KR20120038625A

KR20120038625A - Solar cell

Info

Publication number: KR20120038625A
Application number: KR1020100100172A
Authority: KR
Inventors: 박재현
Original assignee: 엘지디스플레이 주식회사
Priority date: 2010-10-14
Filing date: 2010-10-14
Publication date: 2012-04-24
Also published as: KR101661223B1

Abstract

PURPOSE: A solar cell is provided to improve solar cell efficiency by improving light path efficiency inside of the solar cell. CONSTITUTION: A first electrode is formed on one surface which receives light of an insulating substrate. A semiconductor layer is formed on the first electrode. A second electrode(120) is formed on the semiconductor layer. A micro lens layer(200) is formed on the second electrode. The micro lens layer is comprised of a support layer, a prism layer(220), and a reflection pattern. The prism layer changes a path of light projected into a solar cell from the upper surface of the support layer.

Description

Solar cell {Solar cell}

The present invention relates to a solar cell, and in particular, to provide a solar cell that can maximize the efficiency of the solar cell.

Recently, as interest in environmental problems and energy depletion has increased, there is a growing interest in solar cells as an alternative energy with abundant energy resources, no problems with environmental pollution, and high energy efficiency.

Solar cells can be divided into solar cells that generate steam required to rotate turbines using solar heat and solar cells that convert sunlight into electrical energy using the properties of semiconductors.

Among them, researches on photovoltaic cells (hereinafter, referred to as solar cells) in which electrons of p-type semiconductors generated by absorbing light and holes of n-type semiconductors are converted into electrical energy are being actively conducted.

1 is a schematic diagram illustrating a concept of driving a general solar cell, and FIG. 2 is an enlarged view of a surface of a transparent electrode of a solar cell.

As shown in FIG. 1, the solar cell 10 has a structure of a pn junction semiconductor layer composed of a p-type semiconductor layer 15 and an n-type semiconductor layer 17 between electrodes 11 and 13 facing each other. ought.

When a light bulb is connected to the electrodes 11 and 13 of the solar cell 10 as a light emitting unit and the solar cell 10 is exposed to a light source such as sunlight, the n-type semiconductor layer 17 and the p-type semiconductor layer 15 The electromotive force is generated by the photovoltaic effect through which current flows across

As such, a light bulb electrically connected to the solar cell 10 may be turned on by electromotive force generated by the photovoltaic effect.

On the other hand, such a solar cell 10 is transparent to the electrode 11 positioned in the direction toward the light source in order to receive light from the external light source more efficiently into the pn junction semiconductor layers 15 and 17. It is made of material.

Here, the uneven shape of the transparent electrode 11 may be formed by atmospheric chemical vapor deposition (CVD), the uneven shape of the transparent electrode 11 formed through the atmospheric pressure chemical vapor deposition method is shown in FIG. As shown, it is formed into a very sharp pointed mountain shape.

The uneven shape of the transparent electrode 11 is very difficult to control the shape and size of the transparent electrode 11, which has a limit in increasing the optical path.

In addition, some of the light incident into the solar cell is reflected by the back electrode and re-entered into the pn junction semiconductor layer. There is even more light to be emitted.

As a result, the efficiency of the solar cell 10 is lowered.

Therefore, there is a demand for manufacturing a solar cell having higher efficiency.

The present invention is to solve the above problems, it is an object to improve the efficiency of the solar cell.

In order to achieve the above object, the present invention provides an insulating substrate; A first electrode formed on one surface to which light of the insulating substrate is incident; A semiconductor layer formed on the first electrode; A second electrode formed on the semiconductor layer; A lens layer formed on the second electrode, a lens layer formed on one surface of the support layer, and protruding so that a plurality of pyramidal lenses are arranged adjacent to each other in the longitudinal and transverse directions of the support layer; It is formed on the other surface of the formed support layer to provide a neighboring solar cell.

In this case, the thickness of the support layer is 1.06 to 1.1 times the height of the pyramid-shaped lens, the end of the reflective pattern is the light refracted at the vertex of the pyramidal lens and the light refracted at the end of the pyramidal lens It is located at a position corresponding to the point where they meet each other.

The area of the reflective pattern is a height * (1.06 to 1.1) of the pyramidal lens, and includes a reflective pattern formed to correspond to an edge of the pyramidal lens.

Here, the reflective pattern is formed in the shape of a square at the corner of the pyramid-shaped lens or in the shape of a triangle in the corner of the pyramid-shaped lens, the reflection pattern is formed along the edge of the lens of the pyramid-shaped.

