阅读说明：本技术 一种太阳能电池的制备方法及太阳能电池 (Preparation method of solar cell and solar cell ) 是由 曾鑫林 张晓攀 单伟 何胜 徐伟智 于 2019-10-09 设计创作，主要内容包括：本申请公开了一种太阳能电池的制备方法,通过将太阳能电池前置物置于镀膜腔体内加热；将所述镀膜腔体内抽真空；向所述镀膜腔体内输入氨气与硅烷,通过射频电离法在所述太阳能电池前置物表面沉积氮化硅薄膜；其中,射频发生器的占空比为1:5至1:8,包括端点值；经过预设的沉积时间后,将所述镀膜腔体内先抽真空,再充入惰性气体；在所述镀膜腔体内对沉积过所述氮化硅薄膜的太阳能电池前置物进行退火；在经过退火处理的所述太阳能电池前置物表面设置电极,得到所述太阳能电池。本申请降低氮化硅薄膜的致密性,使电极浆料能更顺利地穿透所述氮化硅薄膜与硅形成良好的欧姆接触,提高电池的发电效率。本申请还提供了一种具有上述有益效果的太阳能电池。(The application discloses a preparation method of a solar cell, which comprises the steps of placing a solar cell front object in a film coating cavity for heating; vacuumizing the coating cavity; inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive; after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas; annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity; and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell. The compactness of the silicon nitride film is reduced, the electrode slurry can smoothly penetrate through the silicon nitride film to form good ohmic contact with silicon, and the power generation efficiency of the battery is improved. The application also provides a solar cell with the beneficial effects.)

1. A method for manufacturing a solar cell, comprising:

placing the solar cell front object in a film coating cavity for heating;

vacuumizing the coating cavity;

inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive;

after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas;

annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity;

and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell.

2. The method of claim 1, further comprising, prior to depositing the silicon nitride film on the solar cell precursor surface:

and inputting ammonia gas into the coating cavity, and pre-cleaning the surface of the solar cell front object.

3. The method according to claim 2, wherein the pre-cleaning is performed by the rf generator to pre-clean the surface of the solar cell, and the duty ratio of the rf generator is in a range from 1:5 to 1:8, inclusive.

4. The method of claim 3, wherein the pre-cleaning is performed for a time in a range of 5 seconds to 30 seconds, inclusive.

5. The method according to claim 1, wherein the depositing of the silicon nitride film on the front object surface of the solar cell comprises a pre-heating stage, a first deposition stage and a second deposition stage;

the heating temperature range of the preheating stage is 430-460 degrees celsius, and the duration range of the preheating stage is 30-120 seconds, inclusive.

6. The method of claim 5, wherein the first deposition phase has an ammonia gas input rate in a range of 1000 standard milliliters per minute to 15000 standard milliliters per minute, a silane input rate in a range of 200 standard milliliters per minute to 1500 standard milliliters per minute, and a radio frequency generator power in a range of 5000 watts to 15000 watts, inclusive.

7. The method of claim 5, wherein the ammonia gas input rate for the second deposition phase ranges from 1000 standard milliliters per minute to 15000 standard milliliters per minute, the silane input rate ranges from 400 standard milliliters per minute to 1200 standard milliliters per minute, and the RF generator power ranges from 5000 watts to 12000 watts, inclusive.

8. The method according to any of claims 5 to 7, wherein the total length of time of the first deposition phase and the second deposition phase ranges from 600 seconds to 750 seconds.

9. A solar cell obtained by the method for manufacturing a solar cell according to any one of claims 1 to 8.

10. The solar cell of claim 9, wherein the silicon nitride layer of the solar cell has a thickness in a range from 50 nanometers to 250 nanometers, inclusive.

Technical Field

The application relates to the field of photovoltaic cells, in particular to a solar cell and a preparation method thereof.

Background

With the continuous development of photovoltaic power generation technology, various novel efficient solar cells are developed in a large number. Particularly, with the coming of the flat-price internet-surfing era, how to manufacture more efficient and stable batteries becomes a primary task in the photovoltaic industry.

