Heating device, CVD apparatus comprising the same

Abstract

A heating device for heating a rotatable substrate support is provided to improve temperature uniformity across the surface of the substrate support. The substrate support has an axis of rotation, and the heating device is positioned below the substrate support and vertically spaced from the substrate support. The heating device includes one or more first heaters for heating an annular region of the substrate support above the one or more first heaters and a plurality of auxiliary heaters below the annular region. The plurality of auxiliary heaters are at different distances from the axis of rotation to adjust the temperature of local regions within the annular region.

Description

TECHNICAL FIELD

[0001] The present invention relates to a heating device and to a chemical vapor deposition (CVD) apparatus comprising the same. BACKGROUND

[0002] Many semiconductor devices are fabricated by epitaxially growing semiconductor material on a substrate, which is typically a disc-shaped polycrystalline silicon material, commonly referred to as a wafer. During the fabrication process, the wafer is maintained at an elevated temperature and exposed to one or more chemical precursors that react or decompose on the surface of the substrate to produce a desired deposit. The precursors used in chemical vapor deposition typically include metals, such as metal hydrides, halides, halogen hydrides, and organometallic compounds. The precursors are combined with a carrier gas, such as nitrogen, but do not significantly react. The carrier gas and unwanted byproducts are exhausted from the reaction chamber.

[0003] Semiconductor compound layers are continuously grown using metal organic chemical vapor deposition (MOCVD) to fabricate devices formed from Group III-V semiconductor materials. Group III-V semiconductor materials include light emitting diodes (LEDs) and other high performance wafers such as laser diodes, optical sensors, and field effect transistors. These devices are formed on a substrate, such as a sapphire or silicon wafer, by reacting an organic gallium compound with ammonia. During the deposition of gallium nitride and related compounds, the wafer is maintained at a temperature between 500°C and 1200°C. Therefore, the heater assembly is typically heated to a temperature between 1000°C and 2200°C to achieve the wafer processing temperature. Many process parameters, such as pressure and gas flow rates, are also controlled to achieve the desired crystal growth process. After all of the semiconductor layers are formed and electrical contacts are tested, the wafer is diced into individual devices.

[0004] Multiple wafers are typically loaded on a substrate support in an MOCVD reactor to improve processing efficiency. This presents a more challenging task for the heating system of the substrate support, which must ensure that all of the wafers on the surface of the substrate support are within the proper temperature range. Otherwise, the material grown on wafers in the improper temperature range often has quality defects.

[0005] The current GaN mass production MOCVD equipment is mainly applied to the production of blue-green light LED for lighting, and the uniformity of the light emitting wavelength is not high, and the wavelength uniformity is generally less than 2nm. However, with the application prospect of Mini-LED and Micro-LED in high-end display, the wavelength uniformity in a single display is generally required to be less than + / - 2nm, and therefore higher requirements are put forward for the uniformity of the wavelength, and the wavelength uniformity needs to be less than 0.8nm or even less, which is equivalent to controlling the temperature of the entire wafer surface to be about + / - 1℃ when epitaxially growing at about 800℃. This puts forward higher requirements for the temperature control of the entire substrate support table during epitaxial growth and the fine adjustment of the local temperature field. SUMMARY

[0006] According to one aspect of the present application, a heating device for heating a rotatable substrate support table is provided, the substrate support table has a rotation axis (OO'), the heating device is located below the substrate support table and is spaced apart from the substrate support table in the vertical direction, the heating device comprises one or more first heaters for heating an annular region of the substrate support table above, and a plurality of auxiliary heaters below the annular region, and the plurality of auxiliary heaters have different distances from the rotation axis for adjusting the temperature of a local region in the annular region, each of the one or more first heaters comprises: two first terminals; a first heating section connecting the two first terminals for heating the substrate support table, the first heating section comprises a plurality of arc-shaped heating sections and a connecting portion for connecting different arc-shaped heating sections; each auxiliary heater comprises: two auxiliary terminals; an auxiliary heating section connecting the two auxiliary terminals for heating the substrate support table.

[0007] Optionally, the area of the auxiliary heating section in each of the auxiliary heaters is smaller than the area of any of the arc-shaped heating sections.

[0008] Optionally, the auxiliary heating section is below the first heating section.

[0009] Optionally, the radial position of the auxiliary heater corresponds to the gap between adjacent first arc-shaped heating sections or adjacent first heaters.

[0010] Optionally, the radial position of a first group of auxiliary heaters in the auxiliary heaters corresponds to the gap between adjacent arc-shaped heating sections or adjacent first heaters, and the radial position of a second group of auxiliary heaters in the auxiliary heaters corresponds to the first arc-shaped heating section.

[0011] Optionally, the first group of auxiliary heaters and the second group of auxiliary heaters are respectively located on both sides of the rotation axis (OO').

[0012] Optionally, the radial width of the at least one auxiliary heater is less than or equal to the width of the gap between adjacent first arc-shaped heating sections.

[0013] Optionally, the radial width of the at least one auxiliary heater is less than or equal to half of the radial width of the annular region.

[0014] Optionally, an auxiliary heating zone is provided between the multiple opposite connecting portions of the same first heating section or between the multiple opposite connecting portions of different first heating sections, and the auxiliary heater is located in the auxiliary heating zone.

[0015] Optionally, the area of the auxiliary heating zone is less than 1 / 10 of the area of the substrate support table.

[0016] Optionally, the auxiliary heater comprises a first auxiliary heater and a second auxiliary heater, the distance from the first auxiliary heater to the rotation axis (OO’) is greater than the distance from the second auxiliary heater to the rotation axis (OO’), and the number of the first auxiliary heaters is greater than or equal to the number of the second auxiliary heaters.

[0017] Optionally, the heating power of the first heater is more than 10 times the heating power of the auxiliary heater.

[0018] Optionally, the auxiliary heater comprises a first auxiliary heater and a second auxiliary heater, the distance from the first auxiliary heater to the rotation axis (OO’) is greater than the distance from the second auxiliary heater to the rotation axis (OO’), and the heating power of the first auxiliary heater is greater than the second auxiliary heater.

[0019] Optionally, the arc-shaped heating section comprises a first arc-shaped heating section and a second arc-shaped heating section, the distance from the first arc-shaped heating section to the rotation axis (OO’) is greater than the distance from the second arc-shaped heating section to the rotation axis (OO’), and the arc length of the first arc-shaped heating section is greater than the arc length of the second arc-shaped heating section.

[0020] Optionally, the heating device further comprises a heat insulation ring surrounding the auxiliary heater for insulating the first heating section from radiating heat to the auxiliary heater.

[0021] Optionally, the heating device further comprises a second heater, the second heater comprises two second connecting posts, and the second heating section of the second heater is located at the periphery of the annular region.

[0022] Optionally, the cross-sectional area of the first connecting post is more than 3 times the cross-sectional area of the auxiliary connecting post.

[0023] According to another aspect of the present application, there is provided a MOCVD apparatus, comprising: a gas-tight reaction chamber; a substrate support rotatably arranged in the reaction chamber for fixing a substrate on its upper surface; a heating device as described above arranged below the substrate support and vertically spaced apart from the substrate support by a distance for heating the substrate support.

[0024] Optionally, the heating powers of the different heaters and the plurality of auxiliary heaters are independently controllable.

