KR20130007338A - Solar cell and method for manufacturing the same - Google Patents

Abstract

PURPOSE: A solar cell and a manufacturing method thereof are provided to improve productivity by forming a first electrode using a laser cladding process to supply conductive powder to supply conductive powder for forming the electrode and emit laser beams. CONSTITUTION: A substrate is prepared. A first semiconductor layer(100) and a second semiconductor layer(200) are formed on the substrate. An antireflection layer(300) is formed on the second semiconductor layer. Laser beams are emitted to the antireflection layer and conductive powder(400a) for forming an electrode is supplied. The antireflection layer is removed. A first electrode is formed in a region without the antireflection layer. [Reference numerals] (AA) Laser beam

Description

Solar cell and method for manufacturing the same

The present invention relates to a solar cell, and more particularly to a substrate type solar cell.

Solar cells are devices that convert light energy into electrical energy using the properties of semiconductors.

The solar cell has a PN junction structure in which a P (positive) type semiconductor and an N (negative) type semiconductor are bonded to each other. When solar light is incident on a solar cell having such a structure, holes are generated in the semiconductor by the incident solar energy. holes and electrons are generated, and the holes (+) move toward the P-type semiconductor and the electrons (-) move toward the N-type semiconductor due to the electric field generated from the PN junction. This makes it possible to produce power.

Such solar cells may be classified into thin film solar cells and substrate solar cells.

The thin film solar cell is a solar cell manufactured by forming a semiconductor in the form of a thin film on a substrate such as glass, the substrate solar cell is a solar cell manufactured by using a semiconductor material such as silicon itself as a substrate.

The substrate type solar cell has a disadvantage in that a thicker and expensive material is used as compared to the thin film type solar cell, but the cell efficiency is excellent.

Hereinafter, a conventional substrate type solar cell will be described with reference to the drawings.

1 is a schematic cross-sectional view of a conventional substrate-type solar cell.

As can be seen in Figure 1, the conventional substrate-type solar cell is a P-type semiconductor layer 10, N-type semiconductor layer 20, the anti-reflection layer 30, the front electrode 40, P ⁺ type semiconductor layer 50 And a back electrode 60.

The P-type semiconductor layer 10 and the N-type semiconductor layer 20 formed on the P-type semiconductor layer 10 form a PN junction structure of a solar cell.

The antireflection layer 30 is formed on the upper surface of the N-type semiconductor layer 20 to prevent reflection of incident sunlight.

The P ⁺ -type semiconductor layer 50 is formed on the lower surface of the P-type semiconductor layer 10 to prevent the carriers formed by the sunlight from recombining and disappearing.

The front electrode 40 extends from the top of the antireflection layer 30 to the N-type semiconductor layer 20 and the rear electrode 60 is formed on the bottom surface of the P ⁺ -type semiconductor layer 50 .

In the conventional substrate type solar cell, when sunlight is incident, electrons and holes are generated, and the generated electrons move to the front electrode 40 through the N-type semiconductor layer 20, The generated holes are moved to the rear electrode 60 through the P ⁺ -type semiconductor layer 50.

However, such a conventional substrate-type solar cell has a limitation in improving its productivity since the manufacturing process, in particular, the process of forming the front electrode 40 is complicated.

In more detail, in order to form the front electrode 40 in the related art, first, the front electrode material is coated on the antireflection layer 30 in a predetermined pattern by using a screen printing process, and then the coating is performed. One front electrode material was dried, and then a heat treatment was performed at a high temperature so that the dry front electrode material could penetrate the anti-reflection layer 30 and penetrate the N-type semiconductor layer 20.

As described above, in order to form the front electrode 40, the screen printing process, the drying process, and the heat treatment process have to be performed.

The present invention has been devised to solve the conventional problems as described above, the present invention is to provide a solar cell and a method of manufacturing the same by forming the electrode through a simpler process, the process is simple and thus productivity can be improved. The purpose.

