Internal and external double-positioning supporting structure of semiconductor heat treatment equipment

Abstract

The invention discloses an inner and outer double-positioning supporting structure of semiconductor heat treatment equipment, and belongs to the technical field of semiconductor equipment. An annular positioning groove is formed in the end part of a cylindrical supporting ring, and an inner annular positioning surface is formed on the inner side wall, close to the axis of the cylindrical supporting ring, of the annular positioning groove; an outer annular positioning surface is formed on the inner side wall, far away from the axis of the cylindrical supporting ring, of the annular positioning groove; the edge of the edge supporting ring is provided with a barrel-shaped flange, and the flange of the edge supporting ring is located in the annular positioning groove of the barrel-shaped supporting ring; before the wafer is subjected to heat treatment, the turned-over edge of the edge supporting ring is matched with the inner annular positioning surface; and after the temperature of the wafer is changed to the process temperature, the flange of the edge support ring is matched with the outer annular positioning surface. According to the scheme, under the conditions of a cold state and thermal expansion caused by process high temperature, relative concentricity between process accessories can be kept, the process uniformity and stability are improved, heat radiation except a wafer is prevented from being transmitted to a pyrometer, and the temperature measurement precision is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor devices, and particularly relates to an internal and external double-positioning support structure for a semiconductor heat treatment device. Background Art

[0002] A semiconductor heat treatment device is a semiconductor device used for heating processes (more specifically, high-temperature heating processes), such as a rapid thermal processing (RTP) device. An example of the prior art is a U.S. patent for invention with the authorization publication number US9130001B2. Please refer to Figures 1A to 1D , in the process fittings (Process kits) of the existing semiconductor heat treatment device, there are generally an existing cylindrical support ring (cylinder) 11' and an existing edge support ring (edgering) 12'. The existing cylindrical support ring 11' is arranged on the rotor of a magnetic levitation motor through an upper support column 9 of the rotor below. The existing edge support ring 12' is placed on the existing cylindrical support ring 11'. A wafer 13 is placed on the existing edge support ring 12', so as to drive the wafer 13 to rotate around its center during the heat treatment process to make the process effects such as heating and film formation uniform. In particular, the rapid thermal processing device must rotate. Since the heating temperature can reach 1100°C, if the wafer is not rotated, the temperature uniformity will be very poor, which will cause the wafer to be thermally shocked and broken.

[0003] The edge of the existing edge support ring 12' has a downward-extending flange. In the cold state (that is, before the heat treatment and during the equipment installation and debugging), the inner side of the flange is in clearance fit with the outer cylindrical surface at the top of the existing cylindrical support ring 11' with a small clearance to ensure concentricity with a small error (as Figure 1B shown), and this clearance is, for example, less than 0.1 mm. Furthermore, the concentricity error between the two in the cold state is at most this clearance size of 0.1 mm. However, such a structure can only make the two concentric in the cold state, and the concentricity in the hot state cannot be guaranteed. During the process, the wafer will be heated to a process temperature of, for example, 1100°C. Consequently, the edge support ring is about 900°C, and the cylindrical support ring is about 500°C. Due to the different thermal expansion coefficients and temperatures of the edge support ring and the cylindrical support ring, the clearance between the two at the process temperature will be enlarged to, for example, 1.2 mm to 1.3 mm (as Figure 1C shown). The cylindrical support ring, the edge support ring, and the wafer are driven by the rotor of the magnetic levitation motor to rotate at a speed of, for example, 240 rpm or higher. During the hot-state rotation, the large clearance between the edge ring and the support ring will cause the non-concentricity error to reach 1.2 to 1.3 mm. Furthermore, as observed from a top view (as Figure 1D shown), since the thermal expansion deformation amount of the edge support ring is relatively large, there will be a smaller clearance on one side (the left side in the figure) and a larger clearance on the other side (the right side in the figure, that is, the position at C). And because it rotates during the process, the position C of the maximum clearance at the circular edge is uncertain. This will cause the following problems: 1. The eccentricity of the support structure means the deviation of the wafer from the rotation center, that is, the center of gravity deviation. When the cylindrical support ring, the edge support ring, and the wafer are driven by the magnetic levitation motor rotor to rotate, they will perform non-concentric rotational motions, resulting in increased axial and radial runouts of the rotor rotation and unstable rotation, affecting the stability of the equipment and the process. In severe cases, problems such as wafer springing and dropping may occur.