In addition, the reflective pattern is made of one selected from silver (Ag), aluminum (Al), silicon oxide (SiO 2), titanium oxide (TiO 2) or magnesium oxide (MgO), the lens layer is a transparent acrylic resin (acryl) resin Or a photosensitive material such as a photoresist.

The support layer is made of one of polymethylmethacrylate (PMMA) or polyethylene terephthalate (PET) and polycarbonate (PC), which are thermoplastic resins. The second electrode is made of a transparent conductive oxide.

The semiconductor layer may include an n-type semiconductor layer, a pure amorphous silicon layer, and a p-type semiconductor layer, and the first electrode may be formed of silver (Ag) or aluminum (Al).

At this time, the surface of the second electrode is uneven.

As described above, according to the present invention, by further forming a microlens layer having a lens layer and a reflective pattern on the second electrode, thereby improving the path of the light incident into the solar cell, thereby capturing light There is an effect that can be increased, there is an effect of improving the efficiency of the solar cell.

Further, the microlens layer of the present invention further forms a reflection pattern at an optimal position, whereby some of the light incident into the solar cell can be recycled to reflect the light reflected by the first electrode. There is an effect of further improving the amount of light.

1 is a schematic diagram illustrating a concept of driving a general solar cell.
Figure 2 is an enlarged view showing the surface of the transparent electrode of the solar cell.
3 is a cross-sectional view schematically showing the structure of a solar cell according to an embodiment of the present invention.
4A-4D are perspective and plan views schematically showing a microlens layer according to an embodiment of the present invention.
5A to 5B are enlarged cross-sectional views of the microlens layer.
6 is a schematic diagram schematically showing the principle that the light efficiency of the solar cell according to an embodiment of the present invention is improved.

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

3 is a cross-sectional view schematically showing the structure of a solar cell according to an embodiment of the present invention.

As shown, the solar cell 100 of the present invention is largely composed of an insulating substrate 101, a semiconductor layer 130 and the first and second electrodes 110, 120, in particular of the second electrode 120 The upper portion is characterized in that the micro-lens layer (200) is located.

In detail, the solar cell 100 defines a transparent insulation substrate 101 and one surface on which light such as sunlight is incident as an upper surface of the insulation substrate 101, and an upper surface of the insulation substrate 101. The first electrode 110, which is called a back electrode, made of silver (Ag) or aluminum (Al) having excellent reflection characteristics is formed.

The semiconductor layer 130 is positioned on the first electrode 110, and the semiconductor layer 130 includes a p-type semiconductor layer 130a including p + -type impurities and an n-type semiconductor layer including n + -type impurities. 130b and a pure amorphous silicon layer 130c positioned between the p-type semiconductor layer 130a and the n-type semiconductor layer 130b.

At this time, electrons in the semiconductor layer 130 should be present asymmetrically. That is, in the semiconductor layer 130, the n-type semiconductor layer 130b has a large electron density and a small hole density, and the p-type semiconductor layer 130a has a small electron density and a large hole density. Have

In addition, a second electrode 120 made of a transparent conductive oxide (TCO) is formed on the semiconductor layer 130 to transmit light such as sunlight.

The second electrode 120 may be made of indium tin oxide (ITO), GaZnO, AlZnO, InZnO, or the like.

In this case, the second electrode 120 may have a concave-convex shape through a texture processing process in order to increase the photovoltaic effect of the solar cell 100. Therefore, it is possible to prevent total reflection at the time of incidence of light and to enlarge light scattering to increase light capture.

Here, the texture processing process is a process of forming a convex convex-convex shape on the surface of the material, which may be performed by an etching process using a photolithography method, an anisotropic etching process using a chemical solution, or a groove forming process using mechanical scribing. Can be.

In addition, the solar cell 100 of the present invention is further provided with a microlens layer 200 on the second electrode 120, the microlens layer 200 is a support layer 210, the upper surface of the support layer 210 The prism layer 220 for changing the path of light incident into the solar cell 100, and the reflective pattern 230 for recycling some light on the lower surface of the support layer 210.

Therefore, in the solar cell 100 of the present invention, a lot of light is incident to the inside, thereby improving the path of the incident light.

Thus, by increasing the light absorption of the solar cell 100 to improve the energy conversion efficiency. As a result, the potential difference in the semiconductor layer 130 becomes greater, thereby improving the efficiency of the solar cell 100. We will discuss this in more detail later.

