KR100933193B1 - Thin film manufacturing apparatus and thin film manufacturing method - Google Patents

Abstract

The thin film manufacturing apparatus of the present invention includes a chamber, a substrate support provided at a lower portion of the chamber to support a substrate, at least one target support provided to oppose the substrate support to support a target, and at least partially inserted into the chamber. At least one evaporation source providing a deposition gas therein.

The invention as described above has the effect of obtaining a thin film for a solar cell having a high quality by simultaneously depositing copper, indium, gallium and selenium having different deposition methods.

Solar Cell, CIGS, Light Absorption Layer, Sputter, Evaporation Source

Description

Thin film manufacturing apparatus and thin film manufacturing method {APPARATUS AND METHOD FOR MANUFACTURING THIN FILM}

The present invention relates to a thin film manufacturing apparatus, and more particularly, to a thin film manufacturing apparatus and a thin film manufacturing method for forming a solar cell having a high efficiency.

In general, a method of using solar energy is largely divided into a method using solar heat and a method using solar light. The method of using solar heat is to heat and generate electricity using water heated by the sun, and the method of using solar light can generate electricity by using the light of the sun to operate various machines and appliances. That's how.

Of these, solar cells using solar light use unlimited solar energy without pollution, so there is no need for fuel costs, no air pollution or waste generation, and no mechanical vibration and noise since the power generation part is made of semiconductor devices. In addition, the solar cell has a long life of at least 20 years, easy to automate the power generation system, and has the advantage of minimizing the cost of operation and maintenance.

Solar cells using such photovoltaic are typically crystalline silicon solar cells, amorphous silicon solar cells, CIGS (Gu-In-Ga-Se) solar cells, GaAs solar cells, CdTe solar cells, etc., in particular formed on CIGS solar cells CIGS, a compound semiconductor, has a direct transition energy bandgap of 1 eV or more, and has the highest light absorption coefficient among semiconductors, and is very optically stable, making it an ideal material for the light absorption layer of solar cells. The battery has the advantages of high efficiency and durability.

Such a CIGS solar cell is generally deposited by mixing a compound of CIGS, ie, copper (Cu), indium (In), gallium (Ga), selenium (Se), on a glass substrate coated with molybdenum (Mo) and Cadmium sulfide (CdS), zinc oxide (ZnO), and magnesium fluoride (MgF 2) are sequentially formed thereon, and then an aluminum (Al) electrode is finally formed on the top of magnesium fluoride. Here, the most important factor for determining the efficiency of CIGS solar cells is the quality of the CIGS film, and sputtering or evaporation is commonly used to form a CIGS film having high efficiency.

In the case of forming a CIGS film by conventional sputtering, when sputtering copper, indium, gallium and selenium at the same time, sputtering is performed sequentially on copper, indium and gallium because the ions of selenium inflict great damage to the film formation itself. Thereafter, selenium is evaporated to form a CIGS film on the substrate. Further, when forming a CIGS film by conventional evaporation deposition, copper, indium, gallium and selenium are simultaneously evaporated using an evaporation source, and the evaporated gas is sprayed from the bottom of the substrate toward the substrate, thereby forming a CIGS film on the substrate.

However, in the former case, since sputtering and evaporation deposition are difficult to occur in the same chamber, sputtering and evaporation deposition are performed in different chambers, thereby making it difficult to properly mix copper, indium, gallium, and selenium. The problem that the efficiency of the battery is lowered occurs. In addition, it takes a long time because each deposition is performed in different chambers, which causes a problem of poor work efficiency.

In the latter case, it is easy to uniformly mix copper, indium, gallium and selenium by depositing them simultaneously, but it is difficult to control each vaporization temperature because the vaporization temperatures of copper, indium, gallium and selenium are different from each other. It is difficult to obtain a thin film of. In addition, since conventional evaporation deposition uses a high temperature evaporation source due to high evaporation temperature of copper, indium, gallium, and the like, the film can be formed only by a bottom-up deposition method. It causes a fatal problem.

In order to solve the above problems, an object of the present invention is to provide a thin film manufacturing apparatus and a thin film manufacturing method for simultaneously depositing copper, indium, gallium deposited by sputtering and selenium deposited by evaporation deposition.

In addition, an object of the present invention is to provide a thin film manufacturing apparatus and a thin film manufacturing method for increasing the efficiency of CIGS solar cells.

In order to achieve the above object, the thin film manufacturing apparatus of the present invention comprises a chamber, a substrate support provided in the lower portion of the chamber to support the substrate, at least one target support provided to face the substrate support and support the target, At least a portion is inserted into the chamber and includes at least one evaporation source for providing deposition gas in the chamber.