The present invention, to achieve the above object, a step of preparing a substrate; Doping a predetermined dopant through one surface of the substrate to form a second semiconductor layer on the first semiconductor layer and the first semiconductor layer; Forming an anti-reflection layer on the second semiconductor layer; And supplying conductive powder for electrode formation while irradiating a laser beam onto the antireflection layer to remove the antireflection layer in the area irradiated with the laser beam and to form a first electrode in the area where the antireflection layer is removed. It provides a method of manufacturing a solar cell comprising a.

The irradiating of the laser beam may generate a predetermined height difference between the second semiconductor layer in the region irradiated with the laser beam and the second semiconductor layer in the region not irradiated with the laser beam.

The process of supplying the conductive powder for electrode formation while irradiating the laser beam may be made of a laser cladding process.

In the process of supplying the conductive powder for electrode formation while irradiating the laser beam, a high concentration layer may be formed in the second semiconductor layer by additionally supplying a dopant source having the same polarity as the dopant, wherein the dopant source is added. Supplying process can be performed using a separate injection device.

Before the step of supplying the conductive powder for electrode formation while irradiating the laser beam, further comprising the step of forming a dopant layer of the same polarity as the dopant on the anti-reflection layer to form a high concentration layer on the second semiconductor layer In this case, the method may further include a step of removing the remaining dopant layer after the step of supplying the conductive powder for electrode formation while irradiating the laser beam.

The preparing of the substrate may include etching a surface of the substrate into an uneven structure, and the predetermined dopant may be doped through the uneven structure surface of the substrate.

The method may further include forming a third semiconductor layer on the other surface of the first semiconductor layer on which the second semiconductor layer is not formed, and forming a second electrode on the third semiconductor layer.

The invention also includes a first semiconductor layer having a predetermined polarity; A second semiconductor layer formed on the first semiconductor layer and having a different polarity than that of the first semiconductor layer; An anti-reflection layer formed on the second semiconductor layer; And a first electrode connected to the second semiconductor layer through a contact hole formed in the anti-reflection layer, wherein the second semiconductor layer and the first electrode of the region where the first electrode is formed are not formed. There is provided a solar cell characterized in that there is a predetermined height difference between the second semiconductor layers in the region.

The first electrode supplies the conductive powder for forming an electrode while irradiating a laser beam on the antireflection layer to remove the antireflection layer in a region to which the laser beam is irradiated, and to provide the conductive powder in a region where the antireflection layer is removed. It can be filled and formed.

A high concentration layer may be further formed on the second semiconductor layer in contact with the first electrode.

One surface of the first semiconductor layer and the second semiconductor layer may be formed in an uneven structure.

A third semiconductor layer may be further formed on the other surface of the first semiconductor layer in which the second semiconductor layer is not formed, and a second electrode may be further formed on the third semiconductor layer.

According to the present invention as described above, the following effects can be obtained.

According to the present invention, the first electrode is formed by using a so-called laser cladding process for supplying the conductive powder for electrode formation while irradiating a laser beam, thereby inconvenience of having to continuously perform a screen printing process, a drying process and a heat treatment process as in the prior art. As the box is eliminated, the process becomes very simple, thereby improving productivity.

1 is a schematic cross-sectional view of a conventional substrate-type solar cell.
2A to 2F are cross-sectional views illustrating a manufacturing process of a solar cell according to an embodiment of the present invention.
3A to 3F are cross-sectional views illustrating a manufacturing process of a solar cell according to another embodiment of the present invention.
4A to 4H are cross-sectional views illustrating a manufacturing process of a solar cell according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

2A to 2F are cross-sectional views illustrating a manufacturing process of a solar cell according to an embodiment of the present invention.

First, as shown in FIG. 2A, the semiconductor substrate 100a is prepared.

The semiconductor substrate 100a may use a silicon substrate, for example, a P-type silicon substrate.

