A graphite boat with uniform temperature distribution

Abstract

The present invention discloses a graphite boat with uniform temperature distribution, which relates to the technical field of PECVD coating of photovoltaic cells, and comprises a boat body for carrying silicon wafers, the boat body is composed of a plurality of outer boat pages and inner boat pages which are arranged in parallel and installed at intervals, the outer boat pages have the same structure as the inner boat pages, micropores are provided on the surface of the inner boat pages, and the distribution density of the micropores gradually increases from the center of the inner boat pages to both ends, and a heat dissipation channel is provided through the surface of the inner boat pages and near the bottom. The graphite boat with uniform temperature distribution can adjust the heating power of each structural component of the heat conduction mechanism according to the monitoring result of the thermocouple in real time, realize the automatic adjustment and balancing function of the pad temperature of the furnace mouth and furnace tail of the boat body, realize the balanced distribution of temperature, can store and release heat energy by itself, make the temperature distribution more uniform, and improve the consistency and quality of silicon wafer coating.

Description

Technical Field

[0001] The invention relates to the technical field of PECVD coating of photovoltaic cells, in particular to a graphite boat with uniform temperature distribution. Background Art

[0002] Graphite boat is an important carrier used in the production process of solar cells. Its structure mainly includes multiple boats with a certain interval. Silicon wafers are attached to both sides of these boats. During the coating process, two adjacent boats will form positive and negative electrodes. Through glow discharge, SiH4 and NH3 gases are ionized, and then a SixNy film layer is formed on the surface of the silicon wafer to achieve the coating purpose. In the production process of solar cells, the graphite boat is a key component for carrying silicon wafers for PECVD process. Its structural design directly affects the quality and efficiency of silicon wafer coating. Especially in the process of silicon wafer processing under high temperature environment, the traditional graphite boat is often used in PECVD process. Due to the large graphite composite pad structure at the furnace mouth and furnace tail of the graphite boat, the temperature field distribution is often uneven, resulting in stress and defects in the silicon wafer during the heat treatment process, which causes uneven coating thickness, affects the quality and uniformity of the coating, and further affects the performance and yield of semiconductor devices. Summary of the invention

[0003] In order to solve the above technical problems, the present invention is implemented through the following technical solutions: a graphite boat with uniform temperature distribution, including a boat body for carrying silicon wafers, the boat body is composed of a plurality of outer boat pages and inner boat pages arranged in parallel and installed at intervals to ensure uniform distribution of hot air flow, the outer boat pages have the same structure as the inner boat pages, the surface of the inner boat pages is provided with micropores, and the distribution density of the micropores gradually increases from the center of the inner boat pages to both ends to promote the flow of hot air and achieve more uniform temperature distribution, the surface of the inner boat pages and near the bottom are provided with heat dissipation channels, and the heat dissipation channels are provided at equal intervals along the long side edges of the inner boat pages, the heat dissipation channels are connected to the bottom of the boat body to improve the heat dissipation efficiency and keep the temperature of the graphite boat stable, the outer boat pages and the inner boat pages are jointly provided with first ceramic rods in a linear array, and the first ceramic rods are installed in a linear array along the long side edges of the inner boat pages;

[0004] Graphite pads are used to keep the distance between the outer ship leaf and the inner ship leaf. The graphite pads have a pair of front pads installed at the furnace mouth and a rear pad installed at the furnace tail. The front pads and the rear pads have the same structure. The front pads include a first pad group and a second pad group, and the first pad group is installed above the second pad group through the boat body. The outer ship leaf is installed in parallel and alternately with the inner ship leaf through the first pad group and the second pad group.

[0005] A temperature balancing system is used to heat and control the temperature of the boat body. The temperature balancing system includes a heat conducting mechanism, a thermocouple and a control unit. The heat conducting mechanism includes a heat conducting part, a first electric heating wire ring and a second electric heating wire ring. The heat conducting part is embedded and installed on the top of the boat body. The heat conducting part is installed on the top between the outer hull and the inner hull. The first electric heating wire ring is installed inside the first pad block group and the second pad block group. The second electric heating wire ring is installed on the left and right sides of the first electric heating wire ring. The heating assembly is used to heat the graphite pad block, wherein the heat conducting mechanism is used to balance the temperature of various areas in the boat body.

