CN115753751A - A solar cell substrate inspection method and inspection device - Google Patents

Abstract

A solar cell substrate inspection method and an inspection device thereof belong to the field of photovoltaic cells. Use the test solution to uniformly contact the first area of the solar cell substrate. Under the action of the test solution, the metal copper in the first area not covered by the residual glue can chemically react with the test solution, showing the first color with copper metal A different second color. Therefore, it can be judged whether there is residual glue by observing the color of the first area. By observing the color of the first area treated with the test liquid, it is possible to quickly judge whether there is residual glue in the first area, and the test process does not rely on complex and expensive test equipment, and the operation is simple.

Description

A solar cell substrate inspection method and inspection device

technical field

The present application relates to the technical field of photovoltaic cells, in particular, to a method for inspecting solar cell substrates and an inspection device thereof.

Background technique

Currently, one of the cutting-edge solar photovoltaic technologies is the use of copper interconnection technology to replace traditional silver paste printing. The other biggest advantage of copper interconnection technology over traditional silver paste printing technology is that copper interconnection can be thinned. One of the core technologies of line thinning is the graphic transfer technology of wet film photosensitive adhesive. Copper interconnection battery technology uses wet film photosensitive adhesive printing, development, and electroplating to make copper grid lines of battery sheets, replacing traditional silver paste printing technology.

However, after this technology adopts wet film photoresist for development, a certain proportion of residual glue will appear, resulting in unclean development. Different from traditional industries, this photosensitive adhesive is a colorless and transparent organic polymer material, and it cannot be observed when developing residue occurs. Unclear development of residual glue will cause broken gate defects, which brings great troubles to actual production.

Contents of the invention

The purpose of this application is to provide a solar cell substrate inspection method and its inspection device, so as to partially or completely improve the inspection problem of solar cell substrates not being cleanly developed in the related art.

In the first aspect, the embodiment of the present application provides an inspection method for a solar cell substrate, the solar cell substrate includes a copper seed layer and a photosensitive adhesive layer stacked; , forming the first area; the inspection method is used to inspect whether there is transparent residual glue in the first area. Inspection methods include:

Make the test solution cover the first area, and observe the color of the first area; wherein, the test solution contains substances that can react with copper and change the color of copper into a second color; before the test solution covers the first area, the first area It is the first color; judge whether there is residual glue in the first area according to whether the color of the first area changes completely: if the first color remains in the first area, it means that there is residual glue in the first area.

After the solar cell substrate is removed part of the photosensitive adhesive layer, there may be residual adhesive in the formed first region. The adhesive residue remains on the surface of a part of the copper seed layer, so that the part of the copper seed layer cannot be exposed to the first region. Since the residual glue is transparent, even if the first region is covered with the residual glue, the observed color of the first region is still the color of the copper seed layer, that is, the first color. In the above implementation process, the test solution is used to uniformly contact the first region, so that the copper metal not covered by the residual glue can directly contact the test solution and It reacts chemically with the test liquid and presents a second color different from the first color of copper metal. Therefore, it can be judged whether there is residual glue by observing the color of the first area.

That is, after the test liquid treatment, if the first area still retains the first color, it means that the portion retaining the first color has not reacted with the test liquid, which further indicates that the position retaining the first color is covered with residual glue.

With reference to the first aspect, in an optional implementation manner of the present application, the first region is used for electroplating thickening to form electroplated copper grid lines.

In the preparation process of the solar cell substrate, it is necessary to cover a layer of photosensitive adhesive layer on the copper seed layer, and then remove part of the photosensitive adhesive layer to form the first area of exposed copper on the surface of the solar cell substrate, so as to facilitate subsequent exposure. Electroplated copper grid lines are formed on the first area of copper. In the above implementation process, using the inspection solution to inspect the first area used for electroplating to form the electroplated copper grid line can detect whether there is residual glue in the first area in time, thereby reducing the occurrence of grid lines when the electroplated copper grid line is formed in the first area. Chances of a bad line.

