A heating device and a vapour deposition apparatus

Abstract

This invention provides a heating device applied in a vapor deposition (VDC) apparatus. The VDC apparatus has a tray for supporting a wafer within its reaction chamber. The heating device is located below the tray and includes a main heating coil and a supplementary heating coil arranged at intervals in a horizontal direction. At least a portion of the main heating coil and the supplementary heating coil are located directly below the wafer edge region. Horizontally, the wafer center is located between the winding center of the main heating coil and the winding center of the supplementary heating coil. The advantages of this invention are: the supplementary heating coil effectively compensates for the insufficient heating capacity of the main heating coil to the wafer edge region, significantly improving the uniformity of wafer temperature distribution and the uniformity of the thin film thickness on the wafer surface.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a heating device and a vapor deposition apparatus. Background Technology

[0002] CVD (Chemical Vapor Deposition) refers to the process by which reactants undergo a chemical reaction on the surface of a wafer under gaseous conditions to form a thin film. CVD equipment is specifically designed for this purpose. MOCVD (Metal-organic Chemical Vapor Deposition) equipment, as a typical type of CVD equipment, provides the necessary temperature, pressure, and chemical gas composition for growing semiconductor thin films, such as GaN (gallium nitride), on wafer surfaces.

[0003] In the MOCVD process, the wafers to be processed on the tray typically need to be heated to a set temperature. Currently, most methods use induction coils to heat the tray through electromagnetic induction, and the tray then transfers the heat to the wafer to achieve this heating.

[0004] To ensure the production of high-quality thin films, a key parameter is wafer temperature. Because reactive gases react and deposit on the wafer at specific temperatures, wafer temperature is one of the key factors affecting the material deposition rate on the wafer. Inconsistent wafer surface temperatures lead to uneven film deposition, resulting in inconsistent physical properties of the film and consequently affecting the performance of integrated circuit devices manufactured from the wafer.

[0005] For circular, monolithic wafer trays (which can only hold one wafer at a time), a flat, circularly wound induction coil is typically placed beneath the tray (the center of the induction coil corresponds to the center of the tray). This type of induction coil has insufficient heating capacity for the central area of ​​the tray, resulting in a lower temperature in that area. Uneven tray temperature leads to uneven wafer temperature distribution, which in turn affects the quality of the thin film on the wafer.

[0006] Improving the uniformity of wafer temperature distribution is a pressing issue that needs to be addressed when using induction coil heating trays. Summary of the Invention

[0007] The purpose of this invention is to provide a heating device and a vapor deposition apparatus. The heating device includes a main heating coil and a supplementary heating coil. The center of the wafer and the winding center of the main heating coil are eccentrically arranged to avoid insufficient heating of the central area of ​​the wafer by the main heating coil. The supplementary heating coil provides supplementary heating to the edge area of ​​the wafer, effectively improving the uniformity of the wafer temperature distribution and achieving the growth of a thin film with uniform thickness on the wafer surface.

[0008] To achieve the above objectives, the present invention provides a heating device applied in a vapor deposition apparatus. The vapor deposition apparatus has a tray for supporting wafers inside its reaction chamber. The heating device is located below the tray and includes a main heating coil and a supplementary heating coil arranged at intervals in the horizontal direction.

[0009] At least a portion of the main heating coil and the supplementary heating coil are located directly below the wafer edge region;

[0010] In the horizontal direction, the wafer center is located between the winding center of the main heating coil and the winding center of the supplementary heating coil.

[0011] Optionally, the horizontal distance between the wafer center and the winding center of the main heating coil and the winding center of the supplementary heating coil are not equal.

[0012] Optionally, the winding center of the main heating coil is located inside the wafer edge, and the winding center of the supplementary heating coil is located outside the wafer edge.

[0013] Optionally, the heating power of at least one of the main heating coil and the supplementary heating coil is adjustable.

[0014] Optionally, the alternating currents in the main heating coil and the supplementary heating coil have the same frequency and phase.

[0015] Optionally, both the main heating coil and the supplementary heating coil are wound in a rectangular shape; adjacent sections of the main heating coil and the supplementary heating coil are parallel to each other.

[0016] Optionally, the tray has a rectangular structure, with the long side of the tray pointing in the direction of the flow of the reaction gas in the reaction chamber; each section of the main heating coil and the supplementary heating coil is parallel to the long or short side of the tray.

