KR101626164B1 - Solar cell and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a solar cell and a method of manufacturing the same, and a solar cell according to an aspect of the present invention includes a substrate; And a texturing surface located on one side of the substrate, the texturing surface having a plurality of semicircular cross-sectional depressions. The solar cell having such a configuration includes a step of disposing a mask on the substrate, in which a plurality of hole patterns are formed in one slit; Irradiating the linear laser beam having a constant line width to the mask in such a manner that the longitudinal direction of the laser beam is aligned with the longitudinal direction of the slit; Forming a plurality of concave portions on the surface of the substrate at positions corresponding to the plurality of hole patterns by removing a portion of the surface of the substrate by the linear laser beam that has passed through the plurality of hole patterns; And a step of irradiating the linear laser beam a plurality of times while adjusting a relative position of the mask and the substrate, thereby completing a texturing surface including the plurality of recesses in the substrate have.

Description

SOLAR CELL AND MANUFACTURING METHOD THEREOF BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a solar cell and a method of manufacturing the same.

With the recent depletion of existing energy resources such as oil and coal, interest in alternative energy to replace them is increasing. Among them, solar cells produce electric energy from solar energy, and they are attracting attention because they have abundant energy resources and there is no problem about environmental pollution.

Solar cells are classified into crystal systems, amorphous systems, compound systems and the like depending on the kind of materials used, and crystal silicon solar cells are classified into monocrystalline type and polycrystalline type.

The single crystal silicon solar cell has a disadvantage in that it is easy to achieve high efficiency because of good quality of the substrate, but the production cost of the substrate is large. On the other hand, polycrystalline silicon solar cell has a disadvantage that it is difficult to achieve high efficiency because the quality of the substrate is relatively inferior to that of the monocrystalline silicon solar cell. However, recently, the quality of the substrate has been improved and the process technology has been advanced.

As one of the methods for increasing the efficiency of a polycrystalline silicon solar cell, there has been a method of reducing the reflectivity of light incident on the light receiving surface by forming concave and convex on the surface of the light receiving surface of the substrate

SUMMARY OF THE INVENTION The present invention provides a solar cell with improved efficiency.

Another aspect of the present invention is to provide a method of manufacturing a solar cell capable of shortening a process time.

A solar cell according to an aspect of the present invention includes a substrate; And a texturing surface located on one side of the substrate, the texturing surface having a plurality of semicircular cross-sectional depressions.

The plurality of recesses are formed to a diameter of 10 탆 or less, and the emitter portion is located on the lower side or the upper side of the texturing surface, and the surface of the emitter portion is formed in the same shape as the texturing surface.

The plurality of recesses may be arranged in a plurality of rows or may be randomly arranged.

When a plurality of concave portions are arranged in a plurality of rows, a plurality of concave portions located in any one of the rows may be formed to have the same size or at least two or more different sizes.

In a case where a plurality of concave portions located in any one row are formed to have the same size, the plurality of concave portions may be formed in different sizes from the plurality of concave portions located in different rows, or may be formed to have the same size as each other.

When a plurality of concave portions located in any one row are formed to have different sizes from a plurality of concave portions located in neighboring rows, a plurality of concave portions located in any one of the rows are arranged in a row direction They can be arranged not parallel to each other.

When a plurality of concave portions located in a plurality of rows are formed to have the same size as each other, a plurality of concave portions located in any one row are arranged in parallel to each other in a row direction with a plurality of concave portions located in neighboring rows, Lt; / RTI >

When a plurality of concave portions located in any one of the plurality of rows are formed to have at least two different sizes, the size of the concave portion located at the central portion of the substrate among the plurality of concave portions located in any one row, The size of the concave portion located in the portion can be formed differently.

For example, the size of the recess located at the center of the substrate may be larger than the size of the recess located at the edge of the substrate. At this time, the size of the concave portion may gradually increase from the edge portion of the substrate toward the center portion of the substrate.

Alternatively, the size of the concave portion located at the edge portion of the substrate may be larger than the size of the concave portion located at the center portion. In this case, the size of the concave portion may gradually increase from the center portion of the substrate to the edge portion of the substrate.

