Heat treatment process system and method for heat-treating perovskite thin film using same

Abstract

According to the present embodiment, a heat treatment process system comprises: an upper heat treatment device for performing a heat treatment process on one or more substrates; a lower heat treatment device that is spaced apart from and faces the upper heat treatment device; and a conveyor belt that is disposed between the upper heat treatment device and the lower heat treatment device and conveys the substrate while supporting same. The heat treatment process system can transfer heat uniformly to the entirety of a perovskite thin film, and enables mass production of large-area perovskite thin films.

Description

Heat treatment process system and heat treatment method of perovskite thin film using the same

[0001] The present invention relates to a heat treatment process system and a heat treatment method of a perovskite thin film using the same.

[0002] To reduce global dependence on fossil fuels, research and development are actively underway on alternative and clean energy sources that are environmentally friendly and non-depletable. Among these, solar cells are semiconductor devices that directly convert light energy into electrical energy. They consist of two or more layers of light-absorbing semiconductor materials. When light is irradiated onto a semiconductor diode forming a pn junction, photons are absorbed, generating electron-hole pairs. This creates a potential difference at the junction between the two dissimilar materials, causing current to flow.

[0003] A solar cell considered a next-generation core technology is a perovskite solar cell, which is composed of a light-absorbing layer including a perovskite compound, an electron transport layer provided on one surface of the light-absorbing layer, and a hole transport layer provided on the other surface of the light-absorbing layer.

[0004] Meanwhile, the general structural formula of the perovskite structure is the AMX3 structure, in which an anion is located at the X site, a large cation is located at the A site, and a small cation is located at the M site.

[0005] These perovskite compounds have a wide range of applications due to their excellent electrical conductivity, charge mobility, and optical properties, and have various characteristics including long life, high absorption wavelength spectra due to small energy band gaps, and wide charge-carrier diffusion lengths. In addition, they have the advantages of being economical in material cost, can be produced in solution, have low process costs, and can be manufactured using low-temperature processes, and are attracting attention as promising materials for renewable energy applications. In particular, research is ongoing to use them as light absorbers for perovskite solar cells.

[0006] In general, perovskite thin films can be manufactured through a coating process, a drying process, and a heat treatment process. In this case, the heat treatment process can be performed by conducting heat to the perovskite thin film using a hot plate.

[0007] However, the heat treatment process using a hot plate has problems such as uneven heat transfer to the perovskite thin film due to uneven heat transfer and surface deviation of the hot plate, difficulty in applying a mechanical transport device for mass production, and difficulty in producing large-area perovskite thin films due to limitations in the size of the perovskite thin film according to the area of ​​the hot plate.

[0008] Embodiments of the present invention aim to provide a heat treatment device and a heat treatment method capable of uniformly transmitting heat to the entire perovskite thin film and mass-producing a large-area perovskite thin film.

[0009] In order to achieve the above-described object, one embodiment of the present invention discloses a heat treatment process system that performs a heat treatment process on one or more substrates, and includes an upper heat treatment device, a lower heat treatment device spaced apart from and facing the upper heat treatment device, and a conveyor belt disposed between the upper heat treatment device and the lower heat treatment device and configured to transport the substrate while supporting it.

[0010] Another embodiment of the present invention for achieving the above-described object discloses a heat treatment method for forming a perovskite thin film, which method uses a heat treatment process system including an upper heat treatment device, a lower heat treatment device disposed opposite to the upper heat treatment device, and a conveyor belt disposed between the upper heat treatment device and the lower heat treatment device, and includes a step of placing a substrate on the conveyor belt and a step of passing the substrate through a heating zone defined between the upper heat treatment device and the lower heat treatment device via the conveyor belt.

[0011] The heat treatment device according to an embodiment of the present invention uses an Inline Conveyer Oven capable of continuous processing, thereby enabling uniform heat transfer to the entire perovskite thin film and mass production of large-area perovskite thin films.

[0012] FIG. 1 is a schematic diagram illustrating an example of a heat treatment process according to one embodiment of the present invention.

[0013] FIG. 2 is a schematic drawing illustrating an example of a heat treatment device used in the heat treatment process of FIG. 1.

[0014] Figure 3 is a schematic diagram illustrating another example of the heat treatment process of Figure 1.