[0025] Optionally, a heat-insulating shield is arranged below the heating device, and a liquid cooling pipe is fixed below the heat-insulating shield, so that a low-temperature area is formed below the heat-insulating shield, and the first terminals and the auxiliary terminals pass through the heat-insulating shield to reach the low-temperature area below.

[0026] According to another aspect of the present application, there is provided a heating device for heating a rotatable substrate support, the heating device being arranged below the substrate support and vertically spaced apart from the substrate support by a distance, the substrate support having a rotation axis (OO’), the heating device comprising at least one continuous first heater and a plurality of auxiliary heaters, the first heater comprising: two first terminals; a first heating section connecting the two terminals for heating the substrate support, the first heating section comprising a plurality of first arc-shaped heating sections and connecting portions for connecting different first arc-shaped heating sections; the distance from the nearest end of the first arc-shaped heating section to the rotation axis (OO’) is denoted as S min , and the distance from the farthest end of the first arc-shaped heating section to the rotation axis (OO’) is denoted as S max , the distance from the auxiliary heater to the rotation axis (OO’) is within the interval [S min , S max ], and each auxiliary heater comprises: two auxiliary terminals; an auxiliary heating section connecting the two terminals for heating the substrate support.

[0027] Herein, the “nearest end” of an arc-shaped heating section refers to the inner side edge of the arc-shaped heating section closest to the rotation axis, and the “farthest end” refers to the outer side edge of the arc-shaped heating section farthest from the rotation axis.

[0028] According to another aspect of the present application, there is provided an auxiliary heater for a MOCVD apparatus, the MOCVD apparatus comprising a rotatable substrate support having a rotation axis (OO') and a first heater, the first heater and the auxiliary heater being located below and vertically spaced apart from the substrate support, the first heater being configured to heat an annular region of the substrate support above, the auxiliary heater being located below the annular region and having a different distance from the rotation axis, the first heater and the auxiliary heater each comprising: two first terminals; and a first heating section connecting the two first terminals, the first heating section comprising a plurality of arc-shaped heating sections and connecting portions for connecting different arc-shaped heating sections, the first heating section being configured to heat the substrate support.

[0029] Optionally, the auxiliary heater comprises: two auxiliary terminals; and an auxiliary heating section connecting the two terminals, the auxiliary heating section being configured to heat the substrate support.

[0030] Optionally, the auxiliary heater is located at a radial position corresponding to a gap between adjacent first arc-shaped heating sections or between adjacent first heaters.

[0031] Optionally, the auxiliary heater is at least partially surrounded by a thermal isolation ring, the thermal isolation ring being configured to isolate the first heating section from thermal radiation of the auxiliary heater.

[0032] According to another aspect of the present application, there is provided a heating apparatus for heating a rotatable substrate support, the substrate support having a rotation axis (OO'), the heating apparatus being located below and vertically spaced apart from the substrate support, the heating apparatus comprising a main heater configured to heat the substrate support above and a plurality of auxiliary heaters, the plurality of auxiliary heaters having different distances from the rotation axis (OO'), each of the plurality of auxiliary heaters being configured to independently adjust a local temperature in the region heated by the main heater.

[0033] According to another aspect of the present application, there is provided a MOCVD apparatus, comprising: a gas-tight reaction chamber; a substrate support disposed within the reaction chamber and rotatable for holding a substrate on an upper surface thereof; and a heating apparatus as described above located below and vertically spaced apart from the substrate support, the heating apparatus being configured to heat the substrate support.

[0034] According to another aspect of the present application, there is provided a method for performing semiconductor process on a MOCVD apparatus as described above, characterized by placing a substrate on the substrate support, starting the main heater, and performing process on the substrate; detecting the process parameter distribution on the substrate surface; and adjusting the auxiliary heater to achieve the desired process parameter distribution.

[0035] According to another aspect of the present application, there is provided an auxiliary heater for a MOCVD apparatus, the MOCVD apparatus comprising a rotatable substrate support having a rotation axis (OO') and a main heater, the main heater and the auxiliary heater being located below the substrate support and vertically spaced apart from the substrate support by a distance, the main heater being configured to heat an annular region of the substrate support above, the auxiliary heater being located below the annular region and having different distances to the rotation axis, the auxiliary heater being configured to adjust the temperature of a local region in the annular region, the main heater each comprising two first terminals and a first heating section connecting the two first terminals, the first heating section comprising a plurality of arc-shaped heating sections and connecting portions connecting different arc-shaped heating sections.

[0036] According to another aspect of the present application, there is provided an auxiliary heater for a MOCVD apparatus, the MOCVD apparatus comprising a rotatable substrate support having a rotation axis (OO') and a main heater, the main heater and the auxiliary heater being located below the substrate support and vertically spaced apart from the substrate support by a distance, the main heater being configured to heat an annular region of the substrate support above, the auxiliary heater being located below the annular region and having different distances to the rotation axis, the auxiliary heater being configured to adjust the temperature of a local region in the annular region, the main heater each comprising two first terminals and a first heating section connecting the two first terminals, the first heating section comprising a plurality of arc-shaped heating sections and connecting portions connecting different arc-shaped heating sections. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 Fig. 1 is a schematic view of a MOCVD apparatus according to an embodiment of the present application;

[0038] Figure 2 Fig. 2 is a schematic view of a heating device according to an embodiment of the present application; Figure 3 Fig. 3 is a schematic view of a heating device according to another embodiment of the present application;

[0039] Figure 4 Fig. 4 is a schematic view of a heating device according to another embodiment of the present application; Figure 5 Fig. 5 is a schematic view of a heating device according to another embodiment of the present application; Figure 5 Fig. 6 is a schematic view of a heating device according to another embodiment of the present application;

[0040] Figures 6-10 Fig. 7 is a schematic view of a heating device according to another embodiment of the present application. DETAILED DESCRIPTION

[0041] The apparatuses / components of the present application can be applied to CVD apparatuses, particularly to CVD apparatuses, such as MOCVD apparatuses, in which a wafer holder (sometimes also referred to as a "wafer tray" in the art) for holding a wafer during deposition is rotated at a certain rotational speed to improve the quality of deposition. It is noted that the CVD apparatuses herein should be construed in a broad sense, including epitaxial growth apparatuses.

[0042] The heating apparatus of the present application and a MOCVD apparatus including the same will be described below with reference to the accompanying drawings. It is emphasized that the following description is exemplary only and other embodiments utilizing the present application are not excluded. Moreover, the technical features in various embodiments can be combined arbitrarily.

[0043] Figure 1 Fig. 1 is a schematic view of a MOCVD apparatus according to an embodiment of the present application. As shown in Fig. 1, the MOCVD apparatus 10 includes a reaction chamber 2 having a gas inlet 14 and a gas outlet 17. The gas inlet 14 can be provided at the top of the reaction chamber 2, and the gas outlet 17 can be provided at the bottom of the reaction chamber 2. Figure 1

[0044] The reaction chamber 2 has a top wall 22 at the top end, a bottom wall 24 at the bottom end, and a cylindrical side wall 26 extending between the top wall 22 and the bottom wall 24. The top wall 22, the bottom wall 24 and the side wall 26 together define a gas-tight interior processing volume 20 that can contain the gas emitted from the gas inlet 14. Although the reaction chamber 2 is shown as cylindrical, other embodiments can include reaction chambers having other shapes, such as conical or other revolved surfaces, square, hexagonal, octagonal, or any other suitable shape.

