Perovskite multilayer SnO2 buffer film, cell and preparation method of perovskite multilayer SnO2 buffer film

Abstract

The invention discloses a perovskite multilayer SnO2 buffer film, a battery and a preparation method of the perovskite multilayer SnO2 buffer film, the perovskite multilayer SnO2 buffer film sequentially comprises a pretreatment film layer, a first SnO2 film layer and a second SnO2 film layer, and the thickness of the first SnO2 film layer is smaller than that of the second SnO2 film layer. The perovskite multilayer SnO2 buffer film provided by the invention comprises at least three film layers, and the deposition rate and thickness of each film layer can be controlled. According to the multilayer SnO2 buffer film prepared by utilizing the linear reciprocating atomic layer deposition equipment, the film uniformity of a large-size substrate is ensured, the film uniformity is improved, the deposition rate is increased to a certain extent, the process time is saved, and the production takt is optimized.

Description

Technical Field

[0001] The present invention relates to a buffer film, a battery and a preparation method thereof, and in particular to a perovskite multilayer SnO 2 Buffer film, battery and preparation method thereof. Background Art

[0002] SnO 2 As an important component of perovskite battery devices, the buffer layer can effectively transmit electrons. 2 As a promising electron transport material, SnO has been well studied in many perovskite solar cells due to its high mobility, wide band gap, deep conduction band and valence band. 2 It is a common technique.

[0003] Spatial isolation atomic layer deposition (SALD) technology is a thin film growth technology developed based on ALD technology, including rotary SALD, roll-to-roll SALD and linear reciprocating SALD. Compared with the traditional time-isolated atomic layer deposition technology, spatial isolation atomic layer deposition technology has the characteristics of large area, large scale, continuous production and even application on flexible substrates. However, the use of linear reciprocating SALD to prepare SnO 2 When forming thin films, the substrate movement speed affects the distribution range of precursor concentration. Too fast a speed causes airflow disturbance, which in turn increases the chemical vapor deposition (CVD) reaction and affects the film quality. Too slow a speed affects the deposition rate, resulting in increased film formation time and affecting the production cycle. Therefore, it is necessary to develop a process that can optimize both film quality and film formation rate. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a perovskite multilayer SnO 2 The buffer film, battery and preparation method thereof are suitable for linear reciprocating space-type atomic layer deposition equipment, solving the problem of preparing SnO 2 Excessive CVD reactions may result in poor film quality and slow deposition rates.

[0005] The technical solution adopted by the present invention to solve the above technical problems is to provide a perovskite multilayer SnO 2 The buffer film includes a pretreatment film layer, a first layer of SnO 2 film and the second layer SnO 2 The first SnO film 2 The film thickness is smaller than the second layer SnO 2 The thickness of the film.

[0006] Furthermore, the first layer of SnO 2 The thickness of the film is 4-6nm, and the first layer of SnO 2 The thickness of the film was 14-16 nm.

[0007] In order to solve the above technical problems, the present invention also provides a trans-structured perovskite battery, comprising FTO glass, wherein a nickel oxide hole transport layer, a perovskite layer, a C 60 Electron transport layer, pretreatment film layer and multilayer SnO 2 buffer film, the multilayer SnO 2 The buffer film is the above-mentioned perovskite multilayer SnO 2 Buffer film.

[0008] Furthermore, the specification of the FTO glass is 2.5×2.5 cm; the thickness of the nickel oxide hole transport layer is 20 nm, and it is prepared on the surface of the FTO glass by magnetron sputtering; the thickness of the perovskite layer is 600 nm, and it is prepared on the surface of the nickel oxide hole transport layer by blade coating; 60 The thickness of the electron transport layer is 10 nm and is prepared on the surface of the perovskite layer by evaporation.

[0009] In order to solve the above technical problems, the present invention also provides a perovskite multilayer SnO 2 The preparation method of the buffer film comprises the following steps: S1: placing the substrate in a vacuum constant temperature chamber; S2: constructing a pretreatment film, introducing a TDMASn precursor and an isolation gas N 2 The substrate is placed in the chamber, the roller drives the substrate to swing, the first swing speed is set, and the swing substrate is exposed to the TDMASn precursor reaction area and the isolation gas N in sequence. 2 After the substrate is adsorbed in the TDMASn reaction area, it swings to the isolation area to clean the excess precursor and reaction byproducts. After reciprocating motion, a pre-treated film layer is obtained; S3: constructing the first film layer: introducing TDMASn precursor and isolation gas N 2 With H 2 O precursor on the pretreated substrate surface, set a second swing speed, and swing the substrate to expose the TDMASn precursor reaction area, the isolation gas N 2 Reaction area and H 2 O precursor area, after the substrate is adsorbed in the TDMASn reaction area, it is swung to the isolation area to clean the excess precursor and reaction byproducts, and then swung to the H 2 O reaction area to react, realizing a complete atomic layer deposition reaction process. After reciprocating motion, the first layer of SnO 2 S4: construct the second membrane: introduce TDMASn precursor and isolation gas N2 With H 2 O precursor with a first layer of SnO 2 The substrate of the film is set to a third swing speed, and the swing substrate is sequentially exposed to the TDMASn precursor reaction area, the isolation gas N 2 Reaction area and H 2 O precursor area, after the substrate is adsorbed in the TDMASn reaction area, it is swung to the isolation area to clean the excess precursor and reaction byproducts, and then swung to the H 2 O reaction area to react, realizing a complete atomic layer deposition reaction process. After reciprocating motion, the second layer of SnO 2 Membrane; S5: pass through isolation N 2 The chamber is then vacuumed and the process is repeated to clean the remaining reaction gases and by-products in the chamber to obtain a multilayer SnO 2 Buffer film.

