KR20100022622A - System of manufacturing solar cell - Google Patents

Abstract

PURPOSE: A system of manufacturing a solar cell is provided to improve a processing efficiency of a thin film deposition by forming a thin film deposition unit as a cluster structure. CONSTITUTION: A manufacturing sytem of a solar cell system comprises a first electrode-forming portion(110), a first patterning part(120), a thin film deposition part(200), a second patterning part(140), a second electrode-forming portion(150), and a third patterning part(160). The first electrode-forming portion has a first conductive layer on the substrate(310). The first patterning part have the electrode which is formed by pattering first conductive layer. A thin film deposition unit deposits a photoelectric transformation layer on the substrate by using a processing chamber. The processing chamber comprises a multi-channel electrode assembly. The multi-channel electrode assembly comprises a plurality of constant voltage electrodes and plurality of negative voltage electrodes. A plurality of constant voltage electrodes and plurality of negative voltage electrodes generates plasma.

Description

Solar cell manufacturing system {SYSTEM OF MANUFACTURING SOLAR CELL}

The present invention relates to a solar cell manufacturing system, and more particularly to a solar cell manufacturing system for the production of thin-film solar cells that produce power using sunlight.

In general, a solar cell is a device that converts solar energy into electrical energy, and is an alternative energy source that can replace energy sources such as coal and oil due to various advantages such as environment-friendly, long-lasting, and infinite energy source. As such, the field of application continues to expand.

Solar cells can be broadly classified into silicon-based, compound-based, and organic-based, depending on the materials used, of which silicon-based solar cells currently occupy most of them.

Silicon-based solar cells may be further classified into crystalline solar cells made of monocrystalline or polycrystalline silicon and thin film solar cells made of amorphous or microcrystalline silicon. However, the crystalline solar cell has a disadvantage in that the manufacturing cost is increased while the photoelectric efficiency is high, and the thin film solar cell has a disadvantage in that the photoelectric efficiency is lower than that of the crystalline form while the manufacturing cost is low. Accordingly, in recent years, research into the manufacturing technology of the thin-film solar cell that can improve the photoelectric efficiency is in progress, and at the same time, the development of a manufacturing system that can improve the productivity of solar cell manufacturing is required.

Accordingly, the present invention has been made in view of such a need, and the present invention provides a solar cell manufacturing system capable of improving the process efficiency and productivity of solar cell manufacturing.

A solar cell manufacturing system according to an aspect of the present invention includes a first electrode forming unit, a first patterning unit, a thin film deposition unit, a second patterning unit, a second electrode forming unit, and a third patterning unit. The first electrode forming part forms a first conductive layer on a substrate. The first patterning part patterns the first conductive layer to form a first electrode. The thin film deposition unit deposits a photoelectric conversion layer on a substrate on which the first electrode is formed using at least one process chamber including a split electrode assembly including a plurality of constant voltage electrodes and a plurality of negative voltage electrodes for generating a plasma. do. The second patterning part patterns the photoelectric conversion layer to form a photoelectric conversion part. The second electrode forming part forms a second conductive layer on the substrate on which the photoelectric conversion part is formed. The third patterning part patterns the second conductive layer to form a second electrode.

The constant voltage electrodes and the negative voltage electrodes may be formed of an alternating linear arrangement, a matrix arrangement, an alternate spiral arrangement, an alternating concentric arrangement, and the like.

The thin film deposition unit may include a central chamber including a substrate transfer unit for transferring a substrate, a first process chamber for depositing a first impurity doped silicon layer on a substrate transferred by the substrate transfer unit, and the first impurity doped silicon. One or more second process chambers for depositing an intrinsic silicon layer on the layered substrate and a third process chamber for depositing a second impurity doped silicon layer on the substrate on which the intrinsic silicon layer is formed.

At least one of the first process chamber, the second process chamber, and the third process chamber may further include a laser supply unit supplying a laser into the chamber body to increase the plasma density. The laser supply unit includes one or more laser generators installed outside the chamber body to supply a laser into the chamber body. The laser supply unit may further include one or more reflecting members reflecting the laser output from the laser generator to form a plurality of laser scanning lines in the chamber body.

At least one of the first process chamber, the second process chamber, and the third process chamber may further include a remote plasma generator installed outside the chamber body to supply plasma to the inside of the chamber body.

The second process chamber alternately deposits a plurality of amorphous silicon layers and a plurality of microcrystalline silicon layers to form the intrinsic silicon layer. For example, the second process chamber may alternately deposit the amorphous silicon layer and the microcrystalline silicon layer by changing the frequency of the radio frequency power supplied to the split electrode assembly.

The first impurity doped silicon layer may be formed of a p-type silicon layer including p-type impurities, and the second impurity doped silicon layer may be formed of an n-type silicon layer including n-type impurities. In addition, the first conductive layer may be formed of a transparent conductive material, and the second conductive layer may be formed of a conductive light reflecting material.

In a solar cell manufacturing system, a transfer device for sequentially transferring a substrate to the first electrode forming unit, the first patterning unit, the thin film deposition unit, the second patterning unit, the second electrode forming unit, and the third patterning unit. It further includes.

