Thermal Field Heat Preservation Component for Film Forming Device and Vertical Film Forming Device

Abstract

The present invention discloses a thermal field heat preservation component for a film forming device and a vertical film forming device. By arranging a combined heat preservation cylinder structure composed of an inner heat preservation cylinder and an outer heat preservation cylinder sleeved on the outer periphery of the thermal field, the peripheral areas of all graphite electrodes connected to all heating elements in the thermal field can be wrapped. The inner heat preservation cylinder can block most of the axially extending areas of each graphite electrode, reducing the heat receiving area of the graphite electrode, thereby reducing the heat loss of the thermal field to the surroundings. The outer heat preservation cylinder can further block the lateral heat transfer of the thermal field, reducing the heat conduction loss of the thermal field to the outside of the vertical film forming device through the metal chamber wall of the reaction chamber. At the same time, by installing an annular heat preservation cover at the top of the thermal field, the heat of the thermal field can be prevented from dissipating upward. The top of the connection between the graphite electrode and the metal electrode is blocked by the outer edge of the annular heat preservation cover, which can effectively avoid the heat dissipation at the connection between the graphite electrode and the metal electrode. The present invention can effectively reduce the influence of the graphite electrode on the temperature rise and temperature distribution of the thermal field.

Description

Technical Field

[0001] The present invention relates to the technical field of film forming, and in particular to a thermal field heat preservation component for a film forming device and a vertical film forming device. Background Art

[0002] In a vertical film forming device, process gas flows downward from the top intake chamber. After being preheated by the upper thermal field, the gas contacts the crystal surface on the lower substrate, is heated to the reaction temperature, and thin film epitaxial growth is carried out. In the existing vertical film forming device, the upper thermal field of the reaction chamber is in the form of multi-zone heating, that is, multiple annular heating elements are arranged in zones from top to bottom. The annular heating elements mostly adopt resistive heating elements, which are successively connected to graphite electrodes and metal electrodes and connected to an external power supply device. During the film forming process, the reaction chamber of the film forming device is in a negative pressure state. The thermal conductivity of the electrode is greater than that of the gas. The heat at the connection and fixation part between the heating element and the graphite electrode is easily conducted outward along the graphite electrode and the metal electrode, resulting in a significantly lower temperature at this part than in other areas, leading to uneven temperature during the film forming process in the reaction chamber, thereby affecting the film forming quality of the wafer.

[0003] Moreover, since the tops of the graphite electrodes connected to different-zone annular heating elements extend upward to the same height at the top of the cavity for fixation, the heated area where the graphite electrodes face the annular heating elements in each zone is relatively large. The heat generated by the annular heating elements will radiate to the surface of the graphite electrode and be transmitted outward, thereby affecting the heating efficiency and temperature distribution uniformity of the thermal field, and ultimately affecting the film forming quality of the wafer. Summary of the Invention

[0004] The purpose of the present invention is to provide a thermal field heat preservation component for a film forming device and a vertical film forming device, which can reduce the influence of the electrode on the heating of the thermal field and the temperature distribution, so as to solve the problems of low heating efficiency of the thermal field and uneven temperature distribution in the reaction chamber existing in the above-mentioned existing vertical film forming device.

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

[0006] The present invention provides a thermal field heat preservation component for a film forming device, including a circular heat preservation cover, an inner heat preservation cylinder sleeved on the outer periphery of the thermal field of the reaction chamber of the film forming device, and an outer heat preservation cylinder sleeved outside the inner heat preservation cylinder, wherein:

[0007] The inner wall of the outer heat insulation cylinder is provided with a plurality of first electrode mounting grooves distributed along its circumferential direction. The top end of any one of the first electrode mounting grooves extends to the top end of the outer heat insulation cylinder, and the top end of the outer heat insulation cylinder is provided with an electrode outlet communicating with the first electrode mounting groove; the bottom ends of different first electrode mounting grooves are respectively arranged corresponding to the annular heating elements at different heights in the heat field, and the bottom end of any one of the first electrode mounting grooves is provided with a step, and the step corresponds to the position where the graphite electrode is connected to the annular heating element at the corresponding height;

[0008] The outer wall of the inner heat insulation cylinder is provided with a plurality of second electrode mounting grooves arranged in one-to-one correspondence with the first electrode mounting grooves, and the second electrode mounting grooves are butted with the corresponding first electrode mounting grooves to form a graphite electrode channel. The top end of any one of the second electrode mounting grooves can block the electrode outlet on the corresponding first electrode mounting groove; the bottom ends of different second electrode mounting grooves respectively extend to the steps of the corresponding first electrode mounting grooves, and the bottom end of each second electrode mounting groove is higher than the step at the corresponding position, so as to form an electrode inlet communicating with the graphite electrode channel between the bottom end of each second electrode mounting groove and the step at the corresponding position; the graphite electrode channel is used for installing a graphite electrode, and one end of the graphite electrode passes through the electrode inlet and is connected to the annular heating element at the corresponding height, and the other end passes through the electrode outlet and is connected to a metal electrode;

[0009] The circular heat insulation cover is arranged on the top of the inner heat insulation cylinder and is coaxially arranged with the inner heat insulation cylinder; the inner diameter of the inner circle of the circular heat insulation cover is smaller than the inner wall diameter of the inner heat insulation cylinder, so as to block the top of the heat field through the inner circle of the circular heat insulation cover, and the outer diameter of the outer circle of the circular heat insulation cover is larger than the outer wall diameter of the outer heat insulation cylinder, so as to block the electrode outlet through the outer circle of the circular heat insulation cover.