[0015] FIG. 4 is a flowchart illustrating an example of a method for manufacturing a perovskite thin film according to one embodiment of the present invention.

[0016] Figure 5 is a graph of temperature rise over time.

[0017] Figures 6 and 7 are XRD graphs of perovskite thin films.

[0018] In order to achieve the above-described object, one embodiment of the present invention relates to a heat treatment process system for performing a heat treatment process on one or more substrates, comprising an upper heat treatment device, a lower heat treatment device spaced apart from and facing the upper heat treatment device, and a conveyor belt disposed between the upper heat treatment device and the lower heat treatment device and configured to transport the substrate while supporting it.

[0019] The heat treatment device may include a rotating member, a rotating blade coupled to one side of the rotating member to control the flow of air, and a heater disposed in the direction of the air flow of the rotating blade.

[0020] The above heat treatment device further includes a cover member having an air discharge port formed therein, and air flowing through the heater can be discharged through the discharge port.

[0021] The above upper heat treatment device may include a plurality of devices arranged at intervals so as to be spaced apart from each other.

[0022] The lower heat treatment device may include a plurality of devices arranged to correspond to each of the plurality of upper heat treatment devices.

[0023] The upper heat treatment devices are arranged in three or more units at a constant interval, the lower heat treatment devices are arranged in three or more units to correspond to each of the three or more upper heat treatment devices, a heating zone may be defined in an area between the upper heat treatment devices and the lower heat treatment devices, and the heating zones may be defined in three or more units, and may be arranged so that the temperatures of air supplied from the upper heat treatment devices and the lower heat treatment devices are different for each heating zone.

[0024] The above conveyor belt may include a mesh shape.

[0025] Another embodiment of the present invention for achieving the above-described object relates to a heat treatment method for forming a perovskite thin film, which method comprises using a heat treatment process system including an upper heat treatment device, a lower heat treatment device disposed opposite to the upper heat treatment device, and a conveyor belt disposed between the upper heat treatment device and the lower heat treatment device, and comprising the steps of placing a substrate on the conveyor belt and passing the substrate through a heating zone defined between the upper heat treatment device and the lower heat treatment device via the conveyor belt.

[0026] The substrate may include a perovskite mixture coated on at least one surface.

[0027] The upper heat treatment devices are arranged in numbers of 3 to 6 with a constant interval, the lower heat treatment devices are arranged in numbers of 3 to 6 to correspond to each of the 3 to 6 upper heat treatment devices, a heating zone may be defined in one area of ​​the conveyor belt between the upper heat treatment devices and the lower heat treatment devices, the heating zone may be defined in numbers of 3 to 6, and the substrate may include a step of passing through three or more of the heating zones.

[0028] The above heating zone may include a first heating zone, a second heating zone, and a third heating zone, and the first to third heating zones may include first to third upper heat treatment devices and first to third lower heat treatment devices, respectively.

[0029] The first upper heat treatment device discharges air at a temperature of 140°C to 190°C, the first lower heat treatment device discharges air at a temperature of 170°C to 190°C, the second upper heat treatment device discharges air at a temperature of 140°C to 160°C, the second lower heat treatment device discharges air at a temperature of 150°C to 170°C, the third upper heat treatment device discharges air at a temperature of 140°C to 160°C, and the third lower heat treatment device can discharge air at a temperature of 140°C to 160°C.

[0030] The present invention is capable of various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, as well as the methods for achieving them, will become clearer with reference to the embodiments described in detail below, along with the drawings. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various forms.

[0031] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. When describing with reference to the drawings, identical or corresponding components are given the same drawing reference numerals, and redundant descriptions thereof will be omitted.

[0032] In the examples below, the terms first, second, etc. are not used in a limiting sense, but are used for the purpose of distinguishing one component from another.

[0033] In the examples below, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0034] In the examples below, terms such as “include” or “have” mean that a feature or component described in the specification is present, and do not preclude the possibility that one or more other features or components may be added.

[0035] For convenience of explanation, the sizes of components in the drawings may be exaggerated or reduced. For example, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to what is shown.

[0036] In the following examples, the x-axis, y-axis, and z-axis are not limited to three axes on an orthogonal coordinate system, and can be interpreted in a broad sense that includes them. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may also refer to different directions that are not orthogonal to each other.