[0006] Preferably, the thermocouples are inserted into the first pad block group in a vertically symmetrical manner, and the second pad block group is also equipped with a thermocouple, the thermocouples are used to monitor the temperature of the surface of the boat body in real time, the thermocouples transmit the monitored temperature data to the control unit, the control unit is connected to the thermocouple and the heat conducting mechanism, and is used to adjust the heat conducting effect of the heat conducting mechanism according to the monitoring results of the thermocouples, that is, thermocouples are evenly arranged on the graphite pads at the furnace mouth and the furnace tail, and the temperature of each area can be monitored in real time.

[0007] Preferably, the control unit includes a microprocessor and an execution unit. The microprocessor receives data transmitted by the thermocouple and performs calculations. If it is found that the temperature deviation in a certain area is large, the execution unit is controlled to adjust the thermal power effect of the heat conduction mechanism to achieve a balanced temperature distribution.

[0008] Preferably, a second ceramic rod and a carbon fiber rod are embedded and installed inside the first pad block group, the second ceramic rod is installed side by side on the left side of the carbon fiber rod through the first pad block group, and a support is installed on the bottom of the second pad block group in a front-to-back symmetrical shape. The outer ship leaf on the boat body is assembled with the inner ship leaf through the first ceramic rod, the second ceramic rod, the carbon fiber rod, the heating assembly, the thermocouple and the second electric heating wire ring.

[0009] Preferably, a heat dissipation channel is opened on the surface of the inner ship leaf near the bottom, and the heat dissipation channels are opened at equal intervals along the long side edges of the inner ship leaf. The second pad block group is composed of a pressure regulating pad and a square pad through a second ceramic rod, a carbon fiber rod, a heating assembly, a thermocouple and a second electric heating wire ring.

[0010] Preferably, the first pad group includes a pair of terraced pads, a pair of pressure-regulating pads are installed between the pair of terraced pads, and a pair of square pads are installed between the pair of pressure-regulating pads, and the pressure-regulating pads are installed between the terraced pads and the square pads, and the carbon fiber rod and the second ceramic rod are arranged side by side and pass through the terraced pads, the pressure-regulating pads and the square pads in sequence.

[0011] Preferably, the front and rear surfaces of the terraced pad, the pressure-regulating pad and the square pad are vertically symmetrically provided with cavities for connecting the pad structures to which the graphite pad belongs to facilitate heat transfer. The front and rear sides of the top of the support member are fixedly connected with semi-columns, and the support member is inserted into the square pad through the cooperation of the semi-columns and the cavities. The pressure-regulating pad is provided with a pressure-regulating seam in a centrally symmetrical shape, which can adjust the interval between the ship leaf structures of the boat body within a small range, and provide a certain expandable range for the thermal expansion of the ship leaf.

[0012] Preferably, the square gasket includes a pair of external gaskets, a pair of internal gaskets are installed between the pair of external gaskets, square grooves are opened on the wall surfaces of the external gaskets and the internal gaskets in the same direction, and convex tube sleeves are fixedly connected to the corners of the wall surfaces of the external gaskets and the internal gaskets in the same direction, and the internal gaskets are inserted with the external gaskets through the convex tube sleeves, wherein the middle parts of the square grooves of the external gaskets and the internal gaskets are opened with groove cavities.

[0013] Preferably, a phase change material block and a heat conductive sheet are installed between the external pad and the internal pad, and the temperature distribution is balanced by utilizing the heat absorption and release characteristics of the phase change material. Specifically, the phase change material absorbs heat when the temperature rises, and releases heat when the temperature drops, thereby balancing the temperature of each area, and the heat conductive sheet is installed between the phase change material block and the external pad, and a three-dimensional sheet is fixedly connected to the middle of one side of the heat conductive sheet facing the external pad, and the three-dimensional sheet is installed by being embedded with the external pad through a groove cavity opened in the square groove, and the phase change material block and the heat conductive sheet are adhered and embedded together in the square groove of the external pad, wherein, by designing a heat conductive sheet inside the graphite pad, the heat of each area is evenly conducted to assist the phase change material in achieving temperature balance.

[0014] Preferably, the heat conducting component comprises a heat conducting pipe, which is installed at the top between the outer ship leaf and the inner ship leaf, and the heat conducting liquid is contained inside the heat conducting pipe to enhance the heat conducting effect, an aluminum hoop is fixedly installed on the surface of the heat conducting pipe near the boat body, and the aluminum hoop is clamped with the first ceramic rod, a heat conducting plate is fixedly connected to the surface of the heat conducting pipe near the boat body, the heat conducting plate is installed between two adjacent aluminum hoop sleeves, and the heat conducting plates are evenly distributed between the outer ship leaf and the inner ship leaf, the heat conducting plate is made of high thermal conductivity material, and phase change material is embedded and installed on the surface of the heat conducting plate, and the heat conducting pipe connects the heat conducting plates together to form a complete heat conducting network.

