CN106920863B - A kind of back surface processing method of antimony selenide thin-film solar cells - Google Patents

Abstract

The invention belongs to the field of preparation of thin-film solar cells, and specifically discloses a method for treating the back surface of an antimony selenide thin-film solar cell. The method uses a liquid containing carbon disulfide to contact the surface of an antimony selenide thin-film layer in an antimony selenide thin-film solar cell. , and the surface of the treated antimony selenide thin film layer is used as the back surface of the antimony selenide thin film solar cell. The present invention effectively reduces the back contact potential barrier of the antimony selenide thin film solar cell by improving the back surface of the antimony selenide thin film layer in the antimony selenide thin film solar cell, thereby achieving the effect of improving the fill factor of the device, and further improving the Photoelectric conversion efficiency of antimony selenide thin film solar cells.

Description

A kind of back surface treatment method of antimony selenide thin film solar cell

technical field

The invention belongs to the field of photoelectric materials and thin-film solar cell preparation, and in particular relates to a method for processing the back surface of an antimony selenide thin film to improve the performance of an antimony selenide thin film solar cell device.

Background technique

Antimony selenide (Sb ₂ Se ₃ ) belongs to group V-VI band compound semiconductors. Its forbidden band width is about 1.2eV, which is just in the band gap range of ideal solar cells, and has a large absorption coefficient and high carrier mobility. , rich storage capacity and no pollution to the environment, so it has attracted the attention of researchers as a new thin-film solar cell material in recent years.

The photoelectric conversion efficiency of the solar cell is PCE=Voc*Jsc*FF, where FF is the fill factor of the solar cell, which is one of the key parameters affecting the photoelectric conversion efficiency of the solar cell. The method mentioned in the invention can reduce the back contact potential barrier of the antimony selenide thin film solar cell, so as to achieve the purpose of increasing the filling factor of the device, thereby improving the photoelectric conversion efficiency of the device.

Contents of the invention

For above improvement needs of prior art, the object of the present invention is to provide a kind of back surface treatment method of antimony selenide thin film solar cell, wherein by the back surface of antimony selenide thin film layer in the antimony selenide thin film solar cell (that is, The antimony selenide thin film surface away from the light-receiving surface of the solar cell) is improved, which effectively reduces the back contact barrier of the antimony selenide thin film solar cell, achieves the effect of improving the fill factor of the device, and then improves the antimony selenide thin film solar energy. The photoelectric conversion efficiency of the battery.

In order to achieve the above object, according to one aspect of the present invention, a kind of back surface treatment method of antimony selenide thin film solar cell is provided, it is characterized in that, the method uses the liquid contact treatment that contains carbon disulfide to treat selenization in antimony selenide thin film solar cell The surface of the antimony thin film layer, and the surface of the treated antimony selenide thin film layer is used as the back surface of the antimony selenide thin film solar cell.

As a further preference of the present invention, the use of the liquid containing carbon disulfide to contact the surface of the antimony selenide thin film layer is to add the liquid containing carbon disulfide dropwise on the surface of the antimony selenide thin film layer, and let it stand for a period of treatment. After a period of time, the carbon disulfide-containing liquid is removed.

As a further preference of the present invention, the removal of the liquid containing carbon disulfide is done by drying with a homogenizer, the homogenizer preferably adopts 1000-3000 revolutions per minute, and the drying time is 30-50s.

As a further preference of the present invention, after removing the liquid containing carbon disulfide, also use deionized water to clean the surface of the antimony selenide thin film layer, and the deionized water is also to be dried by using a homogenizer, and the homogenizer The machine preferably adopts 1000-3000 revolutions per minute, and the drying time is 30-50s.

As a further preference of the present invention, the contact treatment of the surface of the antimony selenide thin film layer with a liquid containing carbon disulfide is carried out at 20°C to 30°C.

As a further preference of the present invention, the liquid containing carbon disulfide is pure carbon disulfide liquid, and the time for the pure carbon disulfide liquid to stand in contact with the antimony selenide thin film layer is 10s-30s.

As a further preference of the present invention, the liquid containing carbon disulfide is a carbon disulfide solution, the volume percentage of the solute carbon disulfide in the carbon disulfide solution is 50%-100%, and the solvent is an organic solvent; the carbon disulfide solution is left standing to contact the antimony selenide film The layering time is 10s-10min; preferably, the organic solvent is at least one of ethanol and ether.