[0010] Optionally, the inner wall of the outer heat insulation cylinder is further provided with a limiting boss and a mounting step. The mounting step is located at the top of the outer heat insulation cylinder, and the limiting boss is located below the mounting step;

[0011] The bottom of the inner heat insulation cylinder is arranged on the limiting boss, and the top of the outer wall of the inner heat insulation cylinder is provided with a mounting convex ring matching the mounting step.

[0012] Optionally, the limiting boss is provided with an upward protruding guiding boss; the bottom of the inner heat insulation cylinder is provided with a guiding groove matching the guiding boss.

[0013] Optionally, the lower surface of the inner circle of the circular heat insulation cover is provided with a limiting step matching the inner wall of the inner heat insulation cylinder.

[0014] Optionally, any one of the first electrode mounting grooves is arranged along the axial direction of the outer heat preservation cylinder; any one of the second electrode mounting grooves is arranged along the axial direction of the inner heat preservation cylinder.

[0015] The present invention further provides a vertical film forming device, which is characterized in that it includes a reaction chamber and the heat field heat preservation component for the film forming device as described in any one of the above. In the reaction chamber, an air inlet chamber, a heat field and a base are sequentially arranged from top to bottom. A wafer is placed on the base. The heat field includes a sleeve and a plurality of the annular heating elements sleeved on the outer periphery of the sleeve in sequence from top to bottom. The heat field heat preservation component for the film forming device is sleeved on the outer periphery of the heat field. Graphite electrodes are arranged in all the graphite electrode channels of the heat field heat preservation component for the film forming device, and one end of the graphite electrode passes through the electrode inlet and is connected to the annular heating element at the corresponding height, and the other end of the graphite electrode passes through the electrode outlet and is connected to a metal electrode.

[0016] Optionally, a quartz ring seat is sleeved outside the heat field, and the ends of the graphite electrode and the metal electrode both extend to the upper surface of the quartz ring seat and are connected.

[0017] Optionally, it further includes a reflection cylinder sleeved outside the outer heat preservation cylinder. There is a gap between the outer wall of the reflection cylinder and the cavity wall of the reaction chamber. The top of the reflection cylinder is lapped with the cavity wall of the reaction chamber through a quartz ring. An outer support ring and an inner support ring are sequentially arranged along the radial direction at the bottom of the reflection cylinder. The outer heat preservation cylinder is arranged on the outer support ring. The inner support ring is connected to the outer support ring, and the inner support ring is used to block the bottom of the heat field.

[0018] Optionally, there is a gap between the inner support ring and the sleeve, and the gap communicates with the inner space of the heat field.

[0019] Optionally, a single-sided positioning boss is arranged at the bottom of the outer heat preservation cylinder, and a notch matching the single-sided positioning boss is arranged on the outer support ring.

[0020] The present invention has achieved the following technical effects compared with the prior art:

[0021] In the thermal field heat preservation component for a film forming device disclosed by the present invention, a combined heat preservation cylinder structure composed of an inner heat preservation cylinder and an outer heat preservation cylinder sleeved together is arranged on the outer periphery of the thermal field of the film forming device. A graphite electrode channel 27 corresponding to heat generating bodies at different heights in the thermal field is formed in the side wall sandwich layer of the combined heat preservation cylinder structure, which can wrap the peripheral areas of all graphite electrodes connected to all heat generating bodies in the thermal field. By shielding most of the axially extending areas of each graphite electrode, the inner heat preservation cylinder can reduce the heat receiving area of the graphite electrode, reduce the heat radiated by the heat generating body in the thermal field from being conducted outward through the graphite electrode, and further reduce the loss of thermal field heat to the surroundings. The outer heat preservation cylinder further blocks the lateral transfer of thermal field heat and reduces the loss of thermal field heat through the metal cavity wall of the reaction chamber of the film forming device to the outside of the film forming device. At the same time, the circular heat preservation cover in the above thermal field heat preservation component is arranged on the top of the inner heat preservation cylinder, which can prevent the thermal field heat from dissipating upward and shield the outlet end of the graphite electrode, thereby effectively avoiding the heat loss at the fixed position of the top of the graphite electrode. By arranging the above thermal field heat preservation component for the film forming device on the outer periphery of the thermal field, the present invention can effectively reduce the influence of the graphite electrode on the thermal field temperature rise and temperature distribution, and further solve the problems of low thermal field temperature rise efficiency and uneven temperature distribution in the reaction chamber existing in the existing vertical film forming device.

