Atomic layer deposition equipment

Abstract

The invention discloses atomic layer deposition equipment, and relates to the technical field of atomic layer deposition, the atomic layer deposition equipment comprises a first reaction chamber, a second reaction chamber, a third reaction chamber and a fourth reaction chamber, the first reaction chamber comprises a first arc-shaped wall and a second arc-shaped wall in the direction from the first opening to the second opening, the first arc-shaped wall is in smooth connection with the second arc-shaped wall, the arc center of the first arc-shaped wall is located on the outer side of a cavity of the first reaction chamber, and the arc center of the second arc-shaped wall is an inner cavity of the first reaction chamber; the cavity space of the first reaction chamber is gradually increased along the direction from the first opening to the second opening; and the second reaction chamber is of a groove structure for accommodating the first reaction chamber, and the end part, provided with the second opening, of the first reaction chamber is attached to the groove bottom of the second reaction chamber, so that a cavity surrounded between the inner wall of the first reaction chamber and the groove bottom of the second reaction chamber forms an atomic layer deposition reaction chamber, and the distribution uniformity of a deposited film is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of atomic layer deposition, and particularly relates to an atomic layer deposition apparatus. Background Art

[0002] In the atomic layer deposition process, precursor gases need to diffuse into the reaction chamber for thin film deposition. However, in the existing atomic layer deposition apparatus during the deposition process, due to the horizontal flow design, when the precursor gases flow parallel to the substrate surface, the deposition rate is often faster in the upstream region due to the high gas concentration, and the thin film becomes thinner in the downstream region due to the consumption of the precursor gases. The uneven gas distribution leads to fluctuations in the thin film thickness, and the rectangular reaction chamber is prone to form turbulence or gas "dead zones" in the corners, further exacerbating the uneven distribution of the thin film.

[0003] Therefore, how to improve the uniformity of the deposited thin film distribution is a technical problem that those skilled in the art need to solve currently. Summary of the Invention

[0004] The purpose of the present invention is to provide an atomic layer deposition apparatus for improving the uniformity of the deposited thin film distribution.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] An atomic layer deposition apparatus, comprising:

[0007] A first reaction chamber, which is a cavity structure with a first opening and a second opening respectively provided at both ends. The aperture of the first opening is smaller than the aperture of the second opening, and the first reaction chamber includes a first arc wall and a second arc wall along the direction from the first opening to the second opening. The first arc wall and the second arc wall are smoothly connected. The center of the arc of the first arc wall is located outside the cavity of the first reaction chamber, and the center of the arc of the second arc wall is the inner cavity of the first reaction chamber, so that the cavity space of the first reaction chamber gradually increases along the direction from the first opening to the second opening;

[0008] A second reaction chamber, which is a groove structure for accommodating the first reaction chamber. The end of the first reaction chamber with the second opening is attached to the bottom of the groove of the second reaction chamber, so that the cavity formed by the inner wall of the first reaction chamber and the bottom of the groove of the second reaction chamber forms an atomic layer deposition reaction chamber.

[0009] Optionally, in the above atomic layer deposition apparatus, the roughness range of the inner wall surface of the first arc wall and the inner wall surface of the second arc wall is 0.7 μm - 0.9 μm.

[0010] Optionally, in the above atomic layer deposition equipment, the atomic layer deposition equipment further includes a gas equalizing substrate, the gas equalizing substrate is provided with a plurality of gas equalizing holes, and the gas equalizing holes are arranged at equal intervals. The precursor gas flows into the first opening through each of the gas equalizing holes of the gas equalizing substrate.

[0011] Optionally, in the above atomic layer deposition equipment, the aperture size range of the gas equalizing holes is 2.5 mm - 3.5 mm.

[0012] Optionally, in the above atomic layer deposition equipment, the atomic layer deposition equipment further includes a diversion tube, and the gas equalizing substrate is connected to the first reaction chamber through the diversion tube, so that the gas equalizing holes are communicated with the first opening through the diversion tube.

[0013] Optionally, in the above atomic layer deposition equipment, the centers of the first opening and the second opening are both located on the axis of the diversion tube, and the axis of the diversion tube is perpendicular to the plane where the bottom of the second reaction chamber is located.

[0014] Optionally, in the above atomic layer deposition equipment, the length range of the diversion tube is 30 cm - 40 cm.

[0015] Optionally, in the above atomic layer deposition equipment, connection flanges are provided at both the end of the first reaction chamber having the first opening and the end of the diversion tube, and the connection flanges are provided with connection holes for cooperating with bolts, so that the diversion tube can be detachably installed on the first reaction chamber through the connection flanges.