The pull-off force is the connection strength of a cell and a solder strip and is a particularly important index of the solar cell, but the pull-off force in the prior art is always hidden, and the method for improving the pull-off force is to change the design of a screen printing plate by changing the slurry proportion of an electrode so that a sintered grid line can be better connected with other structures of the solar cell. However, changing the electrode material causes other new problems, such as low efficiency, increased wet weight, increased cost, smaller sintering window, etc. Therefore, how to improve the pull-out force of the solar cell without increasing the wet weight of the slurry and increasing the cost is a primary problem to be solved urgently by those skilled in the art.

Content of application

The application aims to provide a solar cell and a preparation method thereof, so as to solve the problem of poor pull-out force in the prior art.

In order to solve the above technical problem, the present application provides a method for manufacturing a solar cell, including:

placing the solar cell front object in a film coating cavity for heating;

vacuumizing the coating cavity;

inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive;

after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas;

annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity;

and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell.

Optionally, in the method for manufacturing a solar cell, before depositing the silicon nitride film on the surface of the solar cell front object, the method further includes:

and inputting ammonia gas into the coating cavity, and pre-cleaning the surface of the solar cell front object.

Optionally, in the method for manufacturing a solar cell, the pre-cleaning is performed on the surface of the solar cell by using the radio frequency generator, and the duty ratio of the radio frequency generator ranges from 1:5 to 1:8, inclusive.

Optionally, in the method for manufacturing a solar cell, the pre-cleaning time is in a range of 5 seconds to 30 seconds, inclusive.

Optionally, in the method for manufacturing a solar cell, depositing a silicon nitride film on the surface of the solar cell front object specifically includes a preheating stage, a first deposition stage, and a second deposition stage;

the heating temperature range of the preheating stage is 430-460 degrees celsius, and the duration range of the preheating stage is 30-120 seconds, inclusive.

Optionally, in the method for manufacturing a solar cell, the ammonia gas input rate in the first deposition stage ranges from 1000 standard milliliters per minute to 15000 standard milliliters per minute, the silane input rate ranges from 200 standard milliliters per minute to 1500 standard milliliters per minute, and the power of the rf generator ranges from 5000 watts to 15000 watts, inclusive.

Optionally, in the method for manufacturing a solar cell, the ammonia gas input rate in the second deposition stage ranges from 1000 standard milliliters per minute to 15000 standard milliliters per minute, the silane input rate ranges from 400 standard milliliters per minute to 1200 standard milliliters per minute, and the power of the rf generator ranges from 5000 watts to 12000 watts, inclusive.

Optionally, in the method for manufacturing a solar cell, a total length of time of the first deposition phase and the second deposition phase ranges from 600 seconds to 750 seconds.

The application also provides a solar cell, which is obtained by the preparation method of the solar cell.

Optionally, in the solar cell, a thickness of the silicon nitride layer of the solar cell ranges from 50 nm to 250 nm, inclusive. .

According to the preparation method of the solar cell, the solar cell front object is placed in the film coating cavity to be heated; vacuumizing the coating cavity; inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive; after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas; annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity; and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell. It should be noted that, in practical production, the solder strip is connected to the grid line of the solar cell, and the connection strength between the solder strip and the grid line is much higher than that between the grid line and the cell, so to improve the pull-off force, the connection strength between the grid line and the cell should be considered. This application is through changing radio frequency generator's duty cycle during the sedimentary deposit on solar wafer surface reduces the compactness of sedimentary deposit (above-mentioned silicon nitride film promptly), makes electrode slurry can more pierce through silicon nitride film forms good ohm mould contact with silicon, promotes greatly and draws the power of taking off, enlarges the thick liquids window, reduces thick liquids wet weight, improves the generating efficiency of battery. The application also provides a solar cell with the beneficial effects.

Drawings

For a clearer explanation of the embodiments or technical solutions of the prior art of the present application, the drawings needed for the description of the embodiments or prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic flow chart of an embodiment of a method for manufacturing a solar cell provided herein;

fig. 2 is a schematic flow chart of another embodiment of a method for manufacturing a solar cell provided herein;

fig. 3 is a schematic flow chart of another embodiment of a method for manufacturing a solar cell provided by the present application.