As the silicon substrate, monocrystalline silicon or polycrystalline silicon can be used. Since monocrystalline silicon has high purity and low crystal defect density, the efficiency of the solar cell is high, but the price is too high and the economical efficiency is low. Polycrystalline silicon has a relatively high efficiency But because it uses low-cost materials and processes, the production cost is low and it is suitable for mass production.

The process of preparing the semiconductor substrate 100a may include a process of etching one surface of the semiconductor substrate 100a into an uneven structure.

Although the upper surface of the semiconductor substrate 100a is etched with an uneven structure in the drawing, the present invention is not limited thereto, and the bottom surface of the semiconductor substrate 100a may also be etched with the uneven structure.

The process of etching one surface of the semiconductor substrate 100a into an uneven structure may be performed using an alkali etching method, a reactive ion etching method (RIE), an isotropic etching method using an acid solution, or a mechanical etching method. Can be.

Since the reactive ion etching method can form a uniform uneven structure on the surface of the semiconductor substrate 100a irrespective of the crystal orientation of the crystal grains, the reactive ion etching method can be easily applied to the process of forming the uneven structure on the surface of the polysilicon substrate. In particular, the application of the reactive ion etching method has the advantage that the subsequent process can be performed in the same chamber. When the reactive ion etching method is applied, Cl ₂ , SF ₆ , NF ₃ , HBr, or a mixture of two or more thereof is used as a main gas, and in some cases, Ar, O ₂ , N ₂ , He, or these A mixture of two or more of these may be used as the additive gas.

Next, as shown in FIG. 2B, a dopant is doped through the surface of the uneven structure of the semiconductor substrate 100a to form a PN junction layer including the first semiconductor layer 100 and the second semiconductor layer 200. do.

When the semiconductor substrate 100a is formed of a P-type semiconductor layer, the N-type dopant is doped to form an N-type semiconductor on one surface of the first semiconductor layer 100 and the first semiconductor layer 100. The second semiconductor layer 200 formed of a layer may be formed.

That is, the second semiconductor layer 200 doped with the N-type dopant may be formed by doping the N-type dopant to the surface of the semiconductor substrate 100a, and at this time, a predetermined portion of the semiconductor substrate 100a without the dopant is doped. The part constitutes the first semiconductor layer 100.

The doping process may be performed using a high temperature diffusion method or a plasma ion doping method.

In the step of doping the N-type dopant by using the high temperature diffusion method, POCl ₃ in the state in which the semiconductor substrate 100a is placed in a high temperature diffusion path of approximately 800 ° C. or more. Alternatively, the N-type dopant may be diffused to the surface of the semiconductor substrate 100a by supplying an N-type dopant gas such as PH ₃ .

In the step of doping the N-type dopant using the plasma ion doping method, POCl ₃ in a state in which the semiconductor substrate 100a is placed in a plasma generating device Alternatively, the plasma may be generated while supplying an N-type dopant gas such as PH ₃ . When the plasma is generated in this way, phosphorus (P) ions in the plasma are accelerated by the RF electric field and incident on one surface of the semiconductor substrate 100a to be ion doped.

After the plasma ion doping process, it is preferable to perform an annealing process for heating to an appropriate temperature. The reason is that when the annealing process is not performed, the doped ions may act as simple impurities, but when the annealing process is performed, the doped ions are combined with Si to be activated.

On the other hand, since the process of doping the dopant is performed at a high temperature, by-products such as PSG (Phosphor-Silicate Glass) can be formed on the surface of the semiconductor substrate. Since the PSG causes a problem of shielding current from the solar cell, it is preferable to remove the PSG using an etching solution or the like to increase the efficiency of the solar cell.

Next, as shown in FIG. 2C, an anti-reflection layer 300 is formed on the second semiconductor layer 200.

As the upper surface of the second semiconductor layer 200 is formed in the uneven structure, the anti-reflection layer 300 is also formed in the uneven structure.

The anti-reflection layer 300 may be formed of silicon nitride or silicon oxide using plasma CVD.

Next, as can be seen in FIG. 2d, the conductive powder 400a for electrode formation is supplied while irradiating a laser beam onto the antireflection layer 300.

