A thin film deposition apparatus

Abstract

This invention discloses a thin film deposition apparatus, comprising: a vacuum reaction chamber having an inlet opening and an outlet opening, the inlet opening for supplying process gas into the vacuum reaction chamber in a horizontal direction; a substrate assembly disposed within the vacuum reaction chamber, the substrate assembly including a support surface for supporting a substrate; the vacuum reaction chamber including an inlet region corresponding to the inlet opening, an outlet region corresponding to the outlet opening, and a processing region located between the inlet region and the outlet region; the direction from the inlet region to the outlet region is defined as the length direction of the thin film deposition apparatus, and the direction perpendicular to the length direction in the horizontal plane is defined as its width direction; along the path from the processing region to the outlet region, at least a portion of the width of the processing region continuously decreases along the length direction. This apparatus can increase the density of process gas in the region where the width of the processing region decreases, thereby increasing the thin film growth rate of the substrate in that region.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment, and more specifically to a thin film deposition apparatus. Background Technology

[0002] Metal-organic chemical vapor deposition (MOCVD) is an advanced chemical vapor deposition (CVD) technology primarily used to grow thin layers of various III-V and II-VI compound semiconductors and their multi-component solid solutions on substrates. Due to its high-quality material growth characteristics, it is widely used in various fields, such as semiconductor manufacturing, LED production, solar cell manufacturing, novel material synthesis, and heterogeneous integration.

[0003] In MOCVD, the thin film deposition apparatus typically heats a tray via a heating device, raising the substrate on the tray to the required growth temperature. At this high temperature, metal atoms react chemically with other chemicals in the reaction chamber, forming a thin film on the substrate surface. As the reaction proceeds, metal atoms are continuously deposited on the substrate surface, thus forming a uniform and continuous thin film.

[0004] In MOCVD, the performance evaluation of thin film deposition apparatus typically includes three important indicators: 1) the uniformity of the grown film, mainly referring to the uniformity of thickness; 2) the interfaces within the film, which refer to the fluctuations in the growth rate of various points on the substrate over time during the film growth process; the greater the fluctuation, the worse the interface; and 3) source efficiency, which refers to the proportion of material source (such as TMGA) used in the substrate film growth. The performance of these indicators reflects the production performance of the thin film deposition apparatus. However, in practical applications, it may be difficult to achieve a comprehensive balance among these indicators, and focusing on improving one indicator may disrupt the balance of others. This is especially true in existing horizontal thin film deposition apparatuses with large substrates (e.g., 300mm substrates), where the deposition uniformity across the entire substrate is crucial. However, existing thin film deposition apparatuses struggle to achieve optimal synergy across all factors. Therefore, improvements to existing apparatuses are necessary.

[0005] It is understood that the above statements only provide background information related to the present invention and do not necessarily constitute prior art. Summary of the Invention

[0006] Based on the aforementioned technical problems, the purpose of this invention is to provide a thin film deposition apparatus in which the width of at least a portion of the processing area continuously decreases to increase the density of the process gas in that area, thereby allowing more reactants to reach the substrate surface and react, increasing the thin film growth rate of the substrate in that area. This structure helps to improve the uniformity of the thin film growth rate on the substrate surface and eliminates the weakness of square processing areas requiring the sacrifice of source efficiency to improve interface quality and thin film uniformity.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] A thin film deposition apparatus, comprising:

[0009] A vacuum reaction chamber having an inlet opening and an outlet opening, wherein the inlet opening is used to supply process gas into the vacuum reaction chamber in a horizontal direction;

[0010] A base assembly disposed within the vacuum reaction chamber, the base assembly including a bearing surface for supporting a substrate;

[0011] The vacuum reaction chamber includes an air intake area corresponding to the air intake opening, an exhaust area corresponding to the exhaust opening, and a processing area located between the air intake area and the exhaust area.

[0012] The direction from the air intake area to the exhaust area is defined as the length direction of the thin film deposition apparatus, and the direction perpendicular to the length direction in the horizontal plane is defined as the width direction of the thin film deposition apparatus. Along the path from the center of the processing area to the exhaust area, at least a portion of the width of the processing area shows a continuous decreasing trend along the length direction.

[0013] Optionally, the first end of the processing area is set to be near the air intake area, and the last end is set to be near the exhaust area, with the width of the last end of the processing area continuously decreasing.

[0014] Optionally, the length of the processing area in the length direction is set to L. Along the direction from the intake area to the exhaust area, the width of the area between the first position of the processing area and its tail end has a continuously decreasing trend. The distance between the projection of the first position in the length direction and the projection of the tail end of the processing area in the length direction is greater than or equal to 1 / 10L.

[0015] Optionally, the first position coincides with the beginning position of the processing area.

[0016] Optionally, the first position does not coincide with the beginning position of the processing area.

[0017] Optionally, the range of the first position is from the center of the processing area to a distance of 2 / 5L from the center along the length direction.

[0018] Optionally, the first end of the air intake region is defined as the end closest to the air intake opening, and the last end is defined as the end closest to the processing region, wherein the width of at least the last end region of the air intake region shows a continuous decreasing trend.

[0019] Optionally, the width of the air intake areas is the same.

[0020] Optionally, the first end of the exhaust region is defined as the end closest to the processing region, and the last end is the end closest to the exhaust opening, with the width of at least the first end of the exhaust region showing a continuous decreasing trend.

[0021] Optionally, the widths of the exhaust regions are the same.

[0022] Optionally, in the width direction, the minimum width of the intake area is not less than the maximum width of the processing area, and the minimum width of the processing area is not less than the maximum width of the exhaust area.

[0023] Optionally, along the path from the center of the processing area to the exhaust area, the width of at least a portion of the processing area decreases linearly or non-linearly.