[0017] Optionally, at least one apex corner of the tray has a chamfered structure.

[0018] Optionally, the outermost turns of both the main heating coil and the supplementary heating coil are located on the outside of the wafer.

[0019] Optionally, the reaction chamber is provided with a gas injection port and a gas exhaust port on opposite sides; the main heating coil is close to the gas injection port and the supplementary heating coil is close to the gas exhaust port; or, the main heating coil is close to the gas exhaust port and the supplementary heating coil is close to the gas injection port.

[0020] Optionally, in the direction of gas flow, the main heating coil or supplementary heating coil near the gas injection port has a minimum turn pitch at a position located at the front end of the wafer.

[0021] Optionally, in the direction of gas flow, the distance between the wafer and the short side of the tray near the gas injection port is greater than the distance between the wafer and the short side of the tray near the gas discharge port.

[0022] Optionally, the spacing between adjacent sections of the main heating coil and the supplementary heating coil is...

[0023] Optionally, the maximum segment length of the main heating coil is L1 along the short side of the tray; the maximum segment length of the main heating coil is L2 along the long side of the tray; let d represent the wafer diameter, 0.5 <d / L1<1,0.6<d / L2<1.2。

[0024] Optionally, the height of any section on the main heating coil and / or supplementary heating coil is adjustable.

[0025] The present invention also provides a vapor deposition apparatus, comprising:

[0026] The reaction chamber contains a tray, on which a wafer carrier disk for supporting wafers is mounted; the wafer carrier disk is rotatable around its own center.

[0027] The heating device as described in this invention is disposed below the tray.

[0028] Optionally, the vapor deposition apparatus further includes at least one of a first current regulation circuit and a second current regulation circuit; the first current regulation circuit and the second current regulation circuit are used to independently regulate the heating power of the main heating coil and the supplementary heating coil, and to make the currents in adjacent sections of the main heating coil and the supplementary heating coil in the same frequency and phase.

[0029] Optionally, the tray is also provided with a cover plate, which surrounds the outer periphery of the wafer carrier disk.

[0030] Optionally, a portion of the main heating coil and a portion of the supplementary heating coil are located directly below the cover plate.

[0031] Optionally, it also includes a loading ring; the loading ring is disposed around the outer periphery of the wafer and located between the wafer and the cover plate; the inner edge of the upper surface of the loading ring has a step, the edge of the wafer extends above the step, and the lower surface of the loading ring has a groove for accommodating a robot arm.

[0032] Optionally, the reaction chamber is provided with a gas injection port and a gas exhaust port on opposite sides; the gas injection port is located on the side wall of the reaction chamber, and the gas exhaust port is located on the bottom wall of the reaction chamber; the vapor deposition apparatus also includes a guide plate located downstream of the tray; the top of the guide plate has a downward sloping surface, through which the gas in the reaction chamber is guided to the gas exhaust port.

[0033] Optionally, the vapor deposition apparatus further includes a protective cover disposed below the tray; the heating device is disposed inside the protective cover, and the protective cover prevents the heating device from being corroded by the gas in the reaction chamber.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1) The heating device and vapor deposition equipment of the present invention use a main heating coil and a supplementary heating coil to heat the wafer. The center of the wafer is eccentrically arranged relative to the winding center of the main heating coil and the winding center of the supplementary heating coil. The supplementary heating coil effectively compensates for the insufficient heating capacity of the main heating coil to the edge area of ​​the wafer, which significantly improves the uniformity of the wafer temperature distribution and the uniformity of the thin film thickness on the wafer surface.

[0036] 2) In this invention, both the main heating coil and the supplementary heating coil are rectangularly wound, and the adjacent sections of the main heating coil and the supplementary heating coil are parallel to each other, which helps to uniformly heat the tray area between the main heating coil and the supplementary heating coil and improve the consistency of wafer temperature.

[0037] 3) The alternating current frequencies in the main heating coil and the supplementary heating coil are the same, and the alternating current phases in adjacent sections of the main heating coil and the supplementary heating coil are the same. This can avoid mutual interference between the main heating coil and the supplementary heating coil, enhance the alternating magnetic field between the main heating coil and the supplementary heating coil, and improve the heating efficiency of the tray area between the main heating coil and the supplementary heating coil.