The evaporation source may include a body, an injection hole formed at the tip of the body, and a gas supply passage connected between the crucible and the injection hole to communicate the crucible with the injection hole. A heating member may be further provided between the body and the gas supply passage.

The evaporation source may include a gas injector provided in the chamber and having a spray hole formed on one surface thereof, a crucible provided outside the chamber to provide deposition gas to the gas injector, and a gas supply passage connected between the gas injector and the crucible. have. A heating member may be further provided outside the gas supply passage.

The evaporation source includes an injector and a crucible connected to the injector, wherein a part of the injector may be disposed in the chamber.

The substrate support may further be provided with a heating member. A driver is connected to the lower part of the substrate support, and the driver may rotate the substrate support about a vertical axis.

The substrate support may include a support plate, a moving plate provided on an upper portion of the support plate and having a heating member therein, and a driving shaft for rotating the moving plate from a horizontal state to a vertical state. The target support may be provided to face the moving plate in a vertical state.

The substrate support may include a support for supporting the substrate and a roller for horizontally moving the support. A heating member may be further provided below the substrate support. Both side walls of the chamber may be provided with a substrate entrance for entering and withdrawing the substrate, respectively.

In addition, in order to achieve the above object, the present invention is a thin film manufacturing method for depositing a CIGS film on a substrate, the step of depositing at least one of copper, indium, gallium by the sputtering method, and depositing selenium by the evaporation deposition method And depositing selenium may be performed simultaneously with the deposition of at least one of copper, indium, and gallium.

The copper, indium and gallium may be deposited respectively, and copper, indium and gallium may be deposited in combination with each other. Copper, indium, gallium, selenium may be deposited in the same chamber or in each chamber.

In addition, in order to achieve the above object, the present invention is a thin film manufacturing method for manufacturing a solar cell, the step of depositing molybdenum on the substrate, the step of simultaneously depositing copper, indium, gallium and selenium, cadmium sulfide And depositing zinc oxide, and forming and wiring aluminum electrodes, wherein copper, indium, and gallium are deposited by sputtering, and selenium may be deposited by evaporation.

The method may further include depositing magnesium fluoride between depositing the zinc oxide and forming the aluminum electrode.

The present invention has the effect of obtaining a thin film for a solar cell having a high quality by simultaneously depositing copper, indium, gallium and selenium having different deposition methods.

In addition, the present invention has the effect of reducing the process time and work efficiency because the operation is performed in the same chamber of copper, indium, gallium and selenium.

In addition, the present invention has the effect of preventing the substrate from bending when forming a thin film on a large area of the substrate because the process proceeds in a state in which the substrate is supported in a horizontal state or a vertical state.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to the fullest extent. It is provided to inform you. Like reference numerals in the drawings refer to like elements.

1 is a cross-sectional view showing a thin film manufacturing apparatus according to the present invention, Figures 2 to 6 is a cross-sectional view showing a modification of the thin film manufacturing apparatus according to the present invention, Figure 7 is a manufacturing process of a CIGS solar cell according to the present invention 8 and 9 are flowcharts illustrating a method of forming a CIGS film according to the present invention on a substrate.

Referring to FIG. 1, the apparatus for manufacturing a thin film according to the present invention is provided with a chamber 100, a substrate support 200 provided below the chamber to seat the substrate G, and a surface facing the substrate support 200. Target support 310 is provided with a target 300, and the evaporation source 400 provided on at least one side of the target support 310.

The chamber 100 is formed in a rectangular box or cylindrical shape, and a predetermined space is provided inside the chamber 100 so as to process the substrate G. The shape of the chamber 100 is not limited and is preferably formed in a shape corresponding to the shape of the substrate G. That is, in this embodiment, a rectangular glass substrate is used, and thus, the shape of the chamber 100 is preferably formed in a rectangular box shape, which is a shape corresponding to the glass substrate G. One side wall of the chamber 100 is formed with a substrate gate (Gate, 110) through which the substrate (G) is drawn in and out, and the substrate gate (110) introduces a substrate (G) to be processed or a substrate (G) which has been processed. Or withdrawal. Here, the substrate entrance 110 is formed only on one side of the chamber 100, but is not limited thereto, and may be formed on opposite side walls of the chamber 100. In addition, the bottom surface of the chamber 100 is connected to the exhaust device 120, for example, a turbo molecular pump for forming a vacuum degree in the chamber 100 during the deposition process. Although the chamber 100 has been described as an integrated body, the chamber 100 may be divided into a lower chamber having an upper opening and a chamber lead covering the upper part of the lower chamber.

