Photovoltaic silicon wafer light annealing equipment

Abstract

The utility model discloses photovoltaic silicon wafer light annealing equipment which comprises a transmission device, a preheating and drying device, an annealing device and a cooling device which are sequentially arranged and are respectively provided with a transmission channel. And the transmission devices are arranged in the plurality of transmission channels and are used for bearing and transferring the photovoltaic silicon wafers. And the transmission device is a chain type transmission device, is provided with a transmission rod connected with the chain and a transmission carrier arranged on the transmission rod, and is used for bearing the photovoltaic silicon wafer. The preheating and drying device comprises a protective gas filling assembly which is used for filling protective gas into the preheating and drying device so as to protect the photovoltaic silicon wafer. And the preheating and drying device is used for heating the photovoltaic cell to be subjected to light annealing, so that the photovoltaic cell enters an annealing area to maintain the optimal temperature of light annealing and maintain the temperature stability of a photovoltaic silicon wafer in the annealing area, and the photovoltaic silicon wafer is at the optimal temperature and is subjected to light annealing to ensure that a good passivation film is formed on the surface of the photovoltaic silicon wafer.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cell production, in particular to photovoltaic silicon slice light annealing equipment. Background Art

[0002] In the photovoltaic silicon wafer curing process, light annealing is a key step to produce a good passivation protective layer on the surface of the photovoltaic silicon wafer. Among them, how to keep the photovoltaic silicon wafer at an optimal temperature level in the light source module is a technical difficulty. In existing equipment, there is no good measure to maintain the temperature stability of the photovoltaic silicon wafer in the annealing zone. Utility Model Content

[0003] In order to overcome the above shortcomings, the purpose of the present invention is to provide a photovoltaic silicon wafer optical annealing device to solve the problem of difficulty in maintaining the temperature stability of the photovoltaic silicon wafer in the annealing zone mentioned in the above background technology.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is a photovoltaic silicon wafer light annealing device, including a transmission device, a preheating and drying device, an annealing device and a cooling device, wherein:

[0005] The preheating and drying device, the annealing device and the cooling device are arranged in sequence along a first direction, and are all provided with a transmission channel extending along the first direction.

[0006] The transmission device is laid in the plurality of transmission channels along the first direction, and is used to carry and transport photovoltaic silicon wafers. The transmission device is a chain transmission device, which has a transmission rod connected to a chain and a transmission carrier arranged on the transmission rod, and is used to carry the photovoltaic silicon wafers.

[0007] The preheating and drying device includes a protective gas filling component, which fills the preheating and drying device with protective gas to protect the photovoltaic silicon wafer. The temperature of the preheating and drying device can be adjusted to 400°C at most, which is used to heat the photovoltaic silicon wafer. The annealing device is used to perform photoannealing treatment on the photovoltaic silicon wafer. The cooling device is used to cool the photovoltaic silicon wafer.

[0008] The photovoltaic silicon wafer photoannealing equipment provided by the utility model is arranged along the conveying direction of the photovoltaic cell as a whole. The transmission device drives the photovoltaic silicon wafer to move along the first direction and passes through multiple transmission channels in sequence, so that the photovoltaic silicon wafer can enter from the preheating and drying device and leave from the cooling device. The preheating and drying device is used to heat the photovoltaic cell to be photoannealed, so that it can maintain the optimal temperature of photoannealing when entering the annealing zone, maintain the temperature stability of the photovoltaic silicon wafer in the annealing zone, so that the photovoltaic silicon wafer is at the optimal temperature and photoannealing is performed to ensure that a good passivation film is formed on the surface of the photovoltaic silicon wafer. The protective gas filling component is used to fill the preheating and drying device with protective gas, and the protective gas is used to protect the surface of the photovoltaic cell from oxidation. The photoannealing device is used to passivate the photovoltaic cell and improve its electrical performance. The cooling device is used to quickly cool the photovoltaic silicon wafer.