[0037] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0038] One embodiment of the present invention relates to a heat treatment process system, and another embodiment of the present invention relates to a heat treatment method for a perovskite thin film, which will be described with reference to FIGS. 1 to 6, which schematically illustrate several examples of the heat treatment process system and the heat treatment method for a perovskite thin film.

[0039] FIG. 1 is a drawing schematically illustrating an example of a heat treatment process according to one embodiment of the present invention, and FIG. 2 is a drawing schematically illustrating an example of a heat treatment device used in the heat treatment process of FIG. 1.

[0040] Referring to FIGS. 1 and 2, the heat treatment process may include an upper heat treatment device (10), a lower heat treatment device (20), and a conveyor belt (30) on which a substrate (W) is transported.

[0041] The upper heat treatment device (10) may include a rotating member (100), a rotating blade (200) coupled to one side of the rotating member, a heater (300), and a cover member (400).

[0042] The rotating member (100) may include, for example, a motor, and by rotating a rotating blade (200) coupled to one side of the rotating member, wind can be generated and the flow of air can be controlled. At this time, the rotational speed of the motor may be 600 rpm to 3000 rpm.

[0043] The heater (300) is placed apart from the rotary blade (200) on the side of the air flow direction of the rotary blade (200), and the air flow generated by the rotary blade (200) passes through the heater (300) and the temperature can rise to 140°C to 190°C.

[0044] The cover member (400) can be placed on a surface opposite to the surface on which the rotary blade (200) of the heater (300) is placed.

[0045] For example, the cover member (400) may be formed with a plurality of through holes. These multiple through holes may serve as outlets through which air having passed through the heater (300) and whose temperature has increased is discharged. By forming multiple outlets in the cover member (400), hot air discharged through the upper heat treatment device (10) can be uniformly supplied to a desired location to transfer heat.

[0046] The lower heat treatment device (20) can be arranged to face the upper heat treatment device (10), and its specific configuration can be the same as that of the upper heat treatment device (10) described above, and can be arranged so that the direction of the discharge port is opposite to the direction of the discharge port of the upper heat treatment device (10), i.e., can be arranged to face the upper heat treatment device (10) in the opposite direction.

[0047] Meanwhile, when using the upper heat treatment device (10) and the lower heat treatment device (20) according to the embodiment of the present invention, unlike the conventional hot plate heating method in which heat transfer occurs only from the bottom to the top, heat can be transferred evenly to the upper / lower / left / right front surfaces of the substrate (w) by generating hot air and circulating the hot air.

[0048] A conveyor belt (30) is arranged between an upper heat treatment device (10) and a lower heat treatment device (20) to support and transport one or more substrates (w). At this time, the upper heat treatment device (10) and the lower heat treatment device (20) can supply hot air toward one or more substrates (w) arranged on the conveyor belt (30) to transfer heat. At this time, the conveyor belt (30) can transport one or more substrates (w) at a speed of 25 cm / min to 40 cm / min.

[0049] For example, the conveyor belt (30) may include a mesh shape, and since the conveyor belt (30) has a mesh shape, hot air supplied from the upper and lower portions can be supplied to one or more substrates (w) located on the conveyor belt (30) to transfer heat.

[0050] In an optional embodiment, the substrate (w) may be a single-crystal or polycrystalline silicon wafer, and may include p-type silicon, n-type silicon, or silicon in the form of a Pn junction, and may include any one selected from, but not limited to, borosilicate glass, quartz glass, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polycarbonate (PC), polypropylene (PP), triacetyl cellulose (TAC), or polyether sulfone (PES).

[0051] The substrate (w) according to an embodiment of the present invention may be a silicon wafer in which a recombination layer, a hole transport layer, and a perovskite layer are formed and included on the silicon wafer to form a tandem solar cell.

[0052] Meanwhile, the heat treatment process according to an embodiment of the present invention includes a conveyor belt (30) capable of continuously transporting the substrate (w), thereby enabling a continuous heat treatment process of the substrate (w), and thus mass production of products, for example, solar cells, is possible. In addition, unlike the conventional case where the size of the substrate (w) that can be heat treated is limited by the size of the hot plate, the heat treatment method that transfers heat using hot air supplied from the top and bottom enables heat treatment of a large-area substrate (w) without being limited by the size of the substrate (w).