[0004] 2. Eccentricity will cause differences in heat conduction of the wafer surface through the edge support ring and the cylindrical support ring, making the wafer temperature uneven and unsatisfactory. The distance between the wafer surface near the maximum gap and the cylindrical support ring is closer, and the heat conduction effect is more obvious. As a result, the temperature at this position on the wafer surface will be lower. For the film-forming process, the film thickness at this position will be thinner, that is, the thinner film thickness area B shown in Figure 1D ; on the other side opposite in the circumferential position, the heat conduction effect is relatively poor, the wafer surface temperature is higher, and the film thickness will also be thicker, that is, the thicker film thickness area A is formed. Therefore, the uniformity of the wafer surface will deteriorate. Moreover, due to the uncertain position where the maximum gap is generated, the positions of the thicker and thinner film thicknesses of each wafer during continuous processing are also random, resulting in poor process stability and consistency.

[0005] 3. Since the gap between the edge support ring and the cylindrical support ring becomes larger, the thermal radiation of the heating lamp of the heat treatment equipment and the thermal radiation of other components in the equipment process chamber will more easily enter the back of the wafer through the larger gap position and be received by the thermometer (probe) 10. The reception of this thermal radiation other than the wafer by the thermometer will affect the temperature measurement accuracy, and the measured temperature error of the wafer will become larger, resulting in problems such as unsatisfactory process results such as film thickness changes. Summary of the Invention

[0006] Based on the technical problems existing in the prior art, the present invention provides an internal and external double-positioning support structure for a semiconductor heat treatment equipment, which solves the problems in the existing equipment such as the increase in the gap of the support structure and non-concentricity due to thermal expansion, thereby affecting the wafer temperature uniformity, process stability, and system temperature measurement accuracy, and realizes ensuring the concentricity of the process fittings and the wafer relative to the equipment in both the cold state and the hot state, and improving the process uniformity and stability.

[0007] According to the technical solution of the present invention, the present invention provides an internal and external double-positioning support structure for a semiconductor heat treatment device, including a cylindrical support ring and an edge support ring; an annular positioning groove is provided at the end of the cylindrical support ring, and the inner side wall of the annular positioning groove close to the axis of the cylindrical support ring forms an inner annular positioning surface, and the inner side wall of the annular positioning groove away from the axis of the cylindrical support ring forms an outer annular positioning surface; the edge of the edge support ring has a cylindrical flanging, and the flanging of the edge support ring is located in the annular positioning groove of the cylindrical support ring; before heat-treating the wafer, the flanging of the edge support ring matches the inner annular positioning surface to make the edge support ring concentric with the cylindrical support ring; after changing the temperature of the wafer to the process temperature, the flanging of the edge support ring matches the outer annular positioning surface to make the edge support ring concentric with the cylindrical support ring.

[0008] In some embodiments, the annular positioning groove of the cylindrical support ring includes an annular bottom, an inner annular side wall, and an outer annular side wall.

[0009] In some embodiments, the part of the edge support ring adjacent to the flanging at the edge is a support plate, the inner annular side wall is in contact with the support plate, and / or the flanging is in contact with the annular bottom.

[0010] In some embodiments, the height of the outer annular side wall is not less than the height of the inner annular side wall.

[0011] In some embodiments, before heat-treating the wafer, the flanging of the edge support ring is in clearance fit with the inner annular positioning surface with a clearance of <0.1 mm; after changing the temperature of the wafer to the process temperature, the flanging of the edge support ring is in clearance fit with the outer annular positioning surface with a clearance of <0.1 mm.

[0012] In some embodiments, the distance between the inner annular positioning surface and the outer annular positioning surface of the annular positioning groove is equal to the thickness of the flanging of the edge support ring plus 0.7 mm.

[0013] In some embodiments, the middle of the edge support ring has a wafer placement groove for placing the wafer.

[0014] In some embodiments, the cylindrical support ring is a vertically arranged cylindrical shape, the annular positioning groove is opened on the upper end surface of the cylindrical support ring, the edge support ring is placed above the cylindrical support ring, and the flanging extends downward from the edge support ring.