[0022] In the vertical film forming device disclosed by the present invention, by arranging a combined heat preservation cylinder structure composed of an inner heat preservation cylinder and an outer heat preservation cylinder sleeved together on the outer periphery of the thermal field, the peripheral areas of all graphite electrodes connected to all heat generating bodies in the thermal field can be wrapped. The inner heat preservation cylinder can shield most of the axially extending areas of each graphite electrode, reduce the heat receiving area of the graphite electrode, reduce the heat radiated by the heat generating body from being conducted outward through the graphite electrode, and further reduce the loss of thermal field heat to the surroundings. The outer heat preservation cylinder and the reflection cylinder further block the lateral heat transfer of the thermal field and reduce the loss of thermal field heat through the metal cavity wall of the reaction chamber to the outside of the vertical film forming device. At the same time, by installing a circular heat preservation cover on the top of the thermal field, the thermal field heat can be prevented from dissipating upward, and the top of the connection between the graphite electrode and the metal electrode is shielded by the outer edge of the circular heat preservation cover, which can effectively avoid the heat loss at the connection between the graphite electrode and the metal electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0024] Figure 1 It is a schematic installation diagram of the thermal field heat preservation component inside the reaction chamber of the vertical film forming device disclosed in the embodiment of the present invention;

[0025] Figure 2 Schematic assembly diagram of the upper annular heating element and the thermal field heat preservation component disclosed in the embodiment of the present invention;

[0026] Figure 3 is Figure 2 Enlarged structural diagram at position A in [Figure] (i.e., partial enlarged view of the graphite electrode area of the upper heating element);

[0027] Figure 4 is Figure 2 Enlarged structural diagram at position B in [Figure] (i.e., partial enlarged view of the bottom support of the thermal field heat preservation component);

[0028] Figure 5 Schematic structural diagram of the outer heat preservation cylinder in the thermal field heat preservation component disclosed in the embodiment of the present invention;

[0029] Figure 6 Schematic assembly structure diagram of the inner and outer heat preservation cylinders in the thermal field heat preservation component disclosed in the embodiment of the present invention;

[0030] Figure 7 is Figure 2 Enlarged structural diagram at position C in [Figure] (i.e., partial enlarged view of the positioning structure between the support surface of the outer heat preservation cylinder and the outer support ring);

[0031] Figure 8 Schematic assembly diagram of the lower annular heating element, graphite electrode and thermal field heat preservation component disclosed in the embodiment of the present invention.

[0032] Among them, the reference numerals are:

[0033] 100, vertical film forming device;

[0034] 1, intake chamber; 2, reaction chamber; 3, thermal field; 4, thermal field heat preservation component for film forming device; 5, wafer; 6, base; 7, sleeve; 8, circular heat preservation cover; 9, graphite electrode; 10, quartz ring seat; 11, inner heat preservation cylinder; 12, reflection cylinder; 13, quartz ring; 14, upper annular heating element; 15, middle annular heating element; 16, lower annular heating element; 17, outer heat preservation cylinder; 18, outer support ring; 19, inner support ring; 20, installation surface; 21, limiting surface; 22, electrode inlet; 23, electrode outlet; 24, lower heating element graphite electrode; 25, unilateral positioning boss; 26, metal electrode; 27, graphite electrode channel. Detailed implementation manners

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] One of the objectives of the present invention is to provide a thermal field heat preservation component for a film forming device, which can reduce the influence of electrodes on the thermal field temperature rise and temperature distribution, so as to solve the problems of low thermal field temperature rise efficiency and uneven temperature distribution in the reaction chamber existing in the existing vertical film forming device.

[0037] Another objective of the present invention is also to provide a vertical film forming device having the above-mentioned thermal field heat preservation component for a film forming device.

[0038] To make the above objectives, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Embodiment 1