In combination with the first aspect, in an optional embodiment of the present application, if all the colors of the first area are the second color, it means that there is no glue residue in the first area; if all the colors of the first area are the first color, it means that the first area It is fully covered with residual glue; if the color of the first area includes the first color and the second color, it means that the first area is partially covered with residual glue.

If there is no adhesive residue in the first area, after the test liquid covers the first area, the test liquid will react with the copper in the first area, so that the copper in the first area will all change to the second color. At this time, the observed colors of the first region are all the second colors.

If the first area is completely covered with a layer of residual glue, the test liquid cannot change the color of the first area to the second color after the test liquid covers the first area. At this time, all the observed colors of the first region are still the first color.

If part of the first area is covered with residual glue, after the test liquid covers the first area, the test liquid can only make the copper at the other part of the first area not covered by the residual glue change into a second color, And the part covered by the residual glue still retains the first color. At this time, the observed color of the first region has both the first color and the second color.

In combination with the first aspect, in an optional embodiment of the present application, the test solution includes a stannous salt and a copper ion complexing agent, and the pH of the test solution is not greater than 1;

Optionally, the copper ion complexing agent is selected from at least one of thiourea and citric acid.

Using the inspection solution to detect whether there is residual glue in the first area can avoid grid breakage during subsequent electroplating of copper to prepare grid lines. And, when the test solution provided by this example that includes stannous salt and copper ion complexing agent, and pH is not greater than 1, is evenly applied to the first area, the stannous ion of the stannous salt in the test solution is strong Under the acidic environment and the action of copper ion complexing agent, it can have a substitution reaction with the copper not covered by the residual glue in the first area, and metal tin is precipitated on the surface of the copper layer in this part, showing the milky white color of metal tin in the second area. color.

By observing whether the color of the first area treated with the test solution provided in this example shows a second color different from the first color, it is judged whether there is any adhesive residue in the first area.

With reference to the first aspect, in an optional embodiment of the present application, the copper ion complexing agent is thiourea, and the stannous salt is (CH ₃ SO ₃ ) ₂ Sn.

Adding thiourea or citric acid can form stable complex ions with Cu ²⁺ and Cu ⁺ . For example, after adding thiourea, complex ions such as [Cu(NH ₂ CSNH ₂ ) ₄ ] ²⁺ , [Cu(NH ₂ CSNH ₂ ) ₄ ] ⁺ can be formed in a strongly acidic environment. Adding a copper ion complexing agent in the test solution can adjust the electrode potential, so that Sn ²⁺ can undergo a displacement reaction with the contacted Cu and precipitate metallic tin.

In combination with the first aspect, in an optional embodiment of the present application, the mass ratio of the copper ion complexing agent to the stannous salt is 2-4:1-2;

Optionally, the test solution includes 10-20 g/L thiourea and 5-10 g/L (CH ₃ SO ₃ ) ₂ Sn.

The potentials of stannous ions and copper ions change with the addition of complexing agent. Adding copper ion complexing agent and stannous salt with a mass ratio of 2-4:1-2 in the test solution can increase the rate of substitution reaction between Sn ²⁺ ions and Cu, and rapidly precipitate metallic tin.

Utilize 10-20g/L of thiourea and 5-10g/L of (CH ₃ SO ₃ ) ₂ Sn test solution to detect whether there is glue residue in the first area of the solar cell substrate. The area can quickly observe the precipitation of metal tin, and then quickly judge whether the solar cell substrate is not clean, so as to adjust the exposure and development processes in the front stage of the copper electroplating process of the solar cell in time according to the inspection results, thereby avoiding the risk of contamination after the electroplating process. A large number of bad copper grid lines appear.

In combination with the first aspect, in an optional implementation manner of the present application, the method for covering the first area with the test solution includes: soaking the solar cell substrate in the test solution for a preset time;

Optionally, soak 3-5 solar cell substrates in the test solution at the same time;

Optional, the preset time is 5-15s;

And/or, a method of observing the color of the first zone, comprising:

Using a microscope, observe the color of the first zone.