[0015] In some embodiments, a semiconductor heat treatment apparatus includes a vacuum chamber. A heating lamp is disposed above the vacuum chamber. The bottom of the vacuum chamber is a reflector plate. An annular bottom chamber is disposed below the vacuum chamber. A magnetic levitation motor rotor is disposed in the vacuum environment of the bottom chamber. A magnetic levitation motor stator corresponding to the magnetic levitation motor rotor is disposed outside the bottom chamber. An edge support ring is located inside the vacuum chamber. The lower end of the cylindrical support ring passes through the bottom of the vacuum chamber and enters the bottom chamber, and the bottom of the cylindrical support ring is connected to the magnetic levitation motor rotor through a rotor upper support column. A plurality of thermometers are disposed at the bottom of the vacuum chamber, and the thermometers are located inside the cylindrical support ring.

[0016] In some embodiments, a quartz plate is disposed above the vacuum chamber. A heating lamp housing is disposed above the quartz plate. A heating lamp is disposed inside the heating lamp housing. The reflector plate is located inside the cylindrical support ring. The bottom of the vacuum chamber further has a reflective annular plate, and the reflective annular plate is located outside the cylindrical support ring. The reflective annular plate is an annular structure with an inclined angle. The vacuum chamber is provided with a vacuum pumping port, a wafer transfer port, and a process gas inlet port.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are as follows: 1. The internal and external double-positioning support structure of the semiconductor heat treatment apparatus of the present invention can solve problems such as the deterioration of wafer process uniformity and stability, and unstable rotation caused by the increase of thermal expansion size deviation. The edge support ring and the cylindrical support ring are placed by gravity. In the prior art, the two are not concentric due to thermal expansion, which will cause different heat conduction effects on the circumference of the wafer, a larger temperature difference of the wafer, and ultimately unsatisfactory process results such as different film thicknesses of the heat treatment process on the wafer surface. The present invention adopts an internal and external double-positioning structure to achieve the cooperative positioning of the edge support ring in the cold state and the hot state respectively, ensuring the concentricity of the process fittings.

[0018] 2. In the internal and external double-positioning support structure of the semiconductor heat treatment equipment of the present invention, the annular positioning groove forms two blockages on both sides of the inner and outer sides of the edge support ring, which can be called a labyrinth structure, thus avoiding the problem of inaccurate temperature measurement caused by miscellaneous heat radiation; in the semiconductor heat treatment equipment, while the wafer is heated by heat radiation, it will also release heat radiation itself, and the temperature measurement is realized by the thermometer receiving the heat radiation of the wafer. In the prior art, although the edge support ring and the cylindrical support ring are designed to be in contact and fit, in fact, the flatness of the two contacting planes cannot be in a perfect state, so there will be heat radiation from the heating lamp or other components in the vacuum chamber entering from the poorly contacted places. Especially after the temperature rises, the edge support ring and the cylindrical support ring will also deform, and the deformation will increase the gap between the contacting surfaces of the two, resulting in more heat radiation leakage; the structure of the present invention increases the blockage while achieving positioning matching, so that the process of heat radiation outside the edge support ring and the cylindrical support ring directly or after reflection entering the interior and being received by the thermometer becomes extremely difficult. These miscellaneous heat radiations cannot reach the thermometer on the back of the wafer, that is, the thermometer will not be interfered by the heat radiation outside the wafer, so the temperature measurement is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1A is a schematic three-dimensional structure diagram of the support structure and the wafer in the prior art.

[0020] Figure 1B is a schematic cross-sectional structure diagram of the support structure and the wafer in the prior art in the cold state in the equipment.

[0021] Figure 1C is a schematic cross-sectional structure diagram of the support structure and the wafer in the prior art in the hot state in the equipment.

[0022] Figure 1D is a schematic top view structure diagram of the support structure and the wafer in the prior art in the hot state in the equipment.

[0023] Figure 2 is a schematic overall structure diagram of the semiconductor heat treatment equipment provided by the present invention.

[0024] Figure 3A is a schematic structure diagram of the internal and external double-positioning support structure provided by the present invention before heat treatment (cold state) of the wafer.

[0025] Figure 3B is a schematic structure diagram of the internal and external double-positioning support structure provided by the present invention after changing the wafer temperature to the process temperature (hot state).

[0026] Figure 4A is a schematic three-dimensional cross-sectional structure diagram of the internal and external double-positioning support structure provided by the present invention.

[0027] Figure 4B It is an exploded perspective view of the internal and external double-positioning support structure provided by the present invention.

[0028] Figure 5 It is a schematic top view of the internal and external double-positioning support structure and the wafer in the equipment provided by the present invention.

[0029] Figure 6A and Figure 6B are process result diagrams of two wafers processed by using the prior art solution.

[0030] Figure 7A and Figure 7B are process result diagrams of two wafers processed by using the solution of the present invention.