Detailed Description

In order that those skilled in the art will better understand the disclosure, the following detailed description will be given with reference to the accompanying drawings. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The core of the present application is to provide a method for manufacturing a solar cell, wherein a schematic flow diagram of one embodiment is shown in fig. 1, which is referred to as a first embodiment, and the method includes:

step S101: and placing the solar cell front object in a film coating cavity for heating.

The temperature of the heating ranges from 400 degrees celsius to 550 degrees celsius, inclusive, such as any of 400.0 degrees celsius, 500.0 degrees celsius, or 550.0 degrees celsius. The heating process is in a nitrogen atmosphere with a flow rate of nitrogen ranging from 5000sccm (standard milliliters per minute) to 10000sccm, including extended point values such as any of 5000.0sccm, 6325.0sccm, or 10000.0 sccm. The heating period ranges from 640 seconds to 1100 seconds, inclusive, such as 640.0 seconds, 853.0 seconds, or 1100.0 seconds.

Step S102: and vacuumizing the coating cavity.

Controlling the temperature at 400-550 ℃, pumping air to the furnace tube by using a vacuum pump, keeping the pressure at 20-100mTorr within 120-300s, maintaining the pressure at 30-120s, observing whether the pressure exceeds 100mTorr, and if not, carrying out the next step.

Step S103: inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive.

Step S104: and after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas.

The temperature of the vacuum pumping is controlled to be 430-560 ℃, the vacuum pump is used for pumping air to the furnace tube, the pressure reaches 10-50mTorr within 120-300s, and the pressure is maintained for 60 s.

The MFC for each reaction gas was purged with nitrogen at a flow rate in the range of 5000-15000 sccm.

Step S105: and annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity.

The annealing temperature ranges from 500 ℃ to 550 ℃; the duration is 120 seconds to 480 seconds, inclusive.

Step S106: and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell.

And (4) before the finished product is taken out of the furnace, keeping the temperature of the finished product in an environment of 400-500 ℃ for 100-400 seconds, and then taking out.

It should be noted that the solar cell precursor is a semi-finished product of a solar cell piece without depositing a silicon nitride film on the outermost layer and arranging an electrode, the invention of the application is that the silicon nitride film is thinned to enable the electrode slurry to be in close contact with other structures, and the other film layer structures of the cell piece do not obstruct the innovation point of the application, so the solar cell precursor is collectively called as the solar cell precursor.

According to the preparation method of the solar cell, the solar cell front object is placed in the film coating cavity to be heated; vacuumizing the coating cavity; inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive; after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas; annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity; and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell. It should be noted that, in practical production, the solder strip is connected to the grid line of the solar cell, and the connection strength between the solder strip and the grid line is much higher than that between the grid line and the cell, so to improve the pull-off force, the connection strength between the grid line and the cell should be considered. This application is through changing radio frequency generator's duty cycle during the sedimentary deposit on solar wafer surface reduces the compactness of sedimentary deposit (above-mentioned silicon nitride film promptly), makes electrode slurry can more pierce through silicon nitride film forms good ohm mould contact with silicon, promotes greatly and draws the power of taking off, enlarges the thick liquids window, reduces thick liquids wet weight, improves the generating efficiency of battery.

On the basis of the first specific embodiment, a method for manufacturing a solar cell is further improved to obtain a second specific embodiment, a schematic flow diagram of which is shown in fig. 2, and the method includes:

step S201: and placing the solar cell front object in a film coating cavity for heating.

Step S202: and vacuumizing the coating cavity.

Step S203: and inputting ammonia gas into the coating cavity, and pre-cleaning the surface of the solar cell front object.

Step S204: inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive.

Step S205: and after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas.

Step S206: and annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity.

Step S207: and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell.

The difference between the specific embodiment of the present invention and the above specific embodiment is that, in the specific embodiment, before depositing the silicon nitride film, the surface of the solar cell front object is pre-cleaned, and the remaining steps are the same as those in the above specific embodiment, and are not described herein again.

The pre-cleaning is to pre-clean the surface of the solar cell through the radio frequency generator, and the duty ratio of the radio frequency generator is in a range of 1:5 to 1:8, including any one of 1:5.0, 1:7.0 or 1: 8.0. The pre-wash time ranges from 5 seconds to 30 seconds, inclusive, such as any of 5.0 seconds, 15.0 seconds, or 30.0 seconds.