The first patterning unit, the second patterning unit, and the third patterning unit may include a laser supplier for supplying a laser for patterning a thin film. For example, the laser supplier may be installed at a lower portion of the transfer device to supply a laser to a substrate passing over the transfer device.

The solar cell manufacturing system may further include a cleaning unit installed at the front end of the first electrode forming unit and cleaning the surface of the substrate. The solar cell manufacturing system may further include a texturing unit configured to receive the substrate on which the first conductive layer is formed and to texturize the first conductive layer.

According to such a solar cell manufacturing system, by connecting in-line several devices for manufacturing a solar cell, it is possible to improve the process efficiency and reduce the manufacturing cost. In addition, by forming the thin film deposition unit for forming the silicon thin film in a cluster structure having a plurality of process chambers, it is possible to increase the process efficiency of the thin film deposition. Furthermore, by using the process chamber of the split-electrode structure, it is possible to easily deposit an intrinsic silicon layer in which amorphous silicon layers and microcrystalline silicon layers are alternately stacked, thereby manufacturing a solar cell having improved photoelectric efficiency. have.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The above-described features and effects of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, and thus, those skilled in the art to which the present invention pertains may easily implement the technical idea of the present invention. Could be. The present invention is not limited to the following embodiments and may be implemented in other forms. The embodiments introduced herein are provided to make the disclosure more complete and to fully convey the spirit and features of the present invention to those skilled in the art. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. In the drawings, the thickness of each device or film (layer) and regions has been exaggerated for clarity of the invention, and each device may have various additional devices not described herein.

1 is a configuration diagram schematically showing a solar cell manufacturing system according to an embodiment of the present invention.

Referring to FIG. 1, the solar cell manufacturing system 100 includes a first electrode forming unit 110, a first patterning unit 120, a thin film deposition unit 200, a second patterning unit 140, and a second electrode formation. The unit 150 and the third patterning unit 160 are included. In addition, the solar cell manufacturing system 100 may further include a transfer device 170 for transferring the substrate 310.

Each component of the solar cell manufacturing system 100 described above may be implemented as a separate device and connected to each other through the transfer device 170. The transfer device 170 may include a substrate 310 for manufacturing a solar cell, including a first electrode forming unit 110, a first patterning unit 120, a thin film deposition unit 130, a second patterning unit 140, and a first electrode forming unit 110. The electrode is sequentially transferred to the second electrode forming unit 150 and the third patterning unit 160. The transfer device 170 may include a conveyor belt or a robot arm for transferring the substrate 310. In addition, the transfer apparatus 170 may include various means for transferring the substrate 310.

Hereinafter, components of the solar cell manufacturing system will be described in detail in connection with the manufacturing process of the solar cell.

2 to 4 and 15 to 17 are schematic cross-sectional views showing the manufacturing process of the solar cell according to an embodiment of the present invention for each process step.

1 and 2, the substrate 310 loaded in the transfer apparatus 170 is transferred to the first electrode forming unit 110 through the transfer of the transfer apparatus 170. The substrate 310 may be formed of transparent glass or plastic so that light can pass therethrough. Preferably, the substrate 310 may be formed of soda-lime glass to which boron is added.

In the first electrode forming unit 110, a first conductive layer 320 is formed on the substrate 310 transferred through the transfer device 170. The first electrode forming unit 110 forms the first conductive layer 320 through, for example, a sputtering method or a low pressure chemical vapor deposition (LPCVD) method.

The first conductive layer 320 is formed of a transparent conductive material so that light incident from the substrate 310 side can be transmitted. For example, the first conductive layer 320 may be formed of tin oxide, zinc oxide, indium tin oxide, indium zinc oxide, or the like. On the contrary, when the direction in which light is incident is opposite, the first conductive layer 320 may be formed of a conductive light reflecting material for reflecting light. Meanwhile, when the substrate 310 having the first conductive layer 320 deposited thereon is introduced into the solar cell manufacturing system 100, the first electrode forming unit 110 may be removed.

1 and 3, the substrate 310 on which the first conductive layer 320 is formed in the first electrode formation unit 110 is transferred to the first patterning unit 120 through the transfer device 170. The first patterning unit 120 patterns the first conductive layer 320 to form a first electrode 322.

The first patterning unit 120 includes a laser supplier 122 that supplies a laser for patterning the first conductive layer 320. When patterning is performed through a laser, particles generated during patterning may be accumulated on the substrate 310 to cause a defect such as a short circuit. Therefore, the laser supplier 122 is installed below the transfer device 170 so that particles generated during the patterning of the first conductive layer 320 do not accumulate on the substrate 310 and pass through the upper portion of the transfer device 170. It is preferable to supply a laser to 310. To this end, the operation of overturning the substrate 310 on which the first conductive layer 320 is formed in the first electrode forming unit 110 before reaching the first patterning unit 120 must be performed. On the other hand, the laser supplier 122 may be installed on the upper portion of the transfer device 170, in this case it is not necessary to turn over the substrate 310. When the laser supplier 122 is installed on the upper portion of the transfer device 170, an additional cleaning unit (not shown) is added to the rear end of the first patterning unit 120 to remove particles generated during patterning, and the cleaning operation is performed. It is desirable to.