[0031] Explanation of reference numerals in the drawings: 1. Heating lamp housing; 2. Heating lamp; 3. Quartz plate; 4. Reflective annular plate; 5. Vacuum chamber; 6. Bottom chamber; 7. Magnetic levitation motor stator; 8. Magnetic levitation motor rotor; 9. Upper support column of the rotor; 10. Thermometer; 11. Cylindrical support ring; 12. Edge support ring; 13. Wafer; 14. Reflector; 15. Emissivity pyrometer; 16. Annular positioning groove; 17. Inner annular side wall; 18. Outer annular side wall. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the drawings in the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] In addition, it should be noted that for the convenience of description, only the parts related to the relevant invention are shown in the drawings. Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0034] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependent relationships.

[0035] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless clearly indicated otherwise in the context, it should be understood as "one or more".

[0036] The present invention provides an internal and external double-positioning support structure for a semiconductor heat treatment device, belonging to the technical field of semiconductor devices. In the prior art, taking a process temperature of 1100 °C as an example, at the process temperature, the cylindrical support ring (cylinder) and the edge support ring in the process kit will undergo thermal expansion and deformation, resulting in an increase in the gap between the two and non-concentricity, causing different effects of heat conduction on different positions of the wafer, resulting in uneven temperature on the wafer surface, affecting the temperature uniformity of the wafer. Moreover, since the deviation position of non-concentricity is uncertain, the process results of each wafer will also be inconsistent, resulting in poor process stability. In addition, part of the thermal radiation from the heating source and the chamber will reach the thermometer through the gap enlarged due to thermal expansion between the process kits, affecting the temperature measurement accuracy of the wafer. Furthermore, non-concentricity will also cause the center of gravity of the magnetic levitation rotation to shift, resulting in unstable rotation. The present invention aims to solve the above problems in the prior art, and can ensure the concentricity of the process kit and the wafer relative to the device both in the cold state and in the case of thermal expansion during the hot-state process at high temperature, improve the process uniformity and stability, and prevent thermal radiation other than the wafer from reaching the thermometer, thereby improving the temperature measurement accuracy.

[0037] Please refer to Figure 3A 、 Figure 3B , an internal and external double-positioning support structure for a semiconductor heat treatment device of the present invention includes a cylindrical support ring 11 and an edge support ring 12. An annular positioning groove 16 is provided at the end of the cylindrical support ring 11. The inner side wall of the annular positioning groove 16 close to the axis of the cylindrical support ring 11 forms an inner annular positioning surface, and the inner side wall of the annular positioning groove 16 far from the axis of the cylindrical support ring 11 forms an outer annular positioning surface. Generally, it also includes an annular bottom surface. The annular bottom surface, the inner annular positioning surface, and the outer annular positioning surface together form the inner side surface of the annular positioning groove 16. The edge of the edge support ring 12 has a cylindrical flange. The flange of the edge support ring 12 is located in the annular positioning groove 16 of the cylindrical support ring 11. Before heat-treating the wafer, the flange of the edge support ring 12 is matched with the inner annular positioning surface to make the edge support ring 12 and the cylindrical support ring 11 concentric. After the temperature of the wafer changes through the semiconductor heat treatment device, the edge support ring 12 and the cylindrical support ring 11 will undergo corresponding thermal deformations (a common and obvious thermal deformation process during heat treatment is the heating process). After the wafer temperature is changed to the process temperature, the flange of the edge support ring 12 is matched with the outer annular positioning surface to make the edge support ring 12 and the cylindrical support ring 11 concentric. The above matching effect of temperature and thermal deformation amount can be achieved through design and calculation of the structure.

[0038] More specifically, the above "concentric" means having good concentricity. For example, before heat-treating the wafer, the flanging of the edge support ring 12 and the inner annular positioning surface are in clearance fit with a clearance of <0.1 mm; after changing the wafer temperature to the process temperature, the flanging of the edge support ring 12 and the outer annular positioning surface are in clearance fit with a clearance of <0.1 mm; "in clearance fit with a clearance of <0.1 mm" means that the maximum clearance existing on the entire circumference is <0.1 mm.