[0040] As Figures 1 to 3 shown, this embodiment provides a thermal field heat preservation component 4 for a film forming device, including an annular heat preservation cover 8, an inner heat preservation cylinder 11 sleeved on the outer periphery of the thermal field 3 of the reaction chamber 2 of the film forming device, and an outer heat preservation cylinder 17 sleeved outside the inner heat preservation cylinder 11. Among them, a plurality of first electrode installation grooves distributed along the circumferential direction are formed on the inner wall of the outer heat preservation cylinder 17. The top end of any first electrode installation groove extends to the top end of the outer heat preservation cylinder 17, and an electrode outlet 23 communicating with the first electrode installation groove is formed at the top end of the outer heat preservation cylinder 17; the bottom ends of different first electrode installation grooves are respectively arranged corresponding to the annular heating elements at different heights in the thermal field 3. Taking three annular heating elements arranged from top to bottom in the thermal field 3 as an example, as Figure 1 shown, the three annular heating elements from top to bottom are the upper annular heating element 14, the middle annular heating element 15, and the lower annular heating element 16. The connection parts of the upper annular heating element 14, the middle annular heating element 15, and the lower annular heating element 16 with the corresponding graphite electrodes are all located at positions close to the lower edge of the side wall of the heating element. The heights of the graphite electrodes connected to different annular heating elements are different, resulting in different heights of the bottom ends of the corresponding first electrode installation grooves. As Figure 1 shown, the bottom end of the first electrode installation groove corresponding to the upper annular heating element 14 is arranged closest to the top end of the outer heat preservation cylinder 17 compared with the bottom ends of other first electrode installation grooves. As Figure 8As shown, the bottom end of the first electrode mounting groove corresponding to the lower annular heating element 16 is arranged closest to the bottom end of the outer heat insulation cylinder 17 compared to the bottom ends of other first electrode mounting grooves, and the bottom end of the first electrode mounting groove corresponding to the middle annular heating element 15 is located at the middle part of the outer heat insulation cylinder 17. A step is provided at the bottom end of any one of the above-mentioned first electrode mounting grooves, and the step corresponds to the position of the connecting graphite electrode 9 of the annular heating element at the corresponding height. The inner heat insulation cylinder 11 and the outer heat insulation cylinder 17 are coaxially arranged. A plurality of second electrode mounting grooves corresponding to the first electrode mounting grooves one by one are provided on the outer wall of the inner heat insulation cylinder 11, and the second electrode mounting grooves and the corresponding first electrode mounting grooves are butted to form a graphite electrode channel 27. The top end of any one of the second electrode mounting grooves can axially block the electrode outlet 23 on the corresponding first electrode mounting groove; the bottom ends of different second electrode mounting grooves respectively extend to the steps on the corresponding first electrode mounting grooves, and the bottom end of each second electrode mounting groove is higher than the step at the corresponding position, so as to form an electrode inlet 22 communicating with the graphite electrode channel 27 between the bottom end of each second electrode mounting groove and the step at the corresponding position. The graphite electrode 9 is installed in the graphite electrode channel 27, and the lengths of the graphite electrodes 9 installed in the graphite electrode channels 27 with different axial lengths are different. In this specific solution, the bottom end of the graphite electrode 9 passes through the electrode inlet 22 and is connected to the annular heating element at the corresponding height, and the top end of the graphite electrode 9 passes through the electrode outlet 23 and is electrically connected to the corresponding metal electrode 26. The circular heat insulation cover 8 is arranged at the top of the inner heat insulation cylinder 11 and is coaxially arranged with the inner heat insulation cylinder 11. The inner diameter of the inner circle of the circular heat insulation cover 8 is smaller than the inner wall diameter of the inner heat insulation cylinder 11, so that the inner circle of the circular heat insulation cover 8 extends radially inward relative to the inner heat insulation cylinder 11 to form an inner circle shielding ring, which can shield the top of the heat field 3 and reduce the upward transfer of the heat of the heat field 3.

[0041] The outer diameter of the outer circle of the circular heat insulation cover 8 is larger than the outer wall diameter of the outer heat insulation cylinder 17, so that the outer circle of the circular heat insulation cover 8 extends radially outward relative to the outer heat insulation cylinder 17 to form an outer circle shielding ring, which can shield the electrode outlet 23. The above-mentioned heat field heat insulation component 4 for the film forming device is a combined heat insulation structure. The inner and outer heat insulation cylinders cooperate to form a graphite electrode channel 27 to wrap the peripheral area of each graphite electrode 9, and then cooperate with the circular heat insulation cover 8 installed at the top of the heat field 3, so as to achieve the effect of reducing the loss of the heat of the heat field 3 to the surroundings and the top.

[0042] In this embodiment, as Figure 2 、 Figure 3 and Figure 5As shown in the figure, the inner wall of the outer heat preservation cylinder 17 is also provided with a limiting boss and an installation step. Among them, the installation step is located at the top of the outer heat preservation cylinder 17, and the limiting boss is located below the installation step. The installation step and the limiting boss are both circumferentially spaced along the inner wall of the outer heat preservation cylinder 17, and the spaced section is located at the position where the first electrode installation groove is arranged. The end face of the installation step facing the top of the outer heat preservation cylinder 17 is the installation surface 20, and each installation surface 20 is located on the same cross-section. The end face of the limiting boss facing the top of the outer heat preservation cylinder 17 is the limiting surface 21. Due to the different axial lengths of the first electrode installation grooves, different limiting bosses are located at different axial positions on the inner wall of the outer heat preservation cylinder 17. Correspondingly, during assembly, the bottom end face of the inner heat preservation cylinder 11 is arranged on the limiting surface 21 of the limiting boss, and the limiting boss axially positions and supports the inner heat preservation cylinder 11. An installation convex ring matching the installation step is arranged at the top of the outer wall of the inner heat preservation cylinder 11. When the bottom end face of the inner heat preservation cylinder 11 abuts against the limiting surface 21, the installation convex ring just fits into the installation step, and the installation convex ring abuts against the installation surface 20 of the installation step.

[0043] In this embodiment, as Figure 2 , Figure 3 , Figure 5 and Figure 6 shown, the above-mentioned limiting boss is also provided with a guiding boss protruding axially upward, and a guiding groove matching the guiding boss is opened at the bottom of the inner heat preservation cylinder 11. Generally, the guiding boss is arranged at the bottom end of the first electrode installation groove corresponding to the top annular heating element. The guiding boss matches the guiding groove at the bottom of the inner heat preservation cylinder 11, and can perform installation guiding and positioning on the inner heat preservation cylinder 11 and the outer heat preservation cylinder 17, avoiding relative rotation between the inner heat preservation cylinder 11 and the outer heat preservation cylinder 17.