1 and 4, the substrate 310 on which the first electrode 322 is formed in the first patterning unit 120 is transferred to the thin film deposition unit 200 through the transfer device 170. The thin film deposition unit 200 deposits the photoelectric conversion layer 330 on the substrate 310 on which the first electrode 322 is formed.

FIG. 5 is a perspective view illustrating in detail the thin film deposition unit illustrated in FIG. 1, FIG. 6 is a plan view illustrating the thin film deposition unit illustrated in FIG. 5, and FIG. 7 is a plan view schematically illustrating the interior of the central chamber illustrated in FIG. 5.

4 to 7, the thin film deposition unit 200 may include a central chamber 210, a first process chamber 220, a second process chamber 230, and a third process chamber 240. .

The thin film deposition unit 200 may be formed of a centralized multi-chamber structure, that is, a cluster structure, and the central chamber 210 is installed at the center of the cluster structure. The central chamber 210 may have a quadrangular, five, six, or more polygonal structure according to the number of process chambers installed in the periphery. For example, in FIG. 5, the central chamber 210 having an octagonal structure is illustrated. ) Is illustrated.

The central chamber 210 includes a substrate transfer unit 212 for transferring the substrate 310. The substrate transfer unit 212 draws the substrate 310 from the loading / unloading unit 250 to transfer the substrate 310 to each process chamber, or withdraws the substrate 310 from each process chamber to load / unload the substrate 310. The substrate 310 is transferred to the unit 250. For the transfer of the substrate 310, the substrate transfer unit 212 may include a blade 214 for supporting the substrate 310, an arm 216 for transferring the substrate 310, and the like. In addition, the substrate transfer unit 212 may be configured by various means capable of transferring the substrate 310.

The substrate 310 loaded in the loading / unloading unit 250 is transferred to the first process chamber 220 through the substrate transfer unit 212. The first process chamber 220 deposits a first impurity doped silicon layer 332 on the substrate 310 on which the first electrode 322 is formed.

The substrate 310 in which the first impurity doped silicon layer 332 is formed in the first process chamber 220 is transferred to the second process chamber 230 through the substrate transfer unit 212. The second process chamber 230 deposits the intrinsic silicon layer 334 on the substrate 310 on which the first impurity doped silicon layer 332 is formed.

The substrate 310 on which the intrinsic silicon layer 334 is formed in the second process chamber 230 is transferred to the third process chamber 240 through the substrate transfer unit 212. The third process chamber 240 deposits a second impurity doped silicon layer 336 on the substrate 310 on which the intrinsic silicon layer 334 is formed.

Meanwhile, since the deposition rate of the intrinsic silicon layer 334 may be slower than the deposition rates of the first impurity doped silicon layer 332 and the second impurity doped silicon layer 336, the second process may be performed for smooth flow or flow. The chamber 230 may have a larger number than the first process chamber 220 and the third process chamber 240. For example, FIG. 5 illustrates a configuration in which five second process chambers 230 are installed. Meanwhile, the arrangement positions of the first, second and third process chambers 220, 230, and 240 may be variously changed.

As it passes through the first process chamber 220, the second process chamber 230, and the third process chamber 240, the first impurity doped silicon layer 332, the intrinsic silicon layer 334, and the substrate 310 are disposed on the substrate 310. Formation of the photoelectric conversion layer 330 including the second impurity doped silicon layer 336 is completed. For example, the first impurity doped silicon layer 332 is formed of a silicon material including p-type impurities such as trivalent elements such as boron (B) and potassium (K), and the second impurity doped silicon layer 336. Silver may be formed of a silicon material including n-type impurities such as phosphorus (P), arsenic (As), and antimony (Sb). Hereinafter, for convenience of description, the first impurity doped silicon layer 332 is referred to as a p-type silicon layer, and the second impurity doped silicon layer 336 is referred to as an n-type silicon layer. Accordingly, the photoelectric conversion layer 330 is formed of a fin (PIN) diode structure in which the p-type silicon layer 332, the intrinsic silicon layer 334, and the n-type silicon layer 336 are sequentially stacked, and light incident from the outside is formed. In response to the photoelectric effect. On the other hand, since the p-type silicon layer should be disposed on the side where the light is incident, the positions of the p-type silicon layer 332 and the n-type silicon layer 336 may be changed depending on the direction of light incidence.

The p-type silicon layer 332 may be formed to include at least one of amorphous silicon and micro-crystalline silicon. For example, the p-type silicon layer 332 may include a structure in which amorphous silicon is doped with p-type impurities, a structure in which microcrystalline silicon is doped with p-type impurities, or amorphous silicon and microcrystalline silicon doped with p-type impurities. It may be formed in a stacked structure and the like.

Light incident from the outside through the substrate 310 passes through the p-type silicon layer 332 and reaches the intrinsic silicon layer 334 which substantially causes photoelectric conversion. Therefore, in order to prevent loss of light incident on the intrinsic silicon layer 334, it is preferable that the light passing through the p-type silicon layer 332 is passed through the p-type silicon layer 332 without being absorbed. For this purpose, the p-type silicon layer 332 preferably has a band gap characteristic different from that of the intrinsic silicon layer 332, and in particular, the p-type silicon layer 332 may be intrinsic silicon so that light is not absorbed. It is desirable to have a large bandgap energy as compared to layer 332. In order to increase the band gap energy, carbon (C) may be further added to the p-type silicon layer 332. The p-type silicon layer 332 may be formed to a thickness of, for example, about 200 to about 1000 mm 3.