[0038] 4) The heat dissipation environment at the edge of the tray is relatively good, which can easily lead to a lower temperature in the area of ​​the tray edge. In this invention, a rectangular tray is used, and the outermost turns of the main heating coil and the supplementary heating coil are located on the outer periphery of the wafer, so that the area of ​​the heated area of ​​the tray is larger than the area of ​​the wafer. This can effectively avoid uneven radial temperature distribution of the wafer caused by a lower temperature at the edge of the tray.

[0039] 5) The rectangular tray extends the preheating distance before the reactive gas reaches the wafer surface, and the main heating coil (or supplementary heating coil) has the smallest turn pitch at the closest point to the gas injection port, which improves the preheating efficiency of the reactive gas and helps to preheat the reactive gas to the required temperature. This greatly improves the utilization rate of the reactive gas in the reaction chamber (also known as improved source efficiency) and the deposition quality of the thin film on the wafer surface.

[0040] 6) The spacing between the wafer and the short side of the tray near the gas injection port is greater than the spacing between the wafer and the short side of the tray near the gas exhaust port. This not only helps to fully preheat the reaction gas but also prevents excessive deposition of the reaction gas downstream of the wafer.

[0041] 7) Because of the thermal stress concentration at the top corner of the pallet, the top corner of the pallet in this invention adopts a chamfered structure, which can greatly reduce the probability of pallet cracking.

[0042] 8) In this invention, the turn spacing of the main heating coil and the supplementary heating coil is set reasonably, which not only improves the heating efficiency of the tray, but also avoids the occurrence of arc discharge due to excessively small turn spacing. This invention can also adjust the height of corresponding sections of the main heating coil and the supplementary heating coil according to the film growth rate of each region on the wafer surface, so as to adjust the wafer temperature in different regions and thus improve the consistency of the film growth rate on the wafer surface.

[0043] 9) The present invention places the heating device inside the protective cover, which can prevent the heating device from being corroded by the reaction gas and greatly extend the service life of the heating device. 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 a vapor deposition apparatus.

[0046] Figure 2 for Figure 1 A schematic diagram of the induction coil in the diagram;

[0047] Figure 3 This is a schematic diagram of a vapor deposition apparatus in an embodiment of the present invention;

[0048] Figure 4 This is a top view of the tray in an embodiment of the present invention;

[0049] Figure 5 This is a schematic diagram of the heating device in an embodiment of the present invention;

[0050] Figure 6 This is a top view of the wafer, tray, and heating device in an embodiment of the present invention;

[0051] Figure 7 This is a top view of the wafer, tray, and heating device in another embodiment of the present invention. Detailed Implementation

[0052] 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, and 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.

[0053] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0054] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0055] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0056] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrases "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0057] Furthermore, in the description of this application, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0058] Figure 1 The diagram shows a schematic of a vapor deposition apparatus 1, which is a monolithic vapor deposition apparatus (processing one wafer W at a time), including a reaction chamber 10. The reaction chamber 10 is enclosed by a side wall 102, a chamber cover 101, and a bottom wall 103.

[0059] A gas injection port 104 is located on one side of the reaction chamber 10, and a gas outlet 105 is located on the opposite side of the reaction chamber 10, opposite to the gas injection port 104. The reaction gas used for deposition flows into the reaction chamber 10 from the gas injection port 104, and then flows above the surface of the wafer W, achieving the deposition of a thin film on the surface of the wafer W. Finally, the reaction gas that has not yet reacted and the reaction byproducts flow out of the reaction chamber 10 through the gas outlet 105.

[0060] like Figure 1 As shown, the reaction chamber 10 contains a circular, single-piece tray 120 (carrying one wafer W at a time). The upper surface of the tray 120 has a recess for accommodating a wafer carrier 130, on which the wafer W is placed. This recess contains a special gas channel. Gas at a certain pressure is introduced into the gas channel through the airflow channel 121 within the tray 120, causing the wafer carrier 130 to be lifted by the gas pressure and detached from the surface of the tray 120. It then suspends at a certain height and rotates around its center (i.e., air-floating rotation), ensuring that different types of reactive gases are uniformly distributed and deposited on the wafer W. The reactive gases react at a specific temperature and deposit on the wafer W to form a thin film of the desired material. The temperature of the wafer W surface determines the material deposition rate.