[0039] Generally, before heat-treating the wafer corresponds to the cold state, and the temperature is, for example, room temperature; the process temperature corresponds to the hot state. The heating source of the semiconductor heat treatment equipment reaches a certain high temperature to heat the wafer to the process temperature, and at the same time, the temperatures of the other components in the equipment that come into contact with the high temperature or are affected by thermal radiation will also increase. After the temperature increases, both the edge support ring 12 and the cylindrical support ring 11 will undergo thermal expansion and the diameter size will increase. However, due to the different materials and temperatures of the two, the increased sizes of the diameters are different. Usually, the edge support ring 12 is directly irradiated by the heating source (heating lamp 2), so its temperature is higher and the increase in the diameter size is greater.

[0040] In a specific embodiment, the edge support ring 12 is made of silicon carbide material with physical properties close to those of the wafer to achieve as uniform thermal conduction as possible in the hot state. The cylindrical support ring 11 is made of black quartz material. The thermal expansion coefficient ω1 of the edge support ring = 4.0×10 -6 mm / °C, and the diameter D1 of the edge support ring = 330.5 mm. The thermal expansion coefficient ω2 of the cylindrical support ring = 5.7×10 - 7mm / ℃, the diameter D2 of the cylindrical support ring is 330.3 mm. The cold state temperature is taken as 20 °C, the temperature of the edge support ring during the process is 1000 °C, and the temperature of the cylindrical support ring is 500 °C. Furthermore, the expansion size A1 of the edge support ring = D1×ω1×(1000 - 20) = 1.29 mm; the expansion size A2 of the cylindrical support ring = D2×ω2×(500 - 20) = 0.09 mm. When in the hot state, the diameter difference between the edge support ring and the cylindrical support ring is A1 - A2 = 1.2 mm, that is, theoretically in the concentric case, the unilateral gap between their edges is about 0.6 mm; if the existing technical solution is adopted, when there is eccentricity, the minimum position of the gap between their edges is 0, and the maximum position is about 1.2 mm. The above is an exemplary calculation, which is further calculated and determined based on the actual situation. When the process temperature is about 1100 °C, the diameter gap difference between the edge support ring 12 and the cylindrical support ring 11 is 1.2 - 1.3 mm, and the radius gap difference is 0.6 - 0.65 mm. Accordingly, the preferred design is that the distance between the inner circumferential positioning surface and the outer circumferential positioning surface of the annular positioning groove 16 is equal to the thickness of the flanging of the edge support ring 12 plus 0.7 mm (the thickness of the flanging is small, so the thermal expansion amount in the thickness direction is extremely small). In this way, it can be ensured that the two can be fitted with a small gap of <0.1 mm both in the cold state and the hot state, ensuring good concentricity.

[0041] On the other hand, the existence of the annular positioning groove 16 forms an occlusion for the part where the edge support ring 12 and the cylindrical support ring 11 are in contact (that is, the part where a gap may be generated and heat radiation may pass through), which helps to avoid heat radiation leakage. Specifically, the annular positioning groove 16 of the cylindrical support ring 11 includes an annular bottom, an inner annular side wall 17 and an outer annular side wall 18. The annular bottom will be in contact with or nearly in contact with the flanging, and the inner annular side wall 17 and the outer annular side wall 18 extend from the annular bottom towards the edge support ring 12, surrounding and occluding both sides of the flanging.

[0042] Furthermore, the part adjacent to the flanging at the edge of the edge support ring 12 is a support plate in the shape of an annular plate. The inner annular side wall 17 is in contact with the support plate, and / or the flanging is in contact with the annular bottom. It can be understood that usually, in order for the edge support ring 12 and the cylindrical support ring 11 to be in contact by gravity, the contact position will naturally move under the condition of different thermal expansion amounts; if the two are fixedly connected, structural damage will be caused due to different thermal expansion amounts. For reference, see Figure 3A, when the inner annular side wall 17 is longer than the flanging, the inner annular side wall 17 contacts the support plate and the bottom of the flanging is suspended; when the flanging is longer than the inner annular side wall 17, the flanging contacts the bottom of the annular positioning groove 16 and the support plate is suspended. Preferably, the lengths of the flanging and the inner annular side wall 17 are similar. At the same time, the outer annular side wall 18 also has a sufficient length. For example, the height of the outer annular side wall 18 is not lower than that of the inner annular side wall 17, or the lengths of the three are similar, thus forming the state shown in the figure. No matter where the contact surface is, a labyrinth structure is formed, making it difficult for the external thermal radiation to directly enter or enter after bouncing into the interior of the space enclosed by the edge support ring 12 and the cylindrical support ring 11. Furthermore, it is difficult for the external thermal radiation to affect the thermometer 10 inside the space. The thermometer 10 can ideally basically only receive the thermal radiation from the wafer 13 to measure the temperature accordingly.