[0024] Optionally, along the path from the center of the processing area to the exhaust area, the width of at least a portion of the processing area continuously decreases in an arc shape.

[0025] Optionally, the arc shape is a circular arc shape.

[0026] Optionally, the curvature of the arc shape is the same as the curvature of the substrate.

[0027] Optionally, along the length direction, the height of at least a portion of the processing area tends to decrease, wherein the height of the processing area is the distance between the plane containing the bearing surface and the top inner wall of the vacuum reaction chamber.

[0028] Optionally, along the length direction, the height of at least a portion of the processing area decreases linearly or non-linearly.

[0029] Optionally, the nonlinear trend is a convex curve shape or a concave curve shape.

[0030] Optionally, the height of the boundary between the processing area and the air intake area is set to L2, the minimum height of the processing area is L1, and the value of L2 / L1 is greater than 1 and less than or equal to 5.

[0031] Optionally, the intake area, the processing area, and the exhaust area are circumferentially surrounded by bushings.

[0032] Optionally, the shortest distance between the inner wall of the bushing and the edge of the substrate is greater than or equal to 10 mm.

[0033] Optionally, the top of the processing area is a top plate structure, and along the length direction, the distance between the bottom wall of the top plate structure and the plane where the bearing surface is located in the processing area decreases.

[0034] Optionally, the length of the region where the height of the top plate structure decreases is 1 to 1.5 times the length of the processing region.

[0035] Optional, also includes:

[0036] An intake assembly is disposed at the intake opening, the intake assembly comprising a main metal-organic compound source and two peripheral metal-organic compound sources, the two peripheral metal-organic compound sources being located on either side of the main metal-organic compound source.

[0037] Optionally, the base assembly includes a base, the end of the base near the exhaust opening being its tail end, and the width of the tail end region of the base continuously decreasing.

[0038] Optionally, the exhaust direction of the exhaust opening is perpendicular to the air supply direction of the air inlet opening.

[0039] Optionally, the thin film deposition apparatus is a monolithic thin film deposition apparatus.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] In summary, in the thin film deposition apparatus of the present invention, by adjusting the width of at least a portion of the processing area within the vacuum reaction chamber, the width of at least a portion of the processing area shows a continuous decreasing trend, thereby increasing the concentration of process gas in the area. This allows more process gas to reach the substrate surface and react, increasing the thin film growth rate of the substrate in that area. This structure helps to improve the uniformity of the thin film growth rate on the substrate surface and eliminates the weakness of requiring sacrifice of source efficiency to improve interface quality and thin film uniformity in square processing areas.

[0042] Furthermore, the device can further adjust the height of the processing area so that the height of at least part of the processing area tends to decrease, thereby giving the process gas a downward velocity and increasing the amount of downward mass flow of the process gas, which helps to improve the film growth rate of the substrate in this area.

[0043] Furthermore, when the width shrinkage region and the height shrinkage region of the processing area at least partially overlap, the cross-sectional area of ​​the process gas flow can be significantly reduced under the effect of dual-dimensional shrinkage, which can significantly improve the acceleration effect of the process gas flow to the substrate in this region, greatly improve the film growth rate of the substrate in this region, and avoid improving growth rate uniformity and interface quality by sacrificing source efficiency. Attached Figure Description

[0044] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the drawings in the following description are one embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0045] Figure 1 This is a schematic diagram of an existing thin film deposition apparatus;

[0046] Figure 2 for Figure 1 Top cross-sectional view of the medium vacuum reaction chamber and its internal components;

[0047] Figure 3 This is a schematic diagram of the long-speed operation under various process conditions in an existing thin film deposition apparatus.

[0048] Figure 4 A schematic diagram showing the rotational speed in an existing square processing region with and without source replenishment.

[0049] Figure 5 This is a schematic diagram of a thin film deposition apparatus according to the present invention;

[0050] Figure 6 for Figure 5 Top cross-sectional view of the medium vacuum reaction chamber and its internal components;

[0051] Figure 7 This is a schematic diagram of a bushing structure in which the overall width of the processing area decreases according to the present invention.

[0052] Figure 8 This is a schematic diagram comparing the overall shrinkage width of the processing area of ​​the present invention with the length of the existing square processing area.

[0053] Figure 9 This is a schematic diagram comparing the rotational speed in the processing area of ​​the overall shrinkage width of the present invention under conditions of supplemented and unsuppleed sources.

[0054] Figure 10 This is a schematic diagram of a bushing structure in which the width of a partially processed area decreases according to the present invention.

[0055] Figure 11This is a schematic diagram comparing the rotational speed in a partially contracted width processing area of ​​the present invention under conditions of source replenishment and no source replenishment.

[0056] Figure 12 This is a schematic diagram of a bushing structure with a processing area width that tapers in an arc shape according to the present invention.

[0057] Figure 13 This is a schematic diagram comparing the length and speed of the processing area of ​​the arc-shaped shrinkage width of the present invention with that of the existing square processing area at various angles.

[0058] Figure 14 This is a schematic diagram comparing the rotational speed in the processing area of ​​the arc-shaped shrinkage width of the present invention under the conditions of supplemented and unsuppleed sources.

[0059] Figure 15 This is a schematic diagram of the gas flow space within a vacuum reaction chamber according to the present invention;

[0060] Figure 16 This is a schematic diagram comparing the growth rate of the dual-dimensional shrinkage processing area of ​​the present invention with that of the existing square processing area.

[0061] Figure 17 This is a schematic diagram comparing the rotational speed in the processing region of the two-dimensional shrinkage method of the present invention under the conditions of source replenishment and no source replenishment. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] It should be noted that, in this document, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." or "including..." does not exclude the presence of additional elements in the process, method, article, or terminal device that includes said element.