[0009] In some embodiments, the preheating and drying device is provided with a plurality of heat exhaust outlets, a waste exhaust pipe and a heat exhaust fan at the top along the second direction, and the second direction is perpendicular to the first direction. The waste exhaust pipe is connected to the plurality of heat exhaust outlets respectively. The heat exhaust fan is connected to the waste exhaust pipe for centrally exhausting the heat in the furnace body.

[0010] By adopting the above technical solution, a heat exhaust port is set to discharge the heat in the furnace body. Multiple heat exhaust ports are gathered in the waste exhaust main pipe, and the heat is guided from the waste exhaust main pipe flow by the heat exhaust fan to prevent excessive accumulation of heat in the preheating and drying device, causing unstable temperature increase and affecting the stability of the device.

[0011] In some embodiments, the protective gas charging assembly includes a plurality of protective gas inlets. The plurality of protective gas inlets are arranged on both sides of the preheating and drying device along the third direction, and the first direction, the second direction and the third direction are perpendicular to each other. The plurality of protective gas inlets are arranged at intervals along the first direction, and are used to charge the protective gas into the preheating and drying device through the plurality of protective gas inlets to protect the photovoltaic silicon wafer.

[0012] By adopting the above technical solution, the preheating and drying device is connected to the external protective gas filling device through multiple protective gas inlets, so as to fill the protective gas into the preheating and drying device to protect the photovoltaic silicon wafers located in the transmission channel.

[0013] In some embodiments, the annealing device includes a light source module and a cooling module. The light source module and the cooling module are both arranged above the transmission channel. The light source module includes a plurality of light injection units for emitting light beams to the photovoltaic silicon wafer to passivate its surface. The cooling module includes a cold water tank and an air knife device, the cold water tank is used to cool the light source module, and the air knife device is used to cool the photovoltaic silicon wafer.

[0014] With the above technical solution, the light source module is used to provide illumination. The light source module includes a plurality of independently controllable light injection units. The light-emitting front of the light injection unit is arranged toward the photovoltaic cell. The light-emitting front of the plurality of light injection units is arranged along the transmission direction of the transmission device. By arranging a cold water tank, the heat on the light-emitting back side of the light injection unit can be dissipated through heat exchange with cold water. Cooling water inlets and outlets are arranged at both ends of the cold water tank. Two independently arranged cooling water circuits are arranged inside for cooling. When one cooling water circuit fails, cooling can also be performed through another cooling water circuit to improve the cooling effect. The exhaust port of the wind knife device is arranged toward the photovoltaic cell, and the blowing rod of the wind knife device is connected to the air source device. The exhaust of the wind knife device is continuous, so that the cooling gas covering the surface of the photovoltaic silicon wafer is also continuous, and the cooling of the photovoltaic silicon wafer is more uniform.

[0015] In some embodiments, the annealing device further comprises a heat exchanger. The heat exchanger is disposed below the transmission channel and is used to cool the cavity of the annealing device.

[0016] In some embodiments, the wind knife device includes a large-displacement wind knife and a small-displacement wind knife, and the large-displacement wind knife and the small-displacement wind knife are alternately arranged on the top of the light source module along the third direction.

[0017] In some embodiments, the plurality of light injection units irradiate vertically along a transmission direction of the photovoltaic silicon wafer.

[0018] In some embodiments, the plurality of light injection units can also perform curved surface concentrated irradiation along the transmission direction of the photovoltaic silicon wafer.

[0019] In some embodiments, the wavelength band of each light injection unit is: white light 400nm-700nm or red light 613nm-660nm.