[0061] Tray 120 and wafer carrier tray 130 are typically made of materials such as graphite or silicon carbide, which have good thermal conductivity. A heating device is located beneath tray 120. This heating device typically uses an induction coil 160, which offers advantages such as high efficiency, rapid heating, sensitive temperature regulation, low maintenance costs, and suitability for high-temperature conditions. The heating principle of the induction coil 160 is as follows: an alternating magnetic field is generated in space by the alternating current within the induction coil 160. An induced electromotive force is generated in tray 120 within this alternating magnetic field, thereby forming eddy currents within tray 120, which in turn heats up the tray 120. The heat generated by tray 120 is transferred to wafer W through wafer carrier tray 130, bringing wafer W to the required process temperature.

[0062] like Figure 1 As shown, the tray 120 is radially divided into a central area 120a, a middle area 120b, and an edge area 120c, with the induction coil 160 located directly below the tray 120. Figure 2As shown, the induction coil 160 is coiled in a circular shape. The space 161 enclosed by the innermost coil of the induction coil 160 corresponds to the central region 120a of the tray. The dashed arrow indicates the direction of the current in the innermost coil of the induction coil 160. The magnetic field generated by the induction coil 160 is distributed in a ring shape and is perpendicular to the plane in which the induction coil 160 is located. The magnetic field strength in the central region 120a of the tray corresponding to space 161 is relatively weak, resulting in insufficient heating of the central region 120a. The temperature of the central region 120a of the tray is lower than the temperature of the middle region 120b of the tray.

[0063] On the other hand, the heat from the edge region 120c of the tray can be directly dissipated into the surrounding space, so the temperature of the edge region 120c is lower than that of the center region 120b of the tray. The uneven temperature distribution of the tray leads to poor temperature uniformity of the wafer, and the thin film growth rate is inconsistent in different regions of the wafer W. As a result, the thin film thickness on the surface of the wafer W is uneven, and the semiconductor chips manufactured using this wafer W are of low quality.

[0064] This invention provides a heating device and a vapor deposition apparatus. The heating device includes a main heating coil and a supplementary heating coil. The supplementary heating coil compensates for areas where the main heating coil is insufficient, effectively improving the uniformity of wafer temperature distribution and enabling the growth of a thin film with uniform thickness on the surface of wafer W.

[0065] Figure 3 A vapor deposition apparatus 2 according to an embodiment of the present invention is shown, which includes a reaction chamber 20. In this embodiment, the reaction chamber 20 has a rectangular structure and is enclosed by a chamber cover 201, side walls 202 and a bottom wall 203.

[0066] like Figure 3 As shown, the gas injection port 204 is located on one side of the reaction chamber 20, and the gas discharge port 205 is located on the other side of the reaction chamber 20 opposite to the gas injection port 204. Figure 3 The gas outlet 205 is located on the bottom wall 203, or it can be located on the side wall 202 at the other end of the reaction chamber 20; this invention is not limited to this. The reactive gas flows into the reaction chamber 20 from the gas injection port 204, then flows above the surface of the wafer W, and forms a thin film of the desired material on the surface of the wafer W through a chemical reaction. Finally, the reactive gases that have not yet reacted and the reaction byproducts flow out of the gas outlet 205 to the outside of the reaction chamber 20.

[0067] like Figure 3 , Figure 4As shown, a single-piece tray 220 is provided inside the reaction chamber 20, and a recess 223 for accommodating a wafer carrier 230 is provided on the upper surface of the tray 220. Gas at a certain pressure is introduced into the special air passage 224 in the recess 223 through the airflow channel 221 in the tray 220, so that the wafer carrier 230 can be rotated by air flotation, so that different types of reactive gases reaching the upper surface of the wafer can be uniformly distributed and deposited on the wafer W.

[0068] The heating device is located below the tray 220 and heats the tray 220 through induction heating. The heat generated by the tray 220 is transferred to the wafer W through the wafer carrier 230, bringing the wafer W to the required process temperature. Figure 3 As shown, wafer W includes a disk-shaped central region Wa, and a middle region Wb and an edge region Wc surrounding the central region Wa. The uniformity of the radial temperature distribution of the wafer determines the quality of the thin film deposited on the surface of wafer W.

[0069] In this embodiment, as Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, the heating device includes a main heating coil 261 and a supplementary heating coil 262 arranged at intervals in the horizontal direction. Preferably, the heating power of the main heating coil 261 and / or the supplementary heating coil 262 is independently adjustable. In this embodiment, as... Figure 3 As shown, the main heating coil 261 is located near the gas injection port 204, and the supplementary heating coil 262 is located near the gas outlet 205. In another embodiment, the main heating coil 261 is located near the gas outlet 205, and the supplementary heating coil 262 is located near the gas injection port 204.