[0064] It should be noted that the accompanying drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clearly illustrate the purpose of the embodiments of the present invention.

[0065] like Figure 1 and Figure 2 The diagram shows a schematic of a conventional horizontal thin-film deposition apparatus. This apparatus includes a vacuum reaction chamber 100 for processing a single substrate W, including depositing material onto the upper surface of the substrate W. A rotatable tray 110 is disposed within the vacuum reaction chamber 100, located in the processing area, and includes a support surface for carrying the substrate W. In one embodiment, the tray 110 includes a transfer ring for conveying the substrate W. The vacuum reaction chamber 100 includes a reaction chamber body and a top cover 101. The reaction chamber body includes a sidewall 102 and a bottom wall 103. A transfer port 104 is provided on the sidewall 102 to facilitate the transfer of the substrate W between the inside and outside of the vacuum reaction chamber 100. An air inlet 105 (not on the same sidewall as the transfer port 104) corresponding to an air inlet assembly is also provided on the sidewall 102, and an exhaust port 106 corresponding to an exhaust assembly is provided on the bottom wall 103. The vacuum reaction chamber 100 includes an intake region corresponding to the intake opening 105, an exhaust region corresponding to the exhaust opening 106, and a processing region located between the intake region and the exhaust region. Specifically, along the direction from the intake opening 105 to the exhaust opening 106, the intake region is the area from the intake opening 105 to the front end of the tray 110, the processing region is the area from the front end of the tray 110 to the rear end of the tray 110, and the processing region has a square structure. The exhaust region is the area from the rear end of the tray 110 to the exhaust opening 106. The front end of the tray 110 is the end of the tray 110 closest to the intake opening 105, and the rear end of the tray 110 is the end of the tray 110 closest to the exhaust opening 106. Furthermore, the thin film deposition apparatus also includes a heating device for heating the tray 110 to bring the substrate W on the tray 110 to the required process temperature. On the other hand, a main MO source (metal-organic compound source) is provided at the air inlet 105. The main MO source is used to provide the raw materials required for the reaction into the vacuum reaction chamber 100 (e.g., the main MO source includes a gallium source to provide TMGA into the chamber). To further adjust the thin film growth within the chamber, the thin film deposition apparatus can also provide edge MO sources (e.g., the edge MO sources include gallium sources to provide TMGA into the chamber) on both sides of the main MO source to adjust the distribution of MO sources within the chamber. The main MO source and the two edge MO sources constitute the air inlet assembly.

[0066] During the process, the tray 110 and the substrate W are heated by a heating device to reach the process temperature, and the tray 110 is rotated to increase the uniformity of the deposited film on the substrate W. The raw materials input by the inlet assembly enter the inlet area of ​​the vacuum reaction chamber 100 in a gaseous state through the inlet opening 105 for mixing. The mixed process gas diffuses into the processing area, where the metal atoms in the process gas react chemically with other chemical substances (such as ammonia in ammonia gas), thereby forming a thin film on the surface of the substrate W.

[0067] like Figure 3 The diagram shows the growth rate distribution at different locations along the length of the cavity using the aforementioned thin film deposition apparatus (square processing area) under different process conditions (process conditions one through four). The horizontal axis represents the range of each region along the length of the cavity; region A corresponds to the air intake region, region B corresponds to the processing region (the area containing tray 110 and substrate W), and region C corresponds to the exhaust region. The vertical axis represents the growth rate (GR). As can be seen from the diagram, along the length of the cavity, the thin film growth rate differs significantly between the processing region near the air intake opening 105 (which can be referred to as its beginning) and the region near the exhaust opening 106 (which can be referred to as its end). Figure 4 As shown, this is the method of using Figure 3 The diagram illustrates the film growth rate distribution at different positions along the radial direction of substrate W under the fourth process condition and with substrate W in a rotating state, both with and without source replenishment. Since substrate W is rotating, the film growth rate along the radial direction of substrate W refers to the average growth rate at various positions on the circumference at the same distance from the center of substrate W. As shown in the rotational growth rate curve without source replenishment, even though tray 110 and substrate W are constantly rotating during the process, the significant difference in growth rate between the beginning and end of the processing area still leads to uneven film deposition along the radial direction of substrate W.

[0068] In practical applications, the above problems are usually improved by supplementing the source. Specifically, during the process, reactive raw materials are introduced into the cavity through an edge MO source to adjust the film growth rate at various locations on the substrate W. For example... Figure 4As shown, in this embodiment, the non-uniformity of the film deposited on substrate W without source replenishment is 5.2%, and the source efficiency is 20.4%; under the first source replenishment condition, the non-uniformity of the film deposited on substrate W is 1.4%, and the source efficiency is 13.8%; under the second source replenishment condition, the non-uniformity of the film deposited on substrate W is 2.2%, and the source efficiency is 11.2%. As can be seen from the above, although existing thin film deposition apparatuses can optimize the uniformity of film growth through edge MO sources, thus restoring the uniformity of growth rate on the surface of substrate W, this method leads to a significant sacrifice in source efficiency, severely damaging the source efficiency and making it difficult to achieve the optimal state for various factor indicators.

[0069] To address the aforementioned problems, this invention provides a thin film deposition apparatus. This apparatus adjusts the width of at least a portion of the processing area within the vacuum reaction chamber 200, causing the width of at least a portion of the processing area to continuously decrease. This increases the concentration of reactants in the process gas within the processing area, thereby allowing more reactants to reach the surface of the substrate W and react. This increases the thin film growth rate of the substrate W in this area, helps to improve the film growth rate at the tail end of the substrate W surface, and ultimately improves the uniformity of the thin film deposited on the substrate W surface.