[0044] In this embodiment, a limiting step matching the inner wall of the inner heat preservation cylinder 11 is arranged on the lower surface of the inner ring of the circular heat preservation cover 8. The limiting step is circular. During installation, it is embedded into the inner heat preservation cylinder 11 to limit the circumferential direction of the circular heat preservation cover 8 and prevent the circular heat preservation cover 8 from shifting relative to the inner heat preservation cylinder 11.

[0045] In this embodiment, it is preferred that any one of the first electrode installation grooves is arranged along the axial direction of the outer heat preservation cylinder 17, and any one of the second electrode installation grooves is arranged along the axial direction of the inner heat preservation cylinder 11. Thus, each graphite electrode channel 27 formed between the outer heat preservation cylinder 17 and the inner heat preservation cylinder 11 is also arranged along the axial directions of the inner heat preservation cylinder 11 and the outer heat preservation cylinder 17. The following combines specific examples to specifically illustrate the installation method and use principle of the above-mentioned combined heat preservation structure in this embodiment:

[0046] The above-mentioned combined heat-insulating structure of this embodiment is sleeved outside the heat field 3 formed by sequentially arranging the upper annular heating element 14, the middle annular heating element 15, and the lower annular heating element 16 from top to bottom. The inner heat-insulating cylinder 11 is installed from top to bottom and nested with the outer heat-insulating cylinder 17. The outer wall surface of the inner heat-insulating cylinder 11 is attached to the inner wall surface of the outer heat-insulating cylinder 17, and the inner heat-insulating cylinder 11 and the outer heat-insulating cylinder 17 are axially positioned through the mounting surface 20 and the limiting surface 21. As Figure 5 shown, the outer wall of the outer heat-insulating cylinder 17 is a cylindrical straight barrel, and the inner wall is provided with first electrode mounting grooves with different axial extension lengths based on the installation positions of the upper, middle, and lower multi-zone heating elements and the graphite electrode 9. As Figure 6 shown, the inner wall of the inner heat-insulating cylinder 11 is a cylindrical straight barrel, and the outer wall is provided with second electrode mounting grooves arranged in one-to-one correspondence with the first electrode mounting grooves. The bottom is provided with guiding grooves with different heights (or called axial extension lengths) to correspond to the steps at the bottoms of different first electrode mounting grooves. Among them, the second electrode mounting grooves and the guiding grooves are arranged in one-to-one correspondence, and the bottom end of each second electrode mounting groove is connected to the corresponding guiding groove. The electrode inlet 22 is formed between the step and the connecting junction of the second electrode mounting groove and the guiding groove. A graphite electrode channel 27 is arranged in the inner layer of the combined cylindrical structure formed by overlapping the inner and outer heat-insulating cylinders. As Figure 6 shown, the electrode inlet 22 is located on the inner wall of the combined cylindrical structure, and the electrode inlet 22 corresponds to the installation heights of each zone of heating elements respectively; a plurality of electrode outlets 23 are located at the top of the combined cylindrical structure and are evenly distributed in a circle.

[0047] Each graphite electrode channel 27 in the combined heat-insulating structure is bent multiple times along its axis. Correspondingly, the graphite electrode 9 in each graphite electrode channel 27 is also bent in accordance with the bending structure of the graphite electrode channel 27. As Figure 2As shown, taking the graphite electrode channel 27 corresponding to the upper annular heating element 14 as an example, the bottom end of the graphite electrode channel 27 is bent radially inward along the step of the first electrode mounting groove at the step of the combined heat-insulating structure, and the top end is bent radially outward between the electrode outlet 23 and the circular heat-insulating cover 8 along the combined heat-insulating structure, and the whole is approximately in a "Z" shape. Correspondingly, the graphite electrode 9 is also bent in a "Z" shape within the graphite electrode channel 27. By setting the whole graphite electrode channel 27 as the above-mentioned "Z" shape, it can not only ensure that both ends of the graphite electrode 9 penetrate the graphite electrode channel 27 and are respectively connected to the corresponding heating element and the metal electrode 26, but also utilize the nested structure of the inner and outer heat-insulating cylinders to form a staggered shield at the electrode inlet and outlet of the graphite electrode channel 27, effectively preventing the heat of the heat field 3 from diffusing along the installation channel of the graphite electrode 9. In this specific solution, the connection methods and structures of both ends of the graphite electrode 9 connected to the heating elements at different heights in the heat field 3 are consistent, and the distances extended radially along the combined heat-insulating structure are also the same. Only the distances extended axially along the combined heat-insulating structure are significantly different due to the different installation heights of the heating elements. For example, Figure 8 as shown, the axial extension length of the graphite electrode connected to the lower annular heating element 16, that is, the lower heating element graphite electrode 24, is significantly longer than that of the graphite electrode 9 connected to the upper annular heating element 14 as shown in Figure 2 and so on. The axial extension length of the graphite electrode 9 connected to the middle annular heating element 15 is between the axial extension length of the graphite electrode 9 connected to the lower annular heating element 16 and the axial extension length of the graphite electrode 9 connected to the upper annular heating element 14. In this embodiment, the top ends of each graphite electrode 9 all extend to the surface of the quartz ring seat 10 in the vertical film-forming device for unified fixation.