Soak the solar cell substrate after part of the photosensitive adhesive layer has been removed in the test solution for 5-15 seconds, while ensuring that the copper metal layer not covered by the residual glue at the first area is in uniform contact with the test solution, it can also avoid the If the soaking time is too long, the inspection efficiency will be reduced. In addition, soaking the plurality of solar cell substrates after part of the photosensitive adhesive layer is removed in the test solution at the same time can reduce test errors and improve test efficiency, and the operation is simple and convenient.

In the second aspect, the embodiment of the present application provides an inspection device for the inspection method provided in the first aspect, including:

Flower basket, the inside of the flower basket is provided with a plurality of limit clips at intervals along the length of the flower basket, and the distance between two adjacent limit clips is 0.4-0.6cm, so that the space between two adjacent solar cell substrates inserted into the flower basket 0.4-0.6cm; the flower basket includes a bottom plate and side plates around the bottom plate, both the bottom plate and the side plates are hollowed out; the tank for storing the detection liquid; the flower basket can be selected to enter and exit the tank.

The test device is provided with a tank for storing the test liquid, so that the solar cell substrate to be tested can enter and exit the tank through the flower basket, and then be immersed in the liquid surface of the test liquid in the tank for a certain period of time, and then pass through the flower basket and the test liquid. Separation, so that the operator can perform subsequent detection operations.

The bottom plate and side plates of the flower basket are both hollowed out, and the distance between two adjacent limiting clips used to fix the solar cell substrate in the flower basket is 0.4-0.6cm, so that multiple solar cell substrates can pass through the flower basket When the test liquid entering the tank is below the liquid level, the surface of each solar cell substrate can be in uniform contact with the test liquid, thereby improving the test efficiency and test quality.

In conjunction with the second aspect, in an optional embodiment of the present application, at least one side of the flower basket is provided with a handle protruding from the top of the flower basket at a certain height away from the bottom plate, for pulling the flower basket into and out of the tank.

A handle is provided on one side of the flower basket, so that the operator can operate the flower basket into and out of the tank through the handle, so as to prevent the operator from contacting the test liquid in the tank, thereby improving the detection safety.

In conjunction with the second aspect, in an optional embodiment of the present application, the side plate includes a first side plate arranged along the length direction of the flower basket; The second rack; the first rack and the second rack are used to limit the two adjacent sides of the battery sheet in one-to-one correspondence.

The bottom plate and the side plate of the flower basket are respectively provided with racks, and the cells can be placed between the corresponding teeth of the two racks, so as to prevent multiple solar cell substrates in the flower basket from stacking each other.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, so It should be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

Fig. 1 is a structural schematic diagram of a solar cell;

2A is a schematic diagram of the first distribution of residual glue in the solar cell substrate after the development process of copper interconnection technology;

Fig. 2B is a schematic diagram of the second distribution of residual glue in the solar cell substrate after the development process of copper interconnection technology;

Fig. 3 is the first schematic plan view of the solar cell substrate after being uniformly contacted with the test liquid by the test method provided by the present application;

Fig. 4 is a schematic structural view of the inspection device provided by the example of the present application;

FIG. 5 is an optical image after detection of Example 1 of the present application.

Icons: 10-inspection device; 11-flower basket; 111-bottom plate; 112-side plate; 113-limit clip; 1131-first rack; 1132-second rack; 114-handle;

2-solar cell; 20-solar cell substrate; 21-copper seed layer; 22-photosensitive adhesive layer; 23-first area; 24-second area; 25-residual glue; 30-electroplated copper grid line.

Detailed ways

Embodiments of the technical solutions of the present application will be described in detail below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and therefore are only examples, rather than limiting the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the application; the terms used herein are only for the purpose of describing specific embodiments, and are not intended to To limit the present application; the terms "comprising" and "having" and any variations thereof in the description of the present application and the above descriptions of the drawings are intended to cover a non-exclusive inclusion.

In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and should not be understood as indicating or implying relative importance or implicitly indicating the number, specificity, or specificity of the indicated technical features. Sequence or primary-secondary relationship. In the description of the embodiments of the present application, "plurality" means two or more, unless otherwise specifically defined.