The n-type silicon layer 336 may be formed of a silicon material doped with n-type impurities such as phosphorus (P), arsenic (As), and antimony (Sb). The n-type silicon layer 336 may be formed to include at least one of amorphous silicon and microcrystalline silicon. For example, the n-type silicon layer 336 may have a structure in which amorphous silicon is doped with n-type impurities, a structure in which microcrystalline silicon is doped with n-type impurities, or amorphous silicon and microcrystalline silicon doped with n-type impurities. It may be formed in a structure such as. For example, the n-type silicon layer 336 may be formed to a thickness of about 200 to 1000 micrometers.

FIG. 8 is a cross-sectional view illustrating an embodiment of the intrinsic silicon layer illustrated in FIG. 4.

Referring to FIG. 8, the second process chamber 230 alternately deposits a plurality of amorphous silicon layers 337 and a plurality of microcrystalline silicon layers 338 to form an intrinsic silicon layer 334. can do. Here, the microcrystalline silicon layer 338 refers to a layer in which nanoscale silicon crystals having a crystal size of several tens of nm to several hundred nm are formed as a boundary material between amorphous and single crystal silicon. 8 illustrates a structure in which two amorphous silicon layers 337 and two microcrystalline silicon layers 338 are alternately stacked, but in practice, a larger number of amorphous silicon layers 337 and microcrystalline layers are shown. Silicon layers 338 may be formed. The amorphous silicon layer 337 and the microcrystalline silicon layer 338 may have different thicknesses or may be formed to have the same thickness. In addition, the amorphous silicon layers 337 and the microcrystalline silicon layers 338 may be formed to have the same number of layers or different numbers of layers. The thickness of the intrinsic silicon layer 334 may be elastically changed according to the thickness ratio of the amorphous silicon layer 337 and the microcrystalline silicon layer 338, and may be, for example, formed to a thickness of about 500 nm to 2000 nm.

In general, in the photoelectric device using the silicon thin film, the photoelectric efficiency is determined according to the light absorption rate and the photoelectric conversion efficiency of the intrinsic silicon layer 334. From this point of view, the amorphous silicon layer 337 does not have a crystal plane, so the light absorption rate is superior to that of the microcrystalline silicon layer 338. On the other hand, since the microcrystalline silicon layer 338 reflects light at the crystal plane, the light absorption rate is lower than that of the amorphous silicon layer 337, but the electron absorption is superior to the amorphous silicon layer 337. The photoelectric conversion efficiency for conversion is superior to that of the amorphous silicon layer 337. Therefore, when the amorphous silicon layers 337 having excellent light absorptivity and the microcrystalline silicon layers 338 having excellent photoelectric conversion efficiency are alternately formed, both the light absorbance and the electron mobility are excellent at the portions where the two layers meet. The region may be formed to improve the photoelectric efficiency of the intrinsic silicon layer 334. In addition, since the amorphous silicon layer 337 and the microcrystalline silicon layer 338 absorb light of different wavelength bands, the microcrystalline silicon layer 338 absorbs light of the wavelength band not absorbed by the amorphous silicon layer 337. The photoelectric efficiency can be improved.

Meanwhile, the light absorption rate varies depending on the thicknesses of the amorphous silicon layers 337 formed on the intrinsic silicon layer 334. According to Lambert's law, the logarithm of the ratio between the intensity of light incident on the absorbing layer and the intensity of transmitted light is proportional to the thickness of the absorbing layer. Accordingly, when the thickness of the amorphous silicon layer is about 0.3 μm or more, the light absorption is 90% or more, and particularly, when the thickness of the amorphous silicon layer is about 0.4 μm or more, the light absorption is 95% or more. In addition, when the thickness of the amorphous silicon layer is 1.0 mu m, it has a light absorption of almost 100%. In consideration of the characteristics of the amorphous silicon layer, the total thickness of the amorphous silicon layers 337 formed on the intrinsic silicon layer 334 is preferably about 0.4 to 1.0 μm.

As such, when the plurality of amorphous silicon layers 337 and the plurality of microcrystalline silicon layers 338 are alternately formed in the intrinsic silicon layer 334, absorption and reflection of incident light may be repeatedly performed in the various silicon layers. As a result, the photoelectric efficiency is increased compared to a structure using only an amorphous silicon layer or a microcrystalline silicon layer. Meanwhile, the p-type silicon layer 332, the intrinsic silicon layer 334, and the n-type silicon layer 336 may be continuously deposited in one process chamber.

FIG. 9 is a view schematically illustrating a second process chamber according to an embodiment of the present invention, and FIG. 10 is a perspective view illustrating the split electrode assembly illustrated in FIG. 9.

9 and 10, the second process chamber 230 includes a chamber body 410 and a split electrode assembly 430 for generating plasma in the chamber body 410.

The split electrode assembly 430 is installed to face the substrate support 440 supporting the substrate 310. The split electrode assembly 430 includes a plurality of constant voltage electrodes 432 and a plurality of negative voltage electrodes 434 for generating a plasma in the chamber body 410. The constant voltage electrodes 432 and the negative voltage electrodes 434 may be installed in a linear arrangement structure alternately arranged at regular intervals. In addition, the constant voltage electrodes 432 and the negative voltage electrodes 434 may have various arrangement structures such as an array structure of a matrix form, an alternate spiral arrangement structure, and an alternate concentric circle arrangement structure.