According to another aspect of the present invention, a kind of preparation method of antimony selenide thin-film solar cell is provided, it is characterized in that, comprises the following steps:

Using transparent conductive glass as a substrate, depositing an n-type semiconductor buffer layer on the substrate; then, preparing an antimony selenide film layer on the n-type semiconductor buffer layer; then, using a liquid containing carbon disulfide to contact the antimony selenide the surface of the thin film layer; then, preparing an electrode on the surface of the treated antimony selenide thin film layer, thereby forming an antimony selenide thin film solar cell.

As a further preferred embodiment of the present invention, the n-type semiconductor buffer layer is cadmium sulfide, zinc oxide or titanium dioxide.

As a further preference of the present invention, the transparent conductive glass is ITO or FTO.

Through the above technical scheme conceived by the present invention, compared with the prior art, since the surface of the antimony selenide thin film layer in the antimony selenide thin film solar cell is treated with a liquid containing carbon disulfide, and the treated antimony selenide thin film The surface of the layer is used as the back surface of the antimony selenide thin film solar cell, which can reduce the back contact barrier of the antimony selenide thin film solar cell, improve the fill factor of the device, and thereby improve the photoelectric conversion efficiency of the antimony selenide thin film solar cell device.

The present invention finds in the process of processing the back surface of the antimony selenide film that some solids will float on the liquid surface. It is guessed that carbon disulfide may dissolve the simple selenium on the back surface of the antimony selenide film to a certain extent, and it is precisely because of these selenium The elimination of elemental substances and the removal of floating substances on the surface reduces the back contact barrier.

Description of drawings

Fig. 1 is the filling factor statistical diagram of the FTO/ZnO/Sb2Se3/Au solar cell device obtained after repeated repetitions of Example 3 of the present invention;

Fig. 2 is the series resistance and the parallel resistance statistical diagram of the FTO/ZnO/Sb2Se3/Au solar cell device obtained after repeated repetitions of Example 3 of the present invention; wherein, Fig. 2a corresponds to the series resistance, and Fig. 2b corresponds to the parallel resistance:

Fig. 3 is the X-ray photoelectron spectrum (XPS) of the antimony selenide thin film solar cell that the antimony selenide film back surface that the carbon disulfide treatment that the embodiment of the present invention obtains 3 obtains and comparative example 1 does not process the back surface solar cell, wherein, Figure 3a is the surface of the antimony selenide film without carbon disulfide back surface treatment, and Figure 3b is the surface of the antimony selenide film after carbon disulfide treatment; the four peaks distributed from left to right in Figure 3a and Figure 3b have their curves respectively Corresponding to Se ⁰ 3d _3/2 , Se ⁰ 3d _5/2 , Se ^2- 3d _3/2 , Se ^2- 3d _5/2 ;

Fig. 4 is the current-voltage curve of the solar cell device prepared in the embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute a conflict with each other.

The method for treating the back surface of the antimony selenide thin film solar cell in the present invention is to use carbon disulfide to treat the back surface of the antimony selenide thin film solar cell; that is, drop the carbon disulfide liquid on the back surface of the antimony selenide thin film solar cell, and let it stand for a while Time T; then place the battery on a glue homogenizer to dry it, then wash it with deionized water and dry it.

The preparation method of the corresponding antimony selenide thin film solar cell may comprise the following steps:

1) Clean the ITO or FTO substrate;

2) Depositing an n-type buffer layer (such as cadmium sulfide, zinc oxide, titanium dioxide, etc.) on the substrate;

3) Prepare antimony selenide thin films by methods such as rapid thermal evaporation;

4) Use carbon disulfide to treat the back surface of the antimony selenide film: drop carbon disulfide liquid on the surface of the antimony selenide film (for example, it can cover the entire surface of the antimony selenide film) at normal temperature (such as 20 ° C ~ 30 ° C), Stand still for 10-30s, then use a glue homogenizer at a speed of 1000-3000 rpm, dry it for 30-50s, and finally clean the surface with deionized water, and use a glue homogenizer at a speed of 1000-3000 revolutions per minute , the time is 30-50s to dry;

Preferably, the carbon disulfide is left standing on the surface of the antimony selenide thin film for 30s.

Preferably, the homogenizer is set at 3000 revolutions per minute, and the time is 30s.

5) Electrodes are plated on the treated antimony selenide thin film to obtain a treated antimony selenide thin film solar cell on the back surface; preferably, the solar cell can be further subjected to a current-voltage test under standard sunlight.