When the solar cell 100 is exposed to light such as sunlight, electromotive force is generated by a photovoltaic effect in which current flows across the p-type semiconductor layer 130a and the n-type semiconductor layer 130b. do.

The generated electromotive force causes a potential difference between the first electrode 110 and the second electrode 120 to charge the solar cell 100.

At this time, the light incident on the solar cell 100 and passing through the semiconductor layer 130 is reflected by the first electrode 110 and re-entered into the semiconductor layer 130, thereby increasing the electromotive force.

Here, the operation principle of the solar cell 100 will be described in more detail.

As described above, the electrons in the semiconductor layer 130 are asymmetrically present, but in the semiconductor layer 130 formed by the junction of the p-type semiconductor layer 130a and the n-type semiconductor layer 130b in a thermal equilibrium state. Dispersion of charges due to diffusion due to the concentration gradient of carriers results in the formation of an electric field.

Accordingly, light having an energy greater than the band gap energy, which is an energy difference between a conduction band and a valence band of a material forming the semiconductor layer 130, into the semiconductor layer 130. When irradiated, electrons that receive light energy are excited at the conduction band to the conduction band, and the electrons excited at the conduction band can move freely.

In the valence band, holes are generated where electrons escape.

The generated free electrons and holes are called excess carriers, and the excess carriers are diffused by concentration differences in the conduction band or the valence band.

In this case, the excess carriers, that is, electrons excited in the p-type semiconductor layer 130a and holes made in the n-type semiconductor layer 130b are defined as respective minority carriers, and are p-type or n-type before conventional bonding. The carriers (ie, p-type holes and n-type electrons) in the semiconductor layers 130a and 130b are defined as majority carriers.

At this time, the plurality of carriers are interrupted by the flow due to the energy barrier (energy barrier) due to the electric field, electrons that are a minority carrier of the p-type semiconductor layer 130a can move to the n-type semiconductor layer (130b).

Therefore, a potential difference occurs in the semiconductor layer 130 due to the diffusion of the minority carrier, and the first and second electrodes 110 and 120 disposed on both sides of the semiconductor layer 130 are external circuits. By utilizing the electromotive force by connecting to the semiconductor layer 130 is used as a battery.

In this case, when the solar cell 100 of the present invention further forms a microlens layer 200 on the second electrode 120, a lot of light is incident into the solar cell 100 and the path of the incident light is improved. By increasing the light absorption rate of the solar cell 100, the energy conversion efficiency is improved, thereby increasing the potential difference inside the semiconductor layer 130, thereby improving the efficiency of the solar cell 100. It can be.

4A through 4D are schematic perspective and plan views of a microlens layer according to an exemplary embodiment of the present invention.

As shown in FIG. 4A, the microlens layer 200 includes a support layer 210 made of PMMA (polymethylmethacrylate), a thermoplastic resin PET (polyethylene terephthalate), PC (polycarbonate), and the like. 3, the lens layer 220 for changing the path of the light incident into the battery 100 in FIG. 3, and the reflective pattern 230 for recycling some light on the lower surface of the support layer 210. )

Here, the lens layer 220 formed on the upper surface of the support layer 210 is made of a photosensitive material such as a transparent acrylic resin or photoresist, the lens layer 220 is a plurality of pyramid of a micro size The shaped lens 221 protrudes from the support layer 210.

In this case, the plurality of pyramid-shaped lenses 221 are arranged adjacent to each other in the longitudinal direction and the transverse direction of the support layer 210, and closely arranged so that there is no empty space between the adjacent pyramid-shaped lenses 221.

Due to the pyramid-shaped lens 221 to improve the optical path inside the solar cell (100 of FIG. 3).

That is, light such as sunlight is incident vertically into the solar cell (100 of FIG. 3). At this time, the light is refracted at a specific angle due to the pyramid-shaped lens 221 and into the solar cell (100 of FIG. 3). Incident. Therefore, the optical path is improved.

In addition, due to the pyramid-shaped lens 221, the ratio of the sunlight incident on the lens layer 220 to the outside of the solar cell (100 of FIG. 3) is reduced, and with the scattering of the incident sunlight As a result, the rate at which sunlight is absorbed into the solar cell (100 of FIG. 3) is increased.

Accordingly, when light is incident more efficiently, total reflection can be prevented and light scattering can be expanded to increase light capture, thereby improving the efficiency of the solar cell (100 of FIG. 3).