[0070] In this embodiment, as Figure 4 , Figure 6 As shown, the tray 220 has a rectangular structure. Both the main heating coil 261 and the supplementary heating coil 262 are rectangularly wound flat coils. Each section of the main heating coil 261 and the supplementary heating coil 262 is parallel to either the long or short side of the tray 220. For example... Figure 6 As shown, the maximum segment length of the main heating coil 261 along the long side of the tray 220 (i.e., the flow direction of the reactant gas in this embodiment) is denoted as L2. The maximum segment length of the main heating coil 261 along the short side of the tray 220 is denoted as L1. Let d represent the wafer diameter, 0.5... <d / L1<1,0.6<d / L2<1.2。

[0071] In this embodiment, the wafer W is heated jointly by the main heating coil 261 and the supplementary heating coil 262. Figure 6As shown, the outermost turns of the main heating coil 261 and the supplementary heating coil 262 are located on the outside of the wafer W. The main heating coil 261 and the supplementary heating coil 262 can heat not only the tray area directly below the wafer W, but also the tray area located on the outside of the wafer W. This prevents the tray area on the outside of the wafer W from being underheated, which would result in a lower temperature in the wafer edge region Wc.

[0072] In a preferred embodiment, at least one apex corner of the tray 220 is chamfered, which can effectively reduce the temperature gradient in the apex corner area of ​​the tray and greatly reduce the probability of tray cracking. In a more preferred embodiment, the two apex corners of the tray 220 near the gas outlet 205 are chamfered.

[0073] like Figure 6 As shown, in the horizontal direction, the wafer center is located between the winding center of the main heating coil 261 and the winding center of the supplementary heating coil 262. The technical idea of ​​this invention is to avoid insufficient heating of the wafer center region Wa by the main heating coil 261 (in this case, the wafer center corresponds to the winding center of the main heating coil 261) by offsetting the wafer center from the winding center of the main heating coil 261, and to supplement the heating of the wafer edge region Wc by the supplementary heating coil 262, thereby improving the uniformity of the radial temperature distribution of the wafer.

[0074] It should be noted that the winding center of the main heating coil 261 and the supplementary heating coil 262 in this invention does not refer to the geometric center of the main heating coil 261 and the supplementary heating coil 262, but rather to the center of the space surrounded by the innermost coil of the main heating coil 261 and the supplementary heating coil 262.

[0075] Figure 6 In this embodiment, the turn pitch (the distance between adjacent sections) of the main heating coil 261 and the supplementary heating coil 262 is the same everywhere. In other embodiments, the turn pitch at each position of the main heating coil 261 and the supplementary heating coil 262 can be adjusted according to actual needs, and the main heating coil 261 and the supplementary heating coil 262 are not centrally symmetrical. Since there is a voltage difference between adjacent sections of the main heating coil 261 and the supplementary heating coil 262, if the turn pitch is too small, arc discharge is likely to occur. In a preferred embodiment, the turn pitch of the main heating coil 261 and the supplementary heating coil 262 is... This not only improves the heating efficiency of tray 220, but also avoids the occurrence of arc discharge caused by excessively small turn spacing.

[0076] Figure 6In this design, the main heating coil 261 can adequately heat the tray area directly below the wafer center region Wa, thus providing the necessary heat to the wafer center region Wa. The space 2611 enclosed by the innermost coil of the main heating coil 261 corresponds to the wafer edge region Wc. To facilitate the processing and installation of the main heating coil 261, this space 2611 has a relatively large area, resulting in a lower magnetic field density within it. Furthermore, the current directions in sections 261A and 261B of the main heating coil 261 are opposite, causing the magnetic field lines generated in sections 261A and 261B within this space 261 to be opposite in direction. This further reduces the magnetic field energy within the space 261, leading to insufficient heating of the wafer edge region Wc by the tray area directly above the space 261, which can easily result in a lower temperature for the wafer edge region Wc.