[0010] Furthermore, the third swing speed is greater than the first swing speed and the second swing speed, so that the thickness of the first film layer in step S3 is less than the thickness of the second film layer in step S4.

[0011] Furthermore, in step S2, the first swing speed is 4000-6000 mm / min, 400-600 sccm of TDMASn and 7000-8000 sccm of N 2 Mix before entering the chamber as the first process gas; introduce 20000-30000sccm of isolation gas N 2 , as the second process gas, swing the carrier with the substrate for 3-10 times to pre-treat the substrate.

[0012] Furthermore, in step S3, the second swing speed is 4000-6000 m / min, 400-600 sccm of TDMASn and 7000-8000 sccm of N 2 Mix before entering the chamber as the first process gas; introduce 20000-30000sccm of isolation gas N 2 As the second process gas, 100-200 sccm of water vapor and 11000-12000 sccm of N 2 Mix before entering the chamber, as the third process gas, swing the carrier with the substrate, swing 15-20 times, and get the first layer of SnO 2 membrane.

[0013] Furthermore, in step S4, the third swing speed is 8000-10000 mm / min, 400-600 sccm of TDMASn and 7000-8000 sccm of N2 Mix before entering the chamber as the first process gas; introduce 20000-30000sccm of isolation gas N 2 , as the second process gas; 100-200 sccm of water vapor and 11000-12000 sccm of N 2 Mix before entering the chamber, as the third process gas, swing the carrier with the substrate, swing 60-70 times, and get the second layer of SnO 2 membrane.

[0014] Furthermore, in step S5, 10000-15000 sccm of isolation gas N is introduced. 2 , the passage time is 10-20s, followed by vacuuming, the vacuuming time is 30-50s, and repeated 5-10 times.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the perovskite multilayer SnO 2 The buffer film includes at least three film layers, and the deposition rate and thickness of each film layer can be controlled. 2 The buffer film, while ensuring the uniformity of the film layer on large-size substrates, not only improves the uniformity of the film layer, but also increases the deposition rate to a certain extent, saving process time and optimizing the production cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention contains multilayer SnO 2 Schematic diagram of the perovskite cell structure with buffer film; Figure 2 The multilayer SnO 2 Schematic diagram of the preparation process of the buffer film; Figure 3 This is a schematic diagram of the structure of the spatial ALD process chamber used in the present invention; Figure 4 The multilayer SnO 2 Schematic diagram of the test point distribution for the buffer film layer uniformity. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0018] The perovskite multilayer SnO 2 The buffer film includes a pretreatment film layer, a first layer of SnO 2 film and the second layer SnO 2 The first SnO film 2 The film thickness is smaller than the second layer SnO 2Preferably, the thickness of the pre-treated film is less than 1 nm, covering only one Sn atomic layer without generating SnO 2 Film layer: First layer SnO 2 The film thickness ranges from 4 to 6 nm. A thickness below 4 nm affects the film quality, and a thickness above 6 nm increases the coating time. The optimal value is 5 nm. The second layer of SnO 2 The film thickness ranges from 14-16nm. If it is below 14nm, the coating time will be increased, and if it is above 16nm, the film quality will be affected. The optimal value is 15nm.

[0019] The inverse structure perovskite battery provided by the present invention comprises FTO glass, on which a nickel oxide hole transport layer, a perovskite layer, a C 60 Electron transport layer, pretreatment film layer and the above multilayer SnO 2 Buffer film, such as Figure 1 shown.