[0016] Optionally, in the above atomic layer deposition equipment, the atomic layer deposition equipment is further provided with a chamber cover for covering the second reaction chamber, the chamber cover is hinged to the second reaction chamber, and the chamber cover is provided with an installation through hole, and the end of the first reaction chamber having the first opening penetrates through the installation through hole and is connected to the diversion tube.

[0017] Optionally, in the above atomic layer deposition equipment, a first air extraction port and a second air extraction port are provided at the bottom of the second reaction chamber. The first air extraction port is used for evacuating the atomic layer deposition reaction chamber, and the second air extraction port is used for evacuating the cavity surrounded by the outer wall and the inner wall of the second reaction chamber.

[0018] Compared with the prior art, when the atomic layer deposition equipment provided by the present invention is used, the precursor gas flows into the atomic layer deposition reaction cavity formed by the cooperation of the first reaction chamber and the second reaction chamber through the first opening of the first reaction chamber for deposition reaction. The first reaction chamber has a first arc wall and a second arc wall along the direction from the first opening to the second opening. The first arc wall and the second arc wall are smoothly connected. The center of the arc of the first arc wall is located outside the cavity of the first reaction chamber, and the center of the arc of the second arc wall is the inner cavity of the first reaction chamber. The cavity space of the first reaction chamber gradually increases along the direction from the first opening to the second opening, so that the overall cavity of the first reaction chamber forms a shape similar to a water droplet. Then, when the precursor gas flows from the first opening to the second opening and flows downward to the bottom of the second reaction chamber, the gradually changing area design reduces the flow velocity gradient. The arc wall surfaces of the first arc wall and the second arc wall guide the laminar flow, reduce the flow resistance, inhibit the generation of turbulence or the problem of gas "dead zones", so that the precursor gas uniformly covers the surface of the substrate, and then improves the uniformity of the distribution of the deposited film. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 is a schematic structural diagram of the atomic layer deposition equipment disclosed in the embodiment of the present invention;

[0021] Figure 2 is a schematic structural diagram of the first reaction chamber disclosed in the embodiment of the present invention;

[0022] Figure 3 is Figure 2 a cross-sectional view taken along A-A in

[0023] Figure 4 is a top view schematic diagram of the first reaction chamber disclosed in the embodiment of the present invention;

[0024] Figure 5 is a schematic structural diagram of the first air extraction port and the second air extraction port disclosed in the embodiment of the present invention

[0025] Reference numerals:

[0026] 100 is the first reaction chamber, 110 is the first opening, 120 is the second opening, 130 is the first arc wall, 140 is the second arc wall;

[0027] 200 is the second reaction chamber, 210 is the first air extraction port, 220 is the second air extraction port, 230 is the cavity cover;

[0028] 300 is the gas equalizing substrate;

[0029] 400 is a diversion tube;

[0030] 500 is a connecting flange. Specific embodiments

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined. "Several" means one or more unless otherwise specifically defined.

[0034] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0035] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" 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 directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The core of the present invention is to provide an atomic layer deposition device for improving the uniformity of the deposited film distribution.

[0037] Such as Figure 1 , Figure 2 , Figure 3 andFigure 4 As shown in Figure 4 , an embodiment of the present invention discloses an atomic layer deposition apparatus, which includes a first reaction chamber 100 and a second reaction chamber 200. Among them, the first reaction chamber 100 is a cavity structure with opposite ends. One end is provided with a first opening 110 communicating with the inner cavity, and the other end is provided with a second opening 120 communicating with the inner cavity. The aperture of the first opening 110 is smaller than that of the second opening. The precursor gas flows from the first opening 110 to the second opening 120. At the same time, the first reaction chamber 100 also has a first arc wall 130 and a second arc wall 140. The first arc wall 130 and the second arc wall 140 are smoothly connected along the direction from the first opening 110 to the second opening 120. And the center of the arc of the first arc wall 130 is located outside the cavity of the first reaction chamber 100, and the center of the arc of the second arc wall 140 is the inner cavity of the first reaction chamber 100, that is, the first arc wall 130 bulges towards the inner cavity, and the second arc wall 140 bulges outwards. The concave surface is the inner wall, so that the cavity space of the first reaction chamber 100 gradually increases along the direction from the first opening 110 to the second opening 120, and then a curved surface structure similar to the shape of a water droplet is formed. The second reaction chamber 200 is a groove structure with an accommodating space. The first reaction chamber 100 is placed into the inner cavity of the second reaction chamber 200 through the notch, and the end of the first reaction chamber 100 provided with the second opening 120 is attached to the bottom of the groove of the second reaction chamber 200. In this way, the cavity surrounded between the arc-shaped inner wall of the first reaction chamber 100 and the bottom of the groove of the second reaction chamber 200 forms an atomic layer deposition reaction cavity. That is, after placing the semiconductor to be subjected to atomic layer deposition on the bottom of the second reaction chamber 200, the first reaction chamber 100 covers the semiconductor, and the precursor gas can flow into the atomic layer deposition reaction cavity through the first opening 110 to deposit the thin film. When the precursor gas flows from the first opening 110 to the second opening 120 and flows from top to bottom, the gradually changing area of the cavity in the shape of a water droplet reduces the flow velocity gradient. The arc-shaped wall surfaces of the first arc wall 130 and the second arc wall 140 guide the laminar flow, realize laminar flow strengthening, reduce the flow resistance, suppress the generation of turbulence or the problem of gas "dead zone", so that the precursor gas uniformly covers the surface of the substrate, and then improves the uniformity of the deposition thin film distribution.