The second process chamber 230 may further include a main power supply 450 for applying power to the constant voltage electrodes 432 and the negative voltage electrodes 434. The radio frequency power generated by the main power supply 450 may be supplied to the constant voltage electrodes 432 and the negative voltage electrodes 434 through the impedance matcher 452 and the distribution circuit 454. The distribution circuit 454 supplies the radio frequency power provided from the main power supply 450 to the constant voltage electrodes 432 and the plurality of divided constant voltage electrodes 432 and the negative voltage electrodes 434 to be driven in parallel. The negative voltage electrodes 434 are distributed and supplied. Preferably, the distribution circuit 454 is configured as a current balancing circuit to control the currents supplied to the constant voltage electrodes 432 and the negative voltage electrodes 434 to automatically balance each other. The constant voltage output from the distribution circuit 454 is supplied to the constant voltage electrode 432, and a negative voltage having a phase different from that of the constant voltage is supplied to the negative voltage electrode 434. Alternatively, the constant voltage output from the distribution circuit 454 is supplied to the constant voltage electrodes 432, while the negative voltage electrodes 434 can be commonly grounded. Therefore, plasma is generated between the constant voltage electrode 432 and the negative voltage electrode 434 by the radio frequency power supplied from the main power supply 450.

The constant voltage electrodes 432 and the negative voltage electrodes 434 may be mounted on the electrode mounting plate 436. The electrode mounting plate 436 may be formed of a metal, a nonmetal, or a mixed material thereof. When the electrode mounting plate 436 is formed of metal, a structure electrically insulated from the constant voltage electrodes 432 and the negative voltage electrodes 434 should be applied. A plurality of gas injection holes 438 may be formed in the electrode mounting plate 436. The gas injection holes 438 may be formed in various shapes such as circles, ellipses, squares, triangles, polygons, and the like. The gas injection holes 438 may be formed at regular intervals along the length direction between the constant voltage electrode 432 and the negative voltage electrode 434. In contrast, the gas injection hole 438 may be formed in a slit shape extending in the longitudinal direction between the constant voltage electrode 432 and the negative voltage electrode 434.

The gas supply assembly 420 may be installed outside the split electrode assembly 430. The gas supply assembly 420 may include a gas inlet 422 connected to an external gas supply 460, one or more gas distribution plates 424, and a plurality of gas inlets 426. In this case, the gas injection holes 426 are formed to correspond to the gas injection holes 438 formed in the electrode mounting plate 436. Accordingly, the reaction gas input from the gas supply unit 460 through the gas inlet 422 is evenly distributed by the one or more gas distribution plates 424, and the gas injection holes 426 and the corresponding gas injection holes 438. It may be evenly injected into the chamber body 410 through).

The substrate support 440 may be biased by the bias power supply 442 to increase the plasma generation efficiency. For example, the radio frequency power output from the bias power supply 442 is biased to the substrate support 440 via the impedance matcher 444. Meanwhile, the substrate support 440 may have a dual bias structure in which different radio frequency power sources are biased from two bias power supplies. In addition, the substrate support 440 may be connected to ground and maintained at zero potential without supply of bias. The substrate support 440 may include a heater (not shown) for heating the substrate 310.

On the other hand, the substrate support 440 may have a structure capable of linear or rotational movement in parallel with the substrate 310 under the control of the movement control unit 460 to increase the process efficiency. In contrast, the substrate support 440 may have a structure fixed inside the chamber body 410.

9 illustrates a structure in which the substrate support 440 is installed in the lower region of the chamber body 410 and the split electrode assembly 430 is installed in the upper region of the chamber body 410. ) May be installed at the top and the split electrode assembly 430 may be installed at the bottom.

According to the second process chamber 230 having the above structure, the electrodes for plasma discharge may have a split electrode structure in which a plurality of constant voltage electrodes 432 and a plurality of negative voltage electrodes 434 are alternately arranged at regular intervals. By forming the same, it is possible to generate a uniform plasma over a large area, and to automatically balance the current in parallel driving of the constant voltage electrodes 432 and the negative voltage electrodes 434, thereby making the plasma of the large area more uniform. Can be generated and maintained.

On the other hand, the second process chamber 230 is installed between the gas supply unit 460 and the chamber body 410, a remote plasma generator (RPG, 480) for supplying a plasma inside the chamber body 410 It may further include. The remote plasma generator 480 generates plasma by applying high frequency power to the reaction gas supplied from the gas supply unit 450. The plasma generated by the remote plasma generator 480 may be supplied to the chamber body 410 through the gas supply assembly 420.

FIG. 11 is a view schematically showing a second process chamber according to another embodiment of the present invention, and FIGS. 12 to 14 are views showing various configuration methods of the laser supply unit shown in FIG. 11. In FIG. 11, the rest of the configuration except that the laser supply unit is added is the same as that shown in FIG. 9, and the same reference numerals are used for the same components, and detailed description thereof will be omitted.