[0077] like Figure 6 As shown, in this embodiment, sections 262A and 262B of the heating coil 262 induction heat the wafer edge region Wc to compensate for insufficient heating of the wafer edge region Wc by the tray region above the space 2611. The projections of each point on the wafer edge region Wc onto the tray 220 fall into... Figure 6 When the wafer W is within the fan-shaped region zone1, it receives heat from the heating coil 262. By independently adjusting the amplitude of the alternating current in the heating coil 262 and the turn pitch between sections 262A and 262B, the heat supply of the heating coil 262 to the fan-shaped region zone1 can be independently adjusted. As the wafer W rotates around its center, the temperature of the entire wafer edge region Wc can be independently adjusted through the heating coil 262, effectively compensating for the insufficient heating capacity of the main heating coil 261 to the wafer edge region Wc, and significantly improving the uniformity of the radial temperature distribution of the wafer and the uniformity of the thin film thickness on the wafer W surface.

[0078] In this invention, the alternating current frequencies in the main heating coil 261 and the supplementary heating coil 262 are the same. Section 261C of the main heating coil 261 and section 262A of the supplementary heating coil 262 are adjacent, and the alternating currents in sections 261C and 262A are in phase. This avoids mutual interference between the main heating coil 261 and the supplementary heating coil 262, and also enhances the alternating magnetic field between them, improving the heating efficiency of the tray area (including tray areas zone2, zone3, and zone4) between the main heating coil 261 and the supplementary heating coil 262.

[0079] On the other hand, the parallel arrangement of sections 261C and 262A helps to uniformly heat the tray area between the main heating coil 261 and the supplementary heating coil 262. This avoids excessive temperature differences between the tray area zone3 and the tray areas zone2 and zone4, which would lead to excessive temperature differences between the wafer center region Wb and the wafer edge region Wc, thus helping to improve the consistency of the wafer's radial temperature distribution.

[0080] Furthermore, by adjusting the spacing between segment 261C and segment 262A, for example... (This is only an example and is not intended to limit the invention.) The temperature of the tray areas zone2, zone3, and zone4 can also be adjusted, thereby adjusting the temperature of the wafer center area Wb and the wafer edge area Wc, reducing the temperature difference between the wafer center area Wb, the wafer edge area Wc and the wafer center area Wa, and improving the consistency of the wafer radial temperature distribution.

[0081] In another embodiment, such as Figure 7 As shown, the innermost ring of the heating coil 262 also surrounds a large space 2621, and the heat generated in the tray area corresponding to this space 2621 is also smaller. Figure 7 In this design, the horizontal distances between the wafer center and the winding centers of the main heating coil 261 and the supplementary heating coil 262 are not equal (the winding center of the main heating coil 261 is located inside the wafer edge, and the winding center of the supplementary heating coil 262 is located outside the wafer edge). This can prevent the wafer edge region Wc (or the wafer middle region Wb) from being located above both space 2611 and space 2621 at the same time, which would cause the temperature of the wafer edge region Wc (or the wafer middle region Wb) to be too low, making it impossible to generate a thin film of uniform thickness on the wafer W.

[0082] like Figure 6 , Figure 7 As shown, in the flow direction of the reactant gas, the section of the main heating coil 261 located at the wafer front end (also known as the upstream of the wafer) can preheat the reactant gas before it reaches the surface of wafer W. In a preferred embodiment, the main heating coil 261 has the minimum turn pitch at the wafer front end, which improves the preheating efficiency of the reactant gas, helps to preheat the reactant gas to the required temperature, and greatly improves the utilization rate of the reactant gas in the reaction chamber 20 (also known as improved source efficiency) and the deposition quality of the thin film on the wafer W surface. In this embodiment, the long side of the tray 220 is in the flow direction of the reactant gas, which helps to extend the preheating distance of the reactant gas and improve the preheating effect. Improving the utilization rate of the reactant gas can reduce dependence on limited natural resources and production costs, which is of positive significance for green and sustainable development.

[0083] In a preferred embodiment, in the direction of reaction gas flow, the distance between the wafer W and the short side of the tray near the gas injection port 204 is greater than the distance between the wafer W and the short side of the tray near the gas discharge port 205. This not only helps to fully preheat the reaction gas but also prevents excessive deposition of the reaction gas at the wafer back end (also known as the wafer downstream).

[0084] In another embodiment, the supplementary heating coil 262 is located near the gas injection port 204 and the main heating coil is located near the gas outlet 205. The reaction gas is preheated by the section of the supplementary heating coil 262 located at the front end of the wafer, and the supplementary heating coil 262 has the minimum turn pitch at the front end of the wafer.