In addition, the microlens layer 200 of the present invention further forms a reflective pattern 230 on the back surface of the support layer 210, so that a part of the light incident into the solar cell 100 of FIG. In the process of being reflected by 110 of 3 and re-incident to the semiconductor layer 130 of FIG. 3, some light passes through the semiconductor layer 130 of FIG. 3 as it is and is emitted to the outside of the solar cell 100 of FIG. 3. Can be prevented.

That is, some of the light reflected by the first electrode 110 of FIG. 3 is re-entered into the semiconductor layer 130 of FIG. 3, and some light passes through the semiconductor layer 130 of FIG. 3 as it is. The light passing through the semiconductor layer 130 (FIG. 3) as it is is reflected by the reflective pattern 230 of the microlens layer 200, and is re-entered into the semiconductor layer 130 (FIG. 3).

Therefore, the amount of light inside the solar cell 100 of FIG. 3 is further improved.

Here, the reflective pattern 232 is made of one of silver (Ag), aluminum (Al), silicon oxide (SiO 2), titanium oxide (TiO 2), or magnesium oxide (MgO).

As shown in FIGS. 4B to 4D, the support layer 210 may be formed on the rear surface of the support layer 210 in various shapes. In this case, as shown in FIG. 4B, the reflective pattern 230 may have a neighboring pyramid shape of the lens layer 220. When formed in the shape corresponding to the pyramid-shaped lens 221 corresponding to the corner of the lens 221, the relative transmittance is very high (99%) compared to the shape of the reflective pattern 230 shown in Figs. 4c and 4d do.

At this time, the reflective pattern 230 is formed along the edge of the pyramid-shaped lens 221, the reflective pattern 230 is formed corresponding to the edge of the adjacent pyramid-shaped lens 221, the shape thereof is pyramidal The relative transmittance of FIG. 4C having a rhombic shape compared to the lens 221 of FIG. 4C is 91%, and the reflective pattern 230 of FIG. 4D having the overall shape of the reflective pattern 230 having a lattice shape has a relative transmittance of 91%.

Here, referring to FIG. 5A, the position and area of the pyramid-shaped lens 221 and the reflective pattern 230 will be described in more detail. As shown in FIG. The parametric lens 221 of the layer 220 is refracted at a specific angle, where the position of the reflective pattern 230 does not interfere with the path of the light refracted by the pyramid-shaped lens 221. It should be formed in.

In more detail, the light incident perpendicularly to the lens layer 220 of the solar cell 100 in FIG. 3 is refracted at a specific angle by the pyramidal lens 221 of the lens layer 220. Snell's law causes the light to refract with a larger angle relative to the normal at the point where light is incident.

In this case, Snell's law is n1sinθ1 = n2sinθ2 ..... (1)

Where n1 and n2 represent refractive indices, θ1 represents an incident angle, and θ2 represents a refractive angle.

That is, light incident on the lens layer 220 at a predetermined angle θ1 is refracted at a predetermined angle θ2 by the pyramid-shaped lens 221 of the lens layer 220.

Using this, the refractive angle θ after passing through the lens layer 220 of incident light with an angle of θa with respect to the pyramidal lens 221 of the lens layer 220 is obtained.

sinθ = n / n'sin (θa-sin ^-1 ((n '/ n) sinθa)) ..... Equation (2)

It may be represented as.

Through the above equation (2), the incident angle θa can be expressed by the following equation.

Θa = 90 °-θb / 2 ..... Equation (3)

Here, θb represents the inclination of the pyramid-shaped lens 221, by changing the angle θb of the pyramid-shaped lens 221 through the above equation (3) to change the incident angle of the light incident on the lens layer 220. In this case, the angle of refraction of the light exiting the lens layer 220 may be adjusted.

At this time, whatever the angle of the pyramid-shaped lens 221, the light incident on the solar cell (100 of FIG. 3) is shown in Figure 5a by the pyramid-shaped lens 221 of the lens layer 220. As shown in FIG. 3, the refractive index is refracted to have a slope corresponding to the area of A.

At this time, the reflective pattern 230 is most within the range that the light refracted from the microlens layer 200 of the solar cell (100 of FIG. 3) does not invade the region where the light is incident toward the second electrode (120 of FIG. 3). It is preferable to form widely.

Therefore, the light reflected by the first electrode 110 in FIG. 3 can be recycled more efficiently.

Here, the reflective pattern 230 may be formed to have an optimal area only when the reflective pattern 230 is formed at an optimal position.

Accordingly, the reflective pattern 230 of the present invention is located at the position B corresponding to the point where the light refracted at the vertex of the pyramidal lens 221 and the light refracted at the end point of the pyramidal lens 221 meet each other. It is best to make sure.