When a plurality of concave portions are randomly arranged, the plurality of concave portions may be formed to have the same size or at least two or more different sizes.

The solar cell having such a configuration includes a step of disposing a mask on the substrate, in which a plurality of hole patterns are formed in one slit; Irradiating the linear laser beam having a constant line width to the mask in such a manner that the longitudinal direction of the laser beam is aligned with the longitudinal direction of the slit; Forming a plurality of concave portions on the surface of the substrate at positions corresponding to the plurality of hole patterns by removing a portion of the surface of the substrate by the linear laser beam that has passed through the plurality of hole patterns; And a step of irradiating the linear laser beam a plurality of times while adjusting a relative position of the mask and the substrate, thereby completing a texturing surface including the plurality of recesses in the substrate have.

In the above manufacturing method, an excimer laser having a wavelength of 500 nm or less can be used as the linear laser beam, and the line width of the laser beam is larger than the width of the hole pattern and smaller than or equal to the width of the slit And the semicircular concave portion can be formed to a size of 10 mu m or less.

After forming the texturing surface, an emitter portion may be further formed on the lower side or the upper side of the texturing surface.

Alternatively, the solar cell having the above-described configuration may be provided with a mask having a slit including a first region where a plurality of hole patterns are formed and a second region where a transflective pattern for reducing the intensity of the laser beam is formed, Placing; Forming an impurity layer on the substrate surface to form an emitter portion; Irradiating the linear laser beam having a constant line width to the mask in such a manner that the longitudinal direction of the laser beam is aligned with the longitudinal direction of the slit; A part of the surface of the substrate is removed by the linear laser beam having passed through the plurality of hole patterns to form a plurality of recesses on the surface of the substrate corresponding to the plurality of hole patterns, Activating an impurity of the impurity layer by the linear laser beam to diffuse the impurity into the substrate at a position corresponding to the transflective pattern; And irradiating the linear laser beam a plurality of times while adjusting a relative position of the mask and the substrate, thereby completing a texturing surface and an emitter portion on the substrate.

In the above manufacturing method, an eximer laser having a wavelength of 500 nm or less can be used as the linear laser beam, and the line width of the laser beam is set to a size capable of irradiating the hole pattern and the semi- And the width of the slit may be less than or equal to the width of the slit, and the hemispherical recess may be formed to a size of 10 mu m or less.

Adjusting the relative position of the mask and the substrate may be performed by transporting the substrate by the width of the first region before irradiating the laser beam and the size of the transflective pattern is formed to be equal to the size of the first region .

According to this feature, it is possible to simultaneously form a plurality of concave portions by a linear laser beam having a constant line width.

Therefore, since the size of the concave portion can be formed to be as small as 10 mu m or less as compared with the conventional method of forming the concave portion by performing the etching process using the mask pattern after forming the mask pattern using the spot laser, It is possible to form a large amount of concave portions, thereby effectively reducing the light reflection of the textured surface.

It is also possible to suppress the reduction in the uniformity of the concave pattern due to the pulse-to-pulse variation of the laser and shorten the processing time.

In addition, since the texturing surface forming process and the emitter forming process can be performed at the same time, the process time can be further shortened.

1 is a partial perspective view of a solar cell according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the solar cell shown in FIG. 1 taken along line II-II.
3-7 are partial plan views of a substrate showing textured surfaces according to various embodiments of the present invention.
Figures 8 and 9 are partial plan views of the mask used to form the textured surface.
Figure 10 is a partial plan view of the masking surface and the mask used to form the emitter portion.
11 is a conceptual diagram showing an embodiment of a solar cell manufacturing apparatus.
FIG. 12 is a process diagram for forming a textured surface using the mask of FIG. 8 or FIG. 9. FIG.
13 is a process diagram for forming a textured surface and an emitter portion using the mask of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. Like parts are designated with like reference numerals throughout the specification. When a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case directly above another portion but also the case where there is another portion in between.

Conversely, when a part is "directly over" another part, it means that there is no other part in the middle. In addition, when a part is formed as "whole" on another part, it includes not only the part formed on the entire surface (or the entire surface) of the other part but also the part not formed on the edge part.

Hereinafter, a solar cell according to an embodiment of the present invention will be described with reference to the accompanying drawings.