[0043] More specifically, in the illustrated embodiment, the cylindrical support ring 11 is vertically arranged, the plane where the annular bottom is located is horizontal, and the inner annular side wall 17 and the outer annular side wall 18 are respectively located on the inner circumferential and outer circumferential sides of the ring of the annular bottom; the plane where the support plate is located is horizontal and the flanging is vertically arranged. The middle of the edge support ring 12 has a wafer placement groove for placing the wafer 13; the basic structure of the edge support ring 12 can follow the prior art, and details such as its size and the flatness of the bottom of the flanging can be adjusted based on the concept of the present invention and specific designs. It can be understood that the focus of the present invention is that the flanging can be respectively matched with the inner and outer annular positioning surfaces in two states and at the same time this structure can also block thermal radiation. The rest of the specific structure is not limited to the illustrated embodiment.

[0044] Please refer to Figure 2, in a more specific embodiment, the semiconductor heat treatment equipment is a rapid thermal processing equipment. Among them, the cylindrical support ring 11 is a vertically arranged cylindrical shape, the annular positioning groove 16 is opened on the upper end surface of the cylindrical support ring 11, the edge support ring 12 is placed above the cylindrical support ring 11, and the flanging extends downward from the edge support ring 12. The semiconductor heat treatment equipment includes a vacuum chamber 5, a heating lamp 2 is arranged above the vacuum chamber 5, the bottom of the vacuum chamber 5 is a reflector 14, and an annular bottom chamber 6 is arranged below the vacuum chamber 5; a magnetic levitation motor rotor 8 is arranged in the vacuum environment in the bottom chamber 6, and a magnetic levitation motor stator 7 corresponding to the magnetic levitation motor rotor 8 is arranged outside the bottom chamber 6; the edge support ring 12 is located in the vacuum chamber 5, the lower end of the cylindrical support ring 11 passes through the bottom of the vacuum chamber 5 and enters the bottom chamber 6, and the bottom of the cylindrical support ring 11 is connected to the magnetic levitation motor rotor 8 through a rotor upper support column 9; a plurality of temperature sensors 10 are arranged at the bottom of the vacuum chamber 5, and the temperature sensors 10 are located inside the cylindrical support ring 11. The vacuum chamber 5 is provided with a vacuum pumping port, a wafer transfer port, and a process gas inlet; a quartz plate 3 is arranged above the vacuum chamber 5, a heating lamp housing 1 is arranged above the quartz plate 3, and a heating lamp 2 is arranged inside the heating lamp housing 1; the reflector 14 is located inside the cylindrical support ring 11, and the vacuum chamber 5 further has a reflective annular plate 4 at the bottom, the reflective annular plate 4 is located outside the cylindrical support ring 11, and the reflective annular plate 4 is an annular structure with an inclined angle; at least one emissivity pyrometer 15 is included in the temperature sensors 10.

