Film coating furnace tube structure and process of back-texturing type back contact battery

Abstract

The invention discloses a coating furnace tube structure and process of a post-texturing type back contact battery. Relates to the technical field of back contact batteries. The special gas pipeline component comprises a first special gas pipeline, a second special gas pipeline and a third special gas pipeline, the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are arranged on the inner wall of the furnace tube body at intervals, and the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are circumferentially and uniformly distributed; a plurality of vent holes are formed in the first special gas pipeline, the second special gas pipeline and the third special gas pipeline; and the auxiliary heating components are arranged on the side, away from the special gas pipeline component, of the inner wall of the furnace tube body, and the three auxiliary heating components are sequentially arranged in the axis direction of the furnace tube body at intervals. By arranging the special gas pipeline component, the gas inlet distribution is improved, and the deposition difference between the furnace mouth and the furnace tail is reduced; three sections of auxiliary heating components are arranged for independent control, the temperature difference of a furnace tube body temperature area is reduced, and the set temperature difference in the process is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of back contact batteries, and more particularly to a coating furnace tube structure and process for a post-texture-made back contact battery. Background Art

[0002] BC cell refers to the back contact cell, an advanced design cell used to improve the efficiency of solar cells. However, due to the basic structural framework of the technical route of the cell, the absence of grid lines on the front makes its light absorption area larger, the light conversion is better, and the uniformity of the front film layer is more stringent. The conventional furnace mouth air intake and Y-line air intake pipeline method, because its air intake method is from the furnace mouth to the furnace tail, the flow deposition at the furnace mouth position is large, resulting in a higher refractive index at the furnace mouth than at the furnace tail, and there is a difference between the mouth and the tail of the whole tube. This design uses a segmented gas pipeline, an air intake method at the mouth and tail, and the corresponding angle of the pipeline to make the intake gas counter-mixed, which can effectively improve the distribution of special gases in the tube and improve the deposition difference at the mouth and tail. Because the conventional furnace tube auxiliary heating tube is an integrated heating method, the tail current is passed through the heating wire and heating rod to assist in heating. The temperature difference between the mouth and the tail of the temperature zone is large, and the difference is 50-120℃, which greatly affects the consistency of the battery after coating and has the risk of subsequent color difference and efficiency difference.

[0003] Therefore, how to provide a coating furnace tube structure and process for a post-textured back-contact battery that reduces the temperature difference between furnace tube temperature zones and improves air intake distribution is an issue that technical personnel in this field urgently need to solve. Summary of the invention

[0004] In view of this, the present invention provides a coating furnace tube structure and process for a post-textured back-contact battery, aiming to solve one of the problems in the above-mentioned background technology, reduce the temperature difference in the furnace tube temperature zone, and improve the air intake distribution.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A coating furnace tube structure for a post-texturing back contact battery, comprising:

[0007] Furnace tube body;

[0008] The special gas pipeline component comprises a first special gas pipeline, a second special gas pipeline and a third special gas pipeline, wherein the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are arranged at intervals on the inner wall of the furnace tube body, the first special gas pipeline, the second special gas pipeline and the third special gas pipeline all pass through the head and tail of the furnace tube body, the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are evenly distributed around the circumference, and the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are all provided with a plurality of vents;

[0009] The auxiliary heating component is arranged on a side of the inner wall of the furnace tube body away from the special gas pipeline component, and three auxiliary heating components are arranged in sequence and spaced apart along the axial direction of the furnace tube body.

[0010] Furthermore, the distance between each two of the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is in the range of 15-20 cm.

[0011] Furthermore, the distance between two adjacent vents on the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is 3-5 cm, and the number of vents on the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is 30-100.

[0012] Furthermore, the shape of the vent hole is set to be a circle, a rectangle or a triangle.

[0013] Furthermore, the furnace tube body adopts a quartz tube wall.

[0014] On the other hand, the present application discloses a coating furnace tube process for a post-textured back contact battery, based on the coating furnace tube structure of a post-textured back contact battery described above, specifically comprising the following steps:

[0015] Step 1: The first special gas pipeline, the second special gas pipeline and the third special gas pipeline are arranged at intervals on the inner wall of the furnace tube body, and an auxiliary heating component is placed on the other side of the furnace tube body, and three auxiliary heating components are placed in sequence from the bottom of the furnace tube body;

[0016] Step 2: Deposit a 4nm AlxOy layer on the front side of the semi-finished battery and a 4nm AlxOy layer on the back side. The aluminum source is trimethylaluminum and the oxygen source is ozone. After completion, place it in the PECVD equipment.