[0048] A quartz ring 13 is installed at the upper step of the reaction chamber cavity of the vertical film-forming device 100. A reflection cylinder 12 with an installation step is placed on the quartz ring 13. The main body of the reflection cylinder 12 is located inside the reaction chamber cavity and there is a certain gap between it and the cavity inner wall. The inner support ring 19 and the outer support ring 18 are successively installed at the lower end of the reflection cylinder 12 from the inside to the outside, which are used to support the combined cylinder structure formed by the nested inner and outer heat-insulating cylinders above, and at the same time play the role of separating the reaction chamber interlayer up and down. As shown in Figure 1 the above-mentioned heat field 3 and the combined cylinder structure are both installed in the upper part of this interlayer. The inner support ring 19 and the outer support ring 18 also play a certain heat-insulating effect on the heat field to reduce the diffusion of the heat of the heat field 3 to the lower part of the interlayer. When the whole combined cylinder structure is installed, it penetrates downward into the reaction chamber cavity of the vertical film-forming device 100, and the outer heat-insulating cylinder 17, the inner heat-insulating cylinder 11 and the circular heat-insulating cover 8 are installed in sequence. As shown in Figure 4 the bottom end surface of the outer heat-insulating cylinder 17 is in direct contact with the outer support ring 18. As shown in Figure 7As shown in the figure, a single-sided positioning boss 25 is provided at the bottom end of the outer heat preservation cylinder 17 as a positioning structure corresponding to the notch on the upper supporting surface of the outer support ring 18, so as to circumferentially limit the outer heat preservation cylinder 17 and prevent the combined cylinder structure from shifting relative to the reaction chamber cavity of the vertical film forming device 100.

[0049] After installing the above-mentioned combined cylinder structure of this embodiment, that is, the heat transfer trend in the reaction chamber cavity of the vertical film forming device 100 of the heat field heat preservation component 4 for the film forming device is as follows:

[0050] In the heat field 3, the inner heating surfaces of the upper, middle and lower annular heating elements face the wall of the sleeve 7 of the reaction chamber cavity, and the heat emitted by the outer heating surfaces is transferred outwards. The inner heat preservation cylinder 11 is located between the sleeve 7 and the graphite electrode 9, and can shield most areas of all the graphite electrodes 9 in the vertical film forming device 100, reduce the heating area of the graphite electrodes 9, and reduce the heat radiated by the upper, middle and lower annular heating elements from being conducted outwards through the corresponding graphite electrodes 9. The settings of the outer heat preservation cylinder 17 and the reflection cylinder 12 further block the lateral (i.e., radial) heat transfer of the heat field 3, and reduce the heat loss through the reaction chamber wall to the outside. The circular heat preservation cover 8 is installed above the fixed end of the graphite electrode 9 and the entire heat field 3, and can effectively reduce the upward heat transfer of the heat field 3.

[0051] It can be seen that the heat field heat preservation component 4 for the film forming device of this technical solution, by being arranged on the outer periphery of the heat field 3 of the film forming device, can wrap the peripheral areas of all the graphite electrodes 9 connected to all the heating elements in the heat field 3. The inner heat preservation cylinder 11 can reduce the heating area of the graphite electrodes 9 by shielding most of the axially extended areas of each graphite electrode 9, reduce the heat radiated by the heating elements in the heat field from being conducted outwards through the graphite electrodes 9, and further reduce the heat loss of the heat field 3 to the surroundings; the outer heat preservation cylinder 17 and the reflection cylinder 12 further block the lateral heat transfer of the heat field 3, and reduce the heat loss of the heat field 3 through the metal chamber wall of the reaction chamber 2 to the outside of the film forming device. At the same time, the circular heat preservation cover 8 of the heat field heat preservation component 4 for the film forming device, by being arranged on the top of the inner heat preservation cylinder 11, can prevent the heat of the heat field 3 from dissipating upwards, and shield the top of the connection between the graphite electrode 9 and the metal electrode 26, thereby effectively avoiding the heat dissipation at the connection between the graphite electrode 9 and the metal electrode 26, which is also the fixed part at the top end of the graphite electrode 9. By arranging the heat field heat preservation component 4 for the film forming device on the outer periphery of the heat field 3, this technical solution can effectively reduce the influence of the graphite electrodes on the heat field heating and temperature distribution, and further solve the problems of low heat field heating efficiency and uneven temperature distribution in the reaction chamber existing in the existing vertical film forming device.

[0052] Embodiment 2

[0053] As Figure 1As shown in the figure, this embodiment provides a vertical film-forming device 100, which includes a reaction chamber 2 and a thermal field heat-insulating component 4 for the film-forming device disclosed in Embodiment 1. Inside the reaction chamber 2, an air inlet chamber 1, a thermal field 3, and a base 6 are sequentially arranged from top to bottom. A wafer 5 is placed on the base 6. The thermal field 3 includes a sleeve 7 and a plurality of annular heating elements sleeved on the outer periphery of the sleeve in sequence from top to bottom. The thermal field heat-insulating component 4 for the film-forming device is sleeved on the outer periphery of the thermal field 3. Graphite electrodes 9 are arranged in all the graphite electrode channels of the thermal field heat-insulating component 4 for the film-forming device. The bottom end of the graphite electrode 9 is bent and passes through the electrode inlet 22 to be connected to the annular heating element at the corresponding height, and the top end of the graphite electrode is bent and passes through the electrode outlet 23 to be electrically connected to the metal electrode 26.