The substrate support 200 is provided below the chamber 100, and serves to seat the substrate G introduced into the chamber 100. Typically, the shape of the substrate support 200 is preferably formed in a shape corresponding to the shape of the substrate G, and in the present embodiment, preferably, the shape of the substrate support 200 is formed in a square shape corresponding to the shape of the glass substrate G. A driving member 210 for rotating the substrate support 200 is connected to the lower portion of the substrate support 200. In addition, a heating member 220 may be further provided inside the substrate support 200 to heat the substrate G mounted on the substrate support 200 to a predetermined temperature, and the heating member 220 may be a substrate support. A predetermined heat is applied to the substrate G seated on the 200 to improve the reactivity with the deposition material deposited on the substrate G. Here, for example, a resistance heating heater may be used as the heating member 220. In the above, although one substrate support 200 is provided in the chamber 100, the present invention is not limited thereto, and a plurality of substrate support 200 may be provided. In addition, although one substrate G is mounted on the substrate support 200, a plurality of substrates G may be mounted.

The upper part of the substrate support 200 is provided with a target 300 made of a deposition material to be deposited on the upper surface of the substrate (G), the target 300 is the upper inner wall of the chamber 100 by the target support 310 Is fixed to. In the present embodiment, a deposition material such as copper, indium, or gallium may be used as the target 300, and one or more alloys may be used as the target 300 in combination thereof. One side of the target 300 is connected to the power supply unit 320 for applying a voltage to the target 300, a negative charge is typically applied to the target 300. In addition, a magnet (not shown) may be further provided on the rear surface of the target 300, and the magnet serves to trap electrons formed in the chamber 100 near the target 300.

When a negative charge is applied to the target 300, the sputter gas reacts with the sputter gas injected into the chamber 100 to ionize the sputter gas, and the ionized sputter gas collides with the target 300. Here, the sputter gas ionized by the magnet provided on the rear surface of the target 300 continuously collides with the target 300, whereby the deposition material separated from the target 300 accelerates toward the substrate G and the substrate. (G) is deposited on the upper surface.

In the above, although the thin film manufacturing apparatus having one target 300 is illustrated, the present invention is not limited thereto, and a plurality of targets may be provided in the chamber. That is, as shown in FIG. 2, a plurality of evaporation sources 400 are provided in the upper portion of the chamber 100, and a plurality of targets 300a, 300b, and 300c are provided to be adjacent to the plurality of evaporation sources 400. The plurality of targets 300a, 300b, 300c are supported by the respective target supports 310a, 310b, 310c, and the plurality of target supports 310a, 310b, 310c are fixed to the upper inner wall of the chamber 100. Here, the power supply units 320a, 320b, and 320c for applying a voltage to the targets 300a, 300b, and 300c are connected to the plurality of targets 300a, 300b, and 300c, respectively.

In the above, although the power supply unit is provided in the number corresponding to the number of targets, one power supply unit may be connected to each of the plurality of targets to simultaneously apply voltage. In addition, in the above, three targets are provided in the chamber. However, the targets may be fixed to the sidewalls of the chamber.

1, the evaporation source 400 is provided through one side of the target, specifically the upper portion of the chamber 100, the evaporation source 400 is a body 410, the injection hole 440 is formed at the front end, It includes a crucible 420 provided in the body 410, and a gas supply passage 430 connecting the crucible 420 and the injection hole 440.

Body 410 is formed in a cylindrical or polygonal box shape, the injection hole 440 is formed at the front end of the body 410. In addition, a crucible 420 in which the deposition material is stored is provided inside the body 410, and the gas supply passage 430 is connected to communicate the crucible 420 with the injection hole 440. Here, a heating member (not shown) such as a heater may be provided between the body 410 and the crucible 420, and the heating member may heat the deposition material to vaporize the deposition material. Play a role. Here, of course, a plurality of injection holes 440 formed at the front end of the body 410 may be formed.

When the deposition material is supplied to the crucible 420 provided inside the body 410 and vaporized by the heating member, the vaporized deposition material passes through the gas supply passage 430 and the injection hole 440 to the chamber 100. ) Is sprayed inside. Subsequently, the vaporized deposition material injected into the chamber 100 moves toward the substrate G, thereby depositing a uniform thin film on the substrate G. In the above, the evaporation source 400 is fixed to face the substrate G. However, the evaporation source 400 is not limited thereto, and the injection direction of the evaporation source 400 may be adjusted.

Conventionally, by performing the sputtering and evaporation deposition of the CIGS film in different chambers, copper-indium-gallium-selenium is not mixed well, which causes a problem of degrading the quality of the CIGS film. In addition, when the CIGS film is manufactured using only evaporation deposition, the process cannot be performed in an upward manner from the bottom of the substrate, and thus, the substrate is warped when a large area substrate is used.