First, a solar cell according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. FIG.

FIG. 1 is a partial perspective view of a solar cell according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II of the solar cell shown in FIG.

Referring to the drawings, a solar cell according to an embodiment of the present invention includes a substrate 10, an emitter section 20 disposed on a front surface (hereinafter referred to as a 'light receiving surface') of a substrate 10 to which light is incident, An antireflection film 30 located on the emitter 20, a plurality of front electrodes 40 electrically connected to the emitter 20, a plurality of front electrode housings physically and electrically connected to the front electrodes 40, A rear electrode 60 positioned on the rear surface of the substrate 10, a rear electrode current collector 70 positioned on the rear surface of the rear electrode 60, and a rear electrode 60 and a substrate 10, And a back surface field (BSF) portion 80 positioned between the first and second electrodes.

The substrate 10 is a semiconductor substrate made of silicon of the first conductivity type, for example, p-type conductivity type. The silicon may be monocrystalline silicon, polycrystalline silicon or amorphous silicon.

When the substrate 10 has a p-type conductivity type, it contains an impurity of a trivalent element such as boron (B), gallium, indium or the like. Alternatively, however, the substrate 10 may be of the n-type conductivity type. When the substrate 10 has an n-type conductivity type, the substrate 10 may contain impurities of pentavalent elements such as phosphorus (P), arsenic (As), antimony (Sb)

Such a substrate 10 includes a first texturing surface 12 to reduce light reflectivity on the light receiving surface.

The texturing surface 12 has a plurality of recesses 14 formed on the surface of the substrate 10 to form a honeycomb structure. The recesses 14 have a semicircular cross-sectional shape, D) is formed to be 10 mu m or less.

The texturing surface 12 will be described in more detail with reference to the accompanying drawings.

3-7 are partial plan views of substrate 10 showing various embodiments of texturing surface 12.

Referring to FIG. 3, a plurality of concave portions 14a forming the texturing surface 12 in the present embodiment are arranged in a plurality of rows (..., _Rn , _{Rn + 1} , _{Rn + 2} , R _{n +3} , R _{n +4} , ...).

The plurality of concave portions 14a located in the respective rows are formed to have the same size as each other. As a whole, all of the concave portions are formed to have the same size as each other. And are arranged parallel to each other in the row direction (X-X ') with the concave portions.

Referring to FIG. 4, the plurality of concave portions are formed to have the same size as each other, and the plurality of concave portions located in any one row are arranged in the row direction X-X ' Are arranged in a non-parallel manner.

5, the plurality of recesses 14a located in the respective rows are formed to have the same size as each other, but the plurality of recesses 14b located in any one of the rows has a plurality of recesses 14a located in other rows, As shown in FIG.

For example, the plurality of recesses 14b located in the middle row of FIG. 5 are formed to be larger than the plurality of recesses 14a located in other rows. The number of rows in which the concave portions 14b largely formed in comparison with the other concave portions are arranged is not limited, and the arrangement position can be freely changed. According to such a configuration, the plurality of concave portions 14b located in any one row are arranged in parallel with each other in the row direction (X-X ') from the plurality of concave portions 14a located in the neighboring rows.

Referring to Fig. 6, at least two concave portions 14a and 14b having different sizes are arranged in one row. For example, the concave portion 14b located in the second and third rows among the plurality of concave portions located in the second row () shown in Fig. 6 is larger than the concave portion 14a located in the other row .

The number of the concave portions 14b formed to be larger than the other concave portions 14a is not limited, and the arrangement position can be freely changed.

7, when a plurality of concave portions located in any one of a plurality of rows are formed to have at least two different sizes, the center portion 10a of the substrate 10 among the plurality of concave portions located in any one row, The size of the concave portion located at the edge portion 10b of the substrate 10 and the size of the concave portion located at the edge portion 10b of the substrate 10 may be different from each other.

For example, the size of the concave portion located at the center portion 10a of the substrate 10 may be larger than the size of the concave portion located at the edge portion 10b of the substrate 10. At this time, the size of the concave portion may gradually increase from the edge portion 10b of the substrate 10 toward the central portion 10a.