The process of supplying the conductive powder 400a for electrode formation while irradiating a laser beam as described above may be performed by a laser cladding process using a predetermined laser cladding equipment 1.

The laser cladding process irradiates a metal surface with a laser beam to instantaneously generate a melt pool on the metal surface, and simultaneously supply a powdered cladding material from the outside to produce the metal from which the melt pool is produced. Laser surface modification technology to form a new cladding layer on the surface.

As such, when using the laser cladding process, which is a laser surface modification technique for a metal surface, as shown in FIG. 2E, the anti-reflection layer 300 is removed from the area irradiated with the laser beam, and the anti-reflection layer ( The first electrode 400 may be formed by filling the conductive powder 400a in a region where the 300 is removed.

The process of irradiating the laser beam may be preferably performed in a laser power range of 10 to 100 W to remove the anti-reflection layer 300 and smoothly fill the conductive powder 400a in the removed region. . In addition, the wavelength of the laser may use a green wavelength (about 532nm) or red wavelength (about 1064nm), but is not necessarily limited thereto.

On the other hand, as can be seen in Figure 2e, when the laser beam is irradiated on the anti-reflection layer 300, the anti-reflection layer 300 is removed in the area where the laser beam is irradiated and below the anti-reflection layer 300 removed The second semiconductor layer 200 may move toward the first semiconductor layer 100 under the influence of the laser beam.

That is, a predetermined height difference h may occur between the second semiconductor layer 200 in the region where the laser beam is irradiated and the second semiconductor layer 200 in the region where the laser beam is not irradiated. When the lower surface of the first semiconductor layer 100 is used as a reference, the second semiconductor layer 200 in the region where the laser beam is irradiated has a predetermined height higher than the second semiconductor layer 200 in the region where the laser beam is not irradiated. It can be formed as low as the difference (h).

The conductive powder 400a used as the material of the first electrode 400 is made of Ag, Al, Mg, Mn, Sb, Zn, Mo, Ni, Cu, a mixture of two or more thereof, or two or more alloy powders thereof. However, it is not necessarily limited thereto.

Next, as shown in FIG. 2F, a third semiconductor is formed on the other surface of the first semiconductor layer 100, more specifically, on a lower surface of the first semiconductor layer 100 in which the second semiconductor layer 200 is not formed. By forming the layer 500 and forming the second electrode 600 on the bottom surface of the third semiconductor layer 500, the manufacturing of the substrate-type solar cell according to the exemplary embodiment of the present invention is completed.

The process of forming the third semiconductor layer 500 and the second electrode 600 is a process of forming a second electrode material on the lower surface of the first semiconductor layer 100 and then heat-treating at a high temperature. Can be done.

That is, when the second electrode material is formed on the lower surface of the first semiconductor layer 100 and then heat treated at a high temperature of 850 ° C. or higher, for example, the second electrode material is formed on the lower surface of the first semiconductor layer 100. The third semiconductor layer 500 having a dopant concentration higher than the dopant concentration of the first semiconductor layer 100 may be formed. For example, when the first semiconductor layer 100 is made of a P-type semiconductor, the third semiconductor layer 500 is made of a P ⁺ type semiconductor layer. In this case, the process of forming the second electrode material may be a printing process using Ag, Al, Mg, Mn, Sb, Zn, Mo, Ni, Cu, a mixture of two or more thereof, or two or more alloy pastes thereof. Can be done.

Meanwhile, after separately forming the third semiconductor layer 500 on the bottom surface of the first semiconductor layer 100, the second electrode 600 may be formed on the third semiconductor layer 500. . In some cases, the second electrode 600 may be directly formed on the bottom surface of the first semiconductor layer 100.

Since the second electrode 600 is formed on a surface where sunlight does not enter, the second electrode 600 may be formed on the entire lower surface of the third semiconductor layer 500 as shown. However, in some cases, the second electrode 600 may be formed in a predetermined pattern without forming the second electrode 600 on the entire lower surface of the third semiconductor layer 500 in order to allow the reflected sunlight to enter the solar cell. It may be.