[0015] The present invention provides a graphite boat with uniform temperature distribution, which has the following beneficial effects:

[0016] 1. The graphite boat with uniform temperature distribution realizes balanced temperature distribution inside and outside the boat through the optimized design of heat conduction mechanism and the thermocouple as temperature sensor, which can accurately monitor the temperature, thereby reducing the stress and defects of silicon wafers during heat treatment and improving product quality and yield. The phase change material can absorb or release a large amount of heat when the temperature changes, thereby further balancing the temperature distribution inside the boat.

[0017] Second, the graphite boat with uniform temperature distribution has a structural design in which the pad structures belonging to the first pad group and the second pad group are composed of phase change material blocks and heat conducting plates as well as internal and external pad structures. Each pad structure is composed of heat conducting materials and phase change materials as a whole, which can guide and transfer the heat energy between the pad structures and balance the temperature between the graphite pads by utilizing the characteristics of the phase change material that absorbs heat when the temperature rises and releases heat when the temperature drops, thereby assisting in balancing the temperature of the boat body, thereby establishing a structural control basis for balancing the temperature to ensure the uniformity of the coating thickness and the quality of the coating.

[0018] 3. The graphite boat with uniform temperature distribution has microporous structures on the surfaces of the outer and inner leaves, and utilizes a structural design in which the density of microporous distribution gradually increases from the center of the leaves to both ends, so as to promote the flow of hot air and achieve a more uniform temperature distribution. In addition, the heat dissipation channels are provided on the bottom of the surfaces of the outer and inner leaves, so that the bottoms of the leaf structures of the boat body are connected to each other, thereby improving the heat dissipation efficiency and maintaining the temperature of the graphite boat stable. With the combined effects of these two structural designs, the graphite boat itself has a basic operating structure that can ensure that its own temperature is balanced, and can provide an excellent structural control basis for the temperature balance system to balance the temperature of the boat body, provide effective constant temperature control conditions, and play an auxiliary role in the temperature balance system to easily regulate the temperature of the boat body to quickly balance the temperature.

[0019] Fourth, the graphite boat with uniform temperature distribution uses thermocouples to monitor the temperature of the pad structure of the boat body near the furnace mouth and the furnace tail in real time, and transmits the monitored temperature data to the control unit through the thermocouples. The control unit is connected with the thermocouple and the heat conducting mechanism to adjust the heating power of each structural component of the heat conducting mechanism in real time according to the monitoring results of the thermocouple. The output power of the heat conducting part, the first electric heating wire ring and the second electric heating wire ring can be adjusted respectively, and the heat conducting effect of the heat conducting mechanism can be changed, so as to realize the automatic adjustment and balancing function of the pad temperature of the furnace mouth and the furnace tail of the boat body and realize the balanced distribution of temperature.

[0020] 5. The graphite boat with uniform temperature distribution can solve the problem of uneven temperature field distribution caused by the presence of large graphite composite pad structures at the furnace mouth and furnace tail of the traditional graphite boat during PECVD. It can eliminate the uneven coating thickness caused by stress and defects in the silicon wafer during the heat treatment process, and enable the graphite boat to automatically adjust and balance the pad temperatures at the furnace mouth and furnace tail, achieve balanced temperature distribution on the graphite boat, and store and release heat energy by itself, making the temperature distribution more uniform, thereby improving the consistency and quality of silicon wafer coating, thereby improving the performance and yield of semiconductor devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the external structure of a graphite boat with uniform temperature distribution according to the present invention;

[0022] Figure 2 It is a left side view of a graphite boat with uniform temperature distribution according to the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the outer ship page of the present invention;

[0024] Figure 4 It is a structural schematic diagram of the inner ship page of the present invention;

[0025] Figure 5 It is a structural schematic diagram of the first cushion block group of the present invention;

[0026] Figure 6 is a structural schematic diagram of the second cushion block group of the present invention;

[0027] Figure 7 It is a schematic diagram of the partial assembly structure of the first pad block group and the heating assembly of the present invention;

[0028] Figure 8 It is a schematic diagram of the disassembled structure of the support member and the second cushion block group of the present invention;

[0029] Fig. 9 This is a schematic diagram of the overall disassembled structure of the square pad of the present invention;

[0030] Fig.10 It is a schematic diagram of the disassembled structure of the phase change material block and the heat conducting sheet on the external pad of the present invention;

[0031] Fig.11 It is a schematic diagram of the disassembled structure of the heat conducting sheet and the external spacer block of the present invention;

[0032] Fig.12 It is a right side view of the first cushion block group of the present invention;

[0033] Fig.13 It is a right side view of the second cushion block assembly of the present invention;

[0034] Fig.14 It is a schematic structural diagram of the heat conducting member of the present invention.