The size of the concave portion located at the edge portion 10b of the substrate 10 may be larger than the size of the concave portion located at the center portion 10a, 10a toward the edge portion 10b.

Although only a few embodiments of the textured surface 12 have been described above, the present invention is not limited to the above embodiment, and can be modified into various forms.

More specifically, the plurality of concave portions may be arranged in a plurality of rows or may be randomly arranged.

When a plurality of concave portions are arranged in a plurality of rows, a plurality of concave portions located in any one of the rows may be formed to have the same size or at least two or more different sizes.

In a case where a plurality of concave portions located in any one row are formed to have the same size, the plurality of concave portions may be formed in different sizes from the plurality of concave portions located in different rows, or may be formed to have the same size as each other.

When a plurality of concave portions located in any one row are formed to have different sizes from a plurality of concave portions located in neighboring rows, a plurality of concave portions located in any one of the rows are arranged in a row direction They can be arranged not parallel to each other.

When a plurality of concave portions located in a plurality of rows are formed to have the same size as each other, a plurality of concave portions located in any one row are arranged in parallel to each other in a row direction with a plurality of concave portions located in neighboring rows, Lt; / RTI >

When a plurality of concave portions located in any one of the plurality of rows are formed to have at least two different sizes, the size of the concave portion located at the central portion of the substrate among the plurality of concave portions located in any one row, The size of the concave portion located in the portion can be formed differently.

For example, the size of the recess located at the center of the substrate may be larger than the size of the recess located at the edge of the substrate. At this time, the size of the concave portion may gradually increase from the edge portion of the substrate toward the center portion of the substrate.

Alternatively, the size of the concave portion located at the edge portion of the substrate may be larger than the size of the concave portion located at the center portion. In this case, the size of the concave portion may gradually increase from the center portion of the substrate to the edge portion of the substrate.

When a plurality of concave portions are randomly arranged, the plurality of concave portions may be formed to have the same size or at least two or more different sizes.

On the other hand, the emitter portion 20 is located inside the substrate 10 below the texturing surface 12 having the above-described configuration. Although not shown, the emitter portion 20 may be located above the textured surface 12.

The emitter section 20 is a p-n junction with the semiconductor substrate 10 as an impurity section having a second conductivity type opposite to the conductivity type of the substrate 10, for example, an n-type conductivity type. At this time, since the emitter 20 is formed by diffusion of the impurities into the substrate 10, the emitter 20 formed on the front surface of the substrate 10 has the same shape as the textured surface of the substrate 10. That is, the lower surface of the emitter portion 20 has a concave portion having the same shape as the texturing surface.

Due to the built-in potential difference due to the pn junction, the electron-hole pairs, which are charges generated by the light incident on the substrate 10, are separated into electrons and holes, electrons move toward the n- Moves toward the p-type. Therefore, when the substrate 10 is a p-type and the emitter 20 is n-type, the separated holes move toward the substrate 10, and the separated electrons move toward the emitter 20, Becomes a majority carrier, and the electrons in the emitter section 20 become a majority carrier.

When the substrate 10 has an n-type conductivity type, the emitter portion 20 has a p-type conductivity type because the emitter portion 20 forms a p-n junction with the substrate 10. In this case, the separated electrons move toward the substrate 10 and the separated holes move toward the emitter 20.

When the emitter section 20 has an n-type conductivity type, the emitter section 20 dopes impurities of pentavalent elements such as phosphorus (P), arsenic (As), antimony (Sb) And may be formed by doping an impurity of a trivalent element such as boron (B), gallium (Ga), indium (In) or the like on the substrate 10 when the p-type conductive type is employed.

An antireflection film 30 made of a silicon nitride film (SiNx) or a silicon oxide film (SiOx) is formed on the emitter portion 20. The antireflection film 30 reduces the reflectivity of light incident on the solar cell, increases the selectivity of a specific wavelength region, and increases the efficiency of the solar cell.

A plurality of front electrodes 40 are disposed on the emitter section 20 and are electrically connected to the emitter section 20 and extend in a predetermined direction in a state of being spaced apart from each other. The plurality of front electrodes 40 collects charges (electrons) that have migrated toward the emitter section 20 and outputs them to an external device.