That is, the reflection pattern 230 may be formed to have a larger area as the reflection pattern 230 is located farther from the pyramid-shaped lens 221, the position of the reflection pattern 230 compared to the position of B pyramidal shape When the position of C is further away from the lens 221 of the lens, since the reflective pattern 230 blocks a part of the refracted light, the position of C may be the optimal position where the reflective pattern 230 is to be formed. none.

At this time, the optimal position at which the reflective pattern 230 is formed is preferably located about 1.06 to 1.1 times the height h of the pyramid-shaped lens 221 from the pyramid-shaped lens 221.

That is, in the microlens layer 200 of the present invention, the pyramid-shaped lens 221 of the lens layer 220 protrudes from the support layer 210, and the reflective pattern 230 is formed on the lower surface of the support layer 210. As a result, the distance between the reflective pattern 230 and the pyramid-shaped lens 221 is equal to the thickness d of the support layer 210, so that the thickness d of the support layer 210 is defined as the pyramid-shaped lens 221. It may be about 1.06 to 1.1 times the height (h) can be located in the optimal position where the reflective pattern 230 can have an optimal area.

For example, when the refractive index of the pyramidal lens 221 of the lens layer 220 is 1.56, as shown in FIG. 5B, the vertical light is refracted at an arbitrary point of the pyramidal lens 221. At this time, the light is refracted at an angle of about 18.05 ° from the vertical light.

Accordingly, light refracted by the pyramid-shaped lens 221 passes through the pyramid-shaped lens 221 and the support layer 210.

L = (d + x) * tan18.05 ° .......... Equation (4)

It will reach within the range of.

At this time, the light refracted from the vertex of the pyramidal lens 221 (x = h) is

L1 = (d + h) * tan18.05 ° ........... Equation (5)

The light refracted at the end point of the pyramidal lens 221 (x = 0)

L2 = (d + 0) * tan18.05 ° ............ Equation (6)

It will reach within the range of.

At this time, L1 + L2 = h,

dtan18.05 ° + (d + h) tan18.05 ° = h ............. Equation (7)

Since equation (7) can be redefined as follows.

2dtan18.05 ° = (h h) tan18.05 ° = h (1-tan18.05 °)

∴ d = 2 tan18.05 ° / h (1- tan18.05 °)

= h (1- tan18.05 ° / 2 tan18.05 °) ............. Equation (8)

Equation (8) can be defined as follows again.

d = h * 1.03 ........... Equation (9)

That is, when the height h of the pyramid-shaped lens 221 is 1, the thickness d of the support layer 210 is 1 * 1.03. In this case, the reflective pattern 230 is also formed from the pyramid-shaped lens 221. It is most desirable to be located at 1 * 1.03.

At this time, since the area of the reflective pattern 230 is proportional to the height h of the pyramid-shaped lens 221, it is preferable that the height h of the pyramid-shaped lens * (1.06 to 1.1).

As described above, the solar cell 100 of FIG. 3 further includes a microlens layer 200 provided with a lens layer 220 and a reflection pattern 230 on the second electrode 120. By forming the light, such as sunlight through the lens layer 220 is refracted at a specific angle to be incident into the solar cell (100 of FIG. 3), thereby improving the optical path.

In addition, due to the pyramid-shaped lens 221 of the lens layer 220, the ratio of sunlight incident on the lens layer 220 to the outside of the solar cell (100 of FIG. 3) is reduced, and with Due to scattering of incident sunlight, the rate at which sunlight is absorbed into the solar cell (100 of FIG. 3) is increased.

In addition, the microlens layer 200 of the present invention further forms a reflection pattern 230 at an optimal position of the rear surface of the support layer 210, whereby some of the light incident into the solar cell 100 of FIG. In the process of being reflected by one electrode (110 in FIG. 3) and re-incident to the semiconductor layer (130 in FIG. 3), some light passes through the semiconductor layer (130 in FIG. 3) as it is and the solar cell (100 in FIG. 3). ) Can be prevented from being emitted to the outside.

6 is a schematic view schematically showing a principle that the light efficiency of the solar cell according to the embodiment of the present invention is improved.

As shown, the solar cell 100 of the present invention is increased the rate at which light is absorbed into the solar cell 100 through the micro condensing layer 200.

In addition, the light through the lens layer 220 is refracted at a specific angle to be incident into the solar cell 100, thereby improving the optical path, thereby condensing into the solar cell 100 The incident light is allowed to stay inside the solar cell 100 for a long time.