11 to 14, the second process chamber 500 further includes a laser supply unit 510 for supplying a laser into the chamber body 410 to increase the plasma density.

The laser supply unit 510 is installed outside the chamber body 410. When the laser supply unit 510 is installed inside the chamber body 410, the deposition material deposited on the substrate 310 may be unnecessarily deposited on the laser supply unit 510, thereby lowering the function of the laser supply unit 510. In order to prevent contamination of the laser supply unit 510, the laser supply unit 510 may be installed outside the chamber body 410.

The laser supply unit 510 supplies a laser into the chamber body 410 such that the laser scan line 512 is formed in a region between the constant voltage electrode 432 and the negative voltage electrode 434 where the plasma is generated. The laser supplied from the laser supply unit 510 excites the reaction gas introduced into the chamber body 410 to further generate plasma. Therefore, the plasma generation by the laser is added between the constant voltage electrode 432 and the negative voltage electrode 434 together with the plasma generation by the constant voltage electrode 432 and the negative voltage electrode 434, thereby increasing the density of the plasma. . Meanwhile, since the plasma formed inside the chamber body 410 may include various kinds of ionized particles according to the reactant gas supplied, the wavelength of the laser generated from the laser supply unit 510 corresponding to the particles included in the plasma. By changing, the density of the plasma can be further increased.

Since the laser supply 510 is installed outside the chamber body 410, the chamber body 410 may include one or more laser transmission windows 412 for transmitting the laser from the laser supply 510 into the chamber body 410. ) May be included. For example, the laser transmission window 412 may be formed in a slot shape on the side facing each other of the chamber body 410, or may be formed in a band shape surrounding the side. In addition, the laser transmission window 412 may be formed in various forms according to the arrangement of the laser supply unit 510.

The laser supply 510 includes one or more laser generators 514 installed outside the laser transmission window 412 to scan the laser into the chamber body 410. The laser generator 514 scans the laser into the chamber body 410 through the laser transmission window 412 to form at least one laser scan line 512 inside the chamber body 410.

Referring to FIG. 12, the laser supply unit 510 includes a plurality of laser generators 514 arranged at one side of the chamber body 410 along the laser transmission window 412, and at the other side of the chamber body 410. The laser terminations 516 may have a structure arranged along the laser transmission window 412. Therefore, as many laser scan lines 512 are formed as the number of laser generators 514 installed.

Referring to FIG. 13, the laser supply unit 510 reflects a laser output from the laser generator 514 to form one or more reflective members 518 in the chamber body 410 to form a plurality of laser scan lines 512. ) May be further included. The laser supply 510 may be composed of a plurality of laser generators 514, a plurality of reflective members 518, and a plurality of laser terminations 516. That is, the laser supply unit 510 may have a structure in which a plurality of laser generators 514 are spaced apart from each other, and a plurality of reflective members 518 are installed on the opposite side of the laser generator 514. Therefore, the laser generated by the laser generator 514 is reflected through the reflective member 518 installed on the opposite side to form a plurality of laser scan lines 512 while reciprocating the inside of the chamber body 410.

Referring to FIG. 14, the laser supply unit 510 includes a single laser generator 514 and a plurality of reflective members 518 reflecting the laser generated by the laser generator 514 to reciprocate inside the chamber body 410. And one laser terminator 516 to form a plurality of laser scan lines 512 in the chamber body 410.

Meanwhile, in addition to the structure illustrated in FIGS. 12 to 14, the laser supply unit 510 may have various structures for forming a plurality of laser scan lines 512 inside the chamber body 410. In addition, an optical system of a suitable structure may be used to scan the laser from the laser generator 514 into the chamber body 410.

As such, by forming a plurality of laser scanning lines 512 inside the chamber body 410 through the laser supply unit 510 installed outside the chamber body 410, the density of the plasma may be improved. Through the deposition rate of the thin film formed on the substrate 310 can be increased.

Meanwhile, the first process chamber 220 for forming the p-type silicon layer 332 and the third process chamber 240 for forming the n-type silicon layer 336 may be formed for forming the intrinsic silicon layer 334. Since it may have a structure substantially the same as the second process chamber 230, a detailed description thereof will be omitted.

The physical properties of the thin film deposited in the process chamber change depending on the reactant gas supplied. Accordingly, silane (SiH 4), hydrogen (H 2) and diborane (B 2 H 6) gases may be supplied to the first process chamber 220 to form the p-type silicon layer 332, and the second process chamber 230 may be used. ) May be supplied with silane (SiH4) and hydrogen (H2) gases to form the intrinsic silicon layer 334, and silane (SiH4) to form the n-type silicon layer 336 in the third process chamber 240. ), Hydrogen (H2) and phosphine (PH3) gases can be supplied. In addition, when depositing the p-type silicon layer 332, methane (CH4) gas may be added to the first process chamber 220 to increase the band gap energy. In addition, when the microcrystalline silicon layer 338 is deposited on the second process chamber 230, silicon fluoride (SiF 4) gas may be added to prevent the formation of the amorphous silicon layer.