The plurality of front electrodes 40 may be formed of at least one selected from the group consisting of Ag, Ni, Cu, Al, Sn, Zn, In, Ti, Au), and combinations thereof, and may include at least one conductive metal material other than the conductive metal material.

A plurality of front electrode current collectors 50 are formed on the emitter electrode 20 in a direction crossing the front electrode 40. Since the front electrode current collector 50 is electrically and physically connected to the front electrode 40, the electric charge moving to the front electrode 40 is output to the external device through the front electrode current collector 50.

The rear electrode 60 is formed substantially on the entire rear surface of the substrate 10. The rear electrode 60 includes a conductive material such as aluminum (Al), is electrically connected to the substrate 10, collects charges (holes) moving from the substrate 10 side, and outputs the collected charges to an external device .

The back electrode 60 may be formed of a metal such as nickel (Ni), copper (Cu), silver (Ag), tin (Sn), zinc (Zn), indium (In), titanium (Ti) And combinations thereof, and may include at least one conductive material other than the conductive material.

The rear electrode current collector 70 is located on the rear surface of the rear electrode 60. The rear electrode current collector 70 is formed in the same direction as the front electrode current collector 50 and the electric charge moved to the rear electrode 60 is output to the external device through the rear electrode current collector 70.

The rear electric field portion 80 located between the rear electrode 60 and the substrate 10 is a region doped with the same conductivity type as that of the substrate 10 at a higher concentration than the substrate 10, .

The rear electric field 80 interferes with the electron movement toward the backside of the substrate 10 due to the potential barrier formed due to the difference in impurity concentration between the substrate 10 and the rear electric field 80, And the holes are recombined to disappear.

Hereinafter, a method of manufacturing a solar cell according to an embodiment of the present invention will be described with reference to FIGS. 8 to 13. FIG.

FIGS. 8 and 9 are partial plan views of the mask used for forming the textured surface, FIG. 10 is a partial plan view of the mask used for forming the textured surface and the emitter portion, and FIG. Fig.

FIG. 12 is a process chart for forming a textured surface using the mask of FIG. 8 or FIG. 9, and FIG. 13 is a process diagram for forming a textured surface and an emitter by using the mask of FIG.

Referring to FIGS. 8, 11 and 12, the mask 110 of the present embodiment includes a plurality of hole patterns 114 in one slit 112. The hole patterns 114 are arranged in a single row, and each of the hole patterns 114 is formed with a size (diameter) of 10 mu m or less.

The mask 110 having such a structure is disposed between the first reflection mirror 220 and the second reflection mirror 230 in the solar cell manufacturing apparatus shown in FIG.

The laser beam LB output from the laser source 210 is a linear laser beam having a constant line width and is an excimer laser having a wavelength of 500 nm or less. The shape of the mask 110, The same or similar.

The line width of the laser beam LB may be larger than the size (diameter) of the hole pattern 114 and smaller than or equal to the width W of the slit 112. For example, the linear laser beam LB may have a line width of several mu m to 20 mu m. At this time, the line width of the laser beam LB can be adjusted using a short axis beam cutter (not shown).

The length of the laser beam LB is preferably equal to or slightly smaller than the length of the substrate 10 or the mask 110. The length of the laser beam LB is set at a position above the mask 110 And can be adjusted using a beam cutter (not shown) disposed.

The mask 110 is moved such that the longitudinal direction of the laser beam LB and the longitudinal direction of the slit 112 are aligned so that only a part of the linear laser beam LB can pass through the hole pattern 114 of the mask 110. [ And is disposed between the first mirror 220 and the second mirror 230 in one state.

The laser beam LB that has passed through the hole pattern 114 of the mask 110 among the linear laser beams LB output from the laser source 210 and reflected by the first reflection mirror 220 Is irradiated to the substrate 10 via the second reflection mirror 230 and the third reflection mirror 240.

Therefore, a portion of the surface of the substrate 10 to which the laser beam LB is irradiated is partially removed, thereby forming concave portions (see Figs. 3 to 6, 14a and 14b) of a circular cross-sectional shape.

As shown in FIG. 12, the recesses (see FIGS. 3 to 6, 14a and 14b) are arranged in a row on the surface of the substrate 10 in the same manner as the hole patterns 114 formed in the mask 110 do.