Reference herein to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiments of the present application, the term "plurality" refers to more than two (including two), and similarly, "multi-piece" refers to more than two (including two).

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "middle", "length", "width", "thickness", "upper", "lower", "bottom" and "inner" are based on the orientation shown in the drawings Or positional relationship is only for the convenience of describing the embodiment of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a reference to the embodiment of the present application. limits.

In the description of the embodiments of this application, unless otherwise clearly specified and limited, technical terms such as "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integrated ; It can also be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present application according to specific situations.

In solar cell technology, compared with traditional P-type monocrystalline/polycrystalline solar cells, silicon-based heterojunction solar cells are the most attractive due to their high conversion efficiency, simple process flow and low temperature coefficient . Currently, one of the cutting-edge solar photovoltaic technologies is the use of copper interconnection technology to replace traditional silver paste printing.

The other biggest advantage of copper interconnection technology over traditional silver paste printing technology is that copper interconnection can be thinned. One of the core technologies of line thinning is the graphic transfer technology of wet film photosensitive adhesive. In the copper interconnection battery technology, wet film photosensitive adhesive printing, development, and electroplating are used to make the copper grid lines of the battery sheet, replacing the traditional silver paste printing technology.

In the preparation process of copper interconnection gate lines of some heterojunction cells:

(1), on the silicon base layer (the silicon base layer includes: a silicon layer (N-type silicon substrate) deposits an intrinsic amorphous silicon layer and a P-type amorphous silicon film layer on the front side, and deposits an intrinsic amorphous silicon layer and an N-type amorphous silicon layer on the reverse side. Silicon thin film layer) and transparent conductive oxide thin film layer) are deposited on the surface to form a copper seed layer 21, and then a photosensitive adhesive layer 22 is formed on the copper seed layer 21 to cover the copper seed layer 21. Hereinafter, the color of the copper seed layer 21 is named as the first color.

(2), then exposing and developing the photosensitive adhesive layer 22 in step (1), removing unnecessary photosensitive adhesive, and forming the first region 23 . In FIG. 3 , for the sake of illustration, the part that is not the first area 23 is named as the second area 24 . Copper electroplating is then performed on the first region 23 to form electroplated copper grid lines 30 .

A schematic structural diagram of the solar cell 2 is shown in FIG. 1 . The solar cell 2 includes a solar cell substrate 20 and an electroplated copper grid wire 30 .

Normally, after exposure and development, a groove structure will be formed and the copper seed layer 22 at the first region 23 will be exposed, so that electroplating on the copper seed layer 22 will thicken the copper layer in this region to form a gate line. However, after the exposure and development, the residual glue 25 will often be formed on the first region 23 of the solar cell substrate 20 due to unclean development. The schematic diagrams of the distribution of the solar cell substrate 20 where the residual glue 25 is formed due to dirty development are shown in FIG. 2A and FIG. 2B . Wherein, the second area 24 is an area where the photosensitive adhesive layer 22 has not been removed, and the first area 23 is an area formed after removing part of the photosensitive adhesive layer 22 .

Wherein, FIG. 2A shows that the first region 23 is fully covered with a layer of residual glue 25 ; FIG. 2B shows that the first region 23 is partially covered with a layer of residual glue 25 .

The residual glue 25 is a colorless and transparent organic polymer material, and it cannot be observed by the naked eye when a developing residue occurs. When the first region 23 is directly observed with the naked eye, the copper seed layer 21 under the residual glue 25 can be seen through the residual glue 25 . The existence of the residual glue 25 will cause defects such as broken grids in the electroplated copper grid lines 30 obtained by subsequent electroplating, which will seriously affect the use of the solar cell 2 .

Therefore, the solar cell substrate 20 is often inspected when the solar cell 2 is prepared using the copper interconnection technology.

In the prior art, inspection methods generally include two types:

One is, after the copper grid lines are formed by electroplating, the electroplated copper grid lines are inspected to see whether there is a broken grid or the like. However, after the electroplating is completed, there is a serious hysteresis to check whether the grid line is broken, and it cannot reflect in time whether the exposure and development process will be dirty.