[0054] In this embodiment, as Figures 1 to 3 shown, a quartz ring seat 10 is sleeved outside the thermal field 3, and the ends of the graphite electrode 9 and the metal electrode 26 both extend to the upper surface of the quartz ring seat 10 and are connected.

[0055] In this embodiment, it further includes a reflection cylinder 12 sleeved outside the outer heat-insulating cylinder 17. There is a gap between the outer wall of the reflection cylinder 12 and the cavity wall of the reaction chamber 2. The top of the reflection cylinder 12 is lapped with the cavity wall of the reaction chamber 2 through a quartz ring 13. An outer support ring 18 and an inner support ring 19 are sequentially arranged along the radial direction at the bottom of the reflection cylinder 12. The outer heat-insulating cylinder 17 is arranged on the outer support ring 18, and the inner support ring 19 is connected to the outer support ring 18. The inner support ring 19 can block the bottom of the thermal field 3, and there is a gap between the inner support ring 19 and the sleeve 7, and this gap communicates with the inside of the sleeve 7. The above-mentioned inner support ring 19 and outer support ring 18 can both block most of the heat of the thermal field 3 from being transferred into the reaction chamber 2 to avoid too high a temperature in the air inlet chamber 1, and at the same time allow a small part of the heat of the upper thermal field 3 to be transferred downward, achieving the effect of assisting in heating the outer ring area of the wafer 5.

[0056] In this embodiment, as Figure 7 shown, a single-sided positioning boss 25 is provided at the bottom end of the outer heat-insulating cylinder 17 as a positioning structure corresponding to the notch on the upper support surface of the outer support ring 18 to perform circumferential positioning on the outer heat-insulating cylinder 17 and prevent the combined cylinder structure from shifting relative to the reaction chamber cavity of the vertical film-forming device 100.

[0057] In the above-mentioned vertical film-forming device 100, the air inlet chamber 1 is located at the top of the reaction chamber 2, stably providing raw material gas to the inside of the reaction chamber 2 cavity. The gas is preheated by the thermal field 3 and then flows downward along the internal flow channel of the sleeve 7 to contact and react with the wafer 5 on the surface of the base 6 for epitaxial growth. The thermal field 3 above the base 6 includes a plurality of annular heating elements arranged in sequence from top to bottom. Each annular heating surface evenly heats the sleeve 7, and a thermal field heat-insulating component 4 for the film-forming device is installed in the outer area of the thermal field 3 to block the graphite electrode 9 to reduce heat loss.

[0058] As can be seen, in the vertical film forming device 100 of the present technical solution, by arranging a combined heat preservation cylinder structure composed of an inner and an outer heat preservation cylinder sleeved outside the heat field 3, the peripheral areas of all graphite electrodes 9 connected to all heating elements in the heat field 3 can be wrapped. The inner heat preservation cylinder 11 can block most of the axially extending areas of each graphite electrode 9, reducing the heat receiving area of the graphite electrode 9 and reducing the heat radiated by the heating element from being conducted outward through the graphite electrode 9, thereby reducing the heat loss of the heat field 3 to the surroundings; the outer heat preservation cylinder 17 and the reflection cylinder 12 further block the lateral heat transfer of the heat field 3, reducing the heat loss of the heat field through the metal cavity wall of the reaction chamber 2 to the outside of the vertical film forming device 100. At the same time, by installing an annular heat preservation cover 8 at the top of the heat field 3, the heat dissipation of the heat field 3 upward can be avoided, and the top of the connection between the graphite electrode 9 and the metal electrode 26 is blocked by the outer edge of the annular heat preservation cover 8, which can effectively avoid the heat dissipation at the connection between the graphite electrode 9 and the metal electrode 26, which is also the fixed part of the top end of the graphite electrode 9.

[0059] In summary, by arranging a heat field heat preservation component for the film forming device outside the heat field in the present technical solution, the influence of the graphite electrode on the heat field temperature rise and temperature distribution can be effectively reduced, thereby solving the problems of low heat field temperature rise efficiency and uneven temperature distribution in the reaction chamber existing in the existing vertical film forming device.

[0060] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claimed claims.