[0070] Specifically, such as Figure 5 and Figure 6The diagram shows a schematic of a thin film deposition apparatus according to the present invention. This apparatus includes a vacuum reaction chamber 200 for processing a single substrate W, for example, the substrate W having a diameter of 300 mm or larger. It is worth noting that the thin film deposition apparatus proposed in this invention is not limited to processing a single substrate W, but can also be used to process multiple substrates W, for example, multiple small-sized substrates W can be arranged in the area where a single substrate W is located. The vacuum reaction chamber 200 includes a top cover 201, side walls 202, and a bottom wall 203. The side walls 202 have an air inlet 205 corresponding to the air inlet assembly 23 and a transfer port 204 for transferring wafers (the air inlet 205 and the transfer port 204 are not on the same side wall). The air inlet 205 supplies process gas into the vacuum reaction chamber 200 in a horizontal direction. The bottom wall 203 has an exhaust opening 206 corresponding to the exhaust assembly. The exhaust direction of the exhaust opening 206 is perpendicular to the gas supply direction of the intake opening 205. The vacuum reaction chamber 200 includes an intake region corresponding to the intake opening 205, an exhaust region corresponding to the exhaust opening 206, and a processing region located between the intake region and the exhaust region. The extent of the intake region, processing region, and exhaust region can be defined with reference to the methods described in existing thin film deposition apparatuses. The direction from the intake region to the exhaust region is defined as the length direction of the thin film deposition apparatus, and the direction perpendicular to the length direction in the horizontal plane is defined as the width direction of the thin film deposition apparatus. Along the path from the center of the processing region to the exhaust region, at least a portion of the width of the processing region continuously decreases along the length direction.

[0071] Furthermore, a base assembly 210 is provided within the vacuum reaction chamber 200. The base assembly 210 includes a rotatable tray 211 and a base 212. The tray 211 includes a bearing surface for supporting the substrate W, thereby placing the substrate W in the processing area. The tray 211 can be suspended and rotated under the drive of gas. The base 212 is supported by a support cylinder 213 and is located below the tray 211. The thin film deposition apparatus also includes a heating device 260 for heating the tray 211 and the substrate W. Furthermore, an air intake assembly 23 disposed at the air intake opening 205 includes a main metal-organic compound source, i.e., a main MO source 220, to provide the raw materials required for the reaction into the vacuum reaction chamber 200. The air intake assembly 23 also includes two edge metal-organic compound sources, i.e., edge MO sources 230, respectively disposed on both sides of the main MO source 220, to adjust the distribution of raw materials within the chamber.

[0072] As can be seen from the above, in this application, along the length of the thin film deposition apparatus, the width of at least a portion of the processing area shows a continuous decreasing trend. During the process, when the process gas is delivered to this continuously decreasing width area, the flow of the process gas is blocked by the structure surrounding the edge of the processing area, causing more of the process gas to flow towards the center of the substrate W, thereby increasing the concentration of the process gas in this area. This allows more process gas raw materials to reach the surface of the substrate W and react, thereby increasing the thin film growth rate of the substrate W in this area. This structure helps to improve the uniformity of material growth on the surface of the substrate W, eliminating the weakness of needing to sacrifice source efficiency to improve interface quality and thin film uniformity in square processing areas.

[0073] like Figure 5 As shown, the inlet region, the reaction region, and the exhaust region are arranged along the length direction so that the process gas enters the reaction region horizontally, thereby forming an airflow parallel to the substrate W in the reaction region. After the process gas completes the reaction in the reaction region, it, along with its byproducts and other gases, is discharged downwards from the exhaust region through the exhaust opening 206 from the vacuum reaction chamber 200.

[0074] like Figure 5 and Figure 6 As shown, the air intake area, processing area, and exhaust area are circumferentially surrounded by a bushing 240 (Shutter). The bushing 240 has an opening corresponding to the air intake opening 205 to allow the reactants to enter the vacuum reaction chamber 200. The bushing 240 is connected to a drive device. During wafer transfer, the drive device lowers the bushing 240, exposing the wafer transfer opening 204 to facilitate wafer transfer. After the substrate W is placed on the tray 211, the drive device raises the bushing 240 to surround the periphery of the substrate W and block the wafer transfer opening 204 to prevent it from affecting the process. Optionally, the bushing 240 is made of graphite material; however, it can also be made of other materials, and this invention does not limit this. In practical applications, the inner wall of the bushing 240 corresponding to at least a portion of the processing area can be processed to have a narrower width. It is understood that in this invention, the width of the inner wall of the processing area / bushing 230 shrinks symmetrically, that is, it shrinks symmetrically about the center plane along the length of the processing area, so as to ensure that both sides have the same process gas concentration enhancement effect, and thus ensure the same growth rate.

[0075] In practical applications, due to factors such as the continuous consumption of process gas on the substrate W, the concentration of process gas gradually decreases from the beginning (near the inlet area) to the end (near the outlet area) of the processing region, resulting in a greater film growth rate at the beginning of the processing region than at the end. Based on this, the present invention allows the width of the processing region at the end to continuously decrease. For example... Figure 6As shown, in one embodiment, the end of the processing area near the air inlet 205 is its first end, and the end of the processing area near the exhaust outlet 206 is its second end. The width of the second end of the processing area continuously decreases, and the width of the first end of the processing area is greater than the width of its second end. Based on the above method, the tail end of the processing area is divided into a width-contracting form, that is, the inner wall of the bushing 240 in this area is in a width-contracting form. Compared with a square processing area, this structure can increase the concentration of process gas at the tail end of the processing area, thereby increasing the material growth rate in this area to balance the growth rate distribution throughout the entire surface of the substrate W. This can significantly reduce the need for supplementary source through the edge MO source 230 during the process. Based on this structure, in practical applications, even if there is a need for supplementary source, only a small flow of supplementary source from the edge MO source 230 is required to achieve optimal synergy of all indicators, avoiding the sacrifice of source efficiency to balance the growth rate of each area on the surface of the substrate W.