In contrast, the present invention provides a target and an evaporation source simultaneously in one chamber, and by depositing a CIGS film on the substrate in a downward manner, it is possible to stably support the lower surface of the substrate, which is stable to a large area substrate CIGS thin film Can be formed. In addition, by having an evaporation source having a high deposition efficiency in addition to the sputtering method, there is an advantage to increase the efficiency of the CIGS film deposited on the substrate. In particular, the thin film is manufactured by evaporating and depositing a material having high evaporation temperature (Gu, In, Ga) by sputtering and simultaneously evaporating and depositing a material having low evaporation temperature. It is easy to manufacture.

The evaporation source as described above may be configured as follows. That is, as shown in FIG. 3, the target support 310 having the target 300 is connected to the upper inner wall of the chamber 100 at an upper portion of the chamber 100, and linearly adjacent to the target support 310. A plurality of types of evaporation sources 500 are provided. The linear evaporation source 500 may include a gas injector 510 for injecting vaporized deposition material into the chamber 100, a gas supply passage 520 for supplying vaporized deposition material to the gas injector 510, and And a crucible 530 that provides a vaporized deposition material to the gas supply passage 520. The gas injection part 510 is provided in the chamber 100 and is formed in a plate shape of a rod shape. A plurality of injection holes 512 are formed in the lower surface of the gas injection unit 510, and the vaporized deposition material supplied to the gas injection unit 510 is supplied into the chamber 100 through the injection hole 512. The gas supply passage 520 is connected to the upper portion of the gas injector 510 to supply the vaporized deposition material to the gas injector 510, and the gas supply passage 520 extends outside the chamber 100. Is formed. A crucible 530 in which the deposition material is stored is connected to an end of the gas supply passage 520 provided outside the chamber 100, and the crucible 530 serves to vaporize the deposition material. The crucible 530 may store a deposition material, and a heating member 532 such as a heater may be provided inside the crucible 530 to vaporize the deposition material.

When the deposition material is stored in the crucible 530, the heating member 532 provided inside the crucible 530 applies a predetermined heat to the deposition material to vaporize the deposition material, and the vaporized deposition material is a gas supply flow path. The gas is injected to the gas injector 510 via 520. The vaporized deposition material moved to the gas injector 510 is injected into the chamber 100 through an injection hole 512 formed in the gas injector 510. Here, a heating unit (not shown) such as a heater may be further provided along the outer circumference of the gas supply passage 520, and the heating unit may be condensed in the gas supply passage 520 while the vaporized deposition material moves. Can be prevented.

In addition, as shown in FIG. 4, a target support 310 having a target 300 is connected to an upper inner wall of the chamber 100 at an upper portion of the chamber 100, and a pointer type is provided at a side wall of the chamber 100. A plurality of evaporation sources 600 are provided. The pointer type evaporation source 600 includes an injector 610 for injecting vaporized deposition material into the chamber 100 and a crucible 620 connected to the injector 610. A portion of the injector 610 is provided in the chamber 100 and penetrated so as to extend outside the chamber 100. Here, an injection hole 612 is formed at the tip of the injector 610 provided in the chamber 100 to inject the vaporized deposition material into the chamber 100. A crucible 620 is connected to an end of the injector 610 provided outside the chamber 100, and the crucible 620 serves to vaporize the deposition material.

In the above, the evaporation source is illustrated as a linear type evaporation source 500 and a pointer type evaporation source 600, respectively, but it is a matter of course that the combination may be provided in the chamber 100. In addition, although the linear type evaporation source 500 and the pointer type evaporation source 600 are installed on the upper side and the sidewall in the chamber 100, respectively, the present invention is not limited thereto and may be formed at any position in the chamber 100. to be.

Although the deposition material is deposited on the upper surface of the substrate G while the substrate G is in a horizontal state, the deposition material may be deposited on the substrate G by arranging the substrate G in the vertical direction as follows. have. That is, as shown in FIG. 5, the thin film manufacturing apparatus includes a chamber 100, a substrate support 700 provided at a lower portion of the chamber 100, and a sidewall of the chamber 100. The provided target support 310 and the evaporation source 400 provided adjacent to the target support 310. Here, since the configuration except for the substrate support 700 is the same as the configuration described above, it will be omitted.

The substrate support 700 is provided in the lower portion of the chamber 100, and the support plate 710, the movable plate 720 provided on the upper portion of the support plate 710, and the movable plate 720 in a horizontal state. A drive shaft 730 for rotating in the vertical state.