[0053] Meanwhile, in order to supply hot air to the substrate (w), the motor (100) and the rotary blade (200) arranged on one side of the motor (100) rotate at a rotation speed of 600 rpm to 3000 rpm, and the speed of the hot air supplied to the substrate (w) can be controlled. If the rotation speed of the motor (100) is less than 600 rpm, the amount of hot air supplied is small compared to the speed of the substrate (w) being transported by the conveyor belt, so that sufficient heat transfer to the substrate (w) is difficult, and there is a problem that the substrate (w) is heat-treated at a temperature lower than the desired temperature, and if the rotation speed is greater than 3000 rpm, the amount of hot air supplied is large compared to the speed of the substrate (w) being transported by the conveyor belt, so that excessive heat is transferred to the substrate (w), and there is a problem that the substrate (w) may be heat-treated at a temperature higher than the desired temperature.

[0054] Figure 3 is a schematic diagram illustrating another example of the heat treatment process of Figure 1.

[0055] Referring to Fig. 3, a plurality of upper heat treatment devices (10) may be arranged at regular intervals, and a plurality of lower heat treatment devices (20) may be arranged to correspond to each of the plurality of upper heat treatment devices (10). At this time, a heating zone may be defined in an area where the lower heat treatment devices (20) are arranged to correspond to the upper heat treatment devices (10).

[0056] As an optional embodiment, three or more upper heat treatment devices (10) and lower heat treatment devices (20) may be arranged at corresponding positions with a constant interval therebetween, and as a specific example, six upper heat treatment devices (10) and lower heat treatment devices (20) may be arranged at corresponding positions with a constant interval therebetween. Accordingly, first to sixth heating zones may be defined as heating zones.

[0057] For example, the first and second heating zones (Zone 1, Zone 2) may be sections for rapidly increasing the temperature of the substrate (w) to 140°C to 160°C as an initial heat treatment section, and the third to sixth heating zones (Zone 3, Zone 4, Zone 5, Zone 6) may be sections for stabilizing the temperature of the substrate (w) to 145°C to 155°C.

[0058] Each heating zone defined in this way may have different temperatures of air discharged from the upper heat treatment device (10) and the lower heat treatment device (20) for each heating zone, and thus the heat treatment temperature may differ for each heating zone. Furthermore, even for the same heating zone, the temperatures of air supplied from the upper heat treatment device and the lower heat treatment device may differ from each other.

[0059] As a specific example, the first upper heat treatment device of the first heating zone (1 Zone) discharges air at a temperature of 140°C to 190°C, the first lower heat treatment device discharges air at a temperature of 170°C to 190°C, the second upper heat treatment device of the second heating zone (2 Zone) discharges air at a temperature of 140°C to 160°C, the second lower heat treatment device discharges air at a temperature of 150°C to 170°C, and the third to sixth upper heat treatment devices of the third to sixth heating zones (3 Zone, 4 Zone, 5 Zone, 6 Zone) discharge air at a temperature of 140°C to 160°C, and the third to sixth lower heat treatment devices discharge air at a temperature of 140°C to 160°C.

[0060] As an optional embodiment, the heat treatment process according to an embodiment of the present invention can be applied to the heat treatment step of a perovskite thin film.

[0061] Meanwhile, the initial heat treatment (~1 min) is a very important factor for the perovskite thin film, and when the heat treatment is performed through the first to sixth heating zones of the heat treatment process according to the embodiment of the present invention, by controlling the upper and lower temperatures of the first heating zone (1 Zone) and the second heating zone (2 Zone), which are the initial heat treatment sections, differently, a uniform perovskite thin film can be formed in a downward manner, and by setting the temperature of the lower heat treatment device in the initial heat treatment section (1 Zone, 2 Zone) and the Heat Blower Speed ​​of the rotating blade (200) high, the temperature of the heat transferred to the substrate (w) can be quickly increased.

[0062] In this way, through rapid heat transfer and a gradient of heat treatment temperature in the initial heat treatment section (Zone 1, Zone 2), the crystallinity of the perovskite thin film can be improved, and as a result, a high-quality perovskite thin film can be formed.