[0035] In the figure: 1, outer ship leaf; 2, inner ship leaf; 3, first pad block group; 4, second pad block group; 5, heat conductor; 6, first ceramic rod; 7, second ceramic rod; 8, carbon fiber rod; 9, first electric heating wire ring; 10, support member; 11, semi-column; 12, thermocouple; 13, second electric heating wire ring; 21, heat dissipation channel; 31, terraced pad; 32, voltage regulating pad; 33, square pad; 34, cavity; 35, phase change material block; 36, heat conductive sheet; 37, three-dimensional sheet; 331, external pad; 332, internal pad; 333, convex pipe sleeve; 334, groove cavity; 51, heat pipe; 52, aluminum hoop sleeve; 53, heat conductive plate. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0037] The first embodiment, as Figures 1 to 14 As shown, the present invention provides a technical solution: a graphite boat with uniform temperature distribution, including a boat body for carrying silicon wafers, the boat body is composed of a plurality of outer boat pages 1 and inner boat pages 2 installed in parallel and at intervals to ensure uniform distribution of hot air flow, the outer boat pages 1 and the inner boat pages 2 have the same structure, micropores are opened on the surface of the inner boat pages 2, and the distribution density of the micropores gradually increases from the center of the inner boat pages 2 to both ends to promote the flow of hot air and achieve more uniform temperature distribution, a heat dissipation channel 21 is opened on the surface of the inner boat pages 2 and near the bottom, and the heat dissipation channel 21 is opened at equal intervals along the long edge direction of the inner boat pages 2, and the heat dissipation channel 21 is communicated with the bottom of the boat body to improve the heat dissipation efficiency and keep the temperature of the graphite boat stable, the outer boat pages 1 and the inner boat pages 2 are jointly inserted with first ceramic rods 6 in a linear array, and the first ceramic rods 6 are installed in a linear array along the long edge direction of the inner boat pages 2, the design of micropores and heat dissipation channels improves the heat conduction efficiency and reduces heat accumulation, and the overall structure of the graphite boat is simple and easy to manufacture and maintain;

[0038] Graphite pads are used to keep the outer ship leaf 1 and the inner ship leaf 2 apart. The graphite pads include a pair of front pads installed at the furnace mouth and a rear pad installed at the furnace tail. The front pads and the rear pads have the same structure. The front pads include a first pad group 3 and a second pad group 4. The first pad group 3 is installed above the second pad group 4 through the boat body. The outer ship leaf 1 is installed in parallel and alternately with the inner ship leaf 2 through the first pad group 3 and the second pad group 4.

[0039] A temperature equalization system is used to heat and control the temperature of the boat body. The temperature equalization system includes a heat conducting mechanism, a thermocouple 12 and a control unit. The heat conducting mechanism includes a heat conducting member 5, a first electric heating wire ring 9 and a second electric heating wire ring 13. The heat conducting member 5 is embedded and installed on the top of the boat body. The heat conducting member 5 is installed on the top between the outer ship leaf 1 and the inner ship leaf 2. The first electric heating wire ring 9 is installed inside the first pad block group 3 and the second pad block group 4. The second electric heating wire ring 13 is installed on the left and right sides of the first electric heating wire ring 9. The first electric heating wire ring 9 is used to heat the graphite pad. The heat conducting mechanism is used to equalize the temperature of various areas in the boat body.

[0040] The thermocouple 12 is inserted into the first pad group 3 in a vertically symmetrical manner, and the second pad group 4 is also equipped with a thermocouple 12. The thermocouple 12 is used to monitor the temperature of the surface of the boat body in real time. The thermocouple 12 transmits the monitored temperature data to the control unit. The control unit is connected to the thermocouple 12 and the heat conducting mechanism, and is used to adjust the heat conducting effect of the heat conducting mechanism according to the monitoring results of the thermocouple 12. That is to say, the thermocouples 12 are evenly arranged on the graphite pads at the furnace mouth and the furnace tail, and the temperature of each area can be monitored in real time.