[0076] Furthermore, the width of at least a portion of the exhaust region can exhibit a continuously decreasing trend. The first end of the exhaust region is defined as the end closest to the processing region, and the last end as the end closest to the exhaust opening 206. In practical applications, when the width of the last end region of the processing region exhibits a continuously decreasing trend, the width of at least the first end region of the exhaust region can also exhibit a continuously decreasing trend. Preferably, this decreasing trend is continuous with the decreasing trend of the processing region. For example, such as... Figure 6 As shown, in this embodiment, the width of the processing area decreases with the same linear slope as the width of the exhaust area. This method simplifies the machining of the bushing 240 and also helps reduce turbulence within the cavity. Of course, the width of the exhaust area is not limited to the above form. In practical applications, the width of the exhaust area can also be set to be the same, and this invention does not impose any limitations on this.

[0077] In practical applications, the outer edge contour of the base 212 is typically machined based on the inner wall contour of the bushing 240, and the tail end position of the base 212 (the end near the exhaust opening 206) is basically the same as the tail end position of the processing area. In existing thin film deposition apparatuses, the inner wall of the bushing 240 and the outer edge of the base 212 are usually square contours, and the apex region of the tail end of the base 212 is usually a right angle, which easily accumulates stress, resulting in high stress in the apex region of its tail end, which can easily lead to cracking of the base 212. However, in this invention, when the inner wall of the tail end portion of the bushing 240 is in a width-contracting form, the tail end region of the base 212 can also be in a width-contracting form, that is, the width of its tail end region shows a continuous decreasing trend. This method can reduce stress accumulation in this area, thereby effectively reducing the stress in the apex region of the tail end of the base 212, and greatly reducing the probability of cracking.

[0078] To further balance factors such as uniformity of the processing speed and source efficiency, in practical applications, the position where the width of the processing area begins to shrink can be set. Specifically, the length of the processing area in the longitudinal direction is set to L. Along the direction from the intake area to the exhaust area, the width of the area from the first position of the processing area to its tail end shows a continuous decreasing trend. The distance between the projection of the first position in the longitudinal direction and the projection of the tail end of the processing area in the longitudinal direction is greater than or equal to 1 / 10L. Based on this method, the process gas in the tail end region of the processing area can have a sufficient concentration, thereby increasing the material growth rate in this region to the expected level and ensuring the source replenishment effect on the tail end region of the substrate W.

[0079] In some embodiments, the first position may coincide with the beginning position of the processing region. Further, by setting the beginning of the air intake region to be the end closest to the air intake opening 205 and its end closest to the processing region, the width of at least the end region of the air intake region can continuously decrease. Preferably, this decreasing trend is continuous with the decreasing trend at the beginning of the processing region. Of course, the width of the air intake region is not limited to the above form; in practical applications, the width of the air intake region can also be set to be the same, and this invention does not limit this. It should be noted that in the thin film deposition apparatus of this invention, the width of the air intake region is preferably not increasing along the length direction to avoid turbulence (especially in the beginning region of the processing region). The width of the exhaust region is preferably not increasing to avoid slowing down the airflow velocity, causing thermal buoyancy to affect the flow field, and resulting in uneven thin film deposition. Based on the above, in the width direction, the minimum width of the air intake region is not less than the maximum width of the processing region, and the minimum width of the processing region is not less than the maximum width of the exhaust region.

[0080] For example, such as Figure 7 As shown, in one embodiment, the inner wall width of the bushing 240 begins to shrink from the inlet area and ends at the outlet area. The width reduction trend of the inlet area, processing area, and outlet area is continuous (decreasing with the same linear slope), meaning the entire inner wall width of the bushing 240 decreases progressively. Based on this structure, the inlet area provides sufficient mixing and preheating space for the process gas, allowing it to be fully mixed and preheated before entering the processing area. After entering the processing area, the process gas concentration is significantly increased (compared to a square processing area) due to the continuous shrinkage of the inner wall width of the bushing 240. This allows more process gas raw materials to reach the substrate surface and participate in film growth, increasing the film growth rate in the processing area and contributing to the control of film growth uniformity on the substrate surface. Furthermore, in this embodiment, the bushing 240 is easy to process, helping to ensure its processing accuracy. Figure 8The diagram shows a comparison of the growth rates along the cavity length direction in the width-shrinking processing region of this embodiment and the existing square processing region. As can be seen from the diagram, the film growth rate at the tail end of the width-shrinking processing region in this embodiment is increased by 25% compared to the tail end of the existing square processing region. Based on this width-shrinking processing region, the difference in film growth rates between the beginning and end of the processing region can be further reduced by adjusting the process conditions, thereby improving the uniformity of the growth rate distribution on the substrate W surface. Alternatively, the uniformity of the growth rate distribution on the substrate W surface can also be improved by performing source compensation processing on the process. Figure 9 The figure shows a comparison of the rotational speed along the radial direction of substrate W in the processed region with and without source supplementation (substrate W is rotating). As can be seen from the figure, with edge MO source 230 supplementation, the non-uniformity of the film deposited in the processed region with linearly narrowed width is 2.2%, while its source efficiency can still be maintained at 20.1%, compared to... Figure 4 The comparison shows that the reduced width of the processing area eliminates the weakness of the square processing area requiring the sacrifice of source efficiency to improve interface quality, and significantly reduces the need for source replenishment through the edge MO source 230 during the process.