[0017] Step 3: deposit a 75nm thick silicon nitride passivation anti-reflection film with a refractive index of 2.1% on the front side, and deposit a 90nm thick silicon oxide passivation anti-reflection film with a refractive index of 2.10% on the back side;

[0018] Step 4: After the back film is deposited, it is transferred to printing, and finally the aluminum paste is printed on the P area to form a positive electrode through the metallization process, and the silver paste is printed on the N area to form a negative electrode.

[0019] Furthermore, in step three, the front deposition temperature is 500° C., and then the temperature is raised to 650° C. for annealing, and the back deposition temperature is 500° C., and then the temperature is raised to 650° C. for annealing.

[0020] It can be known from the above technical scheme that compared with the prior art, the present invention discloses a coating furnace tube structure and process for a post-velvet back-contact battery, which provides a special gas pipeline component to pass through, split the special gas port and tail area to intake air simultaneously, the furnace tube has its own fixed hook point, and the corresponding number of vents are reserved on the first special gas pipeline, the second special gas pipeline and the third special gas pipeline to make the air inlet tail more uniform, and the air intake method can adopt furnace mouth intake or furnace tail and furnace mouth simultaneous air intake method, and the ventilation angle is hedged in a mixed method, the pipeline passes through the mouth and tail of the furnace tube body, improves the air intake distribution, and reduces the deposition difference between the furnace mouth and the furnace tail; by setting an auxiliary heating component, the three sections of auxiliary heating components are controlled separately, the temperature difference of the furnace tube temperature zone is reduced, and the setting temperature difference within the process is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the coating furnace tube structure of a rear-textured back-contact battery provided by the present invention;

[0023] Figure 2 A side view of the coating furnace tube structure of the rear-textured back-contact battery provided by the present invention;

[0024] Figure 3 A front view of the coating furnace tube structure of the rear-textured back-contact battery provided by the present invention;

[0025] Figure 4 This is a schematic diagram of the passivation annealing film layer structure provided by the present invention.

[0026] Among them: 1 is the furnace tube body; 2 is the first special gas pipeline; 3 is the second special gas pipeline; 4 is the third special gas pipeline; 5 is the auxiliary heating component. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-4 The embodiment of the present invention discloses a coating furnace tube structure of a back-textured back contact battery, comprising:

[0029] Furnace tube body 1; the furnace tube body 1 has fixed pipeline points, and the furnace mouth and furnace tail pipelines are separated and intake air at the same time;

[0030] The special gas pipeline component comprises a first special gas pipeline 2, a second special gas pipeline 3 and a third special gas pipeline 4, the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 are arranged at intervals on the inner wall of the furnace tube body 1, the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 all penetrate the head and tail of the furnace tube body 1, the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 are evenly distributed in a circle, and the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 are all provided with a plurality of vents; a split gas path is adopted to make a separate gas path layout for the gas used, and the distribution pipeline adopts a special gas pipeline component convection mixing method to make the gas mixing more sufficient;

[0031] The auxiliary heating component 5 is arranged on the inner wall of the furnace tube body 1 on a side away from the special gas pipeline component. Three auxiliary heating components 5 are arranged in sequence along the axial direction of the furnace tube body 1; the auxiliary heating is assisted in three stages, and the heating mode is controlled independently. The three stages of auxiliary heating are controlled independently, which avoids the temperature imbalance of the temperature zone caused by the integrated auxiliary heating tube. The three stages of auxiliary heating can perfectly solve the temperature difference problem through independent temperature control. By setting the power of different auxiliary heating, the temperature of the entire temperature zone of the furnace tube body 1 can be set to be consistent.

[0032] In this embodiment, the distance between each two of the first special gas pipeline 2 , the second special gas pipeline 3 and the third special gas pipeline 4 is in the range of 15-20 cm.

[0033] In this embodiment, the distance between two adjacent vents on the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 is 3-5 cm, and the number of vents on the first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 is 30-100.

[0034] In this embodiment, the shape of the vent hole is set to be a circle, a rectangle or a triangle.

[0035] In this embodiment, the furnace tube body 1 adopts a quartz tube wall.