[0041] The control unit includes a microprocessor and an execution unit. The microprocessor receives data transmitted by the thermocouple 12 and performs calculations. If it is found that the temperature deviation in a certain area is large, the execution unit is controlled to adjust the thermal power effect of the thermal conductive mechanism to achieve a balanced temperature distribution.

[0042] The second ceramic rod 7 and the carbon fiber rod 8 are embedded and installed inside the first pad block group 3. The second ceramic rod 7 is installed side by side on the left side of the carbon fiber rod 8 through the first pad block group 3. The bottom of the second pad block group 4 is symmetrically installed with a support member 10. The outer ship leaf 1 on the boat body is assembled with the inner ship leaf 2 through the first ceramic rod 6, the second ceramic rod 7, the carbon fiber rod 8, the first electric heating wire ring 9, the thermocouple 12 and the second electric heating wire ring 13.

[0043] A heat dissipation channel 21 is opened on the surface of the inner ship leaf 2 near the bottom, and the heat dissipation channel 21 is opened at equal intervals along the long side edges of the inner ship leaf 2. The second pad group 4 is composed of a pressure regulating pad 32 and a square pad 33 through a second ceramic rod 7, a carbon fiber rod 8 and a first electric heating wire ring 9, a thermocouple 12 and a second electric heating wire ring 13.

[0044] The first pad group 3 includes a pair of trapezoidal pads 31, a pair of pressure-regulating pads 32 are installed between the pair of trapezoidal pads 31, and a pair of square pads 33 are installed between the pair of pressure-regulating pads 32, and the pressure-regulating pads 32 are installed between the trapezoidal pads 31 and the square pads 33, and the carbon fiber rod 8 and the second ceramic rod 7 are arranged side by side and pass through the trapezoidal pads 31, the pressure-regulating pads 32 and the square pads 33 in sequence.

[0045] The front and rear surfaces of the terraced pad 31, the pressure-regulating pad 32 and the square pad 33 are all symmetrically provided with vertical cavities 34 for connecting the pad structures to which the graphite pads belong to facilitate heat transfer. The front and rear sides of the top of the support member 10 are fixedly connected with semi-columns 11, and the support member 10 is inserted into the square pad 33 through the semi-columns 11 and the cavities 34. The pressure-regulating pad 32 is provided with pressure-regulating seams in a centrally symmetrical shape, which can adjust the interval between the ship leaf structures of the boat body within a small range, and provide a certain expandable range for the thermal expansion of the ship leaves.

[0046] The square pad 33 includes a pair of external pads 331, a pair of internal pads 332 are installed between the pair of external pads 331, square grooves are opened on the wall surfaces of the external pads 331 and the internal pads 332 in the same direction, and convex tube sleeves 333 are fixedly connected to the corners of the wall surfaces of the external pads 331 and the internal pads 332 in the same direction, and the internal pads 332 are inserted into the external pads 331 through the convex tube sleeves 333, wherein a groove cavity 334 is opened in the middle of the square grooves of the external pads 331 and the internal pads 332.

[0047] When in use, the pad structures belonging to the first pad group 3 and the second pad group 4 are both composed of phase change material blocks 35 and heat conducting plates 36 as well as internal and external pad structures. Therefore, each pad structure is composed of heat conducting material and phase change material as a whole. While being able to guide and transfer the heat energy between the pad structures, it is also possible to utilize the characteristics of the phase change material that absorbs heat when the temperature rises and releases heat when the temperature drops to balance the temperature between the graphite pads, thereby assisting in balancing the temperature of the boat body, thereby establishing a structural control basis for balancing the temperature to ensure the uniformity of the coating thickness and the quality of the coating.

[0048] By using the microporous structure on the surface of the outer ship leaf 1 and the inner ship leaf 2, and utilizing the structural design in which the microporous distribution density gradually increases from the center of the ship leaf to the two ends, the flow of hot air is promoted to achieve a more uniform temperature distribution; and combined with the structural design of the heat dissipation channels 21 opened on the bottom of the surface of the outer ship leaf 1 and the inner ship leaf 2, the bottoms of the ship leaf structures of the boat body are connected to each other, thereby improving the heat dissipation efficiency and maintaining the temperature of the graphite boat stable. With the combined effects of these two structural designs, the graphite boat itself has a basic operating structure that can ensure that its own temperature is balanced, and can provide an excellent structural control basis for the temperature balance system to balance the temperature of the boat body, provide effective constant temperature control conditions, and assist in the temperature balance system to easily control the temperature of the boat body to quickly balance it.