[0063] The following description specifically explains a method for heat treatment of a perovskite thin film using a heat treatment system according to an embodiment of the present invention.

[0064] In general, a method for manufacturing a perovskite thin film may include, but is not limited to, a step of manufacturing a perovskite mixture, a step of coating the perovskite mixture on a substrate, a step of drying the substrate coated with the perovskite mixture, and a step of heat-treating the dried substrate, and may include all manufacturing methods used to manufacture a perovskite thin film.

[0065] The perovskite mixture may include a general perovskite material applied to the light absorption layer of a solar cell, and the perovskite having a three-dimensional crystal structure may include a perovskite material that absorbs light at a wavelength of 300 to 800 nm. For example, the perovskite mixture may include a compound represented by the following chemical formula 1.

[0066] [Chemical Formula 1]

[0067] [A][B][X]3

[0068] In the above chemical formula 1, A is a monovalent organic cation, a monovalent metal cation, or a monovalent cation mixed therewith, B is a divalent metal cation, and X is at least one anion.

[0069] In the step of coating the perovskite mixture on the substrate, the coating process may include any one of blade coating, slot die coating, bar coating, inkjet coating, or spray coating.

[0070] The step of drying the substrate coated with the perovskite mixture can be performed together with the coating process, or can be performed as a separate process after the coating process is completed. Preferable examples of drying methods include drying using an inert gas such as N2 or Ar, or drying using an air knife. Through drying, the solvent in the coating agent can be evaporated, and a wet-thin film including the perovskite crystallized in the intermediate phase is formed.

[0071] After the perovskite mixture is coated, the step of heat treating the dried substrate can be performed by the heat treatment process system described above.

[0072] The following description relates to a method for heat treating a perovskite thin film using a heat treatment process system.

[0073] A method for heat treating a perovskite thin film may include a step (s100) of placing a substrate on a conveyor belt and a step (s200) of passing the substrate through a heating zone defined between an upper heat treatment device and a lower heat treatment device via the conveyor belt.

[0074] In the step (s100) of placing a substrate (w) on a conveyor belt (30), one or more dried substrates are placed on the conveyor belt (30), and the conveyor belt (30) can transport the substrates at a speed of 25 cm / min to 40 cm / min while supporting the substrates.

[0075] In a step (s200) in which a substrate passes through a heating zone defined between an upper heat treatment device and a lower heat treatment device via a conveyor belt, one or more substrates supported on a conveyor belt (30) and transported can be heat treated by passing through a heating zone defined by a plurality of heat treatment devices (10, 20) arranged at regular intervals above and below the conveyor belt (30).

[0076] Meanwhile, the method for heat treating a perovskite thin film may further include a step (s300) in which the substrate passes through the three or more heating zones, and in the step (s300) in which the substrate passes through the three or more heating zones, the heating zones may be defined as first to sixth heating zones, and the first upper heat treatment device of the first heating zone (1 Zone) discharges air of 140° C. to 190° C. toward one or more dried substrates arranged and transported on a conveyor belt (30), the first lower heat treatment device discharges air of 170° C. to 190° C., the second upper heat treatment device of the second heating zone (2 Zone) discharges air of 140° C. to 160° C., the second lower heat treatment device discharges air of 150° C. to 170° C., and the third to sixth heating zones (3 Zone, 4 Zone, 5 Zone, 6 Zone) The upper heat treatment device can discharge air at a temperature of 140°C to 160°C, and the third to sixth lower heat treatment devices can discharge air at a temperature of 140°C to 160°C.

[0077] Meanwhile, the first to second heating zones (Zone 1, Zone 2) may be initial heat treatment sections for rapidly increasing the temperature of the substrate (w) to 140°C to 160°C, and the third to sixth heating zones (Zone 3, Zone 4, Zone 5, Zone 6) may be sections for stabilizing the temperature of the substrate (w) to 145°C to 155°C.

[0078] Accordingly, the step (s300) in which the substrate passes through the three or more heating zones may be performed at the same step as the step (s200) in which the substrate passes through the heating zones defined between the upper heat treatment device and the lower heat treatment device via the conveyor belt, and the substrate may pass through at least the first to third heating zones (Zone 1, Zone 2, Zone 3).