[0020] In some embodiments, the cooling device adopts at least one cooling method of air cooling or water cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a three-dimensional diagram of an embodiment of a photovoltaic silicon wafer optical annealing device of the utility model;

[0022] Figure 2 This is a partial structural schematic diagram of an embodiment of a photovoltaic silicon wafer optical annealing device of the utility model;

[0023] In the figure:

[0024] 1-Photovoltaic silicon wafer light annealing equipment; 2-Transmission device; 3-Preheating and drying device; 30-Heat exhaust outlet; 31-Waste exhaust main pipe; 32-Protective gas inlet; 4-Annealing device; 40-Light injection unit; 41-Cooling water inlet and outlet; 42-Wind knife device; 43-Blowing rod; 5-Cooling device; 50-Air cooling device; 6-Reserved section. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0026] refer to Figure 1 and Figure 2 , Figure 1 A three-dimensional diagram of a photovoltaic silicon wafer optical annealing device provided by an embodiment of the utility model is shown; Figure 2 A partial structural schematic diagram of a photovoltaic silicon wafer photoannealing device provided in an embodiment of the utility model is shown.

[0027] like Figure 1 and Figure 2 As shown, the figure shows a photovoltaic silicon wafer optical annealing device 1 provided by the utility model, including a transmission device 2, a preheating and drying device 3, an annealing device 4 and a cooling device 5, wherein:

[0028] The preheating and drying device 3, the annealing device 4 and the cooling device 5 are arranged along the first direction ( Figure 1 The transmission devices 2 are arranged in sequence along the first direction (shown in the X direction) and are all provided with a transmission channel extending along the first direction. The transmission device 2 is laid in the plurality of transmission channels along the first direction, and is used to carry and transport the photovoltaic silicon wafers. The transmission device 2 is a chain transmission device 2, which has a transmission rod connected to the chain and a transmission carrier arranged on the transmission rod, and is used to carry the photovoltaic silicon wafers.

[0029] The preheating and drying device 3 includes a protective gas filling component, which fills the preheating and drying device 3 with protective gas to protect the photovoltaic silicon wafer. The temperature of the preheating and drying device 3 can be adjusted to 400°C at most, which is used to heat the photovoltaic silicon wafer. The annealing device 4 is used to perform photoannealing treatment on the photovoltaic silicon wafer. The cooling device 5 is used to cool the photovoltaic silicon wafer.

[0030] The photovoltaic silicon wafer light annealing device 1 provided in the present application is arranged along the conveying direction of the photovoltaic cell as a whole, and the transmission device 2 drives the photovoltaic silicon wafer to move along the first direction, passing through multiple transmission channels in sequence, so that the photovoltaic silicon wafer can enter from the preheating and drying device 3 and leave from the cooling device 5. The preheating and drying device 3 is used to heat the photovoltaic cell to be light-annealed, so that it can maintain the optimal temperature of light annealing when entering the annealing zone, maintain the temperature stability of the photovoltaic silicon wafer in the annealing zone, so that the photovoltaic silicon wafer is at the optimal temperature and light annealing is performed to ensure that a good passivation film is formed on the surface of the photovoltaic silicon wafer. The protective gas filling component is used to fill the protective gas into the preheating and drying device 3, and the protective gas protection is used to prevent the surface of the photovoltaic cell from being oxidized. The light annealing device 4 is used to passivate the photovoltaic cell and improve its electrical performance. The cooling device 5 is used to quickly cool the photovoltaic silicon wafer. The protective gas in this embodiment is nitrogen, but the present application does not limit the type of protective gas, and a single gas that does not chemically react with the slurry or silicon wafer can also be used, such as oxygen, helium, neon, etc.

[0031] In some embodiments, reference Figure 1 and Figure 2 , the preheating and drying device 3 is arranged along the second direction ( Figure 1 A plurality of heat exhaust ports 30, a waste exhaust pipe 31 and a heat exhaust fan are provided on the top of the furnace body (shown in the Z direction), and the second direction is perpendicular to the first direction. The waste exhaust pipe 31 is connected to the plurality of heat exhaust ports 30 respectively. The heat exhaust fan is connected to the waste exhaust pipe 31 to centrally exhaust the heat in the furnace body.

