intake chamber 2, and the third nozzle 10 is connected to the third intake chamber 3.

[0045] The first nozzle 8, the second nozzle 9, and the third nozzle 10 correspond to the gas output of different air intake chambers.

[0046] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A flat-channel horizontal MOCVD nozzle, characterized in that, The nozzle is used to introduce gas into the MOCVD reaction chamber; the nozzle includes an inlet pipe and an inlet chamber. The air intake pipe includes a first air intake pipe (4), a second air intake pipe (5) and a third air intake pipe (6); the first air intake pipe (4) is used to introduce ammonia, the second air intake pipe (5) is used to introduce MO source and carrier gas, and the third air intake pipe (6) is used to introduce ammonia. The first air inlet pipe (4), the second air inlet pipe (5) and the third air inlet pipe (6) each include a first end and a second end. The first end is connected to the air inlet chamber and the second end is connected to the reaction chamber (12). The second end of the second air intake pipe (5) is higher than the second end of the third air intake pipe (6) and lower than the second end of the first air intake pipe (4).

2. The flat-channel horizontal MOCVD nozzle according to claim 1, characterized in that, The first air intake pipe (4), the second air intake pipe (5), and the third air intake pipe (6) are horizontally stacked.

3. The flat-channel horizontal MOCVD nozzle according to claim 2, characterized in that, The first air intake pipe (4) is located on the upper layer, the second air intake pipe (5) is located on the middle layer, and the third air intake pipe (6) is located on the lower layer.

4. The flat-channel horizontal MOCVD nozzle according to claim 1, characterized in that, The air intake chamber includes a first air intake chamber (1), a second air intake chamber (2), and a third air intake chamber (3); the bottom of the second air intake chamber (2) is higher than the bottom of the third air intake chamber (3) and lower than the bottom of the first air intake chamber (1).

5. The flat-flown horizontal MOCVD showerhead of claim 4, wherein, The first end of the first air intake pipe (4) is connected to the bottom of the first air intake chamber (1), the first end of the second air intake pipe (5) is connected to the bottom of the second air intake chamber (2), and the first end of the third air intake pipe (6) is connected to the bottom of the third air intake chamber (3).

6. The flat-flown horizontal MOCVD showerhead of claim 5, wherein, Ventilation holes are provided at the bottom of the first air intake chamber (1), the second air intake chamber (2) and the third air intake chamber (3), and the ventilation holes are respectively connected to the first air intake pipe (4), the second air intake pipe (5) and the third air intake pipe (6).

7. The flat-flown horizontal MOCVD showerhead of claim 4, wherein, It also includes nozzles, which include a first nozzle (8), a second nozzle (9) and a third nozzle (10). The first nozzle (8) is connected to the first air intake chamber (1); the second nozzle (9) is connected to the second air intake chamber (2); and the third nozzle (10) is connected to the third air intake chamber (3).

8. The flat-flown horizontal MOCVD showerhead of claim 1, wherein, It also includes a water box (7), one end of which is connected to the air intake chamber, and the other end of which is connected to the reaction chamber (12).

9. The flat-flown horizontal MOCVD showerhead of claim 8, wherein, The water box (7) has an inner cavity for accommodating the first air inlet pipe (4), the second air inlet pipe (5) and the third air inlet pipe (6).

10. The flat-flown horizontal MOCVD showerhead of claim 9, wherein, The water box (7) is provided with cooling water, which is used to reduce the temperature of the first air intake pipe (4), the second air intake pipe (5) and the third air intake pipe (6).

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