Second, in order to solve the timeliness of inspection, take the film regularly after development, and then use EDX (Energy Dispersive X-Ray Spectroscopy, energy dispersive X-ray spectrometer) to scan the yellow area after development. If the C element can be scanned, it proves that the development is not clean, and the development parameters are adjusted by feedback to the development process, so as to avoid the development of the unclean. However, using EDX for elemental scanning requires sliced samples, which requires high requirements and a long time for sample preparation, and the cost of EDX equipment is high, requiring professional operators for inspection.

Based on this, the present application provides a method for inspecting the solar cell substrate 20 , using the inspection solution to uniformly contact the first region 23 formed after exposure and development of the solar cell substrate 20 . Under the action of the test liquid, the metal copper in the part of the first region 23 not covered by the residual glue 25 can chemically react with the test liquid to present a second color different from the first color of the copper metal. Therefore, it can be judged whether there is residual glue 25 by observing the color of the first region 23 .

If the adhesive residue 25 adheres to some positions of the first region 23 , the part of the copper metal covered by the adhesive residue 25 will not react with the test solution due to the blocking effect of the adhesive residue 25 , so that this part of the copper metal will be retained. Due to the transparency of the residual glue 25, after being treated with the inspection potion, the part covered by the residual glue 25 continues to present the first color of copper metal, and the part not covered by the residual glue 25 presents a second color different from the first color. color.

The inspection method of solar cell substrate 20 comprises:

S1. Cover the first region 23 with the test solution.

Please continue to refer to Fig. 3, when the first area 23 has no residual glue 25, after the test liquid is evenly covered on the first area 23, the copper metal at the first area 23 is directly in contact with the test liquid and reacts with the test liquid , the first region 23 entirely exhibits a second color different from the first color of the copper metal.

In FIG. 3 , for ease of presentation, the white stripes are the first color, and the black stripes are the second color.

When part of the first area 23 is covered with residual glue 25, after the test liquid is uniformly covered on the first area 23, due to the blocking effect of the residual glue 25, the test liquid cannot directly contact the copper metal covered by the residual glue 25 , resulting in a part of the copper metal located under the residual glue 25 not being able to react with the test solution, and continuing to present the first color. The part of the copper metal that is not covered by the residual glue 25 will react with the test liquid under direct contact with the test liquid, showing a second color different from the first color of the copper metal. That is, the first region 23 simultaneously appears in the first color and the second color.

When the first area 23 is fully covered with the residual glue 25, after the test solution is uniformly covered on the first area 23, due to the blocking effect of the residual glue 25, the test solution cannot directly contact the copper metal, and the first area 23 still presents the first area 23. one color.

This application does not limit the specific type of the test solution, and relevant personnel can ensure that the test solution can react with the copper metal in contact to present a second color different from the copper metal, and does not react with the residual glue 25 in contact. Next, make corresponding selections as required.

In a possible embodiment, the test solution includes stannous salt and copper ion complexing agent, and the pH of the test solution is not greater than 1.

The stannous ions in the stannous salt can react with the copper metal that is not covered by the residual glue 25 under the action of the copper ion complexing agent in a strongly acidic environment at the same time, and metal tin is precipitated on the surface of the copper metal of this part, It has the milky white color of metallic tin. That is, when using the test solution provided in this example to test whether there is a development defect, the second color is the milky white color of metallic tin.

Since the metal activity sequence of tin is located before that of copper, under conventional thermodynamic conditions, tin with stronger metal activity can displace copper with weaker metal activity from its salt solution, while the metal with less activity Weak copper cannot displace the more reactive tin from its salt solution. However, the test solution provided in this example is a strongly acidic solution, and the test solution includes a copper ion complexing agent. The copper ion complexing agent can form stable complex ions with the Cu ²⁺ and Cu ⁺ in the first region 23 that it contacts, and change the electrode potential of the reaction, thereby allowing stannous ions to undergo a reduction reaction to precipitate metallic tin.