[0049] During the use of the boat, the temperature of the pad structure of the boat near the furnace mouth and the furnace tail is monitored in real time through the thermocouple 12, and the monitored temperature data is transmitted to the control unit through the thermocouple 12. The control unit is connected with the thermocouple 12 and the heat conducting mechanism to adjust the heating power of each structural component of the heat conducting mechanism in real time according to the monitoring result of the thermocouple 12. The output power of the heat conducting element 5, the first electric heating wire ring 9 and the second electric heating wire ring 13 can be adjusted respectively, and the heat conducting effect of the heat conducting mechanism can be changed, so as to realize the automatic adjustment and balancing function of the pad temperature at the furnace mouth and the furnace tail of the boat and realize the balanced distribution of temperature.

[0050] Through the above operation, the graphite boat can solve the problem of uneven temperature field distribution caused by the presence of large graphite composite pad structures at the furnace mouth and furnace tail of the traditional graphite boat during PECVD, eliminate the uneven coating film thickness caused by stress and defects in the silicon wafer during the heat treatment process, and enable the graphite boat to automatically adjust and balance the pad temperatures at the furnace mouth and furnace tail, achieve balanced temperature distribution on the graphite boat, and store and release heat energy by itself, making the temperature distribution more uniform, thereby improving the consistency and quality of silicon wafer coating, thereby improving the performance and yield of semiconductor devices.

[0051] The graphite boat of the present invention effectively solves the problem of uneven temperature distribution in the prior art through the above-mentioned structural design. By optimizing its mechanical structure design, it can maintain uniform temperature distribution in a high temperature environment, thereby improving the quality and efficiency of silicon wafer processing. By improving the structural design and material selection of the graphite pad, the temperature distribution is improved and the uniformity of the coating thickness is ensured.

[0052] The graphite boat achieves a balanced distribution of temperature inside and outside the boat through the optimized design of the heat conduction mechanism and the use of thermocouples as temperature sensors, thereby reducing the stress and defects of silicon wafers during heat treatment and improving product quality and yield. Phase change materials can absorb or release a large amount of heat when the temperature changes, thereby further balancing the temperature distribution inside the boat.

[0053] In summary, it can be seen that the graphite boat of the present invention can not only achieve balanced temperature distribution through the heat conduction mechanism, but also further balance the temperature through the phase change characteristics of the phase change material, thereby effectively improving the quality and efficiency of silicon wafer processing.

[0054] The second embodiment is based on the first embodiment. Figures 9 to 11 As shown, a phase change material block 35 and a heat conductive sheet 36 are installed between the external pad 331 and the internal pad 332. The heat absorption and release characteristics of the phase change material are used to balance the temperature distribution. Specifically, the phase change material absorbs heat when the temperature rises and releases heat when the temperature drops, thereby balancing the temperature of each area, and the heat conductive sheet 36 is installed between the phase change material block 35 and the external pad 331. The heat conductive sheet 36 is fixedly connected to the middle of one side of the external pad 331. The three-dimensional sheet 37 is embedded and installed with the external pad 331 through a groove cavity 334 opened in the square groove. The phase change material block 35 and the heat conductive sheet 36 are attached and embedded together in the square groove of the external pad 331. Among them, by designing a heat conductive sheet 36 inside the graphite pad, the heat of each area is evenly conducted to assist the phase change material in achieving temperature balance.

[0055] When in use, the contact area between the heat conductive sheet 36 and the external pad 331 and the internal pad 332 is increased by the three-dimensional sheet 37, which can expand the balanced distribution area of ​​heat inside the pad structure and avoid dead corners of heat transfer. At the same time, the heat transfer efficiency between the pad structures is improved, and the heat regulation efficiency inside the graphite pad is accelerated. No matter whether the pad structure is installed at the furnace mouth or the furnace tail, it can achieve balanced distribution of the temperature of the pad structure at the furnace mouth and the furnace tail with the assistance of the phase change material block 35 and the guidance of the heat diffusion transfer by the three-dimensional sheet 37, thereby eliminating the problem of uneven temperature field distribution of the boat body at the furnace mouth and the furnace tail.

[0056] Through the design of the phase change material block 35, the phase change material is embedded in the graphite pad, and the heat conductive sheet 36 is combined with the phase change material to be assembled into a complete pad structure, so that the terraced pad 31, the voltage regulating pad 32 and the square pad 33 contained in each graphite pad are all composed of high thermal conductivity material and phase change material. At the same time, the heat conductive plate 53 made of high thermal conductivity material and the phase change material are assembled and used, and the heat conductive liquid is filled in the heat conductive pipe 51. When the temperature of a certain area of ​​the boat body rises, the phase change material absorbs heat and undergoes phase change, thereby reducing the temperature of the area; when the temperature drops, the phase change material releases heat, increases the temperature of the area, thereby further balancing the temperature inside the boat body.