There is no particular order between the process of forming the first electrode 400 (the process illustrated in FIGS. 2D and 2E) and the process of forming the second electrode 600 (the process illustrated in FIG. 2F). That is, after the process of FIG. 2C, the third semiconductor layer 500 and the second electrode 600 are first formed on the lower surface of the first semiconductor layer 100, and then, using the laser cladding process as described above. It is also possible to form the first electrode 400.

As described above, the solar cell according to the embodiment of the present invention manufactured by the process according to FIGS. 2A to 2F includes the first semiconductor layer 100, the second semiconductor layer 200, the anti-reflection layer 300, and the first solar cell. The first electrode 400, the third semiconductor layer 500, and the second electrode 600 are included.

One surface of the first semiconductor layer 100 and the second semiconductor layer 200 may have a concave-convex structure, and the second semiconductor layer 200 has a different polarity from that of the first semiconductor layer 100. It is formed on the first semiconductor layer 100. The anti-reflection layer 300 is formed on the second semiconductor layer 200, and as described above, a predetermined region of the anti-reflection layer 300 is removed by a laser beam, so that the first electrode 400 and the second electrode are removed. Contact holes for electrical connection of the semiconductor layer 200 are formed. The first electrode 400 is connected to the second semiconductor layer 200 through the contact hole. The third semiconductor layer 500 is formed on the other surface of the first semiconductor layer 100 in which the second semiconductor layer 200 is not formed. The second electrode 600 is formed on the third semiconductor layer 500.

Meanwhile, as described above, under the influence of the laser beam, the second semiconductor layer 200 in the region where the first electrode 400 is formed and the second semiconductor layer in the region where the first electrode 400 is not formed ( A predetermined height difference h may occur between the 200.

Thus, according to the present invention, by forming the first electrode 400 using a so-called laser cladding process for supplying the conductive powder 400a for electrode formation while irradiating a laser beam, screen printing process, drying process and The inconvenience of having to continuously perform the heat treatment process is eliminated, making the process very simple.

In addition, when the screen printing process is used as in the related art, there is a limit in reducing the line width of the first electrode 400 due to limitations in the screen printing process. However, in the present invention, the first electrode 400 is controlled by adjusting the line width of the laser beam. There is an advantage that can reduce the line width of about 10㎛ to about 200㎛.

In addition, in the case of the present invention, the amount of the conductive powder 400a introduced to form the first electrode 400 is reduced, and thus the cost is greatly reduced.

In addition, due to the characteristics of the laser cladding process, the structure of the first electrode 400 obtained is very dense, so that physical properties may be improved, the process may be performed in the air, and the non-contact process may prevent impurities from being introduced. Can be obtained.

3A to 3F are cross-sectional views illustrating a manufacturing process of a solar cell according to another embodiment of the present invention.

First, as shown in FIG. 3A, the semiconductor substrate 100a is prepared.

The process of preparing the semiconductor substrate 100a is the same as in the above-described embodiment. That is, the semiconductor substrate 100a may be a silicon substrate, for example, a P-type silicon substrate, and the preparing of the semiconductor substrate 100a may be performed by etching one surface of the semiconductor substrate 100a into an uneven structure. It may include.

Next, as can be seen in Figure 3b, by doping a predetermined dopant through the surface of the uneven structure of the semiconductor substrate 100a, to form a PN junction layer consisting of the first semiconductor layer 100 and the second semiconductor layer 200. do.

The process of forming the PN junction layer by doping the dopant is the same as in the above-described embodiment. That is, by doping an N-type dopant using a high temperature diffusion method or a plasma ion doping method, for example, on the surface of the semiconductor substrate 100a, the first semiconductor layer 100 made of a P-type semiconductor layer and the first semiconductor layer ( A second semiconductor layer 200 made of an N-type semiconductor layer may be formed on one surface of 100.