[0081] On the other hand, the first position may not coincide with the beginning of the processing area. In practical applications, the position of the first position can be selected from the area from the center of the processing area to the end of the processing area (including the center of the processing area), and the selection range of the first position where shrinkage begins is from the center of the processing area to a distance of 2 / 5L along the length direction from the center. This method can compensate for the film growth rate at the corresponding position of the processing area by increasing the concentration of process gas, while avoiding sacrificing source efficiency.

[0082] For example, such as Figure 10 As shown, in one embodiment, the inner wall width of the bushing 240 narrows from a first position in the processing region to the tail end of the venting region. This first position is 1 / 4L long from the center of the processing region, i.e., the center of the substrate W. Based on this structure, the film growth rate in the region adjacent to the tail end of the processing region can be further guaranteed while ensuring the film growth rate in the region adjacent to the tail end of the processing region. Figure 11 The figure shows a comparative diagram of the rotational speed along the radial direction of substrate W with and without source replenishment in the shrinkage treatment area (substrate W is rotating). As can be seen from the figure, with the edge MO source 230 replenishing the source, the non-uniformity of the film deposited in this shrinkage treatment area is 0.7%, while its source efficiency is 18%, compared to... Figure 4The comparison shows that this shrinkage processing area eliminates the weakness of the square processing area, which requires sacrificing source efficiency to improve interface quality. Based on this shrinkage processing area, the uniformity of film growth rate can be improved while ensuring source efficiency.

[0083] Understandably, in practical applications, the width of the processing area can be reduced from a certain position between the center of the processing area and the intake area. In practical applications, this setting can be selected according to the actual situation.

[0084] On the other hand, the inventors noted during the research and development process that, preferably, when the width of the processing area shrinks, setting a sufficient distance between the inner wall of the bushing 240 and the edge of the target deposition area can prevent the inner wall of the bushing 240 from affecting the thin film growth at the edge of the substrate W (avoiding unnecessary losses due to some process gas deposition on the inner wall of the bushing 240). The outline and size of the target deposition area are the same as the outline and size of the substrate W. When the thin film deposition apparatus is used to process multiple substrates W, the outline and size of its target deposition area are approximately the same as those of the target deposition area in a single-wafer thin film deposition apparatus. Optionally, the shortest distance between the inner wall of the bushing 240 and the edge of the target deposition area, i.e., the edge of the substrate W, is greater than or equal to 10 mm. In practical applications, when the distance between the inner wall of the bushing 240 and the edge of the target deposition area is less than this shortest distance, it will affect the growth rate of the substrate W edge, resulting in uneven growth rate on the substrate W surface.

[0085] On the other hand, the present invention does not limit the manner in which the width of the processing area is reduced. Optionally, along the path from the center of the processing area to the exhaust area, at least a portion of the width of the processing area decreases linearly (see [reference]). Figure 7 or Figure 10 Based on this method, the film growth rate in the region with reduced processing area width can be increased, which helps to improve the uniformity of film growth on the substrate W surface. For example, such as Figure 10 As shown, in this embodiment, the width of the tail region of the processing area decreases linearly. In this embodiment, the non-uniformity of the film deposited in the linearly shrinking processing area is 0.7%, while its source efficiency is 18%. Compared with the existing square processing area, this linearly shrinking processing area can ensure the uniformity of film growth rate while ensuring source efficiency, and significantly reduces the need for source replenishment through the edge MO source 230 during the process.

[0086] The width of the processing area of ​​the present invention can also decrease non-linearly. Optionally, along the path from the center of the processing area to the exhaust area, the width of at least a portion of the processing area continuously decreases in an arc shape. In this manner, the angle between the tangent of the edge of the processing area and the tangent of the edge of the substrate W at this point can be continuously adjusted so that the edge contour of the processing area approaches the contour of the edge of the substrate W.

[0087] Furthermore, the arc shape can be a circular arc, meaning the curvature is the same at all points along the arc, to facilitate the machining of the bushing 240. Preferably, as shown below... Figure 12 As shown, the curvature of the arc shape is the same as that of the substrate W, and the angle between the tangent of the edge of the arc portion of the processing area and the tangent of the edge of the substrate W at this point is 0° (i.e., they are parallel). Based on this structure, in areas where the width of the processing area varies, the distance between the inner wall of the bushing 240 and the edge of the substrate W is equal, which helps to improve the uniformity of the film growth rate at the edge of the substrate W, improve the controllability of the process, and thus improve the film growth quality. On the other hand, this method minimizes the space occupied between the inner wall of the bushing 240 and the edge of the substrate W, which helps to save space.

[0088] like Figure 13 The diagram shows a comparison of the growth rates at various angles between the arc-shaped shrinkage width processing area and the existing square processing area in one embodiment of the present invention. The transfer port 204 is at 0°, the air inlet 205 is at 90°, and the exhaust port 206 is at -90°. As can be seen from the diagram, compared to the existing square processing area, the arc-shaped shrinkage width processing area can significantly improve the film growth rate on the side of the processing area near the exhaust port 206. Furthermore, as... Figure 14 The diagram shows a comparison of the rotational speed along the radial direction of the substrate W in the processing area with and without source replenishment in the case of the arc-shaped shrinkage width (the substrate W is in a rotating state). In this embodiment, under source replenishment condition, the non-uniformity of the film deposited on the substrate W is 0.9%, and the source efficiency is 19.5%. Figure 4 and Figure 14 The comparison shows that, compared to the existing square processing area, this arc-shaped shrinkage width processing area can ensure the uniformity of film growth rate while maintaining source efficiency. On the other hand, due to... Figure 11 and Figure 14 The comparison shows that, compared with linear shrinkage, the arc-shaped shrinkage method can maintain the non-uniformity of the film deposited on the substrate W while improving source efficiency.