Thereafter, the substrate 10 is transported a predetermined distance, and then the above-described operation is repeated to form a plurality of recesses on the entire surface of the substrate 10, thereby forming a texturing surface (Figs. 2 to 6 12) is completed.

In Fig. 12, the white circles represent the recesses formed in the previous step, and the black circles represent the recesses formed in the present step.

The mask shown in Fig. 8 can be used to form the texturing surface of Figs. 3 and 4 of the above embodiments.

The mask 120 of FIG. 9 includes one slit 122 in which hole patterns 124a and 124b of different sizes are arranged in two rows, as shown in the figure.

Therefore, the mask 120 having such a configuration is used to form the texturing surface of the embodiment in which the recesses 14b in one row are formed to be larger than the recesses 14a in the other row, as shown in Fig. 5 It is possible to use.

On the other hand, although not shown, hole patterns formed in the mask may have hole patterns of different sizes in one row. The mask of such a configuration can be used to form a textured surface having recesses of different sizes in at least one column, as shown in Figs. 6 and 7. Fig.

After the texturing surface is formed as described above, an emitter portion (see FIG. 1 and FIG. 2) is formed on the upper or lower side of the texturing surface.

In the case where the emitter portion is formed on the upper side of the texturing surface, a method of depositing a different silicon layer containing impurities (an amorphous layer or the like when the substrate is polycrystalline) is deposited on the textured surface.

When the emitter layer is formed on the lower side of the texturing surface, a method of coating the impurity layer on the texturing surface and then diffusing the impurities into the substrate through heat treatment may be used.

Hereinafter, a solar cell manufacturing method according to another embodiment of the present invention will be described with reference to FIGS. 10, 11, and 13. FIG.

The mask 130 shown in Fig. 10 has one slit 132 divided into a first area A1 and a second area A2. In the first area A1, a plurality of hole patterns 134 And a transflective pattern 136 is formed in the second area A2.

The semi-transparent pattern 136 is a pattern for activating impurities of the impurity layer by reducing the intensity or intensity of the laser beam LB to 30% to 50%.

At this time, it is preferable that the semi-transparent pattern 136 is formed to have the same size as the first area A1.

The line width of the linear laser beam LB is preferably larger than a size capable of simultaneously irradiating the hole pattern 134 and the transflective pattern 136 and smaller than or equal to the width of the slit 132 Do.

On the other hand, in this embodiment, an operation of forming a textured surface in a state in which the surface of the substrate 10 is coated with the impurity layer 22 for forming the emitter portion (see FIGS. 1 and 2) 20 is proceeded.

More specifically, in the laser beam LB reflected by the first reflecting mirror 220, concaves of the first row are formed on the surface of the substrate 10 by the laser beam passing through the hole pattern 134 do.

Then, the substrate 10 is transferred by the width of the first area A1, and the laser beam LB is again irradiated.

When the laser beam LB is irradiated, the laser beam LB having passed through the transflective pattern 136 is irradiated onto the substrate region of the first row, so that impurities of the impurity layer 22 coated on the region are activated, 10). Therefore, the emitter portion 20 is formed in this region. Of course, in this region, a plurality of recesses are already formed in the previous process.

And the concave portion 14a of the second row is formed by the laser beam LB passing through the hole pattern 134. [

When the substrate transfer and the irradiation of the laser beam are repeated as described above, the texturing surface 12 is formed on the surface of the substrate 10, and the emitter 20 is formed in the substrate 10 below the texturing surface 12 do.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

10: substrate 12: textured surface
20: Emitter section 30: Antireflection film
40: front electrode 50: front electrode current collector
60: rear electrode 70: back electrode current collector
80: rear electric field 110, 120, 130: mask
210: laser source 220, 230, 240: reflection mirror