[0045] The gas inlet 14 is connected to a gas source for supplying process gases used in the processing of the wafer, such as carrier gases and reactive gases, such as sources of metal organic compounds and Group V metal elements. In a typical metal organic chemical vapor deposition process, the carrier gas can be nitrogen, hydrogen, or a mixture of nitrogen and hydrogen, so that the process gas at the top surface of the wafer holder can be composed primarily of nitrogen and / or hydrogen with some amount of reactive gas components. The gas inlet 14 is configured to receive the various gases and direct the process gas to flow in a generally downward direction.

[0046] The gas inlet 14 can also be connected to a cooling system configured to circulate a liquid through the gas distribution element to maintain the temperature of the element at a desired temperature during operation. In addition, similar cooling means (not shown) can be provided to cool the walls of the reaction chamber 2, including the top wall 22, the bottom wall 24 and the side wall 26.

[0047] ​Exhaust 17 is provided to exhaust gases (both reaction-generated exhaust and partially unreacted gases) from the interior processing volume 20 of the reaction chamber 2. Exhaust 17 includes an exhaust port 70 provided at or near the bottom of the reaction chamber 2, and a pump 18 or other vacuum source provided outside the reaction chamber 2 and in communication with the exhaust port 70 to provide motive force for the flow of gases.

[0048] The reaction chamber 2 is also provided with a substrate entry / exit port 30 for moving substrates into and out of the reaction chamber 2, and a ring-shaped reaction chamber liner 34 disposed proximate to and movable up and down along the sidewall 26. The reaction chamber liner 34 has an upper, closed position and a lower, open position. After processing of the substrates is complete, the reaction chamber liner 34 is moved downward (to the open position) to expose the substrate entry / exit port 30, and the substrates can be removed from the substrate entry / exit port 30. The next batch of substrates to be processed can be moved into the substrate entry / exit port 30. After the substrates are moved in, the reaction chamber liner 34 is moved upward (to the closed position) to cover the substrate entry / exit port 30, and the interior processing volume 20 is isolated from the substrate entry / exit port 30. In the closed position, the area defined by the reaction chamber liner 34 is a symmetrical circle, and the substrate entry / exit port 30 is "hidden" behind the reaction chamber liner 34 and is not exposed to the process gases. The process gases are exposed to the circumferential boundary defined by the reaction chamber liner 34, which ensures uniformity of the process environment. The drive mechanism (not shown) for controlling and driving the reaction chamber liner 34 up and down can be any type of drive, such as a mechanical, electromechanical, hydraulic, or pneumatic drive.

[0049] Although the reaction chamber liner 34 is shown as being cylindrical, other embodiments can include reaction chamber liners having other shapes, such as square, hexagonal, octagonal, or any other suitable shape.

[0050] The reaction chamber 2 is also provided with a rotatable shaft 44, a substrate support 40 mounted at the top of the shaft 44 and rotatable with the shaft 44, a loading mechanism (not shown), and a heating device 46. The shaft 44 is connected to a rotational drive mechanism (not shown), such as a motor drive, and is configured to rotate about its central axis. The shaft 44 can also be provided with an internal cooling channel (not shown) extending substantially along the axial direction of the shaft. The internal cooling channel can be connected to a cooling source, such that a fluid coolant can be circulated through the cooling channel and back to the cooling source.

[0051] Alternatively, the reaction chamber 2 can be provided with a rotating drum, and the edge portion of the substrate support is mounted on the circumferential portion of the drum opening. When the drum rotates, the substrate support is rotated along with the drum. The rotational drive mechanism is configured as described above, and will not be described again.

[0052] The substrate stage 40 is generally disk-shaped and can be made of a material that does not contaminate the MOCVD process and can withstand the temperatures experienced by the process (such as graphite, silicon carbide, or other heat-resistant materials). A plurality of generally circular substrate holding receptacles (not shown) are provided on the upper surface of the substrate stage 40, each substrate holding receptacle adapted to hold one substrate W. In one example, the substrate stage 40 may have a diameter of approximately 500 mm to approximately 1000 mm.

[0053] The loading mechanism (not shown) can move the substrate carrier 40 from the substrate inlet / outlet 30 into the reaction chamber 2 and mount the substrate carrier 40 on the top of the rotating shaft 44; it can also detach the substrate carrier 40 from the rotating shaft 44 and move it out of the reaction chamber 2 from the substrate inlet / outlet 30.

[0054] The heating device 46 is typically mounted on a heat shield 49 below the substrate support 40, primarily radiating heat to the bottom surface of the substrate support 40. Heat applied to the bottom surface of the substrate support 40 flows upwards through the substrate support 40 to the bottom surface of each substrate W, and then upwards through the substrate W to its top surface. A liquid-cooled pipe is fixed below the heat shield 49, creating a low-temperature region below the heat shield 49. The first and auxiliary terminals of the heating device, used for power input, pass through the heat shield 49 to reach this low-temperature region. Heat can also radiate from the top surface of the substrate support 40 and the top surface of the substrate W to cooler elements of the reaction chamber 2, such as the sidewall 26 of the reaction chamber 2 and the air inlet 14. Heat can also be transferred from the top surface of the substrate support 40 and the top surface of the substrate W to the processing gas flowing above these surfaces. The reaction chamber 2 also includes an outer bushing 28 to reduce the infiltration of processing gas into the area within the reaction chamber housing the heating device 46. In an exemplary embodiment, a heat shield (not shown) may be provided below the heating device 46, for example, configured to be parallel to the substrate support stage 40, to help guide heat from the heating device 46 upward toward the substrate support stage 40, rather than downward toward the bottom wall 24 at the bottom of the reaction chamber 2.

[0055] Figure 2 and Figure 3 This is a schematic diagram of a commonly used heating device, which can be applied to... Figure 1 The MOCVD equipment shown is used to ensure a relatively uniform temperature across the upper surface of the substrate support stage. For example... Figure 2 (Due to page width limitations, Figure 2 Only half of the structure of the substrate support stage 40' and heating device is shown. Both the substrate support stage 40' and the heating device are axisymmetric structures; therefore, this half of the structure shown is sufficient to clearly reveal the structure of the heating device and the relative positional relationship between the heating device and the substrate support stage 40'. Figure 3As shown, the heating device is located below and vertically spaced from the substrate support 40' to heat the substrate support 40' in a radiative manner. The heating device includes a continuous heater 46'. In the present patent document and hereinafter, the term "continuous" in relation to a heater means that the heating portions distributed in different regions in a single heater are electrically connected as a whole, and the heater can be fully operated by connecting a power source.

[0056] The heater 46' is located in the same plane and includes two terminals m' and n' and heating segments. The two terminals m' and n' are used to electrically connect the electrodes of a heating power source (not shown) so that the heating power source can be applied to the heater 46'. The heater used to connect the two terminals m' and n' includes a plurality of arc-shaped heating segments a', b', c', d', e' and f' distributed in concentric circles and connecting portions p' used to connect adjacent arc-shaped heating segments. The centers of the arc-shaped heating segments a', b', c', d', e' and f' are located on the rotation axis OO' of the substrate support 40'.