This is to improve the light trapping ability of the solar cell 100, thereby increasing the amount of light incident on the solar cell 100, thereby improving the light trapping ability, thereby improving the efficiency of the solar cell 100.

In addition, the reflection pattern 230 of the microlens layer 200 prevents the light reflected by the first electrode 110 from being directly emitted to the outside of the solar cell 100 and causes the light to be recycled. The amount of light inside the battery 100 is further improved.

Table 1 below is a result of simulating the absorption rate of light such as sunlight into the semiconductor layer 130 of the solar cell 100 according to an embodiment of the present invention.

Sample 1 Sample 2 Sample 3 Light absorption of semiconductor layer 100% 110% 165%

In Table 1 above, sample 1 is a simulation result of a general solar cell, and sample 2 is a simulation result of a solar cell including a transparent electrode whose surface is formed in an irregular shape through a texture processing process, and sample 3 is the present invention. Simulation results of a solar cell provided with a microlens layer according to an embodiment of the present invention.

Here, it can be seen that the light absorption of the semiconductor layer is improved by about 10% compared to the general solar cell through the texture processing process, but the absorption rate of the semiconductor layer of the solar cell according to the embodiment of the present invention is 165%, It can be seen that the absorption of light is improved by about 65% or more.

As described above, the solar cell 100 of the present invention further forms a microlens layer 200 having the lens layer 220 and the reflection pattern 230 on the second electrode 120, thereby providing a solar cell ( 100) to improve the path of the light incident to the inside, it is possible to increase the light capture, thereby improving the efficiency of the solar cell (100).

In addition, the microlens layer 200 of the present invention further forms a reflective pattern 230 at an optimal position of the back surface of the support layer 210, so that a part of the light incident into the solar cell 100 is transferred to the first electrode ( The light reflected by 110 may be recycled, thereby further improving the amount of light inside the solar cell 100.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

100: solar cell, 101: insulating substrate
110: first electrode
120: second electrode
130: semiconductor layer (130a: p-type semiconductor layer, 130b: n-type semiconductor layer, 130c: pure amorphous silicon layer)
200: microlens layer (210: support layer, 220: lens layer, 221: pyramidal lens, 230: reflection pattern)

Claims

An insulating substrate;
A first electrode formed on one surface to which light of the insulating substrate is incident;
A semiconductor layer formed on the first electrode;
A second electrode formed on the semiconductor layer;
A lens layer formed on the second electrode, a lens layer formed on one surface of the support layer, and protruding so that a plurality of pyramidal lenses are arranged adjacent to each other in the longitudinal and transverse directions of the support layer; Solar cells formed on the other surface of the support layer formed and neighboring.

The method of claim 1,
The support layer has a thickness of 1.06 to 1.1 times the height of the pyramid-shaped lens.

The method of claim 1,
One end of the reflective pattern is located at a position corresponding to the point where the light refracted at the vertex of the pyramid-shaped lens and the light refracted at the end of the pyramid-shaped lens meet each other.

The method of claim 1,
The area of the reflective pattern is the height * (1.06 ~ 1.1) of the pyramidal lens.

The method of claim 1,
Solar cell comprising a reflective pattern formed corresponding to the edge of the pyramid-shaped lens.

The method of claim 5, wherein
The reflective pattern is formed in a rectangular shape on the corner of the pyramid-shaped lens, or a solar cell formed in a triangular shape on the corner of the pyramid-shaped lens.

The method of claim 1,
The reflective pattern is formed along the edge of the pyramidal lens.

The method of claim 1,
The reflective pattern is a solar cell comprising one selected from silver (Ag), aluminum (Al), silicon oxide (SiO 2), titanium oxide (TiO 2) or magnesium oxide (MgO).

The method of claim 1,
The lens layer is a solar cell comprising one selected from photosensitive materials such as transparent acrylic (acryl) resin or photoresist (photoresist).

The method of claim 1,
The support layer is a solar cell consisting of one of polymethylmethacrylate (PMMA) or polyethylene terephthalate (PET) and polycarbonate (PC).

The method of claim 1,
The second electrode is a solar cell made of a transparent conductive oxide (transparent conductive oxide).

The method of claim 1,
The semiconductor layer is a solar cell consisting of an n-type semiconductor layer, a pure amorphous silicon layer and a p-type semiconductor layer.

The method of claim 1,
The first electrode is a solar cell consisting of one selected from silver (Ag) or aluminum (Al).

The method of claim 1,
The second electrode has a concave-convex surface.