[0057] The third embodiment is based on the first and second embodiments. Fig.14 As shown, the heat conducting member 5 includes a heat conducting pipe 51, which is installed at the top between the outer ship leaf 1 and the inner ship leaf 2, and the heat conducting liquid is contained in the heat conducting pipe 51 to enhance the heat conducting effect. An aluminum hoop 52 is fixedly installed on the surface of the heat conducting pipe 51 and close to the boat body. The aluminum hoop 52 is clamped with the first ceramic rod 6. A heat conducting plate 53 is fixedly connected to the surface of the heat conducting pipe 51 and close to the boat body. The heat conducting plate 53 is installed between two adjacent aluminum hoop 52, and the heat conducting plates 53 are evenly distributed between the outer ship leaf 1 and the inner ship leaf 2. The heat conducting plates 53 are made of high thermal conductivity material, and phase change material is embedded and installed on the surface of the heat conducting plates 53. The heat conducting pipe 51 connects the heat conducting plates 53 together to form a complete heat conducting network.

[0058] When in use, the heat pipe 51 installed on the top between the outer ship page 1 and the inner ship page 2 is used to control the temperature between the outer ship page 1 and the inner ship page 2, and the heat transfer liquid is contained in the heat pipe 51 to enhance the heat transfer effect of the heat pipe 51. At the same time, the heat transfer plate 53 is effectively used to dissipate the heat balance part between the outer ship page 1 and the inner ship page 2, and the heat transfer plate 53 is connected together by the heat pipe 51 to form a complete heat transfer network, so that the heat conductive element 5 can automatically balance the temperature of the top of the graphite boat while being regulated by the control unit.

[0059] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A graphite boat with uniform temperature distribution, characterized in that: include: A boat body, used for carrying silicon wafers, the boat body is composed of a plurality of outer boat pages (1) and inner boat pages (2) which are installed in parallel and at intervals, the outer boat pages (1) and the inner boat pages (2) having the same structure, the surface of the inner boat pages (2) being provided with micropores, and the distribution density of the micropores gradually increasing from the center of the inner boat pages (2) to both ends, the surface of the inner boat pages (2) being provided with heat dissipation channels (21) penetrating through and near the bottom, and the heat dissipation channels (21) being provided at equal intervals along the long side edges of the inner boat pages (2), the heat dissipation channels (21) being communicated with the bottom of the boat body, the outer boat pages (1) and the inner boat pages (2) being provided with first ceramic rods (6) in a linear array, and the first ceramic rods (6) being installed in a linear array along the long side edges of the inner boat pages (2); A graphite pad is used to maintain a spacing between an outer ship leaf (1) and an inner ship leaf (2), the graphite pad comprising a pair of front pads installed at the furnace mouth and a rear pad installed at the furnace tail, the front pad and the rear pad having the same structure, the front pad comprising a first pad group (3) and a second pad group (4), and the first pad group (3) is installed above the second pad group (4) through the boat body, and the outer ship leaf (1) is installed in parallel and alternately with the inner ship leaf (2) through the cooperation of the first pad group (3) and the second pad group (4); A temperature balancing system for heating and controlling the temperature of a boat body, the temperature balancing system comprising a heat conducting mechanism, a thermocouple (12) and a control unit, the heat conducting mechanism comprising a heat conducting element (5), a first electric heating wire ring (9) and a second electric heating wire ring (13), the heat conducting element (5) being mounted on the top of the boat body, the heat conducting element (5) being mounted on the top between an outer boat leaf (1) and an inner boat leaf (2), the first pad block group (3) and the second pad block group (4) both being mounted with the first electric heating wire ring (9), the second electric heating wire ring (13) being mounted on the left and right sides of the first electric heating wire ring (9), the first electric heating wire ring (9) being used to heat the graphite pad block; The thermocouple (12) is inserted into the first cushion block group (3) in a vertically symmetrical manner, and the second cushion block group (4) is also equipped with a thermocouple (12). The thermocouple (12) is used to monitor the temperature of the surface of the boat body in real time. The thermocouple (12) transmits the monitored temperature data to the control unit. The control unit is connected to the thermocouple (12) and the heat conduction mechanism and is used to adjust the heat conduction effect of the heat conduction mechanism according to the monitoring result of the thermocouple (12). The control unit comprises a microprocessor and an execution unit, wherein the microprocessor receives data transmitted by the thermocouple (12) and controls the execution unit to adjust the heat conduction power of the heat conduction mechanism; A second ceramic rod (7) and a carbon fiber rod (8) are embedded and installed inside the first cushion block group (3); the second ceramic rod (7) is installed side by side on the left side of the carbon fiber rod (8) through the first cushion block group (3); and a support member (10) is installed at the bottom of the second cushion block group (4) in a front-to-back symmetrical manner; The outer boat leaf (1) on the boat body is assembled with the inner boat leaf (2) by means of a first ceramic rod (6), a second ceramic rod (7), a carbon fiber rod (8), a first electric heating wire ring (9), a thermocouple (12) and a second electric heating wire ring (13); the second pad block group (4) is composed of a pressure regulating pad block (32) and a square pad block (33) by means of a second ceramic rod (7), a carbon fiber rod (8), a first electric heating wire ring (9), a thermocouple (12) and a second electric heating wire ring (13).