[0089] On the other hand, in this invention, the growth state of the substrate W surface can also be improved by modifying the height of the processing area, wherein the height of the processing area is the distance between the plane containing the bearing surface and the top inner wall of the vacuum reaction chamber 200. Specifically, along the length direction, the height of at least a portion of the processing area decreases, that is, the height of at least a portion of the processing area is in a contracting form (see [link to related document]). Figure 5 or Figure 15 As mentioned above, in this application, the process gas enters the processing area in a horizontal manner. The reduced height of the processing area allows some of the process gas to have a downward velocity, increasing the amount of downward mass flow of the process gas, which helps to improve the film growth rate in this area and achieve the effect of increasing the growth rate. This avoids improving the growth rate uniformity and interface quality by sacrificing source efficiency.

[0090] Preferably, the width contraction region and the height contraction region of the processing area at least partially overlap. Based on this structure, when the process gas enters the processing area, not only can the concentration of the process gas in the area be increased under the effect of the width contraction, but the amount of downward mass flow of the process gas can also be increased under the effect of the height contraction. At the same time, due to the width contraction, the downward convection effect of the process gas above the substrate W can be further enhanced, which helps to improve the long-term uniformity and interface quality in the process.

[0091] For example, such as Figure 15 As shown, in one embodiment, the overall width of the processing area is... Figure 12 The embodiment exhibits a decreasing trend (circular contraction) while the overall height of the processing area also decreases, creating a two-dimensionally contracting processing area. For example... Figure 16 The diagram shows a comparison of the growth rate of the dual-dimensional shrinkage processing area and the existing square processing area along the length of the cavity. As can be seen from the diagram, the dual-dimensional shrinkage processing area can effectively improve the film growth rate across the entire processing area, especially at the tail end of the processing area, which helps to improve the uniformity of film growth rate on the substrate W surface. Furthermore, as... Figure 17 The diagram shows a comparison of rotational speeds between the processed region with and without source replenishment using this dual-dimensional shrinkage method (substrate W is in a rotating state). In this embodiment, in the unreplenished state, the non-uniformity of the film deposited on substrate W is 7.5%, and the source efficiency is 25.2%; in the replenished state, the non-uniformity of the film deposited on substrate W is 0.9%, and the source efficiency is 22%. Figure 4 and Figure 17 It can be seen that, compared to the existing square processing area, this two-dimensional shrinkage processing area can significantly improve the source efficiency in the process. On the other hand, due to... Figure 11 , Figure 14 and Figure 17The comparison shows that the two-dimensional contraction method is more effective at preventing source effect loss than the one-dimensional contraction method.

[0092] Optionally, along the length direction, the height of at least a portion of the processing area decreases linearly. For example, as... Figure 15 As shown, the end of the processing area closest to the air inlet 205 is its first end, and the end of the processing area closest to the exhaust outlet 206 is its second end. The height of the entire processing area decreases linearly, and the height of the first end is greater than the height of the second end. In this embodiment, the height of the entire processing area decreases linearly, and the angle between the top boundary of the processing area and the horizontal plane is constant. This results in a uniform downward acceleration effect on the process gas flow, helping to ensure the uniformity of the process gas velocity reaching the substrate W. Of course, the method of decreasing the height of the processing area is not limited to the above; in other embodiments, it can also be a non-linear decrease. Optionally, the non-linear trend can be a convex curve shape or a concave curve shape.

[0093] like Figure 5 As shown, in one embodiment, the top of the processing area is a top plate structure 250. Along the length direction, the distance between the bottom wall of the top plate structure 250 and the plane containing the bearing surface decreases. The inner wall of the bushing 240 and the inner wall of the top plate structure 250 together form the boundary between the air intake area, the processing area, and the exhaust area. Optionally, the top plate structure 250 can be made of graphite material, but it can also be made of other materials; this invention does not limit this. In practical applications, at least a portion of the inner wall of the top plate structure 250 can be processed and improved so that the distance between the inner wall of the top plate structure 250 and the bearing surface decreases linearly or non-linearly, and the shape of its outer wall is not limited.

[0094] Optionally, the ratio between the reduced height of the top plate structure and the length of the processing area is between 1 and 1.5, meaning the area with reduced top plate structure height must at least cover the entire substrate W to improve the film growth rate on the entire substrate W. If the ratio is greater than 1.5, it will lead to excessive deposits in the air intake area, resulting in increased contaminants in the chamber, a shorter chamber cleaning cycle, and reduced source efficiency.

[0095] Alternatively, the height of the boundary between the processing area and the intake area can be set to L2, and the minimum height of the processing area can be set to L1 (see [link to relevant documentation]). Figure 15The value of L2 / L1 is greater than 1 and less than or equal to 5. When the ratio of the two is greater than 5, it will cause a decrease in long-term speed and a reduction in source efficiency. In practical applications, in order to facilitate chip transfer, the processing area needs to have a sufficient minimum height. Optionally, the minimum height of the processing area is greater than or equal to 10mm.

[0096] In summary, in the thin film deposition apparatus of the present invention, by adjusting the width of at least a portion of the processing area within the vacuum reaction chamber 200, the width of at least a portion of the processing area shows a continuous decreasing trend, thereby increasing the density of the process gas in the area. This allows more reactants to reach the surface of the substrate W and react, increasing the thin film growth rate of the substrate W in that area. This structure helps to improve the uniformity of the thin film growth rate on the surface of the substrate W, eliminating the weakness of requiring sacrifice of source efficiency to improve interface quality and thin film uniformity in square processing areas.

[0097] Furthermore, the device can further adjust the height of the processing area so that the height of at least part of the processing area tends to decrease, thereby giving the process gas a downward velocity and increasing the amount of downward mass flow of the process gas, which helps to improve the film growth rate of the substrate W in this area.