The support plate 710 is installed in the lower portion of the chamber 100, and the moving plate 720 is provided on the upper portion of the support plate 710 in a size corresponding to the support plate 710. One side of the support plate 710 and one side of the moving plate 720 is connected to the driving shaft 730 overlapping to connect the support plate 710 and the moving plate 720. The substrate G is seated on the upper portion of the movable plate 720, and a heating member 722 is provided inside the movable plate 720 to heat the seated substrate G to a predetermined temperature.

When the substrate G is seated on the upper portion of the moving plate 720 while the moving plate 720 is horizontal, the moving plate 720 rotates vertically by the drive shaft 730 to vertically move the substrate G. Place it in a state. Subsequently, sputtering and evaporation are simultaneously performed on one surface of the substrate G by the target 300 and the evaporation source 400 provided to face the substrate G disposed in a vertical state, so that deposition is performed on one surface of the substrate G. do.

In the above configuration, by forming a thin film on one surface of the substrate G in a state in which the substrate G is disposed vertically, the substrate G can be stably supported, whereby the process of the substrate G is performed. There is an effect that can form a thin film stably on a large area of the substrate (G) without bending. In addition, by simultaneously providing the target 300 with the evaporation source 400 having a high deposition efficiency in the chamber 100, there is an effect that can increase the efficiency of the thin film deposited on the substrate (G).

In the above, the substrate G is introduced into the chamber 100 in a horizontal state and moved to a vertical state, and then a deposition material is deposited on one surface of the substrate G, but the substrate is fixed in a vertical state. After (G) is drawn in a vertical state and seated on one surface of the moving plate 720, the deposition process may be performed.

In addition, although the deposition material is deposited on one surface of the substrate G while the substrate G is disposed vertically, the deposition material may be deposited on the substrate G in an inline manner as follows. have. As shown in FIG. 6, the thin film manufacturing apparatus includes a chamber 100, a substrate support 800 provided at a lower portion of the chamber 100, a heating member 900 provided at a lower portion of the substrate support 800, and And a target support 310 provided at an upper portion of the chamber 100 to support the target 300, and an evaporation source 400 provided adjacent to the target support 310. Here, since the configuration except for the substrate support 700 is the same as the configuration described above, it will be omitted.

The substrate support 800 is provided under the chamber 100, and the substrate support 800 is provided under the support 810 for supporting the substrate G, and is provided under the support 810 to horizontally support the support 810. And a roller 820 for moving. The support 810 supports both sides of the lower surface of the substrate G, and serves to horizontally transfer the substrate G drawn from the substrate entrance 110a. Here, the rollers 820 for moving the support 810 in the horizontal direction are arranged at equal intervals along the transfer direction of the substrate. A heating member 900, for example, a heater is provided under the substrate support 800, and the heating member 900 serves to provide a predetermined heat to the substrate G while the substrate G is transferred. do. Here, the substrate entrances 110a and 110b for drawing in and out of the substrate G are provided on opposite side walls of the chamber 100.

When the substrate G is inserted from the substrate entrance 110a and seated on the support 810, the substrate G seated on the support 810 is moved horizontally by the support 810. In this case, the heating member 900 provided below the substrate support 800 provides a predetermined heat to the substrate G while the substrate G is moved. Subsequently, the deposition material moves from the plurality of deposition sources provided on the substrate G seated on the support 810, that is, the target 300 and the evaporation source 400, while the substrate G moves. Sputtering and evaporation are carried out at the same time to perform deposition.

As described above, the target 300 and the evaporation source 400 are simultaneously provided in the in-line chamber 100, thereby increasing the processing speed of the large-area substrate G and increasing the deposition efficiency of the thin film. have.

In the above, although a plurality of targets and evaporation sources are provided in one chamber, the present invention is not limited thereto. For example, at least one target and evaporation source may be provided in a plurality of chambers. If the target and the evaporation source is provided, of course, it can be configured by connecting the three chambers inline.

Hereinafter, a method of forming a CIGS film on a substrate using a CIGS solar cell, for example, using a thin film manufacturing apparatus according to the present invention.

As shown in FIG. 7, the method of manufacturing a CIGS solar cell includes forming a back electrode layer on a substrate (S10), forming a light absorbing layer (S20), and forming a buffer layer (S30). And forming a window layer (S40), forming an anti-reflection layer (S50), and forming a grid electrode layer and wiring an electrode (S60).

The substrate 10 is formed of sodium lime glass having a thickness of 1 to 3 mm. When the substrate S is prepared, the substrate S is washed with an alkali glass cleaning solution and rinsed with ultra pure water to wash the substrate 10. The substrate 10 may be a ceramic substrate such as alumina, a stainless steel, a copper-type metal substrate, a polymer, or the like, in addition to the sodium carbonate lime glass.