[0061] In the present invention, specific examples are used to elaborate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A thermal field heat preservation component for a film forming device, characterized in that, It includes an annular heat preservation cover (8), an inner heat preservation cylinder (11) sleeved on the outer periphery of the heat field (3) of the film forming device reaction chamber, and an outer heat preservation cylinder (17) sleeved outside the inner heat preservation cylinder (11), wherein: a plurality of first electrode installation grooves distributed along the circumferential direction of the outer heat preservation cylinder (17) are formed on the inner wall of the outer heat preservation cylinder (17), the top end of any one of the first electrode installation grooves extends to the top end of the outer heat preservation cylinder (17), and an electrode outlet (23) communicating with the first electrode installation groove is formed at the top end of the outer heat preservation cylinder (17); the bottom ends of different first electrode installation grooves are respectively arranged corresponding to the annular heating elements at different heights in the heat field (3), and a step is arranged at the bottom end of any one of the first electrode installation grooves, and the step corresponds to the position of the connecting graphite electrode (9) of the annular heating element at the corresponding height; A plurality of second electrode installation grooves corresponding to the first electrode installation grooves one by one are arranged on the outer wall of the inner heat preservation cylinder (11), and the second electrode installation groove and the corresponding first electrode installation groove are butted to form a graphite electrode channel (27). The top end of any one of the second electrode installation grooves can block the electrode outlet (23) on the corresponding first electrode installation groove; the bottom ends of different second electrode installation grooves respectively extend to the steps of the corresponding first electrode installation grooves, and the bottom end of each second electrode installation groove is higher than the step at the corresponding position, so as to form an electrode inlet (22) communicating with the graphite electrode channel (27) between the bottom end of each second electrode installation groove and the step at the corresponding position; the graphite electrode (9) is installed in the graphite electrode channel (27), one end of the graphite electrode (9) passes through the electrode inlet (22) and is connected to the annular heating element at the corresponding height, and the other end passes through the electrode outlet (23) and is connected to the metal electrode (26); The annular heat preservation cover (8) is arranged on the top of the inner heat preservation cylinder (11) and is coaxially arranged with the inner heat preservation cylinder (11); the inner diameter of the inner ring of the annular heat preservation cover (8) is smaller than the inner wall diameter of the inner heat preservation cylinder (11), so as to block the top of the heat field (3) through the inner ring of the annular heat preservation cover (8), and the outer diameter of the outer ring of the annular heat preservation cover (8) is larger than the outer wall diameter of the outer heat preservation cylinder (17), so as to block the electrode outlet (23) through the outer ring of the annular heat preservation cover (8).

2. The thermal field heat preservation component for a film forming device according to claim 1, characterized in that, A limiting boss and an installation step are further arranged on the inner wall of the outer heat preservation cylinder (17), the installation step is located at the top of the outer heat preservation cylinder (17), and the limiting boss is located below the installation step; The bottom of the inner heat preservation cylinder (11) is arranged on the limiting boss, and an installation convex ring matching with the installation step is arranged at the top of the outer wall of the inner heat preservation cylinder (11).

3. The thermal field heat preservation component for a film forming device according to claim 2, characterized in that, A guiding boss protruding upward is arranged on the limiting boss; a guiding groove matching with the guiding boss is formed at the bottom of the inner heat preservation cylinder (11).

4. The thermal field heat preservation component for a film forming device according to any one of claims 1 to 3, characterized in that, A limiting step matching with the inner wall of the inner heat preservation cylinder (11) is arranged on the lower surface of the inner ring of the annular heat preservation cover (8).

5. The thermal field heat preservation component for a film forming device according to any one of claims 1 to 3, characterized in that, Any one of the first electrode mounting grooves is arranged along the axial direction of the outer heat insulation cylinder (17); any one of the second electrode mounting grooves is arranged along the axial direction of the inner heat insulation cylinder (11).

6. A vertical film forming device, characterized in that, It includes a reaction chamber (2) and a thermal field heat insulation assembly (4) for a film forming device as described in any one of claims 1 to 5. An air inlet chamber (1), a thermal field (3), and a base (6) are sequentially arranged in the reaction chamber (2) from top to bottom. A wafer (5) is placed on the base (6). The thermal field (3) includes a sleeve (7) and a plurality of annular heating elements sleeved on the outer periphery of the sleeve (7) in sequence from top to bottom. The thermal field heat insulation assembly (4) for the film forming device is sleeved on the outer periphery of the thermal field (3). Graphite electrodes (9) are arranged in all the graphite electrode channels (27) of the thermal field heat insulation assembly (4) for the film forming device. One end of the graphite electrode (9) passes through the electrode inlet (22) and is connected to the annular heating element at the corresponding height, and the other end of the graphite electrode (9) passes through the electrode outlet (23) and is connected to a metal electrode (26).

7. The vertical film forming device according to claim 6, characterized in that, A quartz ring seat (10) is sleeved outside the thermal field (3). The ends of the graphite electrode (9) and the metal electrode (26) extend to the upper surface of the quartz ring seat (10) and are connected.

8. The vertical film forming device according to claim 6, characterized in that, It further includes a reflection cylinder (12) sleeved outside the outer heat insulation cylinder (17). There is a gap between the outer wall of the reflection cylinder (12) and the cavity wall of the reaction chamber (2). The top of the reflection cylinder (12) is lapped with the cavity wall of the reaction chamber (2) through a quartz ring (13). An outer support ring (18) and an inner support ring (19) are sequentially arranged at the bottom of the reflection cylinder (12) along its radial direction. The outer heat insulation cylinder (17) is arranged on the outer support ring (18). The inner support ring (19) is connected to the outer support ring (18). The inner support ring (19) is used to block the bottom of the thermal field (3).

9. The vertical film forming device according to claim 8, characterized in that, There is a gap between the inner support ring (19) and the sleeve (7), and the gap is communicated with the internal space of the thermal field (3).

10. The vertical film forming device according to claim 8, characterized in that, A single-sided positioning boss (25) is arranged at the bottom of the outer heat insulation cylinder (17), and a notch matching the single-sided positioning boss (25) is arranged on the outer support ring (18).

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