The following are specific examples:

Example 1

Specific steps are as follows:

1) Soak the FTO conductive substrate sequentially with detergent, acetone, isopropanol, ethanol and deionized water for 30 minutes, and then dry it with nitrogen;

2) The FTO conductive substrate is placed on a hot stage, and a layer of zinc oxide film of about 60 nm is deposited by spray pyrolysis;

3) Deposit a layer of antimony selenide film of about 500nm on the prepared zinc oxide film by rapid thermal evaporation;

4) Drop pure carbon disulfide on the prepared antimony selenide film, let it stand for 10s, use a glue spreader to rotate at a speed of 1000 rpm, and dry it for 50s, and finally clean the surface with deionized water, and use a glue spreader to dry it. Dry at 1000 revolutions per minute for 50 seconds;

5) A 60nm gold electrode was deposited by thermal evaporation to obtain an antimony selenide thin-film solar cell, and a current-voltage test was performed on it under standard sunlight. The device performance table and current-voltage curve are shown in Table 1 and Figure 4, respectively.

Example 2:

Specific steps are as follows:

1) Soak the FTO conductive substrate sequentially with detergent, acetone, isopropanol, ethanol and deionized water for 30 minutes, and then dry it with nitrogen;

2) The FTO conductive substrate is placed on a hot stage, and a layer of zinc oxide film of about 60 nm is deposited by spray pyrolysis;

3) Deposit a layer of antimony selenide film of about 500nm on the prepared zinc oxide film by rapid thermal evaporation;

4) Drop pure carbon disulfide on the prepared antimony selenide film, let it stand for 20s, and dry it with a glue spreader at a speed of 2000 rpm for 40s, and finally clean the surface with deionized water, and use a glue spreader to dry it. Dry at 2000 revolutions per minute at a speed of 40 seconds;

5) A 60nm gold electrode was deposited by thermal evaporation to obtain an antimony selenide thin-film solar cell, and a current-voltage test was performed on it under standard sunlight. The device performance table and current-voltage curve are shown in Table 1 and Figure 4, respectively.

Example 3:

Specific steps are as follows:

1) Soak the FTO conductive substrate sequentially with detergent, acetone, isopropanol, ethanol and deionized water for 30 minutes, and then dry it with nitrogen;

2) The FTO conductive substrate is placed on a hot stage, and a layer of zinc oxide film of about 60 nm is deposited by spray pyrolysis;

3) Deposit a layer of antimony selenide film of about 500nm on the prepared zinc oxide film by rapid thermal evaporation;

4) Drop pure carbon disulfide on the prepared antimony selenide film, let it stand for 30s, and dry it with a glue spreader at a speed of 3000 rpm for 30s, and finally clean the surface with deionized water, and use a glue spreader to dry it. Dry at a speed of 3000 revolutions per minute and a drying time of 30s;

5) A 60nm gold electrode was deposited by thermal evaporation to obtain an antimony selenide thin-film solar cell, and a current-voltage test was performed on it under standard sunlight. The device performance table and current-voltage curve are shown in Table 1 and Figure 4, respectively.

Example 4

Specific steps are as follows:

1) Soak the FTO conductive substrate sequentially with detergent, acetone, isopropanol, ethanol and deionized water for 30 minutes, and then dry it with nitrogen;

2) The FTO conductive substrate is placed on a hot stage, and a layer of zinc oxide film of about 60 nm is deposited by spray pyrolysis;

3) Deposit a layer of antimony selenide film of about 500nm on the prepared zinc oxide film by rapid thermal evaporation;

4) Drop the ethanol solution with a volume percentage concentration of 50% carbon disulfide on the prepared antimony selenide film, let it stand for 10 minutes, and dry it with a glue homogenizer at a speed of 3000 rpm for 30 seconds, and finally use it Clean the surface with ionized water, and dry it with a homogenizer at a speed of 3000 rpm for 30s;

5) A 60nm gold electrode was deposited by thermal evaporation to obtain an antimony selenide thin film solar cell.

Example 5

Specific steps are as follows:

1) Soak the FTO conductive substrate sequentially with detergent, acetone, isopropanol, ethanol and deionized water for 30 minutes, and then dry it with nitrogen;

2) The FTO conductive substrate is placed on a hot stage, and a layer of zinc oxide film of about 60 nm is deposited by spray pyrolysis;

3) Deposit a layer of antimony selenide film of about 500nm on the prepared zinc oxide film by rapid thermal evaporation;

4) Drop the ethanol solution with a volume percentage concentration of 50% carbon disulfide on the prepared antimony selenide film, let it stand for 10 seconds, use a glue homogenizer with a speed of 3000 revolutions per minute, and dry it for 30 seconds, and finally use it Clean the surface with ionized water, and dry it with a homogenizer at a speed of 3000 rpm for 30s;

5) A 60nm gold electrode was deposited by thermal evaporation to obtain an antimony selenide thin film solar cell.

Comparative example 1 (that is, antimony selenide thin film solar cell without carbon disulfide back surface treatment)

In this comparative example 1, except that the back surface of the carbon disulfide is not treated, other steps are the same as in Example 1.