When the cleaning of the substrate 10 is finished, a step (S20) of forming a back electrode layer is performed. The back electrode layer 20 uses molybdenum as an electrode having low specific resistance, no peeling phenomenon due to a difference in thermal expansion coefficient, and excellent adhesion to the glass substrate 10. In the present embodiment, the back electrode layer 20 deposits molybdenum to a thickness of 0.5 to 1 μm on one surface of the substrate 10 by a DC sputter method. Here, nitrogen may be used as the sputter gas.

Subsequently, in operation S20, the light absorption layer is formed while a part of the rear electrode layer 20 is masked. As the light absorption layer 30, a compound semiconductor in which copper, indium, gallium, and selenium is mixed is used, which is the most efficient energy conversion solar cell. It is deposited simultaneously on top of 20. Here, the light absorption layer 30 is formed to a thickness of approximately 2μm.

Hereinafter, a method of forming a light absorption layer using CIGS will be described in detail using a thin film production apparatus according to the present invention.

As shown in FIG. 8, a method of forming a light absorbing layer for a solar cell using a CIGS film includes depositing a substrate (A10), simultaneously depositing copper-selenium (A20), and simultaneously depositing indium-selenium. And a step (A40) of depositing gallium-selenium at the same time, and a step (A50) of extracting a substrate on which deposition is completed. Here, the method of forming the CIGS film to form the light absorption layer will be described with reference to the thin film manufacturing apparatus of FIG. 6.

First, a sodium carbonate lime glass substrate G having molybdenum deposited on one surface thereof is seated on a support 810 provided in the chamber 100 to perform a step of introducing the substrate (A10). Here, the temperature of the substrate (G) is maintained at about 500 degrees during the process, and as a deposition material deposited on the substrate (G), a plurality of target supports (310) are sequentially mounted with copper, indium, gallium, respectively, Selenium is prepared in the evaporation source 400. Furthermore, when the initial interior degree of vacuum is formed of 10 ^-6 Torr, and the process begins degree of vacuum for the process of the chamber 100 is 10 ^-2 to ¹⁰ to form the ^first.

Subsequently, the substrate G seated on the support 810 starts to move horizontally by the support 810. When the substrate G mounted on the support 810 is positioned below the target support 310 on which the copper target 300 is mounted, negative charge is applied to the copper target 300 by the power supply unit 320 connected to the copper. As a result, a deposition material separated from the copper target 300 is deposited on the upper surface of the substrate G. At the same time, a step of simultaneously depositing copper-selenium by spraying selenium vaporized on the upper surface of the substrate G from the evaporation source 400 installed adjacent to the target support 310 on which the copper target 300 is mounted (A20). Here, the evaporation source 400 may be a linear evaporation source or a pointer type evaporation source.

After the deposition of the copper-selenium, the substrate G is continuously moved, and when positioned below the target support 310 on which the indium target 300 is mounted, the indium is deposited on the substrate G by sputtering as above. At the same time, the deposition of indium selenium is performed by spraying and depositing selenium vaporized by evaporation on the substrate G (A30).

After the deposition of copper-selenium and indium-selenium, the substrate G is continuously moved in a horizontal state and positioned below the target support 310 on which the gallium target 300 is mounted. A selenium is deposited on the substrate G at the same time by sputtering and evaporation, thereby simultaneously depositing gallium-selenium (A40). Here, since the substrate G is heated to about 500 degrees, the previously deposited copper-selenium, indium-selenium, and gallium-selenium compounds of copper-indium-gallium-selenium are deposited on top of the substrate G during deposition. This is mixed evenly. Of course, a further heat treatment process may be added to more evenly mix the compound of copper-indium-gallium-selenium.

In the above, the process is performed while the substrate G is stopped at the lower portion of the plurality of target supports 310, but the process may be performed while the substrate G is continuously moved without stopping the substrate G.

As described above, the substrate G, which has completed the deposition of copper-selenium, indium-selenium, and gallium-selenium, is transferred to the outside of the chamber 100 to complete a step of drawing out a substrate on which deposition is completed (A50).

In the above, copper-selenium, indium-selenium, and gallium-selenium were sequentially deposited on the rear electrode layer, but the order of deposition may be changed. In addition, in the above, deposition was performed by mounting copper, indium, and gallium as targets, respectively, but a target of two alloy forms such as copper-indium and copper-gallium may be formed, and copper-indium-gallium may be used as one alloy form. Of course, it is possible to form a target. In addition, although the CIGS film was deposited on the substrate using the thin film manufacturing apparatus shown in FIG. 6, it is, of course, applicable to the thin film manufacturing apparatus shown in FIG. 2.