[0057] To solve the problem of uniform heating of the lower surface of the substrate support 40', one method is to provide a plurality of heaters 46', each of which covers a very small area and is electrically connected to an independent heating power source. That is, a plurality of heating regions, for example, 3 or 4 regions, are divided, and when the temperature of a certain region needs to be adjusted, only the heating power of the corresponding heater needs to be adjusted. Generally speaking, the smaller the area covered by each heater, the more obvious the improvement. However, this solution requires the addition of several or even more heating power sources, significantly increasing the cost. In addition, due to the increase in the number of heating power sources, the wiring connection between the heater and the heating power source becomes complex, and the automatic control of the controller to the heating power of the power source also becomes difficult.

[0058] Another method is to provide at least two arc-shaped heating segments, a first arc-shaped heating segment and a second arc-shaped heating segment, in the heater 46', and the resistivity per unit length of the two arc-shaped heating segments is not equal (for example, by changing the width of the arc-shaped heating segment c). The inequality is to improve the temperature uniformity of each region of the substrate support 40'. However, this method has the following disadvantages: (1) To obtain a uniform temperature distribution, different heating segments must be replaced. Replacing the heating segment must be done when the machine is shut down, and it is impossible to adjust the temperature distribution of the local region in real time during the process processing; (2) Each time the temperature distribution is modified, a new set of heaters must be reprocessed, and testing and optimization must be performed before finalizing. This undoubtedly increases the cost and prolongs the production cycle.

[0059] The inventor of the present application is committed to improving the above-mentioned defects. In research and experiments, the inventor found that when processing a substrate, the heater is fixed on the heat shield plate, and the substrate support table above the heater is rotating along the rotation axis OO'. When a heater is arranged at an arbitrary point on the heat shield plate, the heating track of the heater is a circle with the distance from the heater to the rotation axis as the radius. Since the heater has a radial width, its actual heating area is an annular area. It can be known that the area heated by each arc-shaped heating section is also an annular area, the inner half pitch of the annular area corresponds to the distance from the inner side boundary of the arc-shaped heating section in the radial direction to the rotation axis, and the outer half pitch of the annular area corresponds to the distance from the outer side boundary of the arc-shaped heating section in the radial direction to the rotation axis. The heating area of the connecting part is also an annular area, which basically covers the gap area between the adjacent arc-shaped heating sections in the radial direction. Therefore, when a small-power auxiliary heater is arranged on the heat shield plate, the auxiliary heater can adjust the temperature of the annular area where the auxiliary heater is located, which is approximately the vicinity of the circumference with the distance from the auxiliary heater to the rotation axis as the radius. When the above-mentioned first heater and auxiliary heater are arranged on the heat shield plate together, the first heater is used to control the heating temperature of the substrate support table due to its large heating area, and the auxiliary heater can be used to continuously fine-tune the temperature of the annular area where the auxiliary heater is located in real time according to the position of the auxiliary heater, so as to achieve the purpose of local temperature control.

[0060] According to the above solution idea, the inventor designs a heating device for heating a rotatable substrate support table, the substrate support table has a rotation axis (OO'), the heating device is located below the substrate support table and is separated from the substrate support table in the vertical direction by a distance, the heating device comprises one or more first heaters and a plurality of auxiliary heaters, the one or more first heaters are used to heat an annular area of the substrate support table above, the plurality of auxiliary heaters are below the annular area, and the plurality of auxiliary heaters have different distances from the rotation axis and are used to adjust the temperature of a local area in the annular area, the one or more first heaters each comprise: two first terminals; a first heating section connecting the two first terminals, used to heat the substrate support table, the first heating section comprises a plurality of arc-shaped heating sections and connecting parts for connecting different arc-shaped heating sections; and each auxiliary heater comprises: two auxiliary terminals; and an auxiliary heating section connecting the two auxiliary terminals, used to heat the substrate support table.

[0061] The annular area is defined as follows. The rotation axis (OO') vertically passes through the center O of the substrate support table, the inner radius of the annular area is denoted as S min , and the outer radius of the annular area is denoted as S max . The distance from each auxiliary heater to the rotation axis OO' of the substrate support table is in the interval [S min , Smax ].

[0062] Generally, the plurality of arc-shaped heating segments are distributed around the substrate support table. The arc length of the outer arc-shaped heating segments is greater than the arc length of the inner arc-shaped heating segments.

[0063] In one embodiment, the auxiliary heating segments of the auxiliary heater are directly below the arc-shaped heating segments, i.e. the auxiliary heater is covered by the arc-shaped heating segments. The auxiliary heater radiates heat to the first heater, and then to the lower surface of the substrate support table. In other embodiments, the auxiliary heating segments of the auxiliary heater are flush with the arc-shaped heating segments. Alternatively, the auxiliary heating segments of the auxiliary heater are slightly lower than the arc-shaped heating segments. In these embodiments, the auxiliary heater is not covered by the arc-shaped heating segments.

[0064] The auxiliary heater and the first heater are supplied with heating power by different heating power sources, so their output power can be independently controlled, and thus the heating effect can also be independently controlled. For example, the heating power of the auxiliary heater is 10-100 times less than that of the first heater. The projected area of the auxiliary heating segments on the substrate support table is much smaller than that of the arc-shaped heating segments, for example, 10-20 times smaller. And the projected area of the auxiliary heating segments is smaller than that of any of the arc-shaped heating segments.

[0065] When the substrate support table above the auxiliary heater rotates, the auxiliary heater can heat the temperature of the area near the circumference with the distance from the rotation axis OO' as the radius. By setting the auxiliary heater at different distances from the rotation axis OO', the temperature of the circumference with different distances as the radius can be heated. Therefore, by setting the distance of the auxiliary heater from the rotation axis OO' within the interval [S min , S max ], the auxiliary heater can fine-tune the temperature of the required local area in the entire annular heating area of the first heater. According to different needs, different numbers of auxiliary heaters can be set, and different distances of these auxiliary heaters from the rotation axis OO' can be set.

[0066] The distance of the auxiliary heater from the rotation axis OO' can be set to any value within the interval [S min , S max ]. And since the auxiliary heater heats the temperature of the area near the circumference with the distance from the rotation axis OO' as the radius, the auxiliary heater can be set at any position on the circumference. In other words, the auxiliary heater does not have to be arranged in a straight line along the radial direction, and its radial arrangement can be arbitrary.

[0067] In another embodiment, the application also provides a heating device for heating a rotatable substrate support, the substrate support having a rotation axis (OO'), the heating device being located below the substrate support and spaced apart from the substrate support in a vertical direction, the heating device comprising a main heater for heating the substrate support and a plurality of auxiliary heaters, the plurality of auxiliary heaters being different in distance to the rotation axis (OO'), each of the plurality of auxiliary heaters being configured to independently adjust a local temperature in a region heated by the main heater.

[0068] The main heater comprises a main heating section, the main heating section comprising a plurality of arc-shaped heating sections. When the substrate support rotates, the plurality of auxiliary heaters are configured to heat the substrate support and form a plurality of auxiliary annular heating zones different in distance to the rotation axis, the plurality of auxiliary annular heating zones being independently adjustable in temperature to adjust a local temperature in a region heated by the main heater.

[0069] Optionally, when the substrate support rotates, a vertical projection of the arc-shaped heating sections on the substrate support forms a first annular region, and a vertical projection of at least one of the auxiliary heaters on the substrate support is at least partially in the first annular region.

[0070] Optionally, when the substrate support rotates, a vertical projection of the gaps between adjacent arc-shaped heating sections on the substrate support forms a second annular region, and a vertical projection of at least one of the auxiliary heaters on the substrate support is at least partially in the second annular region.