In forming the silicon thin film in the first to third process chambers 220, 230, and 240, the dilution ratio of hydrogen (H 2), the power and frequency of the radio frequency power applied to the electrode, the temperature and pressure of the chamber The properties of the silicon thin film to be formed vary depending on such conditions. Therefore, the amorphous silicon layer 337 or the microcrystalline silicon layer 338 may be formed by controlling process conditions of the first to third process chambers 220, 230, and 240 for forming the silicon thin film. In particular, when the second process chamber 230 having the split electrode structure is used, the amorphous silicon layer 337 and the microcrystalline silicon layer 338 are changed by only changing the frequencies of the radio frequency power supplied to the split electrode assembly 430. Can be formed alternately. For example, when the radio frequency power having a frequency of about 2 to 13.56 MHz is supplied to the split electrode assembly 430, an amorphous silicon layer 337 is deposited, and the radio frequency power having about 40 to 100 MHz is divided into the split electrode assembly 430. ), The microcrystalline silicon layer 338 is deposited. As such, by changing only the frequency of the radio frequency power supply to the split electrode assembly 430, the amorphous silicon layer 337 and the microcrystalline silicon layer 338 can be alternately deposited simply without changing other process conditions. .

On the other hand, since the time for forming the light crystal conversion layer 330 in the thin film deposition unit 200 may take more time than the time for forming the first conductive layer 320 in the first electrode forming unit 110, A plurality of thin film deposition units 200 may be provided to smooth the flow and shorten the manufacturing time.

1 and 15, the substrate 310 in which the deposition of the photoelectric conversion layer 330 is completed in the thin film deposition unit 200 is transferred to the second patterning unit 140 through the transfer device 170. The second patterning unit 140 patterns the photoelectric conversion layer 330 to form the photoelectric conversion unit 340. The photoelectric conversion unit 340 includes a p-type silicon part 342, an intrinsic silicon part 344, and an n-type silicon part 346.

The second patterning unit 140 includes a laser supplier 142 that supplies a laser for patterning the photoelectric conversion layer 330. Since the laser supplier 142 included in the second patterning unit 140 has substantially the same configuration as the laser supplier 122 included in the first patterning unit 120, a detailed description thereof will be omitted.

1 and 16, the substrate 310 on which the photoelectric conversion unit 340 is formed while passing through the second patterning unit 150 is transferred to the second electrode forming unit 150 through the transfer device 170. Transferred. The second electrode forming unit 150 forms a second conductive layer 350 on the substrate 310 on which the photoelectric conversion unit 340 is formed. The second electrode forming unit 150 forms the second conductive layer 350 through, for example, a sputtering method, a low pressure chemical vapor deposition (LPCVD) method, or an evaporation method.

The second conductive layer 350 may be formed of a conductive light reflecting material to reflect light incident from the substrate 310 side. For example, the second conductive layer 350 may be formed of a single metal such as silver, aluminum, zinc, molybdenum, or an alloy thereof, or may be formed of an oxide of the single metal or alloy. On the contrary, when the direction in which light is incident is opposite, the second conductive layer 350 may be formed of a transparent conductive material for transmitting light.

1 and 17, the substrate 310 on which the second conductive layer 350 is formed in the second electrode forming unit 150 is transferred to the third patterning unit 160 through the transfer device 170. The third patterning unit 160 patterns the second conductive layer 350 to form a second electrode 352. The third patterning unit 160 includes a laser supplier 162 supplying a laser for patterning the second conductive layer 350. Since the laser supplier 162 included in the third patterning unit 160 has substantially the same configuration as the laser supplier 122 included in the first patterning unit 120, a detailed description thereof will be omitted.

Meanwhile, when patterning the second conductive layer 350, the photoelectric converter 340 may also be patterned at the same time. Therefore, a plurality of solar cells 360 are formed by patterning the second conductive layer 350 and the photoelectric conversion unit 340. In this case, a part of the second electrode 352 is electrically connected to the first electrode 322 of the adjacent solar cell 360 through a hole formed in the photoelectric conversion unit 340. Accordingly, the solar cells 360 may be connected in series or in parallel to produce a desired amount of power.

In the third patterning unit 160, the substrate 310 on which the formation of the second electrode 352 is completed is unloaded through the transfer device 170, and finally, the solar cell in which the plurality of solar cells 360 are formed. The manufacture of is completed.

Meanwhile, the solar cell manufacturing system 100 may further include a cleaning unit (not shown) installed at the front end of the first electrode forming unit 110. The cleaning unit receives the substrate 310 from the transfer device 170 and cleans the surface of the substrate 310. For example, the cleaning unit may clean the surface of the substrate 310 through wet cleaning.

In addition, the solar cell manufacturing system 100 may further include a texturing unit (not shown) installed at the rear end of the first electrode forming unit 110. The texturing part performs a texturing process to form fine unevenness on the surface of the first conductive layer 320 in order to increase light absorption. The texturing part may, for example, texturize the surface of the first conductive layer 320 through a wet etching process.

According to the solar cell manufacturing system as described above, by connecting in-line several devices for manufacturing a solar cell, it is possible to improve the process efficiency and reduce the manufacturing cost. In addition, by using a process chamber having a split electrode structure, it is possible to easily deposit an intrinsic silicon layer in which amorphous silicon layers and microcrystalline silicon layers are alternately stacked, thereby manufacturing a solar cell having improved photoelectric efficiency. .