[0085] In this embodiment, at least one of the main heating coil 261 and the supplementary heating coil 262 is a flat coil. In other embodiments, the height of any segment on the main heating coil 261 and / or the supplementary heating coil 262 can be adjusted to regulate the wafer temperature in different regions, thereby improving the uniformity of the radial temperature distribution of the wafer. For example, the temperature of the wafer edge region Wc can be adjusted by adjusting the height of segments 262A and 262B of the supplementary heating coil 262.

[0086] This embodiment also provides a vapor deposition apparatus 2, such as... Figure 3 As shown, it includes: a reaction chamber 20, a heating device as described in this invention, a first current regulating circuit 291, a second current regulating circuit 292, a cover plate 240, a diversion plate 280, and a loading ring 250.

[0087] like Figure 3 As shown, a gas injection port 204 and a gas outlet 205 are respectively provided on opposite sides of the reaction chamber 20. In this embodiment, the gas injection port 204 is located on the side wall of the reaction chamber 20, and the gas outlet 205 is located on the bottom wall of the reaction chamber 20. The guide plate 280 is located downstream of the tray 220, and the top of the guide plate 280 has a downward sloping surface, through which the gas in the reaction chamber 20 is guided to the gas outlet 205.

[0088] The reaction chamber 20 is equipped with a tray 220, on which a wafer carrier disk 230 for supporting the wafer W is mounted. Gas is introduced between the wafer carrier disk 230 and the tray 220 through an airflow channel 221 within the tray 220, enabling the wafer carrier disk 230 to rotate in an air-floating manner around its own center. In this embodiment, the reaction chamber 20 is a rectangular cavity, and the tray 220 is a rectangular tray.

[0089] The heating device is located below the tray 220. In a preferred embodiment, the heating device is housed within a protective cover (made of quartz) below the tray 220. The protective cover and the bottom wall of the reaction chamber 20 together form a sealed space. The protective cover prevents the heating device from being corroded by the gas inside the reaction chamber 20, thus helping to extend the service life of the heating device. In this embodiment, the heating device includes a main heating coil 261 and a supplementary heating coil 262, both of which are rectangularly wound.

[0090] The first current regulating circuit 391 and the second current regulating circuit 292 are used to independently regulate the heating power of the main heating coil 261 and the supplementary heating coil 262, respectively, so that the currents in adjacent sections of the main heating coil 261 and the supplementary heating coil 262 are in phase and frequency. In other embodiments, the vapor deposition apparatus 2 may also include only one of the first current regulating circuit 391 and the second current regulating circuit 292, which can also make the currents in adjacent sections of the main heating coil 261 and the supplementary heating coil 262 in phase and frequency.

[0091] like Figure 3 As shown, cover plate 240 is placed on tray 220 and surrounds the outer periphery of wafer carrier tray 230. A portion of the main heating coil 261 and a portion of the supplementary heating coil 262 are located directly below cover plate 240, which helps to preheat the reaction gas through cover plate 240 and prevents heat from the wafer edge region Wc from dissipating into the surrounding space.

[0092] The loading ring 250 is located above the wafer carrier 230 and between the wafer W and the cover plate 240. A step is formed on the inner edge of the upper surface of the loading ring 250, and the edge of the wafer extends above the step. When the loading ring 250 is moved, the edge of the wafer overlaps the step. A groove is formed on the lower surface of the loading ring 250 to accommodate a robotic arm, facilitating the robotic arm to reach into the groove and move the loading ring 250 and the wafer W together into and out of the reaction chamber 20.

[0093] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A heating device, said heating device being used in a vapor deposition apparatus, wherein the reaction chamber of the vapor deposition apparatus is provided with a tray for supporting a wafer, characterized in that, The heating device is located below the tray and includes a main heating coil and a supplementary heating coil arranged at intervals in the horizontal direction; At least a portion of the main heating coil and the supplementary heating coil are located directly below the wafer edge region; In the horizontal direction, the wafer center is located between the winding center of the main heating coil and the winding center of the supplementary heating coil.

2. The heating device as described in claim 1, characterized in that, The horizontal distances between the wafer center and the winding center of the main heating coil and the winding center of the supplementary heating coil are not equal.