[0038] In a specific embodiment, the roughness range of the inner wall surface of the first arc-shaped wall 130 and the inner wall surface of the second arc-shaped wall 140 is 0.7 μm - 0.9 μm, and specifically can be set to 0.7 μm, 0.8 μm, or 0.9 μm. The electrolytic polishing and chemical etching composite process can be used for processing, so that the inner surfaces of the first arc-shaped wall 130 and the second arc-shaped wall 140 have a high smoothness. The inner surface with a high smoothness can inhibit the boundary layer separation, reduce gas retention, reduce the adsorption effect of the wall on the precursor gas, reduce the resistance of the gas flow, and then improve the deposition efficiency and uniformity of the precursor gas. If the roughness of the inner surface is greater than this range, the relatively rough surface is likely to cause micro-turbulence, which is not conducive to the flow and uniform diffusion of the precursor gas. If the roughness of the inner surface is less than this range, it will increase the processing difficulty of the parts and increase the manufacturing cost.

[0039] As Figure 1 shown, the atomic layer deposition equipment provided in this embodiment further includes a gas equalizing substrate 300. The gas equalizing substrate 300 is provided with a plurality of gas equalizing holes, and the gas equalizing holes are arranged at intervals. The axis of each gas equalizing hole is perpendicular to the bottom plane of the second reaction chamber 200 to form a vertical gas flow. In this way, after the precursor gas passes through the gas equalizing holes of the gas equalizing substrate 300, it then flows to the first opening 110 and then flows into the atomic layer deposition reaction chamber. Therefore, before the precursor gas flows into the atomic layer deposition reaction chamber, it is divided into multiple fine streams by the gas equalizing holes of the gas equalizing substrate 300, optimizing the gas flow uniformity. By designing the gradient of each gas equalizing hole diameter, the diffusion loss is accurately compensated, solving the problem that the existing single-hole gas intake is prone to too strong central gas flow and insufficient edge deposition, improving the utilization rate of the precursor gas, reducing the raw material cost, and further enhancing the uniformity of the deposited thin film.

[0040] In a specific embodiment, the aperture size range of the gas equalizing holes is 2.5 mm - 3.5 mm, and specifically can be set to 2.5 mm, 3 mm, or 3.5 mm. The gas equalizing substrate 300 can be made of corrosion-resistant stainless steel, and the gas equalizing holes are machined by laser. Also, the hole walls of the gas equalizing holes are polished to reduce the surface roughness and reduce the gas flow turbulence generated by the inner surface roughness, improving the gas flow velocity and uniformity. If the aperture size of the gas equalizing holes is less than this range, it may cause too large a pressure drop, resulting in an increase in gas flow resistance and a decrease in gas flow velocity. If the aperture size of the gas equalizing holes is greater than this range, the gas equalizing effect will be weakened.

[0041] As Figure 1As shown in the figure, the atomic layer deposition equipment provided in this embodiment further includes a flow guide pipe 400. The flow guide pipe 400 is a pipe structure with openings at both ends. The gas distribution substrate 300 is installed at one end of the flow guide pipe 400. The other end of the flow guide pipe 400 is connected to the end of the first reaction chamber 100 with a first opening 110 and is in communication with the first opening 110. In this way, each gas distribution hole of the gas distribution substrate 300 is connected to the first opening 110 through the flow guide pipe 400. That is, the precursor gas delivered from the precursor gas inlet flows into the flow guide pipe 400 after passing through each gas distribution hole of the gas distribution substrate 300. After passing through the flow guide pipe 400, the precursor gas then flows into the first opening 110 and enters the atomic layer deposition reaction chamber. Therefore, after the precursor gas passes through the cooperation of the gas distribution substrate 300 and the flow guide pipe 400, the flow guide pipe 400 extends the gas flow path, increases the diffusion time of the precursor gas in the atomic layer deposition reaction chamber, ensures the full diffusion of the precursor gas, covers the entire projection area of the substrate, improves the coverage rate of the precursor gas, further optimizes the gas flow uniformity, and promotes the uniform distribution of the deposited film.