[0071] Figure 4 、 Figure 5 (a)、 Figure 5 (b) and Figure 5 (c) show a schematic view of a heating device according to an embodiment of the application. Figure 4 is a top view of the heating device; Figure 5 (a)、 Figure 5 (b) and Figure 5 (c) are cross-sectional views taken along the radial lines aa', bb' and cc' of the substrate support in Figure 4 for the sake of understanding, the relative position of the substrate support 40 is also shown in these figures. As Figure 4 、 Figure 5 (a)、 Figure 5 (b) and Figure 5As shown in (c), the heating device is located below the substrate support stage 40 and is vertically spaced a distance from the substrate support stage 40, heating the substrate support stage 40 radiatively. The heating device 46 includes a first heater 461 and an auxiliary heater 465. The first heater 461 includes multiple arc-shaped heating sections and connecting portions, which will be described in detail below. In other embodiments, the first heater 461 may also include only multiple arc-shaped heating sections without connecting portions. Each auxiliary heater 465 includes: two auxiliary terminals 465a; and an auxiliary heating section 465b connecting the two terminals.

[0072] like Figure 4 As shown, the heating device 46 includes two first heaters 461, and the number of arc-shaped heating sections in each first heater 461 is the same as the number of arc-shaped heating sections in the second heater. Figure 2 or Figure 3 The heaters 46' in the first heater 461 are different. For simplicity, the heating sections of the first heater 461 are labeled a to g from the inside to the outside, and the eight auxiliary heaters 465 are labeled A to H. It can be seen that the arc length of the outer heating section is greater than that of the inner section. Figure 4 and Figure 5 As shown in (a), the distance from the innermost arc-shaped heating section a to the rotation axis OO' is S. min The distance from the outermost edge of the outermost arc-shaped heating section h to the rotation axis OO' is S. max S min and S max That is, the inner and outer radii of the annular region. The distances from the auxiliary heaters A to H to the rotating shaft OO' are all within the interval [S]. min S max Within the annular region, the auxiliary heaters 465 are all located below the annular region. In the embodiment shown in the figure, the auxiliary heaters 465 are arranged sequentially along the radial direction, and the height of the auxiliary heaters is consistent with the height of the arc-shaped heating sections a to h. In an alternative embodiment, the auxiliary heaters 465 may also be randomly arranged radially, as long as each auxiliary heater 465 is below the annular region, that is, the distance to the rotation axis OO' is within the range [S]. min S max Within [the specified range]. In an alternative embodiment, the auxiliary heater 465 is located directly below the arc-shaped heating sections a to h.

[0073] The radial position AD of the auxiliary heater corresponds to the gap between adjacent first arc-shaped heating sections or between adjacent first heaters. Specifically, as described below... Figure 5 As shown in (a), the distances from the heating section in the first heater 461 and the gap between adjacent heating sections to the rotation axis OO' are schematically marked. For example, the distance from the gap between heating sections b and c to the rotation axis OO' is S. g1The distance from the gap between heating sections c and d to the rotating shaft OO' is S. g2 The distance from the heating section d to the rotation axis OO' is S. c1 The distance from heating section e to the rotation axis OO' is S. c2 .like Figure 5 As shown in (b), the auxiliary heaters AD are positioned such that their distance from the rotation axis OO' corresponds to the distance from the gap between adjacent heating sections to the rotation axis. Specifically, the distance of auxiliary heater A from the rotation axis OO' corresponds to S. g1 The distance from the auxiliary heater B to the rotating shaft OO' corresponds to S. g2 The arrangement of auxiliary heaters C and D follows the same principle. This arrangement facilitates temperature regulation above the gaps between adjacent heating sections. During the substrate fabrication process, the area above the circumference of the arc-shaped heating section can be effectively heated, while the area above the circumference of the gap between adjacent arc-shaped heating sections can only be heated through the connecting part. Since the heating area of ​​the connecting part is much smaller than the area of ​​the heating section, the area above the circumference of the gap cannot be effectively heated. Furthermore, the connecting part and the arc-shaped heating section are integrated and cannot be heated independently, resulting in uneven heating in the radial direction. In this embodiment, the distance from the auxiliary heater AD to the rotation axis OO' corresponds to the distance from the gap between adjacent heating sections to the rotation axis, and the auxiliary heater AD and the first heater 461 are powered separately. This effectively compensates for the heating effect above the circumference of these gaps or regulates the temperature control of the area above the gap. In another embodiment, the distance from the auxiliary heater to the rotation axis OO' also corresponds to the gap between adjacent first heaters.

[0074] It should be noted that in this specification, the phrase "radial" refers to the direction perpendicular to the rotation axis OO'. Radially arranged heaters can be located in the same plane or in different planes. The phrase "distance from the gap to the rotation axis OO'" refers to the distance from the radial center point of the gap to the rotation axis OO'. The phrase "distance from the auxiliary heater to the rotation axis OO'" refers to the distance from the radial center point of the auxiliary heater to the rotation axis OO'. The phrase "distance from the heating section to the rotation axis OO'" refers to the distance from the radial center point of the heating section to the rotation axis OO'. The phrase "corresponds to" means that the distance from the auxiliary heater to the rotation axis is equal to the distance from the arc-shaped heating section of the first heater to the rotation axis or the distance from the gap between the arc-shaped heating sections to the rotation axis; or, the distance from the auxiliary heater to the rotation axis and the distance from the arc-shaped heating section of the first heater or the distance from the gap between the arc-shaped heating sections to the rotation axis differ from the distance from the rotation axis by less than 5%; or, the difference between the distance from the auxiliary heater to the rotation axis and the distance from the arc-shaped heating section or the distance from the gap between the arc-shaped heating sections to the rotation axis is less than or equal to 10 mm, or less than or equal to 15 mm, or less than or equal to 17 mm.

[0075] The auxiliary heater 465 can also be located in other radial positions. For example, as... Figure 5 As shown in (c), the distance from the auxiliary heater EH to the rotating shaft OO' corresponds to the distance from the heating sections d, e, f, and g to the rotating shaft OO'. Specifically, the distance from the auxiliary heater E to the rotating shaft OO' corresponds to S. c1 The distance from the auxiliary heater F to the rotating shaft OO' corresponds to S. c2 The arrangement of auxiliary heaters G and H follows the same logic. This configuration of auxiliary heaters allows adjustment of the area above the circumference of the arc-shaped heating section.

[0076] Note that the auxiliary heater AH mentioned above is only schematically indicated to be located at the position relative to the rotation axis OO'. The number, location, and size of these auxiliary heaters can be changed according to process and space requirements.

[0077] In another embodiment, only auxiliary heater AD or only auxiliary heater EH may be provided. These auxiliary heaters may be located on one side of the rotation axis or arranged on both sides respectively.

[0078] like Figure 4 As shown, the auxiliary heating section 465b of the auxiliary heater is a heating section arranged in a serpentine pattern along the tangential direction of the substrate support stage. The radial width of this heating section is denoted as W. In one embodiment, this radial width W is less than or equal to the radial width ΔS of the gap between adjacent heating sections. c (like Figure 5 (a) and Figure 5 (b) shows this configuration. This arrangement allows the auxiliary heater to more precisely regulate the temperature above the circumference where the gap between the arc-shaped heating sections lies. In another embodiment, the radial width W of at least one auxiliary heater is less than or equal to (S max –S min ) / 2, which is less than or equal to half the radial width of the annular region.