The overall reaction formula is as follows:

2Cu+Sn ²⁺ → 2Cu ⁺ +Sn

The present application does not limit the specific type of the copper ion complexing agent. In some possible implementations, the copper ion complexing agent is selected from at least one of thiourea or citric acid.

Exemplarily, the copper ion complexing agent is thiourea (CH ₄ N ₂ S). After adding thiourea, complex ions such as [Cu(NH ₂ CSNH ₂ ) ₄ ] ²⁺ , [Cu(NH ₂ CSNH ₂ ) ₄ ] ⁺ can be formed to change the electrode potential of the reaction.

Further, the stannous salt may be (CH ₃ SO ₃ ) ₂ Sn.

Alternatively, the stannous salt may be a stannous halide or stannous methanesulfonate.

Further, this application does not limit the mass ratio of copper ion complexing agent and stannous salt in the test solution. In some possible implementations, the mass ratio of thiourea to (CH ₃ SO ₃ ) ₂ Sn is 2-4: 1-2.

Exemplarily, the test solution includes 10-20 g/L thiourea and 5-10 g/L (CH ₃ SO3 ) ₂ Sn.

Exemplarily, the test solution includes 10 g/L of thiourea and 5 g/L of (CH ₃ SO 3 ) ₂ Sn.

Exemplarily, the test solution includes 20g/L thiourea and 5g/L (CH ₃ SO3 ) ₂ Sn.

Alternatively, the testing solution may include a strong acidic solution, such as concentrated sulfuric acid, concentrated hydrochloric acid or concentrated nitric acid, to corrode or oxidize the copper metal not covered by the residual glue 25 to present a second color different from that of copper. However, the corrosion process of strong acid solution is slow and the detection efficiency is low.

Or, according to the activity of the metal, a metal ion salt with a lower metal activity than copper can be added to the test solution. For example, the test solution can include a silver ion salt solution or a platinum ion salt solution.

Further, the present application does not limit how to make the test liquid cover the first area 23. In some possible implementations, the method for making the test liquid cover the first area 23 includes:

Soak the solar cell substrate 20 in the test solution for a preset time.

Further, 3-5 pieces of solar cell substrates 20 can be soaked in the inspection solution at the same time, and multiple solar cell substrates 20 can be inspected, which can reduce inspection errors.

Optionally, multiple pieces of solar cell substrates 20 may be simultaneously immersed in the acidic test solution provided in this example containing copper ion complexing agent and stannous salt for 5-10 s.

Alternatively, a chemical test tube such as a dropper can be used to drop a sufficient amount of test liquid into the first region 23 of the solar cell substrate 20 so that the test liquid completely covers the first region 23 . Then, after a certain period of time, the test solution in the first area 23 is sucked away with a straw or absorbent cotton, etc., and dried quickly, and then followed up for observation.

Further, in order to facilitate simultaneous inspection of multiple solar cell substrates 20 , examples of the present application also provide an inspection device 10 .

Referring to Fig. 4, the testing device 10 includes:

The flower basket 11, the inside of the flower basket 11 is provided with a plurality of limit clamps 113 at intervals along the length direction of the flower basket 11, and the distance between two adjacent limit clamps is 0.4-0.6cm, so that two adjacent limit clamps inserted into the flower basket 11 The solar cell substrates 20 are separated by 0.4-0.6 cm; the flower basket 11 includes a bottom plate 111 and side plates 112 surrounding the bottom plate, both of which are hollow structures.

The tank body 12 for storing the test liquid; the flower basket 11 can optionally enter and exit the tank body 12 .

Since the bottom plate 111 and the side plate 112 of the flower basket 11 are both hollow structures, the test liquid in the tank body 12 can flow into the inside of the flower basket 11 . Moreover, the distance between two adjacent limiting clips 113 arranged inside the flower basket 11 is 0.4-0.6 cm, so when a plurality of solar cell substrates 20 are placed in the flower basket 11, two adjacent solar cells The substrates 20 can be separated by 0.4-0.6 cm, so that multiple solar cell substrates 20 can evenly contact the test solution.

The present application does not limit the specific setting form of the flower basket 11, and relevant personnel can make corresponding adjustments as required.