Next, as can be seen in Figure 3c, to form an anti-reflection layer 300 on the second semiconductor layer (200). As in the above-described embodiment, the anti-reflection layer 300 may be formed of silicon nitride or silicon oxide using a plasma CVD method.

Next, as can be seen in Figure 3d, while irradiating a laser beam on the anti-reflection layer 300 to supply the conductive powder (400a) for electrode formation and further supply a dopant source (dopant source) (210a).

As described above, the process of supplying the conductive powder 400a for electrode formation while irradiating a laser beam may be performed by a laser cladding process using a predetermined laser cladding equipment 1.

The process of supplying the dopant source 210a may be performed by using a predetermined injection device 2, and the dopant source 210a may be made of powder or gas including a dopant.

In this case, the dopant source 210a has the same polarity as that of the dopant included in the second semiconductor layer 200. That is, when the N-type dopant is included in the second semiconductor layer 200, the dopant source 210a also has an N-type polarity.

As such, when the dopant source 210a is supplied together with the conductive powder 400a through the laser cladding process, as shown in FIG. 3e, the anti-reflection layer 300 is removed from the laser beam irradiated region. The first electrode 400 may be formed by filling the conductive powder 400a in the region where the anti-reflection layer 300 is removed, and the second semiconductor layer 200 by the dopant source 210a. ) May be further doped to form a high concentration layer 210.

The high concentration layer 210 may be formed in an upper region of the second semiconductor layer 200, more specifically in the region of the second semiconductor layer 200 in contact with the first electrode 400.

The formation thickness of the high concentration layer 210 may be controlled by appropriately adjusting the amount of the dopant source 210a to be supplied.

As described above, according to another exemplary embodiment of the present invention, the high concentration layer 210 is supplied to the second semiconductor layer 200 by additionally supplying the dopant source 210a by using a predetermined injection device 2 during the laser cladding process. It can be further formed, and there is an advantage that the efficiency of the solar cell can be improved accordingly.

Meanwhile, as described above, instead of supplying the dopant source 210a using the separate injection device 2, the conductive powder 400a and the dopant source through the laser cladding equipment 1. It is also possible to supply 210a together.

As in the above-described embodiment, the anti-reflective layer 300 is removed from the area irradiated with the laser beam, and the second semiconductor layer 200 under the removed anti-reflective layer 300 is affected by the laser beam. The first semiconductor layer 100 may move toward the first semiconductor layer 100, and accordingly, a predetermined distance may be formed between the second semiconductor layer 200 in the region irradiated with the laser beam and the second semiconductor layer 200 in the region not irradiated with the laser beam. Height differences may occur.

3F, the third semiconductor layer 500 is formed on the other surface of the first semiconductor layer 100, more specifically, on the lower surface of the first semiconductor layer 100, and the third semiconductor. By forming the second electrode 600 on the bottom surface of the layer 500, the manufacturing of the substrate-type solar cell according to another embodiment of the present invention is completed.

As in the above-described embodiment, the process of forming the third semiconductor layer 500 and the second electrode 600 is performed at a high temperature after forming the second electrode material on the lower surface of the first semiconductor layer 100. The heat treatment may be performed, or after the third semiconductor layer 500 is separately formed on the bottom surface of the first semiconductor layer 100, the second electrode may be formed on the third semiconductor layer 500. 600). In some cases, the second electrode 600 may be directly formed on the bottom surface of the first semiconductor layer 100.

In addition, although the second electrode 600 may be formed on the entire lower surface of the third semiconductor layer 500, in some cases, the second electrode 600 may be formed in a predetermined pattern without being formed on the entire lower surface of the third semiconductor layer 500. You may.

The solar cell according to another embodiment of the present invention manufactured by the process according to FIGS. 3A to 3F as described above, except that the configuration of the second semiconductor layer 200 is changed, according to the aforementioned FIGS. 2A to 2F It becomes the same as the substrate type solar cell manufactured by the process. That is, according to another embodiment of the present invention, by supplying the dopant source 210a together with the conductive powder 400a in the laser cladding process, to the second semiconductor layer 200 in contact with the first electrode 400 The high concentration layer 210 is further formed.