[0079] The auxiliary heating section 465b of the auxiliary heater can also have other shapes, such as being arranged in a serpentine pattern along the radial direction of the substrate support stage, or having a spiral shape, etc.

[0080] The heating power of the first heater 461 is greater than the heating power of the auxiliary heater 465 used to adjust the temperature in the heating area of the first heater 461. Generally, the heating power of the first heater 461 is more than 10 times, for example, 20 times, 30 times, 100 times, etc., of the heating power of the auxiliary heater 465. In one embodiment, the heating power of the first heater 461 can reach 100 kW, and the heating power of the auxiliary heater 465 is about 1000 W. In another embodiment, because the heating area of the outer ring is larger than the heating area of the inner ring, the heating power of the auxiliary heater 465 with a greater distance to the rotation axis OO' is greater than the heating power of the auxiliary heater 465 with a smaller distance to the rotation axis OO'. For example, in Figure 4 In the embodiment shown in FIG. 6, the heating power of the auxiliary heater C is greater than the heating power of the auxiliary heater B; the heating power of the auxiliary heater B is greater than the heating power of the auxiliary heater A.

[0081] In one embodiment, the auxiliary heating area is provided between the plurality of opposite connecting portions P of the plurality of first heaters 461, and the auxiliary heater 465 is located in the auxiliary heating area. Optionally, the area of the auxiliary heating area is less than 1 / 10 of the area of the substrate support table. In other embodiments, if the first heater has only one continuous arc-shaped heating segment, the auxiliary heating area can be provided between the plurality of opposite connecting portions P of the continuous arc-shaped heating segment.

[0082] The following gives a plurality of embodiments of the heating device according to the present application.

[0083] Figure 6 The structural schematic diagram of the heating device according to another embodiment of the present application is shown. Different from the embodiment shown in Figure 4 In this embodiment, a different number of auxiliary heaters 465 are provided on circumferences with different distances to the rotation axis OO'. More auxiliary heaters 465 are provided on the outer circumferences than on the inner circumferences, because the heating area on the outer circumferences is larger, and more auxiliary heaters 465 are needed to adjust the temperature.

[0084] Figure 7 The structural schematic diagram of the heating device according to another embodiment of the present application is shown. In order to isolate the heat radiation of the first heating segment to the auxiliary heater 465, in this embodiment, the auxiliary heater 465 further comprises a heat insulation ring 465c provided around the auxiliary heating segment, which can effectively isolate the heat radiation of the first heater 461, so that the heating heat of the auxiliary heater is effectively applied to the substrate support table, and the temperature adjustment of the auxiliary heater is more accurate.

[0085] Figure 8A structural diagram of a heating device according to another embodiment of the present application is shown. In this embodiment, the heating device 46 can further include a second heater 462, both ends of which are electrically connected to electrodes of another heating power supply (not shown). The second heater 462 is located outside the first heater 461 and surrounds the first heater 461, and is used to heat the outermost edge region of the substrate support table 40. The second heater 462 can be a single or multiple circular arc structure, or a 1 / 2 or 1 / 4 circular arc structure. The thickness, material, etc. of the second heater 462 can be the same as those of the first heater 461. The width of the second heater 462 can be much smaller than the width of the first heater 461 at various locations, so as to provide higher heating power. In this embodiment, the first heater 461 and the second heater 462 are powered by different heating power supplies (not shown), so that they can be independently controlled without interfering with each other. For the convenience of unified support, the second heater 462 can be arranged in the same plane as the first heater 461, as shown. Figure 8 It should be noted that in this embodiment, the auxiliary heater 465 is similar to the auxiliary heater in Figures 5 to 7 , except that the auxiliary heating segments in the auxiliary heater 465 are arranged in a radial reciprocating manner, while the auxiliary heating segments in the auxiliary heater in Figures 5 to 7 are arranged in a circumferential reciprocating manner. These auxiliary heaters all serve to adjust the local temperature in the region heated by the first heater 461 and the second heater 462.

[0086] Figure 9 A structural diagram of a heating device according to another embodiment of the present application is shown. In this embodiment, the heating device 46 can further include a plurality of different first heaters, such as the first heater 461 and a first heater 463, both ends of which are electrically connected to electrodes of another heating power supply (not shown). The first heater 463 is located below the central region of the substrate support table. The specific structure of the first heater 463 is similar to that of the first heater 461, including a heating segment, which includes a plurality of arc-shaped heating segments and connecting portions for connecting different arc-shaped heating segments. The thickness, material, etc. of the first heater 463 can be the same as those of the first heater 461. The width of the first heater 463 can be much smaller than the width of the first heater 461 at various locations, so as to provide higher heating power. The first heater 463 is used to independently control the temperature of the central region of the substrate support table.

[0087] The first heater, the second heater and the auxiliary heater in the heating device of the present application are described above, and those skilled in the art can also conceive other heaters or heating sections. For example, the heaters can be inductively heated or resistively heated. The heating power of the first heater, the second heater and the auxiliary heater in the present application is independently controllable. For example, they are supplied by different heating power sources. Alternatively, the heating power of the heaters and the auxiliary heater is supplied by the same heating power source, and the power output of the same heating power source is divided into multiple paths to supply different heaters and auxiliary heaters, and the heating power distributed to each path can be adjusted.

[0088] The heating device 46 comprises the first heater 461 and / or the second heater 462 as the main heater of the present application for heating the substrate support, and the auxiliary heater 465 for heating the substrate support and forming several auxiliary annular heating zones with different distances to the rotation axis OO' of the substrate support, and the temperature of the several auxiliary annular heating zones can be independently adjusted to adjust the local temperature of the area heated by the main heater.

[0089] Figure 10 The structural schematic diagram of the heating device according to another embodiment of the present application is shown. In this embodiment, the heating device is located below the substrate support, and the heating device comprises the main heater 461, 462 and the auxiliary heater 465. The main heater 461, 462 is used to heat the substrate support above, and the auxiliary heater 465 is arranged along the radial direction of the substrate support, and each auxiliary heater 465 is used to independently adjust the local temperature in the area heated by the main heater 461, 462. The auxiliary heaters 465 are arranged in a straight line along the radial direction of the substrate support, as shown. Figure 10 Alternatively, the auxiliary heaters 465 can also be arranged in any azimuthal angle along the radial direction of the substrate support. For example, the auxiliary heaters 465 are arranged in a staggered manner along the radial direction, or the trajectory of the auxiliary heaters 465 arranged along the radial direction is an arc. It should be noted that the auxiliary heaters can also be arranged between the two main heaters 462 in the outermost circle. The main heater 461, 462 and the auxiliary heater 465 are arranged in the same plane. Alternatively, the main heater 461, 462 and the auxiliary heater 465 can also be arranged in different planes, i.e. the distance of the main heater 461, 462 to the substrate support is different from the distance of the auxiliary heater 465 to the substrate support. Alternatively, the auxiliary heater 465 can also be arranged directly below the main heater 461, 462, i.e. the vertical projection of the auxiliary heater 465 to the substrate support overlaps or at least partially overlaps with the vertical projection of the main heater to the substrate support.