[0045] Further, for example, the heating lamp housing 1 is a circular honeycomb structure. A heating lamp 2 is installed in the honeycomb holes. Circulating cooling water is introduced into the interior of the heating lamp housing 1 to cool the housing. The heating lamp 2 is a columnar halogen lamp and is installed in the corresponding holes of the heating lamp housing 1 to achieve rapid heating and temperature control of the wafer. The quartz plate 3 is a circular flat plate structure that isolates the heating lamp from the vacuum chamber. A sealing ring is provided between it and the vacuum chamber body 5 to achieve vacuum sealing of the vacuum chamber. The reflective annular plate 4 is an annular structure with a certain inclination angle. Its upper surface is polished and has a high reflectivity, with a reflectivity greater than 85%. It reflects thermal radiation, assists in the rapid heating of the wafer, and at the same time prevents the chamber from overheating. The vacuum chamber body 5 has an internal circular cavity and an external square structure. A vacuum pumping port, a wafer transfer port, and a process gas inlet are provided thereon to provide a necessary vacuum environment for wafer processing. The bottom chamber 6 is an annular structure with a boss in the middle. The flange surface is installed at the bottom of the vacuum chamber body 5. A sealing ring is provided between it and the vacuum chamber body 5 to achieve vacuum sealing. Above the middle boss, the reflective plate 4 is installed. Corresponding holes are drilled along the radius direction of the middle boss corresponding to the holes on the reflective plate. The thermometer passes through these holes and is flush with the surface of the reflective plate. The magnetic levitation motor stator 7 is an annular structure and is installed in the atmospheric environment outside the concentric circle of the bottom chamber 6. The magnetic levitation motor rotor 8 is an annular structure and is placed in the vacuum environment of the concentric circular groove of the bottom chamber 6. The support columns 9 on the rotor are several columnar support structures and are installed on the magnetic levitation motor rotor 8. The thermometers 10 are several columnar high-temperature thermometers and are arranged along the radius direction of the reflective plate 14. These high-temperature thermometers are used to receive the radiation signals emitted by the wafer 13 once and reflected multiple times by the reflective plate 14. The cylindrical support ring 11 is a circular (cylindrical) structure and is placed on the support columns 9 on the rotor and is made of black quartz. The edge support ring 12 is a circular structure and is placed on the cylindrical support ring 11 and is made of silicon carbide. The wafer 13 is placed on the edge support ring 12. The magnetic levitation motor stator 7 is energized to control the suspension and rotation of the magnetic levitation rotor 8, and then drive the support columns 9 on the rotor, the cylindrical support ring 11, the edge support ring 12, and the wafer 13 to suspend and rotate, so that the heating of the wafer 13 is uniform and the process uniformity is ensured. The reflective plate 14 is a circular plate structure, and its surface is coated with a uniform high-reflectivity film layer. It uniformly reflects the thermal radiation emitted by the wafer 13 back to the wafer 13 to make the temperature of the wafer 13 uniform. Its high reflectivity repeatedly reflects the thermal radiation of the wafer 13 so that the apparent emissivity of the wafer approaches 1, that is, a simulated blackbody structure is formed. At this time, the temperature accuracy measured by the thermometers 10 receiving the primary radiation and the repeatedly reflected radiation signals of the wafer 13 is very high, and the error can be ±0.5°C.The emissivity pyrometer 15 is a columnar pyrometer that can measure both emissivity and radiation signal. Emissivity + transmittance + reflectivity = 1. Since the transmittance of the wafer is 0, the emissivity + reflectivity of the wafer = 1. The method for the emissivity pyrometer 15 to measure the true emissivity of the wafer is that it emits infrared light, which is reflected back by the wafer after reaching the wafer. According to the emission amount and the reflected amount received from the wafer, the reflectivity of the wafer can be calculated, and 1 - reflectivity is the true emissivity of the wafer. This method can accurately measure the true emissivity of each wafer. On the premise of obtaining the true emissivity of the wafer and the reflectivity of the reflector under the sensitive bandwidth of the pyrometer of 700 - 1000 nm, and simulating the radiation signal received by the pyrometer in the blackbody environment, the accurate wafer temperature can be calculated through the algorithm.

[0046] In summary, the internal and external double-positioning support structure of the semiconductor heat treatment equipment of the present invention can solve problems such as the deterioration of wafer process uniformity and stability and unstable rotation caused by the increase in thermal expansion size deviation; the edge support ring and the cylindrical support ring are placed relying on gravity. In the prior art, they will be non-concentric due to thermal expansion, which will lead to different heat conduction effects on the circumference of the wafer and a larger temperature difference on the wafer, ultimately resulting in unsatisfactory process results such as different film thicknesses of the heat treatment process on the wafer surface; the present invention adopts an internal and external double-positioning structure to achieve the matching positioning of the edge support ring in the cold state (for example, when the equipment is at room temperature) and the hot state (for example, when the equipment is at the process temperature of 1100 °C), ensuring the concentricity of the process accessories. In the internal and external double-positioning support structure of the semiconductor heat treatment equipment of the present invention, the annular positioning groove forms two blockings on the inner and outer sides of the edge support ring, which can be called a labyrinth structure, thus avoiding the problem of inaccurate temperature measurement caused by stray thermal radiation; in the semiconductor heat treatment equipment, while the wafer is heated by thermal radiation, it will also release thermal radiation itself, and the temperature is measured by receiving the thermal radiation of the wafer through the thermometer. In the prior art, although the edge support ring and the cylindrical support ring are designed to be in contact and fit, in fact, the flatness of the two contacting planes cannot be in a perfect state, so there will be thermal radiation from the heating lamp or other components in the vacuum chamber entering from the poorly contacting place. Especially after the temperature rises, it will also cause deformation of the edge support ring and the cylindrical support ring, and the deformation will increase the gap between the contacting surfaces of the two, resulting in more thermal radiation leakage; the structure of the present invention increases the blocking while achieving positioning matching, making it extremely difficult for the thermal radiation outside the edge support ring and the cylindrical support ring to directly or be reflected into the interior and be received by the thermometer. These stray thermal radiations cannot reach the thermometer on the back of the wafer, that is, the thermometer will not be interfered by the thermal radiation outside the wafer, so the temperature measurement is more accurate.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An internal and external double-positioning support structure for a semiconductor heat treatment equipment, characterized in that, It includes a cylindrical support ring (11) and an edge support ring (12); an annular positioning groove (16) is provided at the end of the cylindrical support ring (11), the inner side wall of the annular positioning groove (16) close to the axis of the cylindrical support ring (11) forms an inner annular positioning surface, and the inner side wall of the annular positioning groove (16) far from the axis of the cylindrical support ring (11) forms an outer annular positioning surface; the edge of the edge support ring (12) has a cylindrical flanging, and the flanging of the edge support ring (12) is located in the annular positioning groove (16) of the cylindrical support ring (11); before heat-treating the wafer, the flanging of the edge support ring (12) matches the inner annular positioning surface to make the edge support ring (12) concentric with the cylindrical support ring (11); after changing the wafer temperature to the process temperature, the flanging of the edge support ring (12) matches the outer annular positioning surface to make the edge support ring (12) concentric with the cylindrical support ring (11).

2. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 1, characterized in that, The annular positioning groove (16) of the cylindrical support ring (11) includes an annular bottom, an inner annular side wall (17) and an outer annular side wall (18).

3. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 2, characterized in that, The part of the edge support ring (12) adjacent to the flanging at the edge is a support plate, the inner annular side wall (17) is in contact with the support plate, and / or the flanging is in contact with the annular bottom.

4. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 3, wherein, The height of the outer annular side wall (18) is not lower than the height of the inner annular side wall (17).

5. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 1, characterized in that, Before heat-treating the wafer, the flanging of the edge support ring (12) is in clearance fit with the inner annular positioning surface with a clearance of <0.1mm; after changing the wafer temperature to the process temperature, the flanging of the edge support ring (12) is in clearance fit with the outer annular positioning surface with a clearance of <0.1mm.

6. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 1, wherein, The distance between the inner annular positioning surface and the outer annular positioning surface of the annular positioning groove (16) is equal to the thickness of the flanging of the edge support ring (12) plus 0.7mm.

7. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to any one of claims 1-6, characterized in that, The middle part of the edge support ring (12) has a wafer placement groove for placing the wafer (13).

8. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 7, characterized in that, The cylindrical support ring (11) is a vertically arranged cylinder, the annular positioning groove (16) is opened on the upper end surface of the cylindrical support ring (11), the edge support ring (12) is placed above the cylindrical support ring (11), and the flanging extends downward from the edge support ring (12).

9. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 8, characterized in that, The semiconductor heat treatment equipment includes a vacuum chamber (5), a heating lamp (2) is arranged above the vacuum chamber (5), the bottom of the vacuum chamber (5) is a reflector (14), and an annular bottom chamber (6) is arranged below the vacuum chamber (5); a magnetic levitation motor rotor (8) is arranged in the vacuum environment in the bottom chamber (6), and a magnetic levitation motor stator (7) corresponding to the magnetic levitation motor rotor (8) is arranged outside the bottom chamber (6); the edge support ring (12) is located in the vacuum chamber (5), the lower end of the cylindrical support ring (11) passes through the bottom of the vacuum chamber (5) and enters the bottom chamber (6), and the bottom of the cylindrical support ring (11) is connected to the magnetic levitation motor rotor (8) through a rotor upper support column (9); a plurality of temperature gauges (10) are arranged at the bottom of the vacuum chamber (5), and the temperature gauges (10) are located inside the cylindrical support ring (11).

10. The internal and external double-positioning support structure of the semiconductor heat treatment equipment according to claim 9, characterized in that, The vacuum chamber (5) is provided with a vacuum pumping port, a wafer transfer port, and a process gas introduction port; a quartz plate (3) is arranged above the vacuum chamber (5), a heating lamp housing (1) is arranged above the quartz plate (3), and a heating lamp (2) is arranged inside the heating lamp housing (1); a reflector (14) is located inside the cylindrical support ring (11), and the bottom of the vacuum chamber (5) also has a reflective annular plate (4), the reflective annular plate (4) is located outside the cylindrical support ring (11), and the reflective annular plate (4) is an annular structure with an inclined angle; the thermometer (10) includes at least one emissivity pyrometer (15).

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