4A to 4H are cross-sectional views illustrating a manufacturing process of a solar cell according to another embodiment of the present invention.

First, as shown in FIG. 4A, the semiconductor substrate 100a is prepared.

Since the process of preparing the semiconductor substrate 100a is the same as in the above-described embodiment, repeated description thereof will be omitted.

Next, as can be seen in Figure 4b, by doping a predetermined dopant through the surface of the uneven structure of the semiconductor substrate 100a, to form a PN junction layer consisting of the first semiconductor layer 100 and the second semiconductor layer 200. do.

Since the process of forming the PN junction layer by doping the dopant is also the same as in the above-described embodiment, repeated description thereof will be omitted.

Next, as can be seen in Figure 4c, to form an anti-reflection layer 300 on the second semiconductor layer (200). Since the process of forming the anti-reflection layer 300 is also the same as in the above-described embodiment, a repeated description thereof will be omitted.

Next, as can be seen in Figure 4d, to form a dopant layer 350 on the anti-reflection layer (300).

The dopant layer 350 may be formed using a predetermined dopant powder.

The dopant layer 350 has the same polarity as that of the dopant included in the second semiconductor layer 200. That is, when the N-type dopant is included in the second semiconductor layer 200, the dopant layer 350 also has an N-type polarity.

Next, as shown in FIG. 4E, the conductive powder 400a for electrode formation is supplied while irradiating a laser beam onto the dopant layer 350.

As described above, the process of supplying the conductive powder 400a for electrode formation while irradiating a laser beam may be performed by a laser cladding process using a predetermined laser cladding equipment 1.

When the laser cladding process is used as described above, as shown in FIG. 4F, the dopant contained in the dopant layer 350 is additionally doped in the second semiconductor layer 200 in the region where the laser beam is irradiated. The layer 210 may be formed, and the conductive powder 400a is filled in the region where the anti-reflection layer 300 is removed and the anti-reflection layer 300 is removed in the region where the laser beam is irradiated. The first electrode 400 may be formed.

The high concentration layer 210 may be formed in an upper region of the second semiconductor layer 200, more specifically, in an upper region of the second semiconductor layer 200 in contact with the first electrode 400.

On the other hand, as in the above-described embodiment, the anti-reflection layer 300 is removed in the area irradiated with the laser beam and the second semiconductor layer 200 under the removed anti-reflection layer 300 is affected by the laser beam. May move toward the first semiconductor layer 100, and thus, between the second semiconductor layer 200 in the region where the laser beam is irradiated and the second semiconductor layer 200 in the region where the laser beam is not irradiated. Some height difference may occur.

Next, as can be seen in Figure 4g, the remaining dopant layer 350 is removed.

Next, as shown in FIG. 4H, a third semiconductor layer 500 is formed on the other surface of the first semiconductor layer 100, more specifically, on the lower surface of the first semiconductor layer 100, and the third semiconductor. By forming the second electrode 600 on the bottom surface of the layer 500, the manufacturing of the substrate-type solar cell according to another embodiment of the present invention is completed.

Since the process of forming the third semiconductor layer 500 and the second electrode 600 is the same as in the above-described embodiment, repeated description thereof will be omitted.

In the above, the method of forming the first electrode 400 formed in the direction in which sunlight is incident by supplying the conductive powder 400a for electrode formation while irradiating a laser beam has been described more easily. It is not limited. For example, the step of supplying the conductive powder 400a for electrode formation while irradiating the laser beam as described above also when forming the second electrode 600 formed in a predetermined pattern in the opposite direction to which sunlight is incident. Can also be used.

In addition, the foregoing description has been given of a method of forming a PN junction structure by doping an N-type dopant to a P-type semiconductor substrate based on the P-type semiconductor substrate, and then proceeding with the subsequent steps, but the present invention is not necessarily limited thereto. Also, a method of forming a PN junction structure by doping a P-type dopant to an N-type semiconductor substrate based on the N-type semiconductor substrate and then proceeding thereafter is included.