[0079] At this time, the heat treatment device (10, 20) can control the speed of the hot air supplied to the dried substrate by rotating the motor (100) and the rotary blade (200) arranged on one side of the motor (100) at 600 rpm to 3000 rpm to supply hot air to the dried substrate.

[0080]

[0081] Example 1

[0082] In order to heat-treat the substrate after coating and drying the perovskite mixture, the substrate was transported at a speed of 32 cm / min through a conveyor belt (30), the first upper heat treatment device of the first heating zone (1 Zone) supplied hot air of 145°C to the substrate, and the first lower heat treatment device supplied hot air of 180°C to the substrate, the second upper heat treatment device of the second heating zone (2 Zone) supplied hot air of 145°C to the substrate, and the second lower heat treatment device supplied hot air of 165°C to the substrate, and the third to sixth upper heat treatment devices and the third to sixth lower heat treatment devices of the third to sixth heating zones (3 Zone, 4 Zone, 5 Zone, 6 Zone) supplied hot air of 153°C to the substrate. At this time, the rotary blades (200) of the first to sixth upper heat treatment devices and the first to sixth lower heat treatment devices were rotated at 2500 rpm.

[0083]

[0084] Example 2

[0085] Heat treatment was performed in the same manner as in Example 1, except that the rotary blades (200) of the first to sixth upper heat treatment devices and the first to sixth lower heat treatment devices were rotated at 1500 rpm.

[0086]

[0087] Comparative Example 1

[0088] To heat-treat the substrate after coating and drying the perovskite mixture, the substrate was heat-treated using a hotplate set to 150°C.

[0089] Figure 5 is a graph of temperature rise over time.

[0090] Referring to Fig. 5, the time taken for the substrate temperature to rise to 150°C can be confirmed. At this time, it can be confirmed that Example 1 took 23 seconds for the substrate temperature to rise to 150°C, Example 2 took 41 seconds for the substrate temperature to rise to 150°C, and Comparative Example 1 took 28 seconds for the substrate temperature to rise to 150°C. Meanwhile, the initial heat treatment temperature is an important factor in determining the quality of the perovskite thin film, and it can be confirmed that Example 1 is more suitable for the heat treatment of the perovskite thin film because it raises the substrate temperature at a faster rate compared to the conventional Comparative Example 1.

[0091] Figures 6 and 7 are XRD graphs of perovskite thin films.

[0092] Referring to FIGS. 6 and 7, FIG. 6 is a graph analyzing the surface of a perovskite thin film heat-treated in Example 1 and Comparative Example 1 using XRD, and FIG. 7 is a graph analyzing the bulk of a perovskite thin film heat-treated in Example 1 and Comparative Example 1 using XRD.

[0093] Referring to the graph of FIG. 6, it can be confirmed that the same perovskite crystals were formed on the surface of the perovskite thin film as peaks were formed at the same locations in both Example 1 and Comparative Example 1, and when the intensity of the peak indicated by C is compared, it can be confirmed that there is no significant difference in the crystallinity of the perovskite crystals formed on the surface of the perovskite thin film as Example 1 is 10069.44863 (au) and Comparative Example 1 is 10401.94887 (au).

[0094] Referring to the graph of Fig. 7, it can be confirmed that the same perovskite crystals were formed in the bulk of the perovskite thin film as peaks were formed at the same locations in both Example 1 and Comparative Example 1, and when the intensity of the peak indicated by D is compared, it can be confirmed that there is no significant difference in the crystallinity of the perovskite crystals formed in the bulk of the perovskite thin film as Example 1 is 3524.78659 (au) and Comparative Example 1 is 3629.48836 (au).

[0095] Experiment 1 Zone(℃) Zone 2 Zone(℃) Zone 3-6 Rotating blade speed(rpm) Eff.[%] Voc[V] Jsc[mA / cm2] FF[%] Upper Lower Upper Lower Upper Lower -20.101.7618.469 Comparative example 1150℃ Example 1145180145165153153250021.051.8418.3571