[0042] Furthermore, the centers of the first opening 110 and the second opening 120 in the first reaction chamber 100 are both on the axis of the flow guide pipe 400, and the axis of the flow guide pipe 400 is perpendicular to the plane where the bottom of the second reaction chamber 200 is located, so that the flow guide pipe 400 is arranged perpendicular to the bottom of the second reaction chamber 200, avoiding the problem that off-axis installation will cause gas to impact the chamber wall and generate eddy currents, making the precursor gas flow more smoothly and steadily in the pipeline, facilitating the uniform diffusion of the precursor gas in the atomic layer deposition reaction chamber. At the same time, the inner wall of the first reaction chamber 100 is axisymmetric with respect to the axis of the centers of the first opening 110 and the second opening 120, further eliminating the position dependence, further reducing the difference in the deposition rates between the edge and the center during the diffusion process of the precursor gas, and improving the uniformity of the deposited film.

[0043] In another specific embodiment, the length of the flow guide pipe 400 is preferably set in the range of 30 cm - 40 cm, and can be specifically set to 30 cm, 35 cm, 38 cm or 40 cm. If the length of the flow guide pipe 400 is less than this range, it is not conducive to the uniform diffusion of the precursor gas. If the length of the flow guide pipe 400 is greater than this range, the length of the flow guide pipe 400 increases the ineffective volume and reduces the diffusion efficiency of the precursor gas in the atomic layer deposition reaction chamber. Of course, it can be understood that during the preparation process of the flow guide pipe 400, the inner wall surface of the flow guide pipe 400 also needs to be polished smoothly to reduce the surface roughness and improve the flow smoothness and uniformity of the precursor gas in the flow guide pipe 400.

[0044] As Figure 5As shown in the figure, connection flanges 500 are provided at the ends of the first opening 110 of the first reaction chamber 100 and the end of the flow guide pipe 400. The connection flanges 500 are provided with connection holes for mating with bolts. Then, the flow guide pipe 400 is detachably connected to the end of the first opening 110 of the first reaction chamber 100 through the connection flange 500. Similarly, the gas distribution substrate 300 can also be provided with connection holes. At this time, a connection flange 500 for mating with the gas distribution substrate 300 is also provided at the other end of the flow guide pipe 400. The gas distribution substrate 300 and the flow guide pipe 400 are also detachably connected, so as to realize the modular connection of the first reaction chamber 100, the flow guide pipe 400 and the gas distribution substrate 300, which is convenient for later disassembly, cleaning and maintenance of the cavity. Of course, a sealing gasket is provided between the connections of any two of the first reaction chamber 100, the flow guide pipe 400 and the gas distribution substrate 300 for sealing treatment to prevent gas leakage.

[0045] As Figure 1 shown in the figure, the atomic layer deposition equipment is also provided with a cavity cover 230. One side of the cavity cover 230 is installed on the housing of the second reaction chamber 200 by means of hinge. By rotating the cavity cover 230, the opening of the second reaction chamber 200 can be covered, so that the inner cavity of the second reaction chamber 200 is in a closed state. The atomic layer deposition reaction cavity formed around between the inner wall of the first reaction chamber 100 and the bottom of the groove of the second reaction chamber 200 is in a closed space, avoiding the influence of the external environment on the atomic layer deposition reaction. In addition, to realize the connection and installation of the first reaction chamber 100 and the flow guide pipe 400, an installation through hole is provided in the cavity cover 230, and the installation through hole penetrates through both sides of the cavity cover 230. The end of the first opening 110 of the first reaction chamber 100 penetrates through the installation through hole and is connected and fixed to the end of the flow guide pipe 400. Therefore, when the cavity cover 230 is rotated and opened, the first reaction chamber 100 and the cavity cover 230 can move simultaneously to lift the first reaction chamber 100 to place the semiconductor that needs atomic layer deposition. Of course, a sealing ring is provided between the outer wall of the end of the first opening 110 of the first reaction chamber 100 and the installation through hole for sealing treatment.