[0032] Exemplarily, a heat outlet 30 is provided to discharge the heat in the furnace body, and a plurality of heat outlets 30 are gathered in the exhaust main pipe 31, and the heat is guided to flow from the exhaust main pipe 31 by the heat exhaust fan, so as to prevent excessive accumulation of heat in the preheating and drying device 3, causing unstable temperature rise and affecting the stability of the device. The heating element used for heating in the preheating and drying device 3 can be selected from at least one of an electromagnetic heating element, an infrared heating element, an ultraviolet heating element, and an LED heating element. For example, an infrared lamp is selected as the infrared heating element, and the infrared lamp is respectively arranged on the upper and lower sides of the transmission channel, that is, the lower surface of the upper cover plate of the upper heating cavity and the upper surface of the lower cover plate of the lower heating cavity.

[0033] In some embodiments, reference Figure 1 and Figure 2 The protective gas charging assembly includes a plurality of protective gas inlets 32. The plurality of protective gas inlets 32 are arranged along the third direction ( Figure 1The first direction, the second direction and the third direction are perpendicular to each other. A plurality of protective gas inlets 32 are arranged at intervals along the first direction, and are used to fill the preheating and drying device 3 with protective gas through the plurality of protective gas inlets 32 to protect the photovoltaic silicon wafer.

[0034] Exemplarily, the preheating and drying device 3 is connected to an external protective gas filling device through a plurality of protective gas inlets 32 so as to fill the preheating and drying device 3 with protective gas to protect the photovoltaic silicon wafers in the transmission channel.

[0035] In some embodiments, reference Figure 1 and Figure 2 The annealing device 4 includes a light source module and a cooling module. Both the light source module and the cooling module are arranged above the transmission channel. The light source module includes a plurality of light injection units 40, which are used to emit light beams to the photovoltaic silicon wafer to passivate its surface. The cooling module includes a cold water tank and an air knife device 42, the cold water tank is used to cool the light source module, and the air knife device 42 is used to cool the photovoltaic silicon wafer.

[0036] Exemplarily, the light source module is used to provide illumination, and the light source module includes a plurality of independently controllable light injection units 40, the light-emitting front of the light injection unit 40 is arranged toward the photovoltaic cell, and the light-emitting front of the plurality of light injection units 40 is arranged along the transmission direction of the transmission device 2. By setting a cold water tank, the heat on the light-emitting back side of the light injection unit 40 can be dissipated through heat exchange with cold water to achieve a heat dissipation effect. Both ends of the cold water tank are provided with cooling water inlet and outlet 41, and two independently arranged cooling water circuits are arranged inside for cooling. When one cooling water circuit fails, cooling can also be performed through another cooling water circuit to improve the cooling effect. The exhaust port of the wind knife device 42 is arranged toward the photovoltaic cell, and the blowing rod 43 of the wind knife device 42 is connected to the air source device. The exhaust of the wind knife device 42 is continuous, so that the cooling gas covering the surface of the photovoltaic silicon wafer is also continuous, and the cooling of the photovoltaic silicon wafer is more uniform.

[0037] Specifically, the plurality of light injection units 40 irradiate vertically along the transmission direction of the photovoltaic silicon wafer. In some embodiments, the plurality of light injection units 40 can also perform curved concentrated irradiation along the transmission direction of the photovoltaic silicon wafer.

[0038] In some embodiments, the annealing device 4 further includes a heat exchanger. The heat exchanger is disposed below the transmission channel and is used to cool the cavity of the annealing device 4.

[0039] In some embodiments, the wind knife device 42 includes a large-displacement wind knife and a small-displacement wind knife, and the large-displacement wind knife and the small-displacement wind knife are alternately arranged on the top of the light source module along the third direction.

[0040] In some embodiments, the wavelength band of each light injection unit 40 is: 400nm-700nm for white light or 613nm-660nm for red light.

[0041] In some embodiments, the cooling device 5 uses at least one cooling method of air cooling or water cooling.

[0042] Exemplarily, the cooling device 5 in the present application is an air cooling device 50 .

[0043] In some embodiments, reference Figure 1 A reserved section 6 is also provided between the annealing device 4 and the cooling device 5 .