[0036] On the other hand, the present application discloses a coating furnace tube process for a post-textured back contact battery, based on the above-mentioned coating furnace tube structure for a post-textured back contact battery, specifically comprising the following steps:

[0037] Step 1: The first special gas pipeline 2, the second special gas pipeline 3 and the third special gas pipeline 4 are arranged at intervals on the inner wall of the furnace tube body 1, and an auxiliary heating component 5 is placed on the other side of the furnace tube body 1, and three auxiliary heating components 5 are placed in sequence from the bottom of the furnace tube body 1;

[0038] Step 2: Deposit 4nm of Al on the front of the semi-finished battery x O y layer, and 4nm Al was deposited on the reverse side. x O y layer, the aluminum source is trimethyl aluminum, the oxygen source is ozone, and after completion, it is placed in the PECVD equipment;

[0039] Step 3: deposit a 75nm thick silicon nitride passivation anti-reflection film with a refractive index of 2.1% on the front side, and deposit a 90nm thick silicon oxide passivation anti-reflection film with a refractive index of 2.10% on the back side;

[0040] Step 4: After the back film is deposited, it is transferred to printing, and finally the aluminum paste is printed on the P area to form a positive electrode through the metallization process, and the silver paste is printed on the N area to form a negative electrode.

[0041] In this embodiment, the front side deposition temperature in step three is 500° C., which is then raised to 650° C. for annealing, and the back side deposition temperature is 500° C., which is then raised to 650° C. for annealing.

[0042] In addition, in this embodiment, the test data is

[0043] Table 1: Passivation test data

[0044]

[0045] In Table 1, LifetimeatSpec.MCD (μs) – minority carrier lifetime value at specified minority carrier concentration;

[0046] Joat250C (A / cm2) – The overall saturation current density of the sample includes the current in the emitter, high and low junctions on the surface, etc., measured under true high injection conditions;

[0047] SunImpliedVoc(V) – This value is the maximum open circuit voltage that the sample can reach in this state;

[0048] ImpliedFF(%) – This value is the fill factor of this sample.

[0049] Table 2: Elliptical stool test data

[0050]

[0051] Table 3: Reflectivity test data

[0052]

[0053] Table 4: Temperature settings for different furnace tube structures

[0054]

[0055] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0056] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A coating furnace tube structure for a back-textured back contact battery, characterized in that: include: Furnace tube body; The special gas pipeline component comprises a first special gas pipeline, a second special gas pipeline and a third special gas pipeline, wherein the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are arranged at intervals on the inner wall of the furnace tube body, the first special gas pipeline, the second special gas pipeline and the third special gas pipeline all pass through the head and tail of the furnace tube body, the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are evenly distributed around the circumference, and the first special gas pipeline, the second special gas pipeline and the third special gas pipeline are all provided with a plurality of vents; The auxiliary heating component is arranged on a side of the inner wall of the furnace tube body away from the special gas pipeline component, and three auxiliary heating components are arranged in sequence and spaced apart along the axial direction of the furnace tube body.

2. The coating furnace tube structure of a back-textured back contact battery according to claim 1, characterized in that: The distance between each two of the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is in the range of 15-20 cm.

3. The coating furnace tube structure of a back-textured back contact battery according to claim 1, characterized in that: The distance between two adjacent vents on the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is 3-5 cm, and the number of vents on the first special gas pipeline, the second special gas pipeline and the third special gas pipeline is 30-100.

4. The coating furnace tube structure of a back-textured back contact battery according to claim 1, characterized in that: The shape of the vent hole is set to be circular, rectangular or triangular.

5. The coating furnace tube structure of a back-textured back contact battery according to claim 1, characterized in that: The furnace tube body adopts quartz tube wall.

6. A coating furnace tube structure process for a back-textured back-contact battery, according to the coating furnace tube structure for a back-textured back-contact battery according to claim 1, characterized in that: The following steps are involved: Step 1: The first special gas pipeline, the second special gas pipeline and the third special gas pipeline are arranged at intervals on the inner wall of the furnace tube body, and an auxiliary heating component is placed on the other side of the furnace tube body, and three auxiliary heating components are placed in sequence from the bottom of the furnace tube body; Step 2: Deposit 4nm of Al on the front of the semi-finished battery x O y layer, and 4nm Al was deposited on the reverse side. x O y layer, the aluminum source is trimethyl aluminum, the oxygen source is ozone, and after completion, it is placed in the PECVD equipment; Step 3: deposit a 75nm thick silicon nitride passivation anti-reflection film with a refractive index of 2.1% on the front side, and deposit a 90nm thick silicon oxide passivation anti-reflection film with a refractive index of 2.10% on the back side; Step 4: After the back film is deposited, it is transferred to printing, and finally the aluminum paste is printed on the P area to form a positive electrode through the metallization process, and the silver paste is printed on the N area to form a negative electrode.

7. The furnace tube coating process for a post-textured back contact battery according to claim 6, characterized in that: In step three, the front deposition temperature is 500°C, which is then raised to 650°C for annealing; the back deposition temperature is 500°C, which is then raised to 650°C for annealing.

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