According to the specific embodiment, the surface of the silicon wafer is pre-cleaned by ammonia gas before deposition, so that the effect of leveling the surface can be achieved while impurities are removed, and the silicon nitride film to be deposited next is more level and uniform in texture.

On the basis of the second embodiment, the parameters in the process of depositing the silicon nitride film are further defined to obtain a third embodiment, a schematic flow diagram of which is shown in fig. 3, and includes:

step S301: and placing the solar cell front object in a film coating cavity for heating.

Step S302: and vacuumizing the coating cavity.

Step S303: and inputting ammonia gas into the coating cavity, and pre-cleaning the surface of the solar cell front object.

Step S304: inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive;

the method comprises the following steps of depositing a silicon nitride film on the surface of the solar cell front object, wherein the silicon nitride film specifically comprises a preheating stage, a first deposition stage and a second deposition stage;

the heating temperature range of the preheating stage is 430-460 degrees celsius, and the duration range of the preheating stage is 30-120 seconds, inclusive.

Step S305: and after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas.

Step S306: and annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity.

Step S307: and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell.

The difference between the specific embodiment and the above specific embodiment is that the parameters in the deposition process are defined in the specific embodiment, and the rest of the steps are the same as those in the above specific embodiment, and are not described herein again.

It should be noted that the preheating phase, the first deposition phase and the second deposition phase are not present in this embodiment, but are limited in this embodiment. Still further, the first deposition phase has an ammonia gas input rate in a range of 1000 standard milliliters per minute to 15000 standard milliliters per minute, a silane input rate in a range of 200 standard milliliters per minute to 1500 standard milliliters per minute, and a radio frequency generator power in a range of 5000 watts to 15000 watts, inclusive.

The ammonia gas input rate for the second deposition phase ranges from 1000 standard milliliters per minute to 15000 standard milliliters per minute, the silane input rate ranges from 400 standard milliliters per minute to 1200 standard milliliters per minute, and the power of the radio frequency generator ranges from 5000 watts to 12000 watts, inclusive.

The total length of time of the first deposition phase and the second deposition phase ranges from 600 seconds to 750 seconds, wherein the duration of the first deposition phase ranges from 50 seconds to 200 seconds, and the duration of the second deposition phase ranges from 150 seconds to 600 seconds, inclusive. The data are ideal parameter ranges with good effects obtained through theoretical calculation and actual inspection, and can be adjusted according to different actual requirements.

The application also provides a solar cell, which is obtained by the preparation method of the solar cell. According to the preparation method of the solar cell, the solar cell front object is placed in the film coating cavity to be heated; vacuumizing the coating cavity; inputting ammonia gas and silane into the coating cavity, and depositing a silicon nitride film on the surface of the solar cell front object by a radio frequency ionization method; wherein the duty cycle of the radio frequency generator is 1:5 to 1:8, inclusive; after the preset deposition time, vacuumizing the coating cavity, and then filling inert gas; annealing the solar cell precursor deposited with the silicon nitride film in the coating cavity; and arranging an electrode on the surface of the annealed solar cell front object to obtain the solar cell. It should be noted that, in practical production, the solder strip is connected to the grid line of the solar cell, and the connection strength between the solder strip and the grid line is much higher than that between the grid line and the cell, so to improve the pull-off force, the connection strength between the grid line and the cell should be considered. This application is through changing radio frequency generator's duty cycle during the sedimentary deposit on solar wafer surface reduces the compactness of sedimentary deposit (above-mentioned silicon nitride film promptly), makes electrode slurry can more pierce through silicon nitride film forms good ohm mould contact with silicon, promotes greatly and draws the power of taking off, enlarges the thick liquids window, reduces thick liquids wet weight, improves the generating efficiency of battery.

Still further, the silicon nitride layer of the solar cell has a thickness in a range from 50 nanometers to 250 nanometers, inclusive, such as any of 50.0 nanometers, 100.2 nanometers, or 250.0 nanometers.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

It is to be noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The method for manufacturing the solar cell and the solar cell provided by the present application are described in detail above. The principles and embodiments of the present application are explained herein using specific examples, which are provided only to help understand the method and the core idea of the present application. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present application without departing from the principle of the present application, and such improvements and modifications also fall within the scope of the claims of the present application.