[0046] As Figure 5As shown, a first air extraction port 210 and a second air extraction port 220 are provided at the bottom of the second reaction chamber 200. The first air extraction port 210 is communicated with the atomic layer deposition reaction chamber. The vacuum pump extracts the waste gas in the atomic layer deposition reaction chamber through the first air extraction port 210. At the same time, due to the inner cavity of the first reaction chamber 100 being designed in a water droplet shape, and the precursor gas flowing from the precursor gas inlet through the gas distribution substrate 300, the diversion pipe 400, and the first opening 110 of the first reaction chamber 100 to the second opening 120 in a vertical flow direction from top to bottom, the discharge of by-products is accelerated, the purging efficiency is improved, and at the same time, the retention of by-products at the bottom of the second reaction chamber 200 in the atomic layer deposition reaction chamber is reduced, improving the purity of the precursor gas in the atomic layer deposition reaction chamber and enhancing the quality and process efficiency of thin film deposition. The vacuum pump can extract the gas in the cavity surrounded by the outer wall and the inner wall of the second reaction chamber 200 through the second air extraction port 220, evacuating it to a vacuum state, isolating the atomic layer deposition reaction chamber from the outside world by forming a vacuum, avoiding the influence and interference of the surrounding environment on the atomic layer deposition reaction in the atomic layer deposition reaction chamber, and ensuring the high-quality formation of the deposited thin film.

[0047] In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0048] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. An atomic layer deposition device, characterized in that: include: The first reaction chamber is a cavity structure with a first opening and a second opening respectively opened at two ends, the aperture of the first opening is smaller than the aperture of the second opening, and the first reaction chamber comprises a first arc wall and a second arc wall along the direction from the first opening to the second opening, the first arc wall is smoothly connected to the second arc wall, the arc center of the first arc wall is located outside the cavity of the first reaction chamber, and the arc center of the second arc wall is the inner cavity of the first reaction chamber, so that the cavity space of the first reaction chamber gradually increases along the direction from the first opening to the second opening; The second reaction chamber is a groove structure for accommodating the first reaction chamber. The end of the first reaction chamber having the second opening is fitted with the bottom of the second reaction chamber, so that the cavity surrounded by the inner wall of the first reaction chamber and the bottom of the second reaction chamber forms an atomic layer deposition reaction chamber.

2. The atomic layer deposition device according to claim 1, characterized in that: The roughness of the inner wall surface of the first arc-shaped wall and the inner wall surface of the second arc-shaped wall is in the range of 0.7 μm to 0.9 μm.

3. The atomic layer deposition device according to claim 1, characterized in that: The atomic layer deposition device further includes a gas equalizing substrate, the gas equalizing substrate is provided with a plurality of gas equalizing holes, each of the gas equalizing holes is evenly arranged at intervals, and the precursor gas flows into the first opening through each of the gas equalizing holes of the gas equalizing substrate.

4. The atomic layer deposition device according to claim 3, characterized in that: The pore size of the uniform pores ranges from 2.5 mm to 3.5 mm.

5. The atomic layer deposition device according to claim 3, characterized in that: The atomic layer deposition device further includes a flow guide tube, and the gas uniformity substrate is connected to the first reaction chamber through the flow guide tube, so that the gas uniformity hole is connected to the first opening through the flow guide tube.

6. The atomic layer deposition device according to claim 5, characterized in that: The center of the first opening and the center of the second opening are both on the axis of the flow guide tube, and the axis of the flow guide tube is perpendicular to the plane where the bottom of the second reaction chamber is located.

7. The atomic layer deposition device according to claim 5, characterized in that: The length of the flow guide tube ranges from 30 cm to 40 cm.

8. The atomic layer deposition apparatus according to claim 5, characterized in that: The end of the first opening of the first reaction chamber and the end of the guide tube are both provided with connecting flanges, and the connecting flanges are provided with connecting holes matched with bolts, so that the guide tube can be detachably installed on the first reaction chamber through the connecting flanges.

9. The atomic layer deposition apparatus according to claim 5, characterized in that: The atomic layer deposition equipment is also provided with a chamber cover for sealing the second reaction chamber, the chamber cover is hingedly connected to the second reaction chamber, and the chamber cover is provided with a mounting through hole, and the end of the first reaction chamber having the first opening passes through the mounting through hole and is connected to the guide tube.

10. The atomic layer deposition device according to any one of claims 1 to 9, characterized in that: The bottom of the second reaction chamber is provided with a first gas exhaust port and a second gas exhaust port, the first gas exhaust port is used to exhaust the atomic layer deposition reaction chamber, and the second gas exhaust port is used to exhaust the cavity surrounded by the outer wall of the second reaction chamber and the inner wall of the second reaction chamber.

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