2. The graphite boat with uniform temperature distribution according to claim 1, characterized in that: The first pad group (3) comprises a pair of terraced pads (31), a pair of pressure-regulating pads (32) are installed between the pair of terraced pads (31), and a pair of square pads (33) are installed between the pair of pressure-regulating pads (32), and the pressure-regulating pads (32) are installed between the terraced pads (31) and the square pads (33), and the carbon fiber rod (8) and the second ceramic rod (7) are arranged side by side and pass through the terraced pads (31), the pressure-regulating pads (32) and the square pads (33) in sequence.

3. The graphite boat with uniform temperature distribution according to claim 2, characterized in that: The front and rear surfaces of the terraced pad (31), the pressure regulating pad (32) and the square pad (33) are vertically provided with cavities (34) in a left-right symmetrical manner, which are used to connect the pad structures to which the graphite pad belongs. The front and rear sides of the top of the support member (10) are fixedly connected with semi-pillars (11). The support member (10) is inserted into the square pad (33) through the cooperation of the semi-pillars (11) and the cavities (34). The pressure regulating pad (32) is provided with a pressure regulating seam in a centrally symmetrical manner.

4. The graphite boat with uniform temperature distribution according to claim 3, characterized in that: The square pad (33) comprises a pair of external pads (331), a pair of internal pads (332) being installed between the pair of external pads (331), square grooves being provided on the wall surfaces of the external pads (331) and the internal pads (332) in the same direction, and convex tube sleeves (333) being fixedly connected to the corners of the wall surfaces of the external pads (331) and the internal pads (332) in the same direction, the internal pads (332) being inserted into the external pads (331) via the convex tube sleeves (333), wherein a groove cavity (334) is provided in the middle of the square grooves of the external pads (331) and the internal pads (332).

5. The graphite boat with uniform temperature distribution according to claim 4, characterized in that: A phase change material block (35) and a heat conducting sheet (36) are installed between the external pad (331) and the internal pad (332), and the heat conducting sheet (36) is installed between the phase change material block (35) and the external pad (331), a three-dimensional sheet (37) is fixedly connected to the middle of a surface of the heat conducting sheet (36) facing the external pad (331), the three-dimensional sheet (37) is mounted in an inlaid manner with the external pad (331) via a groove cavity (334) opened in the square groove, and the phase change material block (35) and the heat conducting sheet (36) are attached to and jointly inlaid in the square groove of the external pad (331).

6. The graphite boat with uniform temperature distribution according to claim 5, characterized in that: The heat conducting member (5) comprises a heat conducting pipe (51), the heat conducting pipe (51) being installed at the top between the outer ship leaf (1) and the inner ship leaf (2), and the heat conducting fluid being contained in the heat conducting pipe (51), an aluminum hoop sleeve (52) being fixedly installed on the surface of the heat conducting pipe (51) and close to the boat body, the aluminum hoop sleeve (52) being clamped with the first ceramic rod (6), a heat conducting plate (53) being fixedly connected on the surface of the heat conducting pipe (51) and close to the boat body, the heat conducting plate (53) being installed between two adjacent aluminum hoop sleeves (52), and the heat conducting plates (53) being evenly distributed between the outer ship leaf (1) and the inner ship leaf (2), the heat conducting plates (53) being made of a high thermal conductivity material, and a phase change material being embedded and installed on the surface of the heat conducting plates (53).

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