In addition, as shown in FIG. 9, a method of forming a light absorption layer using a CIGS film in a solar cell includes preparing a substrate (B10), simultaneously depositing copper-indium-gallium-selenium (B20) and The method may include extracting the substrate on which deposition is completed (B30). Here, a method of forming a light absorption layer using a CIGS film in a solar cell will be described with reference to the thin film manufacturing apparatus of FIG. 1. In addition, description overlapping with the above is omitted.

First, a step (B10) of inserting the substrate is performed by mounting the substrate G having the rear electrode layer formed on one surface thereof, on the substrate support 200 provided in the chamber 100. Here, the temperature of the substrate G is maintained at about 500 degrees while the process is in progress, and the initial vacuum degree and the process vacuum degree in the chamber 100 are 10 ⁻⁶ Torr and 10 ⁻² Torr, respectively. In addition, the target support 310 is mounted with copper, indium, gallium as the target 300, selenium is provided to the evaporation source 400. Here, the target support 310 is mounted by dividing copper, indium and gallium.

Subsequently, the substrate G seated on the substrate support 200 starts to rotate by the substrate support 200, and a negative charge is applied to the copper, indium, and gallium targets by the power supply unit 320 connected to the target 300. The deposition material thereby separated from the copper, indium and gallium targets is deposited on the top surface of the substrate (G). At the same time, the vaporized selenium gas is injected into the evaporation source 400 toward the substrate, thereby completing step B20 in which selenium is simultaneously deposited together with copper, indium, and gallium. Here, the evaporation source 400 may be a linear evaporation source or a pointer type evaporation source.

Here, since the substrate is heated to about 500 degrees, the previously deposited copper-indium-gallium-selenium is uniformly mixed on top of the back electrode layer during the deposition. After the deposition of the copper-indium-gallium-selenium as described above, the substrate G is transferred to the outside of the chamber 100 to complete the step (B30) of drawing out the substrate on which deposition is completed.

In the above, the target support 310 is divided into copper, indium and gallium, but is not limited thereto, and an alloy in which copper, indium and gallium are mixed may be mounted. In addition, although the CIGS film was deposited on the substrate using the thin film manufacturing apparatus illustrated in FIG. 1, the CIGS film may be applied to the thin film manufacturing apparatus illustrated in FIGS. 3, 4, and 5.

Returning to FIG. 7, after completing the step S20 of forming the light absorbing layer on the rear electrode layer 20, the step of forming the buffer layer on the light absorbing layer 30 is performed (S40). The buffer layer 40 is required for satisfactorily joining the P-type semiconductor located below the buffer layer 40 and the N-type semiconductor located above the buffer layer 40, and cadmium sulfide (CdS) is used as the buffer layer 40. do. Cadmium sulfide is formed at 0.05 μm by chemical bath deposition (CBD) method. In this example, the mixture of cadmium chloride, ammonium chloride, thiourea and ammonia was heated to about 80 degrees, and the substrate G was immersed in the mixture to crystallize n-type cadmium sulfide.

Subsequently, after the step of forming the buffer layer (S30), the step of forming the window layer on the buffer layer (S40) is performed. The window layer 50 functions as a transparent electrode on the front surface of the solar cell as an n-type semiconductor, and the window layer 50 is formed using zinc oxide (ZnO) having high light transmittance and high electrical conductivity. More specifically, the window layer 50 is formed to a thickness of 0.46 to 0.6 μm by using RF oxide sputtering method using zinc oxide. In the present embodiment, the deposition was performed by RF sputtering, but is not limited thereto, and may be deposited by reactive sputtering or metal organic chemical vapor deposition. In addition, a double structure may be used in which the ITO having excellent electro-optical properties is formed on the zinc oxide as the window layer 50.

Subsequently, an anti-reflection layer is formed on the window layer 50 (S50). The antireflection layer 60 serves to reduce reflection loss of sunlight incident on the solar cell, and the antireflection layer 60 is formed using magnesium fluoride (MgF _{2 )} . The antireflective layer 60 in this embodiment is formed by evaporation deposition which vaporizes the magnesium fluoride raw material and injects vaporized gas to the upper surface of the window layer 50, whereby the antireflective layer 60 is 0.08 To a thickness of 0.12 μm. Here, the anti-reflection layer 60 may be omitted from the solar cell configuration because it does not contribute to the development of the solar cell.