The performance table of the solar cell that the embodiment of table 1 makes

Comparative example 2

In this comparative example 2, other steps are the same as in Example 3 except that pure hydrazine solution is used instead of carbon disulfide.

Comparative example 3

This comparative example 3 is except replacing carbon disulfide with pure acetic acid, other steps are identical with embodiment 3.

The performance table of the solar cell that table 2 comparative example 2,3 makes

Voc(V) Jsc(mA/cm ² ) FF(%) Eff(%) Rs. Rsh Comparative example 2 0.37 27.0 48.2 4.8 44 1202 Comparative example 3 0.35 25.7 46.8 4.2 52 1283

It can be seen from the above Table 2 that the fill factor FF of the solar cells prepared in Comparative Example 2 and Comparative Example 3 is similar to that of the solar cells in Comparative Example 1 without carbon disulfide back surface treatment, and the photoelectric conversion efficiency of the solar cells has not been significantly improved.

In addition to the antimony selenide thin film solar cell with the above-mentioned specific structure adopted in the above embodiments, the antimony selenide thin film solar cell targeted by the present invention can also be prepared by other antimony selenide thin film solar cell processes in the prior art, corresponding , the prepared antimony selenide thin film solar cells can also have different layer structures, as long as the back surfaces of these antimony selenide thin film solar cells are treated by the treatment method in the present invention. For example, after the back surface of the antimony selenide thin film layer is processed, other semiconductor layers can be deposited on the back surface first, and finally gold electrodes are deposited to form an antimony selenide thin film solar cell with another structure ( Of course, other materials can also be used for the electrodes).

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, All should be included within the protection scope of the present invention.

Claims (13)

1. a kind of back surface processing method of antimony selenide thin-film solar cells, it is characterised in that this method, which uses, contains two sulphur Change the surface of antimony selenide film layer in the liquid contact processing antimony selenide thin-film solar cells of carbon, and with the selenizing after processing Back surface of the surface of Sb film layer as antimony selenide thin-film solar cells.

2. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 1, it is characterised in that the use The surface of liquid contact processing antimony selenide film layer containing carbon disulfide, is that the liquid containing carbon disulfide is added dropwise On the surface of the antimony selenide film layer, stewing process removes the liquid for containing carbon disulfide again after for a period of time.

3. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 2, it is characterised in that the removal Liquid containing carbon disulfide is dried using sol evenning machine.

4. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 3, it is characterised in that the sol evenning machine It is to be turned using 1000-3000 per minute, the drying time is 30-50s.

5. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 2, it is characterised in that should removing After liquid containing carbon disulfide, the surface of the antimony selenide film layer is also cleaned using deionized water, the deionized water is Dried using sol evenning machine.

6. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 5, it is characterised in that the sol evenning machine It is to be turned using 1000-3000 per minute, the drying time is 30-50s.

7. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 1, it is characterised in that the use The surface of liquid contact processing antimony selenide film layer containing carbon disulfide, carries out at 20 DEG C~30 DEG C.

8. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 1, it is characterised in that described to contain The liquid of carbon disulfide is pure carbon disulfide liquid, and the pure carbon disulfide liquid stands the time for contacting the antimony selenide film layer For 10s~30s.

9. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 1, it is characterised in that described to contain The liquid of carbon disulfide is carbon disulfide solution, and the percent by volume of solute carbon disulfide is 50%- in the carbon disulfide solution 100%, solvent is organic solvent；The time that the carbon disulfide solution left standstill contacts the antimony selenide film layer is 10s-10min.

10. the back surface processing method of antimony selenide thin-film solar cells as claimed in claim 9, it is characterised in that described to have Solvent is at least one of ethanol, ether.

11. a kind of preparation method of antimony selenide thin-film solar cells, it is characterised in that comprise the following steps：

Using transparent conducting glass as substrate, depositing n-type semiconductor buffer layer over the substrate；Then, delay in the n-type semiconductor Rush on layer and prepare antimony selenide film layer；Then, the antimony selenide film layer is handled using the liquid contact containing carbon disulfide Surface；Then, electrode is prepared on the surface of the antimony selenide film layer after processing, so as to form antimony selenide thin film solar electricity Pond.

12. the preparation method of antimony selenide thin-film solar cells as claimed in claim 11, it is characterised in that the N-shaped is partly led Body cushion is cadmium sulfide, zinc oxide or titanium dioxide.

13. the preparation method of antimony selenide thin-film solar cells as claimed in claim 11, it is characterised in that the electrically conducting transparent Glass is ITO or FTO.