In the detailed description of the present invention described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art having ordinary skill in the art will be described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

1 is a configuration diagram schematically showing a solar cell manufacturing system according to an embodiment of the present invention.

2 to 4 and 15 to 17 are schematic cross-sectional views showing the manufacturing process of the solar cell according to an embodiment of the present invention for each process step.

5 is a perspective view illustrating in detail the thin film deposition unit illustrated in FIG. 1.

FIG. 6 is a plan view of the thin film deposition unit illustrated in FIG. 5.

FIG. 7 is a plan view schematically illustrating the interior of the central chamber illustrated in FIG. 5.

FIG. 8 is a cross-sectional view illustrating an embodiment of the intrinsic silicon layer illustrated in FIG. 4.

9 is a schematic view of a second process chamber in accordance with one embodiment of the present invention.

FIG. 10 is a perspective view illustrating the split electrode assembly illustrated in FIG. 9.

11 is a schematic view of a second process chamber in accordance with another embodiment of the present invention.

12 to 14 are views illustrating various configuration methods of the laser supply unit illustrated in FIG. 11.

<Explanation of symbols for the main parts of the drawings>

100: solar cell manufacturing system 110: first electrode forming portion

120: first patterning unit 140: second patterning unit

150: second electrode forming portion 160: third patterning portion

170: transfer device 200: thin film deposition unit

210: central chamber 220: first process chamber

230: second process chamber 240: third process chamber

250: loading / unloading unit 310: substrate

320: first conductive layer 322: first electrode

330: photoelectric conversion layer 340: photoelectric conversion part

350: second conductive layer 352: second electrode

360: thin film solar cell 430: split electrode assembly

432: constant voltage electrode 434: negative voltage electrode

510: laser supply

Claims (16)

A first electrode forming part forming a first conductive layer on the substrate; A first patterning part forming the first electrode by patterning the first conductive layer; At least one thin film for depositing a photoelectric conversion layer on a substrate on which the first electrode is formed using at least one process chamber having a split electrode assembly including a plurality of constant voltage electrodes and a plurality of negative voltage electrodes for generating a plasma Evaporation unit; A second patterning unit patterning the photoelectric conversion layer to form a photoelectric conversion unit; A second electrode forming part forming a second conductive layer on the substrate on which the photoelectric conversion part is formed; And And a third patterning unit patterning the second conductive layer to form a second electrode. The method of claim 1, The constant voltage electrodes and the negative voltage electrodes have at least one array structure selected from an alternating linear array structure, a matrix-like array structure, an mutually alternate spiral array structure, and an alternate alternating concentric array structure. Manufacturing system. The method of claim 1, wherein the thin film deposition unit, A central chamber including a substrate transfer unit for transferring the substrate; A first process chamber for depositing a first impurity doped silicon layer on the substrate transferred by the substrate transfer unit; At least one second process chamber for depositing an intrinsic silicon layer on the substrate on which the first impurity doped silicon layer is formed; And And a third process chamber for depositing a second impurity doped silicon layer on the substrate on which the intrinsic silicon layer is formed. The method of claim 3, At least one of the first process chamber, the second process chamber and the third process chamber further comprises a laser supply unit for supplying a laser into the chamber body. The method of claim 4, wherein the laser supply unit, And at least one laser generator installed outside the chamber body to supply a laser to the inside of the chamber body. The method of claim 5, wherein the laser supply unit, And at least one reflective member reflecting the laser output from the laser generator to form a plurality of laser scan lines in the chamber body. The method of claim 3, At least one of the first process chamber, the second process chamber and the third process chamber, the solar cell further comprises a remote plasma generator which is provided outside the chamber body for supplying plasma to the interior of the chamber body Manufacturing system. The method of claim 1, And the second process chamber alternately deposits a plurality of amorphous silicon layers and a plurality of microcrystalline silicon layers to form the intrinsic silicon layer. The method of claim 8, And the second process chamber alternately deposits the amorphous silicon layer and the microcrystalline silicon layer by changing a frequency of radio frequency power supplied to the split electrode assembly. The method of claim 1, The first impurity doped silicon layer is formed of a p-type silicon layer containing a p-type impurity, And the second impurity doped silicon layer is formed of an n-type silicon layer including n-type impurities. The method of claim 10, The first conductive layer is formed of a transparent conductive material, The second conductive layer is a solar cell manufacturing system, characterized in that formed of a conductive light reflecting material. The method of claim 1, And a transfer device for sequentially transferring a substrate to the first electrode forming portion, the first patterning portion, the thin film deposition portion, the second patterning portion, the second electrode forming portion, and the third patterning portion. A solar cell manufacturing system characterized by the above-mentioned. The solar cell manufacturing system of claim 12, wherein the first patterning unit, the second patterning unit, and the third patterning unit include a laser supplier for supplying a laser for patterning a thin film. The solar cell manufacturing system of claim 13, wherein the laser supplier supplies a laser to a substrate installed at a lower portion of the transfer apparatus and passed to an upper portion of the transfer apparatus. The method of claim 1, The solar cell manufacturing system is installed at the front end of the first electrode forming portion, further comprising a cleaning unit for cleaning the surface of the substrate. The method of claim 1, And a texturing unit configured to receive the substrate on which the first conductive layer is formed and to texturize the first conductive layer.

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