In addition, the present invention relates to a method for forming an electrode by applying a laser cladding process, it can be extended to a technique for forming an electrode pattern while etching the formed thin film layer on a substrate such as a glass substrate, a plastic substrate in addition to the semiconductor substrate. .

100a: semiconductor substrate 100: first semiconductor layer
200: second semiconductor layer 210: high concentration layer
210a: dopant source 300: antireflective layer
350: dopant layer 400: first electrode
400a: conductive powder 500: third semiconductor layer
600: second electrode

Claims (14)

Preparing a substrate;
Doping a predetermined dopant through one surface of the substrate to form a second semiconductor layer on the first semiconductor layer and the first semiconductor layer;
Forming an anti-reflection layer on the second semiconductor layer; And
Supplying conductive powder for electrode formation while irradiating a laser beam on the antireflection layer to remove the antireflection layer in the area irradiated with the laser beam and to form a first electrode in the area where the antireflection layer is removed. Method for manufacturing a solar cell comprising a. The method of claim 1,
The irradiating of the laser beam may generate a predetermined height difference between the second semiconductor layer in the region irradiated with the laser beam and the second semiconductor layer in the region not irradiated with the laser beam. Manufacturing method. The method of claim 1,
The process of supplying the conductive powder for electrode formation while irradiating the laser beam is a manufacturing method of a solar cell, characterized in that consisting of a laser cladding process. The method of claim 1,
The method of manufacturing a solar cell, characterized in that to form a high concentration layer in the second semiconductor layer by additionally supplying a dopant source of the same polarity as the dopant in the step of supplying the conductive powder for electrode formation while irradiating the laser beam. 5. The method of claim 4,
The method of additionally supplying the dopant source is a solar cell manufacturing method, characterized in that performed using a separate injection device. The method of claim 1,
Before the step of supplying the conductive powder for electrode formation while irradiating the laser beam, further comprising the step of forming a dopant layer of the same polarity as the dopant on the anti-reflection layer to form a high concentration layer on the second semiconductor layer Method for producing a solar cell, characterized in that. The method according to claim 6,
After the step of supplying the conductive powder for electrode formation while irradiating the laser beam, the method of manufacturing a solar cell further comprising the step of removing the remaining dopant layer. The method of claim 1,
The step of preparing the substrate comprises a step of etching the one surface of the substrate in an uneven structure, wherein the predetermined dopant is doped through the surface of the uneven structure of the substrate. The method of claim 1,
And forming a third semiconductor layer on the other surface of the first semiconductor layer where the second semiconductor layer is not formed, and forming a second electrode on the third semiconductor layer. Method for producing a battery. A first semiconductor layer having a predetermined polarity;
A second semiconductor layer formed on the first semiconductor layer and having a different polarity than that of the first semiconductor layer;
An anti-reflection layer formed on the second semiconductor layer; And
And a first electrode connected to the second semiconductor layer through a contact hole formed in the anti-reflection layer.
In this case, there is a predetermined height difference between the second semiconductor layer in the region where the first electrode is formed and the second semiconductor layer in the region where the first electrode is not formed. The method of claim 10,
The first electrode supplies the conductive powder for forming an electrode while irradiating a laser beam on the antireflection layer to remove the antireflection layer in a region to which the laser beam is irradiated, and to provide the conductive powder in a region where the antireflection layer is removed. Solar cell, characterized in that the fill. The method of claim 10,
A high concentration layer is further formed in the second semiconductor layer in contact with the first electrode. The method of claim 10,
One surface of the first semiconductor layer and the second semiconductor layer is a solar cell, characterized in that formed in a concave-convex structure. The method of claim 10,
A third semiconductor layer is further formed on the other surface of the first semiconductor layer where the second semiconductor layer is not formed, and a second electrode is further formed on the third semiconductor layer. .

Images