[0096] Table 1 is a table comparing the efficiency of a heat treatment process according to an embodiment of the present invention and a hotplate-based heat treatment method. Referring to Table 1, it can be confirmed that the efficiency of Example 1 increased by about 1% compared to Comparative Example 1, and it can also be confirmed that the open circuit voltage (Voc) and fill factor (FF) were improved. As a result, by heat-treating a perovskite thin film using a heat treatment process according to an embodiment of the present invention, the crystallinity of the perovskite thin film can be improved through rapid heat transfer and a gradient of heat treatment temperature in the initial heat treatment section, and as a result, a high-quality perovskite thin film can be formed, which can improve the efficiency of the solar cell. In addition, unlike the case where the size of the heat-treatable substrate was limited by the size of the hot plate, the heat treatment method that transfers heat using hot air supplied from the top and bottom enables heat treatment of a large-area substrate without being limited by the size of the substrate. In addition, by transporting one or more substrates using a conveyor belt, a continuous heat treatment process is possible, enabling mass production of perovskite thin films. The above description of the present invention is for illustrative purposes, and those skilled in the art to which the present invention pertains will understand that the present invention can be easily modified into other specific forms without changing the technical spirit or essential characteristics of the present invention. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single component may be implemented in a distributed manner, and likewise, components described as distributed may be implemented in a combined manner. The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. Perform a heat treatment process on one or more substrates, Upper heat treatment device; A lower heat treatment device spaced apart from and facing the upper heat treatment device; and A heat treatment process system including a conveyor belt arranged between the upper heat treatment device and the lower heat treatment device and arranged to transport the substrate while supporting it.

2. In paragraph 1, The above heat treatment device, rotating member; A rotary blade coupled to one side of the above rotary member to control the flow of air; and A heat treatment process system comprising a heater disposed in the direction of the air flow of the rotating blade.

3. In paragraph 2, The above heat treatment device further includes a cover member having an air discharge port formed therein; A heat treatment process system in which air flowing through the above heater is discharged through the above outlet.

4. In paragraph 1, A heat treatment process system, comprising a plurality of upper heat treatment devices arranged at intervals spaced apart from each other.

5. In paragraph 4, A heat treatment process system, wherein the lower heat treatment device is arranged in multiple numbers to correspond to each of the plurality of upper heat treatment devices.

6. In paragraph 4, The above upper heat treatment devices are arranged in three or more units with a gap between them, The lower heat treatment devices are arranged in three or more numbers to correspond to each of the three or more upper heat treatment devices, A heat treatment process system, wherein a heating zone can be defined in an area between the upper heat treatment device and the lower heat treatment device, and wherein three or more heating zones are defined, and the temperature of air supplied from the upper heat treatment device and the lower heat treatment device is different for each heating zone.

7. In paragraph 1, The above conveyor belt is a heat treatment process system including a mesh shape.

8. A heat treatment method for forming a perovskite thin film, An upper heat treatment device, a lower heat treatment device positioned opposite to the upper heat treatment device, and A heat treatment process system including a conveyor belt disposed between the upper heat treatment device and the lower heat treatment device is used, a step of placing a substrate on the conveyor belt; and A method for heat treatment of a perovskite thin film, comprising: a step of passing the substrate through a heating zone defined between the upper heat treatment device and the lower heat treatment device via the conveyor belt; 9. In paragraph 8, A method for heat treatment of a perovskite thin film, wherein the substrate comprises a perovskite mixture coated on at least one surface.

10. In paragraph 8, The above upper heat treatment devices are arranged in three or more units with a gap between them, The above lower heat treatment devices are arranged in three or more units to correspond to each of the three or more upper heat treatment devices arranged, A heating zone may be defined in one area of ​​the conveyor belt between the upper heat treatment device and the lower heat treatment device, and three or more heating zones are defined. The substrate comprises a step of passing through the three or more heating zones, Heat treatment method for perovskite thin films.

11. In paragraph 10, The above heating zone includes a first heating zone, a second heating zone and a third heating zone, A method for heat treatment of a perovskite thin film, wherein the first to third heating zones each include first to third upper heat treatment devices and first to third lower heat treatment devices.

12. In paragraph 11, The first upper heat treatment device discharges air at 140°C to 190°C, The first lower heat treatment device discharges air at 170°C to 190°C, The second upper heat treatment device discharges air at 140°C to 160°C, The second lower heat treatment device discharges air at 150°C to 170°C, The third upper heat treatment device discharges air at 140°C to 160°C, A method for heat treatment of a perovskite thin film, wherein the third lower heat treatment device discharges air at 140°C to 160°C.

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