Subsequently, after the step of forming the anti-reflection layer (S50), the step of forming the grid electrode layer and wiring the electrode (S60) is performed. The grid electrode 70 serves to collect current from the surface of the solar cell, and the grid electrode 70 is formed using aluminum. The grid electrode 70 is formed to a thickness of 3 μm by evaporation of aluminum. Here, Ni / Al may be used instead of aluminum as the grid electrode 70. When the grid electrode 70 is formed, wires are connected between the grid electrode 70 and the back electrode layer 20 to apply a load between both electrodes to complete the manufacture of the solar cell.

Although described above with reference to the drawings and embodiments, those skilled in the art that the present invention can be variously modified and changed within the scope without departing from the spirit of the invention described in the claims below I can understand.

1 is a cross-sectional view showing a thin film manufacturing apparatus according to the present invention.

2 to 6 are cross-sectional views showing a modification of the thin film manufacturing apparatus according to the present invention.

7 is a cross-sectional view showing a manufacturing process of a CIGS solar cell according to the present invention.

8 and 9 are flowcharts illustrating a method of forming a CIGS film on a substrate according to the present invention.

             <Description of the code | symbol about the principal part of drawings>

100: chamber 110: substrate entrance

200: substrate support 300: target

310: target support 400: evaporation source

420: crucible 430: gas supply flow path

900: heating member G: substrate

Claims (20)

Chamber, A substrate support provided below the chamber to support the substrate; At least one target support provided opposite the substrate support to support the target such that a sputtered target material is deposited on the substrate in a downward manner; At least one evaporation source through which at least a portion of the chamber is inserted and provided in a downward manner in the chamber Thin film manufacturing apparatus comprising a. The thin film of claim 1, wherein the evaporation source comprises: a thin film including a body, a crucible provided in the body, a spray hole formed at the tip of the body, and a gas supply passage connected between the crucible and the spray hole to communicate the crucible with the spray hole. Manufacturing device. The thin film manufacturing apparatus of claim 2, further comprising a heating member between the body and the gas supply passage. The gas supply unit of claim 1, wherein the evaporation source is provided in a chamber, the gas injection unit having an injection hole formed on one surface thereof, a crucible provided outside the chamber to provide deposition gas to the gas injection unit, and a gas supply connected between the gas injection unit and the crucible. Thin film manufacturing apparatus containing a flow path. The thin film manufacturing apparatus according to claim 4, wherein a heating member is further provided outside the gas supply passage. The apparatus of claim 1, wherein the evaporation source comprises an injector and a crucible connected to the injector, wherein a part of the injector is disposed in the chamber. The apparatus of claim 1, wherein a heating member is further provided on the substrate support. The thin film manufacturing apparatus of claim 7, wherein a driving unit is connected to a lower portion of the substrate support, and the driving unit rotates the substrate support about a vertical axis. The thin film manufacturing method of claim 1, wherein the substrate support includes a support plate, a moving plate provided on an upper portion of the support plate, and a heating plate provided therein, and a driving shaft for rotating the moving plate from a horizontal state to a vertical state. Device. The thin film manufacturing apparatus of claim 9, wherein the target supporter is provided to face the moving plate in a vertical state. The apparatus of claim 1, wherein the substrate support is fixed in a vertical direction, and the target support is provided at a position facing the substrate support. The apparatus of claim 1, wherein the substrate support includes a support for supporting the substrate and a roller for horizontally moving the support. The thin film manufacturing apparatus of claim 12, wherein a heating member is further provided below the substrate support. The thin film manufacturing apparatus according to claim 12, wherein both sides of the chamber are provided with substrate entrances and exits for entering and withdrawing the substrate, respectively. In the thin film manufacturing method of depositing a CIGS film on a substrate, Sputtering at least one of copper, indium, and gallium and depositing the same by a downward deposition method; Evaporating selenium by vacuum vaporization in a vacuum, and evaporating downwardly, Depositing selenium is performed simultaneously with the deposition of at least one of copper, indium, and gallium. The method of claim 15, wherein the copper, indium, and gallium are deposited respectively. The method of claim 15, wherein the copper, indium, and gallium are deposited in combination with each other. 18. The method of claim 15, wherein the copper, indium, gallium, selenium is deposited in the same chamber or in each chamber. In the thin film manufacturing method which manufactures a solar cell, Depositing molybdenum on the substrate, Simultaneously depositing copper, indium, gallium and selenium, Depositing cadmium sulfide, Depositing zinc oxide, Forming and wiring aluminum electrodes, Deposition of the copper, indium, gallium and selenium at the same time, the step of sputtering at least one of copper, indium, gallium and deposited in a downward deposition method, A thin film manufacturing method comprising the step of evaporating selenium by vacuum evaporation in a vacuum down-deposition. 20. The method of claim 19, further comprising depositing magnesium fluoride between depositing zinc oxide and forming an aluminum electrode.

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