Exemplarily, the cavity inside the flower basket 11 is in the shape of a cube, so as to accommodate the placement of the rectangular solar cell substrate 20 .

Further, the flower basket 11 includes a rectangular bottom plate 111 and four rectangular side plates 112 surrounding the bottom plate 111 . Both the bottom plate 111 and the side plate 112 are provided with a plurality of through holes at intervals to increase the fluidity of the test liquid. Alternatively, a rectangular through hole can be opened in the middle of the bottom plate 111 and the side plate 112 to further increase the fluidity of the test liquid flowing into the flower basket 11 .

The present application does not limit the specific arrangement of the limiting clip 113. In some possible implementations, the limiting clip 113 includes a first rack 1131 disposed on the inner wall of the bottom plate 111, and a second tooth disposed on one of the side plates 112. The bar 1132 ; the first rack 1131 and the second rack 1132 are used to limit the two adjacent sides of the solar cell substrate 20 in one-to-one correspondence.

Further, a third rack can be provided on another side plate 112 opposite to one of the side plates 112 provided with the second rack 1132 . The corresponding teeth of the three racks are used to jointly limit the three sides of the solar cell substrate 20 .

Further, in order to facilitate the operator to lift the flower basket 11 and prevent the operator from coming into contact with the test liquid in the tank body 12, in a possible implementation manner, one or more side plates 112 of the flower basket 11 can be provided with expenditure The handle 114 of the side panel.

The present application does not limit the specific arrangement form of the tank body 12, and relevant personnel can make corresponding adjustments as required.

In some possible implementations, a stirring member may be provided in the tank body 12 to properly stir the test solution and disperse it evenly.

Further, a heating element can be provided at the tank body 12 to properly heat the testing liquid in the tank body 12 and increase the reaction rate between the testing liquid and metallic copper.

Further, for the convenience of subsequent observation, the inspection device 10 provided in this example also includes a drying element and a microscope. The drying part is used for drying the soaked battery slices.

S2. Observe the color of the first area 23 of copper, and judge whether there is glue residue in the first area 23 according to whether the color of the first area 23 changes.

If the entire color of the first area 23 is the second color, it means that the first area 23 has no residual glue 25 ; if the first color remains in the first area 23 , it means that the first area 23 has residual glue 25 .

Wherein, if all the colors of the first region 23 are the second color, it means that all the colors of the region to be detected coated with the test liquid are the second color. For example, the region to be detected is a quadrangle, and the test liquid completely covers the quadrangle during the test. Then, observe the colors within the area of the quadrilateral. If all of the quadrangular area is the second color, it means that there is no residual glue 25 in the quadrangular area to be detected.

Similarly, if part of the first area 23 is the second color, it means that the second color appears in the quadrilateral area to be detected. The simultaneous appearance of the first color and the second color in the quadrangular area indicates that there is residual glue 25 .

If the observed first region 23 is entirely of the first color of metallic copper, it indicates that the first region 23 is completely covered with a layer of residual glue 25 .

If it is observed that the first area 23 is all of the second color, for example, all of it is milky white of metal tin, it means that there is no glue residue 25 in the first area 23 .

If it is observed that the first region 23 has both the first color of metallic copper and the second color of metallic tin, it indicates that there is adhesive residue 25 in part of the first region 23 .

Further, the present application does not limit how to observe the color of the first region 23. In some possible implementations, the method of observing the color of the first region 23 includes:

Use an industrial microscope or a magnifying glass to observe the color of the first region 23 .

Alternatively, the operating operator can perform direct visual inspections.

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all conventional products that could be purchased from the market.

Example 1

Embodiment 1 provides a kind of inspection method of solar cell substrate 20, comprising:

(1) Soak the exposed and developed solar cell substrate 20 in the test solution for 5 seconds, then take out the solar cell substrate 20 and dry it; wherein, the test solution is 10 g/L (CH ₃ SO ₃ ) ₂ Sn and 5 g /L of CH ₄ N ₂ S, the pH of the test solution is 1.