[0090] In this embodiment, asFigure 10 As shown, the main heater 461 includes a plurality of arc-shaped heating segments 461a, 461b, 461c, and the plurality of arc-shaped heating segments 461a, 461b, 461c have connecting portions to connect the arc-shaped heating segments. When the substrate support rotates above the main heater 461, the vertical projection of the arc-shaped heating segment 461a on the substrate support forms a first annular region 501, and the vertical projection of the auxiliary heater 465a on the substrate support is at least partially in the first annular region 501, so that the auxiliary heater 465a mainly adjusts the temperature in the first annular region 501. Optimally, the auxiliary heater 465a is located in the first annular region 501, so that the auxiliary heater 465a can effectively adjust the temperature of the local region. Alternatively, the radial center of the auxiliary heater 465a can be radially offset from the radial center of the first annular region 501 by a distance ranging from less than 20 mm, alternatively, less than 15 mm, or less than 10 mm. The present application does not limit this, and the specific condition is determined as appropriate.

[0091] The arc-shaped heating segment 461b and the arc-shaped heating segment 461c have a gap therebetween, and when the substrate support rotates above these arc-shaped heating segments, the vertical projection of the gap on the substrate support forms a second annular region 502, and the vertical projection of the auxiliary heater 465b on the substrate support is at least partially in the second annular region 502, so that the auxiliary heater 465b mainly adjusts the temperature in the second annular region 502. Optimally, the auxiliary heater 465b is located in the second annular region 502, so that the auxiliary heater 465b can effectively adjust the temperature of the local region. Alternatively, the radial center of the auxiliary heater 465b can be radially offset from the radial center of the second annular region 502 by a distance ranging from less than 20 mm, alternatively, less than 15 mm, or less than 10 mm. The present application does not limit this, and the specific condition is determined as appropriate.

[0092] In this embodiment, the auxiliary heaters 465 are divided into two groups, and the vertical projections of the four auxiliary heaters in the first group on the substrate support are respectively in the plurality of annular regions formed by the vertical projections of the main heating segments on the substrate support. The vertical projections of the four auxiliary heaters in the second group on the substrate support are respectively in the plurality of annular regions formed by the vertical projections of the gaps between the adjacent main heating segments on the substrate support. The two groups of auxiliary heaters are arranged on the two sides of the rotation axis (OO’) of the tray, respectively. The present application does not limit this, and the specific condition is determined as appropriate.

[0093] Alternatively, the heating device further includes a driving device connected with the auxiliary heaters, and the driving device drives any auxiliary heater to move along the radial direction of the substrate support or along the direction of the rotation axis (OO’), so as to adjust the different local temperatures of the substrate support according to the actual process requirements.

[0094] Optionally, the heating device further comprises a power controller connected with the auxiliary heater, the power controller is used to adjust the heating power of any auxiliary heater, so as to adjust the different local temperature of the substrate support platform according to the actual process requirement.

[0095] Optionally, the auxiliary heater 465 has different heating power from the main heaters 461, 462. For example, the actual heating power of the main heaters 461, 462 is more than 15 times or more than 20 times of the actual heating power of the auxiliary heater.

[0096] Optionally, the main heaters 461, 462 can be inductively heated and / or resistively heated. The auxiliary heater 465 can also be inductively heated and / or resistively heated. For example, inductive heating includes RF coil heating; resistive heating includes heating sheet heating, heating wire heating or lamp tube type heating.

[0097] The material of the arc-shaped heating section and the connecting part in the main heaters 461, 462 can include refractory metal, graphite, tungsten, molybdenum, rhenium, tantalum, niobium, zirconium, or a combination or alloy thereof, superalloy material, silicon carbide, etc. The surface of the arc-shaped heating section and the connecting part and the surface of the auxiliary heating section can be at least partially covered with refractory metal or alloy, boron nitride, tantalum carbide, silicon carbide, etc. high-temperature coating material.

[0098] The auxiliary heater in the present application has the following advantages:

[0099] After long-term use of the heater assembly, the related components such as heat shields, heating sheet supports, conductive supports, etc. will deposit reaction products or the material grain will become larger, thereby changing the material properties, affecting the working performance of the heating sheet, causing the MOCVD process performance to drift, increasing instability, and requiring replacement of the heater parts to solve the problem. After long-term use of the MOCVD reaction cavity assembly, aging and surface modification will also occur, causing the heater radiation heating environment to change, thereby causing the MOCVD process performance to drift, requiring real-time adjustment of process parameters, and frequent cleaning and maintenance of the reaction cavity. The present disclosure can compensate for changes in temperature distribution by adjusting the power of the auxiliary heater without replacing the arc-shaped heating section in the main heater, which is simple and convenient, saves costs, and improves the utilization rate of the machine.

[0100] For different substrate support platforms (different substrate sizes and arrangement methods), different temperature distribution requirements often exist. The usual approach is to use different specifications of main heating sections to correspond to different temperature distributions, and when replacing one type of substrate support platform, a set of main heating sections must be replaced. The present application can adapt to different temperature distribution requirements by fine-tuning the power output of the auxiliary heater without changing the specifications of the main heating section. It has the advantages of strong adaptability, good adjustable performance, and high adjustment precision.

[0101] Due to the small size of the auxiliary heater, the relative position of the auxiliary heating section, the main heating section and the substrate support table can be changed to adjust the local temperature distribution more accurately.

[0102] The application also discloses a method for processing semiconductor by using the MOCVD device, which comprises: placing a substrate on the substrate support table, starting the main heater, and processing the substrate; detecting the distribution of the process parameters on the surface of the substrate; and adjusting the auxiliary heater to achieve the desired distribution of the process parameters. Optionally, the process parameters include the temperature and / or the wavelength of the thermal radiation on the surface of the substrate. The adjustment of the auxiliary heater can include any of the following: moving the auxiliary heater along the radial direction of the substrate support table, moving the auxiliary heater along the direction of the rotation axis (OO’), and adjusting the heating power of the auxiliary heater.

[0103] Although the application has been described in detail by the above preferred embodiments, it should be understood that the above description should not be considered as limiting the application. After reading the above description, various modifications and substitutions of the application will be apparent to those skilled in the art. Therefore, the scope of the application should be defined by the appended claims.

Claims

1. A heating device for heating a rotatable substrate support stage, characterized in that, The substrate support stage has a rotation axis (OO'), and the heating device is located below the substrate support stage and is vertically spaced a distance from the substrate support stage. The heating device includes a main heater and multiple auxiliary heaters. The main heater is used to heat the upper substrate support platform. The multiple auxiliary heaters are located at different distances from the rotation axis (OO'), and each of the multiple auxiliary heaters is used to independently adjust the local temperature in the area heated by the main heater; the main heater includes one or more first heaters, each first heater including multiple arc-shaped heating sections and connecting portions for connecting adjacent arc-shaped heating sections; the one or more first heaters are used to heat the annular area of ​​the upper substrate support stage, and the inner radius of the annular area is denoted as S. min The outer radius of the annular region is denoted as S. max The distance from each auxiliary heater to the axis of rotation is in the range [S]. min S max ]Inside; The radial position of the first group of auxiliary heaters in the auxiliary heaters corresponds to the radial position of the gap between adjacent arc-shaped heating sections, and the radial position of the second group of auxiliary heaters in the auxiliary heaters corresponds to the radial position of the arc-shaped heating section.

2. The heating device as described in claim 1, characterized in that, The multiple auxiliary heaters are arranged in a straight line.