Claims (39)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete Disposing a mask having a plurality of hole patterns on one slit on a substrate;
Irradiating the linear laser beam having a constant line width to the mask in such a manner that the longitudinal direction of the laser beam is aligned with the longitudinal direction of the slit;
A plurality of concave portions having the same diameter as the hole pattern are formed on the surface of the substrate at positions corresponding to the plurality of hole patterns by removing a part of the surface of the substrate by the linear laser beam having passed through the plurality of hole patterns ; And
Completing a texturing surface including the plurality of recesses in the substrate by irradiating the linear laser beam a plurality of times while adjusting a relative position of the mask and the substrate,
Wherein the method comprises the steps of: 17. The method of claim 16,
Wherein an excimer laser having a wavelength of 500 nm or less is used as the linear laser beam. 17. The method of claim 16,
Wherein the line width of the laser beam is larger than the width of the hole pattern and smaller than or equal to the width of the slit. 17. The method of claim 16,
Wherein the concave portion is formed to a size of 10 mu m or less. 17. The method of claim 16,
And forming an emitter portion on the lower side or the upper side of the texturing surface after forming the texturing surface. Forming an impurity layer on the substrate surface to form an emitter portion;
Disposing a mask having a slit on the impurity layer including a first region where a plurality of hole patterns are formed and a second region where a transflective pattern for reducing the intensity of the laser beam is formed;
Irradiating the linear laser beam having a constant line width to the mask in such a manner that the longitudinal direction of the laser beam is aligned with the longitudinal direction of the slit;
A part of the surface of the substrate is removed by the linear laser beam having passed through the plurality of hole patterns to form a plurality of recesses on the surface of the substrate corresponding to the plurality of hole patterns, Activating an impurity of the impurity layer by the linear laser beam to diffuse the impurity into the substrate at a position corresponding to the transflective pattern; And
Completing a texturing surface and an emitter portion on the substrate by irradiating the linear laser beam a plurality of times while adjusting a relative position of the mask and the substrate,
Wherein the method comprises the steps of: 22. The method of claim 21,
Wherein an excimer laser having a wavelength of 500 nm or less is used as the linear laser beam. 22. The method of claim 21,
Wherein the line width of the laser beam is larger than a size capable of simultaneously irradiating the hole pattern and the transflective pattern and smaller than or equal to the width of the slit. 22. The method of claim 21,
Wherein the concave portion is formed to a size of 10 mu m or less. 22. The method of claim 21,
Wherein adjusting the relative position of the mask and the substrate is performed by transferring the substrate by the width of the first region before irradiating the laser beam. 26. The method of claim 25,
Wherein the size of the semi-transparent pattern is the same as the size of the first region. 26. A solar cell produced by the manufacturing method according to any one of claims 16 to 26. 28. The method of claim 27,
Wherein the plurality of recesses are formed in a semicircular cross-sectional shape having a diameter of 10 mu m or less. 29. The method of claim 28,
Wherein the plurality of recesses are arranged in a plurality of rows. 30. The method of claim 29,
Wherein a plurality of recesses located in any one of the plurality of rows are formed to have the same size as each other. 32. The method of claim 30,
Wherein the plurality of recesses located in any one of the plurality of rows are formed to have different sizes from the plurality of recesses located in the other column. 32. The method of claim 31,
Wherein a plurality of concave portions located in any one of the plurality of rows are arranged in parallel to each other in a row direction with a plurality of concave portions located in neighboring rows. 30. The method of claim 29,
Wherein all of the plurality of recesses located in the plurality of rows are formed to have the same size as each other. 34. The method of claim 33,
Wherein a plurality of concave portions located in any one of the plurality of rows are arranged in parallel to each other in a row direction with a plurality of concave portions located in neighboring rows. 34. The method of claim 33,
Wherein a plurality of concave portions located in any one of the plurality of rows are arranged in parallel with each other in a row direction with a plurality of concave portions located in neighboring rows. 30. The method of claim 29,
Wherein the plurality of recesses located in any one of the plurality of rows are formed to have at least two different sizes. 37. The method of claim 36,
Wherein a size of the concave portion located at the central portion of the substrate and a size of the concave portion located at the edge portion of the substrate are different from each other among the plurality of concave portions located in any one of the rows. 37. The method of claim 37,
And the size of the concave portion located at the center portion is larger than the size of the concave portion located at the edge portion. 37. The method of claim 37,
And the size of the concave portion located at the edge portion is larger than the size of the concave portion located at the center portion.

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