3. The heating device as described in claim 2, characterized in that, The winding center of the main heating coil is located inside the wafer edge, while the winding center of the supplementary heating coil is located outside the wafer edge.

4. The heating device as described in claim 1, characterized in that, The heating power of at least one of the main heating coil and the supplementary heating coil is adjustable.

5. The heating device as described in claim 1, characterized in that, The alternating currents in the main heating coil and the supplementary heating coil have the same frequency and phase.

6. The heating device as described in claim 5, characterized in that, Both the main heating coil and the supplementary heating coil are wound in a rectangular shape; adjacent sections of the main heating coil and the supplementary heating coil are parallel to each other.

7. The heating device as claimed in claim 1, characterized in that, The tray has a rectangular structure, and the long side of the tray is in the direction of the flow of the reaction gas in the reaction chamber; each section of the main heating coil and the supplementary heating coil is parallel to the long side or the short side of the tray.

8. The heating device as described in claim 7, characterized in that, At least one of the top corners of the tray has a chamfered structure.

9. The heating device as described in claim 7, characterized in that, The outermost turns of both the main heating coil and the supplementary heating coil are located on the outside of the wafer.

10. The heating device as described in claim 9, characterized in that, The reaction chamber is provided with a gas injection port and a gas exhaust port on opposite sides; the main heating coil is close to the gas injection port and the supplementary heating coil is close to the gas exhaust port; or, the main heating coil is close to the gas exhaust port and the supplementary heating coil is close to the gas injection port.

11. The heating device as claimed in claim 10, characterized in that, In the direction of gas flow, the main heating coil or supplementary heating coil near the gas injection port has the minimum turn pitch at the position located at the front end of the wafer.

12. The heating device as claimed in claim 10, characterized in that, In the direction of gas flow, the distance between the wafer and the short side of the tray near the gas injection port is greater than the distance between the wafer and the short side of the tray near the gas discharge port.

13. The heating device as claimed in claim 6, characterized in that, The distance between adjacent sections of the main heating coil and the supplementary heating coil is 14. The heating device as claimed in claim 7, characterized in that, The maximum segment length of the main heating coil along the short side of the tray is L1; the maximum segment length of the main heating coil along the long side of the tray is L2; ​​let d represent the wafer diameter, 0.5 <d / L1<1,0.6<d / L2<1.2。 15. The heating device as claimed in claim 1, characterized in that, The height of any section on the main heating coil and / or supplementary heating coil is adjustable.

16. A vapor deposition apparatus, characterized in that, include: The reaction chamber contains a tray, on which a wafer carrier disk for supporting wafers is mounted; the wafer carrier disk is rotatable around its own center. The heating device as described in any one of claims 1 to 15 is disposed below the tray.

17. The vapor deposition apparatus as described in claim 16, characterized in that, It also includes at least one of a first current regulating circuit and a second current regulating circuit; the first current regulating circuit and the second current regulating circuit are used to independently regulate the heating power of the main heating coil and the supplementary heating coil, and to make the currents in adjacent sections of the main heating coil and the supplementary heating coil have the same frequency and phase.

18. The vapor deposition apparatus as described in claim 16, characterized in that, The tray is also provided with a cover plate, which surrounds the outer periphery of the wafer carrier tray.

19. The vapor deposition apparatus as described in claim 18, characterized in that, A section of the main heating coil and a section of the supplementary heating coil are located directly below the cover plate.

20. The vapor deposition apparatus as described in claim 18, characterized in that, It also includes a loading ring; the loading ring is disposed around the outer periphery of the wafer and located between the wafer and the cover plate; the inner edge of the upper surface of the loading ring has a step, the edge of the wafer extends above the step, and the lower surface of the loading ring has a groove for accommodating a robot arm.

21. The vapor deposition apparatus as described in claim 16, characterized in that, The reaction chamber has a gas injection port and a gas exhaust port on opposite sides, respectively; the gas injection port is located on the side wall of the reaction chamber, and the gas exhaust port is located on the bottom wall of the reaction chamber; the vapor deposition equipment also includes a flow guide plate located downstream of the tray; the top of the flow guide plate has a downward sloping surface, through which the gas in the reaction chamber is guided to the gas exhaust port.

22. The vapor deposition apparatus as described in claim 16, characterized in that, It also includes a protective cover located below the tray; the heating device is located inside the protective cover, which prevents the heating device from being corroded by the gas inside the reaction chamber.

Images