3. The heating device as described in claim 1, characterized in that, The distance from the auxiliary heater to the substrate support stage may be the same as or different from the distance from the main heater to the substrate support stage.

4. The heating device as described in claim 1, characterized in that, When the substrate carrier rotates, the plurality of auxiliary heaters are used to heat the substrate carrier and form several auxiliary annular heating zones at different distances from the axis of rotation. The temperature of the several auxiliary annular heating zones can be adjusted independently to adjust the local temperature of the area heated by the main heater.

5. The heating device as described in claim 1, characterized in that, When the substrate carrier rotates, the vertical projection of the arc-shaped heating section on the substrate carrier forms a first annular region, and the vertical projection of at least one of the auxiliary heaters on the substrate carrier is at least partially located within the first annular region.

6. The heating device as described in claim 1, characterized in that, When the substrate carrier rotates, the gap between adjacent arc-shaped heating sections forms a second annular region on the vertical projection of the gap on the substrate carrier, and at least one of the auxiliary heaters is at least partially located in the second annular region on the vertical projection of the auxiliary heater on the substrate carrier.

7. The heating device as described in claim 1, characterized in that, The first group of auxiliary heaters and the second group of auxiliary heaters are located on both sides of the rotation axis (OO').

8. The heating device as described in claim 1, characterized in that, The radial width of at least one of the auxiliary heaters is less than or equal to the width of the gap between adjacent arc-shaped heating sections.

9. The heating device as described in claim 1, characterized in that, The main heater includes a plurality of first heaters, and an auxiliary heating zone is provided between a plurality of opposite connecting portions of the plurality of first heaters, wherein the auxiliary heater is located in the auxiliary heating zone.

10. The heating device as described in claim 9, characterized in that, The area of ​​the auxiliary heating zone is less than 1 / 10 of the area of ​​the substrate support stage.

11. The heating device as claimed in claim 1, characterized in that, The auxiliary heater includes a first auxiliary heater and a second auxiliary heater. The distance from the first auxiliary heater to the rotation axis (OO') is greater than the distance from the second auxiliary heater to the rotation axis (OO'), and the number of the first auxiliary heaters is greater than or equal to the number of the second auxiliary heaters.

12. The heating device as claimed in claim 1, characterized in that, The auxiliary heater includes a first auxiliary heater and a second auxiliary heater. The distance from the first auxiliary heater to the rotation axis (OO') is greater than the distance from the second auxiliary heater to the rotation axis (OO'), and the heating power of the first auxiliary heater is greater than or equal to the heating power of the second auxiliary heater.

13. The heating device as claimed in claim 1, characterized in that, The heating power of the main heater is more than 15 times that of the auxiliary heater.

14. The heating device as claimed in claim 1, characterized in that, The heating device also includes a heat insulation ring surrounding the auxiliary heater, which allows the heating heat from the auxiliary heater to be applied to the substrate support stage.

15. The heating device as claimed in claim 1, characterized in that, The heating device also includes a drive device connected to an auxiliary heater, which drives any one of the plurality of auxiliary heaters to move radially along the substrate support stage or along the rotation axis (OO').

16. The heating device as claimed in claim 1, characterized in that, The heating device also includes a power controller connected to an auxiliary heater, the power controller being used to adjust the heating power of any one of the plurality of auxiliary heaters.

17. The heating device as claimed in claim 1, characterized in that, The main heater or the auxiliary heater is heated by inductive heating and / or resistive heating.

18. The heating device as claimed in claim 1, characterized in that, The main heater also includes a second heater, which is located around and surrounds the first heater.

19. The heating device as described in claim 18, characterized in that, The heating power of the first heater, the second heater, and the auxiliary heater is independently controllable.

20. The heating device as described in claim 18, characterized in that, The second heater has a single-turn or multi-turn arc structure.

21. The heating device as described in claim 18, characterized in that, The main heater includes a plurality of the first heaters, one of which is located below the central region of the substrate carrier stage and is used to independently control the temperature of the central region of the substrate carrier stage.

22. An MOCVD apparatus, comprising: An airtight reaction chamber; A substrate support stage, which is rotatable and located inside the reaction chamber, is used to fix the substrate to its upper surface. A heating device, as described in any one of claims 1 to 21, located below the substrate support stage and at a vertical distance from the substrate support stage, is used to heat the substrate support stage.

23. The MOCVD apparatus as described in claim 22, characterized in that, The heating power of the main heater and multiple auxiliary heaters is independently controllable.

24. The MOCVD apparatus as described in claim 22, characterized in that, The heating device includes a heat insulation shield plate below it, and a liquid cooling pipe is fixed below the heat insulation shield plate, so that there is a low temperature zone below the heat insulation shield plate.

25. A method for performing semiconductor processing using an MOCVD apparatus as described in any one of claims 22 to 24, characterized in that, include: Place the substrate on the substrate carrier stage and start the main heater to perform substrate processing; Detect the distribution of process parameters on the substrate surface; Adjust the auxiliary heater to achieve the desired process parameter distribution.

26. The method as described in claim 25, characterized in that, The process parameters include the temperature of the substrate surface and / or the wavelength of thermal radiation.

27. The method as described in claim 25, characterized in that, The adjustable auxiliary heater includes any one of the following: moving the auxiliary heater radially along the substrate support stage, moving the auxiliary heater along the rotation axis (OO'), and adjusting the heating power of the auxiliary heater.

28. An auxiliary heater for an MOCVD apparatus, the MOCVD apparatus comprising a rotatable substrate stage having a rotation axis (OO') and a main heater, the main heater and the auxiliary heater being located below the substrate stage and vertically spaced apart from the substrate stage, the main heater being used to heat the upper substrate stage. The auxiliary heaters are located at different distances from the rotation axis (OO'), and are used to independently adjust the local temperature in the area heated by the main heater. The main heater includes one or more first heaters, each first heater comprising multiple arc-shaped heating segments and connecting portions for connecting adjacent arc-shaped heating segments. The one or more first heaters are used to heat the annular region of the upper substrate support stage, the inner radius of which is denoted as S. min The outer radius of the annular region is denoted as S. max The distance from each auxiliary heater to the axis of rotation is in the range [S]. min S max The radial position of the first group of auxiliary heaters in the auxiliary heaters corresponds to the radial position of the gap between adjacent arc-shaped heating sections, and the radial position of the second group of auxiliary heaters in the auxiliary heaters corresponds to the radial position of the arc-shaped heating section.

29. The auxiliary heater as described in claim 28, characterized in that, When the substrate carrier rotates, the auxiliary heater is used to heat the substrate carrier and form several auxiliary annular heating zones at different distances from the axis of rotation. The temperature of the several auxiliary annular heating zones can be adjusted independently to adjust the local temperature of the area heated by the main heater.

30. The auxiliary heater as described in claim 28, characterized in that, When the substrate carrier rotates, the vertical projection of the arc-shaped heating section on the substrate carrier forms a first annular region, and the vertical projection of at least one of the auxiliary heaters on the substrate carrier is at least partially located within the first annular region.

31. The auxiliary heater as described in claim 28, characterized in that, When the substrate carrier rotates, the gap between adjacent arc-shaped heating sections forms a second annular region on the vertical projection of the gap on the substrate carrier, and at least one of the auxiliary heaters is at least partially located in the second annular region on the vertical projection of the auxiliary heater on the substrate carrier.

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