[0098] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A thin film deposition apparatus, characterized in that, Include: A vacuum reaction chamber having an inlet opening and an outlet opening, wherein the inlet opening is used to supply process gas into the vacuum reaction chamber in a horizontal direction; A base assembly disposed within the vacuum reaction chamber, the base assembly including a bearing surface for supporting a substrate; The vacuum reaction chamber includes an air intake area corresponding to the air intake opening, an exhaust area corresponding to the exhaust opening, and a processing area located between the air intake area and the exhaust area. The direction from the air intake area to the exhaust area is defined as the length direction of the thin film deposition apparatus, and the direction perpendicular to the length direction in the horizontal plane is defined as the width direction of the thin film deposition apparatus. Along the path from the center of the processing area to the exhaust area, at least a portion of the width of the processing area shows a continuous decreasing trend along the length direction.

2. The thin film deposition apparatus as described in claim 1, characterized in that, The first end of the processing area is defined as the end near the air intake area, and the last end is defined as the end near the exhaust area. The width of the last end of the processing area shows a continuous decreasing trend.

3. The thin film deposition apparatus as described in claim 2, characterized in that, The length of the processing area in the longitudinal direction is set to L. Along the direction from the intake area to the exhaust area, the width of the area between the first position of the processing area and its tail end has a continuous decreasing trend. The distance between the projection of the first position in the longitudinal direction and the projection of the tail end of the processing area in the longitudinal direction is greater than or equal to 1 / 10L.

4. The thin film deposition apparatus as described in claim 3, characterized in that, The first position coincides with the beginning position of the processing area.

5. The thin film deposition apparatus as described in claim 3, characterized in that, The first position does not coincide with the beginning position of the processing area.

6. The thin film deposition apparatus as described in claim 5, characterized in that, The first position is set within a range from the center of the processing area to a distance of 2 / 5L along the length direction from the center.

7. The thin film deposition apparatus as claimed in claim 4, characterized in that, The first end of the air intake region is defined as the end closest to the air intake opening, and the last end is defined as the end closest to the processing region. The width of at least the last end of the air intake region shows a continuous decreasing trend.

8. The thin film deposition apparatus as claimed in claim 1, characterized in that, The widths of the air intake areas are all the same.

9. The thin film deposition apparatus as claimed in claim 2, characterized in that, The first end of the exhaust region is defined as the end closest to the processing region, and the last end is defined as the end closest to the exhaust opening. The width of at least the first end of the exhaust region shows a continuous decreasing trend.

10. The thin film deposition apparatus as claimed in claim 1, characterized in that, The widths of the exhaust regions are the same.

11. The thin film deposition apparatus as claimed in claim 1, characterized in that, In the width direction, the minimum width of the intake area is not less than the maximum width of the processing area, and the minimum width of the processing area is not less than the maximum width of the exhaust area.

12. The thin film deposition apparatus as claimed in claim 1, characterized in that, Along the path from the center of the processing area to the exhaust area, the width of at least a portion of the processing area decreases linearly or non-linearly.

13. The thin film deposition apparatus as claimed in claim 1, characterized in that, Along the path from the center of the processing area to the exhaust area, the width of at least a portion of the processing area decreases continuously in an arc shape.

14. The thin film deposition apparatus as claimed in claim 13, characterized in that, The arc shape is a circular arc shape.

15. The thin film deposition apparatus as claimed in claim 14, characterized in that, The curvature of the arc shape is the same as the curvature of the substrate.

16. The thin film deposition apparatus according to any one of claims 1-15, characterized in that, Along the length direction, the height of at least a portion of the processing area decreases, wherein the height of the processing area is the distance between the plane containing the bearing surface and the top inner wall of the vacuum reaction chamber.

17. The thin film deposition apparatus as claimed in claim 16, characterized in that, Along the length direction, the height of at least a portion of the processing area decreases either linearly or non-linearly.

18. The thin film deposition apparatus as claimed in claim 17, characterized in that, The nonlinear trend is either a convex curve shape or a concave curve shape.

19. The thin film deposition apparatus as claimed in claim 16, characterized in that, The height of the boundary between the processing area and the intake area is set as L2, the minimum height of the processing area is L1, and the value of L2 / L1 is greater than 1 and less than or equal to 5.

20. The thin film deposition apparatus as claimed in claim 1, characterized in that, The intake area, the processing area, and the exhaust area are surrounded circumferentially by bushings.

21. The thin film deposition apparatus as claimed in claim 20, characterized in that, The shortest distance between the inner wall of the bushing and the edge of the substrate is greater than or equal to 10 mm.

22. The thin film deposition apparatus as claimed in claim 1, characterized in that, The top of the processing area is a top plate structure, and along the length direction, the distance between the bottom wall of the top plate structure and the plane where the bearing surface is located in the processing area decreases.

23. The thin film deposition apparatus as claimed in claim 22, characterized in that, The length of the region where the height of the top plate structure decreases is 1 to 1.5 times the length of the processing region.

24. The thin film deposition apparatus as claimed in claim 1, characterized in that, Also includes: An intake assembly is disposed at the intake opening, the intake assembly comprising a main metal-organic compound source and two peripheral metal-organic compound sources, the two peripheral metal-organic compound sources being located on either side of the main metal-organic compound source.

25. The thin film deposition apparatus as claimed in claim 1, characterized in that, The base assembly includes a base, the end of which near the exhaust opening is its tail end, and the width of the tail end region of the base continuously decreases.

26. The thin film deposition apparatus as claimed in claim 1, characterized in that, The exhaust direction of the exhaust port is perpendicular to the air supply direction of the air inlet port.

27. The thin film deposition apparatus as claimed in claim 1, characterized in that, The thin film deposition apparatus is a monolithic thin film deposition apparatus.

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