[0044] Exemplarily, the reserved section 6 is used to appropriately extend or shorten the annealing device 4 according to actual production requirements, that is, the light annealing time of the photovoltaic silicon wafer.

[0045] The above implementation modes are only for illustrating the technical concept and features of the utility model, and their purpose is to allow people familiar with this technology to understand the content of the utility model and implement it. It cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A photovoltaic silicon wafer optical annealing device, characterized in that: It includes a transmission device, a preheating and drying device, an annealing device and a cooling device, wherein: The preheating and drying device, the annealing device and the cooling device are sequentially arranged along a first direction, and are all provided with a transmission channel extending along the first direction; The transmission device is laid in the plurality of transmission channels along the first direction, and is used to carry and transport the photovoltaic silicon wafers; the transmission device is a chain transmission device, which has a transmission rod connected to the chain and a transmission carrier arranged on the transmission rod, and is used to carry the photovoltaic silicon wafers; The preheating and drying device includes a protective gas filling component, which fills the preheating and drying device with protective gas to protect the photovoltaic silicon wafer; the temperature of the preheating and drying device can be adjusted to a maximum of 400°C, which is used to heat the photovoltaic silicon wafer; the annealing device is used to perform photoannealing treatment on the photovoltaic silicon wafer; and the cooling device is used to cool the photovoltaic silicon wafer.

2. The photovoltaic silicon wafer optical annealing equipment according to claim 1, characterized in that: The preheating and drying device is provided with a plurality of heat exhaust outlets, a waste exhaust pipe and a heat exhaust fan at the top along the second direction, and the second direction is perpendicular to the first direction; the waste exhaust pipe is connected to the plurality of heat exhaust outlets respectively; the heat exhaust fan is connected to the waste exhaust pipe for centrally discharging the heat in the furnace body.

3. The photovoltaic silicon wafer optical annealing equipment according to claim 2, characterized in that: The protective gas filling component includes multiple protective gas inlets; the multiple protective gas inlets are arranged on both sides of the preheating and drying device along the third direction, and the first direction, the second direction and the third direction are perpendicular to each other; the multiple protective gas inlets are arranged at intervals along the first direction, and are used to fill the preheating and drying device with protective gas through the multiple protective gas inlets to protect the photovoltaic silicon wafers.

4. The photovoltaic silicon wafer optical annealing equipment according to claim 3, characterized in that: The annealing device includes a light source module and a cooling module; the light source module and the cooling module are both arranged above the transmission channel; the light source module includes a plurality of light injection units for emitting light beams to the photovoltaic silicon wafer to passivate its surface; the cooling module includes a cold water trough and a wind knife device, the cold water trough is used to cool the light source module, and the wind knife device is used to cool the photovoltaic silicon wafer.

5. The photovoltaic silicon wafer optical annealing equipment according to claim 4, characterized in that: The annealing device further comprises a heat exchanger; the heat exchanger is arranged below the transmission channel and is used to cool the cavity of the annealing device.

6. The photovoltaic silicon wafer optical annealing equipment according to claim 4, characterized in that: The wind knife device comprises a large-displacement wind knife and a small-displacement wind knife, and the large-displacement wind knife and the small-displacement wind knife are alternately arranged on the top of the light source module along the third direction.

7. The photovoltaic silicon wafer optical annealing equipment according to claim 4, characterized in that: The plurality of light injection units irradiate vertically along a transmission direction of the photovoltaic silicon wafer.

8. The photovoltaic silicon wafer optical annealing equipment according to claim 4, characterized in that: The multiple light injection units can also perform curved surface concentrated irradiation along the transmission direction of the photovoltaic silicon wafer.

9. The photovoltaic silicon wafer optical annealing equipment according to claim 4, characterized in that: The wavelength band of each light injection unit is: white light 400nm-700nm or red light 613nm-660nm.

10. The photovoltaic silicon wafer optical annealing equipment according to claim 1, characterized in that: The cooling device adopts at least one cooling method of air cooling or water cooling.

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