(2) Place the solar cell substrate 20 treated in step (1) on the stage of an optical microscope, and observe the color of the first region 23 of the solar cell substrate 20 . The optical image of the solar cell substrate 20 is shown in FIG. 5 , wherein the optical image can be divided into three layers from top to bottom, the upper and lower layers are the second region 24 , and the middle layer is the first region 23 .

In Fig. 5, the first color of the copper seed layer 21 is shown in the black line frame with residual glue 25 attached (due to the existence of the transparent residual glue 25, the optical image taken is relatively darker than the surface of the growth tin metal. blurred), indicating that there is partially residual glue 25 at the detection area.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims (10)

1. An inspection method for a solar cell substrate, the solar cell substrate comprising a copper seed layer and a photosensitive adhesive layer laminated; the partial region of the solar cell substrate is processed to remove the photosensitive adhesive layer, Forming a first area; the inspection method is used to inspect whether there is transparent residual glue in the first area; it is characterized in that the inspection method includes: Cover the first region with the test solution, and observe the color of the first region; wherein, the test solution contains a substance that can react with copper and change the color of the copper into a second color; the test solution Covering before the first area, the first area is a first color; Judging whether there is the residual glue in the first region according to whether the color of the first region changes completely: if the first color remains in the first region, it means that the first region has the residual glue . 2 . The inspection method of a solar cell substrate according to claim 1 , wherein the first region is used for electroplating and thickening to form electroplated copper grid lines. 3 . 3. The inspection method of a solar cell substrate according to claim 1, wherein if all the colors of the first region are the second color, it means that the first region does not have the residual glue; All the colors of the first area are the first color, which means that the first area is completely covered with the residual glue; if the color of the first area includes the first color and the second color, it means that the first area is completely covered with the residual glue; Part of the first region is covered with the residual glue. 4. The inspection method of a solar cell substrate according to claim 1, wherein the inspection solution comprises a stannous salt and a copper ion complexing agent, and the pH of the inspection solution is not more than 1; Optionally, the copper ion complexing agent is selected from at least one of thiourea and citric acid. 5 . The inspection method for solar cell substrates according to claim 4 , wherein the copper ion complexing agent is the thiourea, and the stannous salt is (CH ₃ SO ₃ ) ₂ Sn. 6. the inspection method of solar cell substrate according to claim 5, is characterized in that, the mass ratio of described copper ion complexing agent and described stannous salt is 2-4:1-2; Optionally, the test solution includes 10-20 g/L of the thiourea and 5-10 g/L of the (CH ₃ SO ₃ ) ₂ Sn. 7. The inspection method for a solar cell substrate according to any one of claims 1-6, wherein the method for covering the first region with the inspection liquid comprises: soaking the solar cell substrate in the test solution for a preset time; Optionally, soak 3-5 pieces of the solar cell substrate in the test solution at the same time; Optionally, the preset time is 5-15s; And/or, the method for observing the color of the first region includes: Using a microscope, observe the color of the first region. 8. An inspection device for the inspection method of a solar cell substrate according to any one of claims 1-7, wherein the inspection device comprises: A flower basket, the inside of the flower basket is provided with a plurality of limit clips at intervals along the length direction of the flower basket, and the distance between two adjacent limit clips is 0.4-0.6cm, so that the corresponding ones inserted into the flower basket The distance between two solar cell substrates is 0.4-0.6cm; the flower basket includes a bottom plate and side plates surrounding the bottom plate, and the bottom plate and the side plates are hollow structures; A trough for storing the test solution; the flower basket can optionally enter and exit the trough. 9. The inspection device according to claim 8, characterized in that, at least one side of the flower basket is provided with a handle protruding from the top of the flower basket at a predetermined height away from the bottom plate for pulling the flower basket. The flower basket enters and exits the tank body. 10. The inspection device according to claim 8, wherein the side plate includes a first side plate arranged along the length direction of the flower basket; the limit clip includes a first side plate arranged on the inner wall of the bottom plate A rack, and a second rack arranged on the first side plate; the first rack and the second rack are used to limit adjacent two sides of the solar cell substrate in one-to-one correspondence.

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