[0020] Please continue to see Figure 2 The perovskite multilayer SnO 2 The method for preparing a buffer film comprises the following steps: S1: placing the substrate in a vacuum constant temperature chamber; S2: construct a pretreatment membrane, introduce tetrakis(dimethylamino)tin (TDMASn) precursor and isolation gas N 2 The substrate is placed in the chamber, the roller drives the substrate to swing, the first swing speed is set, and the swing substrate is exposed to the TDMASn precursor reaction area and the isolation gas N in sequence. 2 After the substrate has completed adsorption in the TDMASn reaction area, it swings to the isolation area to clean off excess precursors and reaction byproducts. After reciprocating motion, a pre-treated film layer is obtained; S3: Construction of the first film: introduction of TDMASn precursor and isolation gas N 2 With H 2 O precursor on the pretreated substrate surface, set a second swing speed, and swing the substrate to expose the TDMASn precursor reaction area, the isolation gas N 2 Reaction area and H 2 O precursor area, after the substrate is adsorbed in the TDMASn reaction area, it is swung to the isolation area to clean the excess precursor and reaction byproducts, and then swung to the H 2 O reaction area to react, realizing a complete atomic layer deposition reaction process. After reciprocating motion, the first layer of SnO 2 membrane; S4: Construction of the second film: introduction of TDMASn precursor and isolation gas N 2 With H 2 O precursor with a first layer of SnO 2The substrate of the film is set to a third swing speed, and the swing substrate is sequentially exposed to the TDMASn precursor reaction area, the isolation gas N 2 Reaction area and H 2 O precursor area, after the substrate is adsorbed in the TDMASn reaction area, it is swung to the isolation area to clean the excess precursor and reaction byproducts, and then swung to the H 2 O reaction area to react, realizing a complete atomic layer deposition reaction process. After reciprocating motion, the second layer of SnO 2 membrane; S5: Pass into isolation N 2 The chamber is then vacuumed and the process is repeated to clean the remaining reaction gases and by-products in the chamber to obtain a multilayer SnO 2 Buffer film.

[0021] The third swing speed in S4 is greater than the first and second swing speeds in S2 and S3, and the first film thickness in S3 is less than the second film thickness in S4. Preferably, the swing speed is between 4000-10000 mm / min. If the swing speed is lower than 4000 mm / min, the deposition rate will be slow and the coating time will be too long; if the swing speed is higher than 10000 mm / min, the CVD reaction will increase and the film quality will deteriorate.

[0022] Figure 3 Schematic diagram of the structure of the spatial ALD process chamber used in the present invention, wherein the chamber cover ① is used to connect the jet panel and the chamber switch cover; the jet panel ② is used to ensure uniform gas spraying during the process; and the first carrier plate ③ is used to place experimental samples.

[0023] The present invention also provides a method for preparing an inverse structure perovskite battery, comprising the following steps: (1) Cleaning FTO glass with a size of 2.5×2.5 cm; (2) A 20 nm nickel oxide hole transport layer was prepared on the FTO glass surface by magnetron sputtering; (3) Preparing a 600 nm perovskite layer on the surface of the nickel oxide hole transport layer by a doctor blade coating method; (4) Prepare 10 nm C on the surface of the perovskite layer by evaporation 60 Electron transport layer; (5) In C 60 The electron transport layer surface is prepared by the method described above. 2 Buffer film; (6) In multilayer SnO 2 A metal copper electrode is prepared on the surface of the buffer film layer to obtain the inverse perovskite battery structure as shown in Figure 4 shown.

[0024] Example 1 This embodiment provides a multilayer SnO 2 The preparation method of the buffer film, the process flow chart of the preparation method is as follows Figure 1 As shown, the preparation method adopts Figure 2 The spatial ALD device shown in the figure, the preparation method comprises the following steps: In S1, the substrate is placed in a vacuum constant temperature chamber, the vacuum degree of the chamber is 10Pa, and the chamber temperature is 220°C; In S2, the first swing speed is 4000-6000 mm / min, and 400-600 sccm of TDMASn and 7000-8000 sccm of N are introduced. 2 Mix before entering the chamber, as the first process gas, introduce 20000-30000sccm of isolation gas N 2 , as the second process gas, swing the carrier with the substrate for 3-10 times to pre-treat the substrate; In S3, the second swing speed is 4000-6000 m / min, and 400-600 sccm of TDMASn and 7000-8000 sccm of N are introduced. 2 Mix before entering the chamber, as the first process gas, introduce 20000-30000sccm of isolation gas N 2 As the second process gas, 100-200 sccm of water vapor and 11000-12000 sccm of N 2 Mix before entering the chamber, as the third process gas, swing the carrier with the substrate, swing 15-20 times, and get the first layer of SnO 2 membrane; In S4, the third swing speed is 8000-10000 mm / min, and 400-600 sccm of TDMASn and 7000-8000 sccm of N are introduced. 2 Mix before entering the chamber, as the first process gas, introduce 20000-30000sccm of isolation gas N 2 As the second process gas, 100-200 sccm of water vapor and 11000-12000 sccm of N 2 Mix before entering the chamber, as the third process gas, swing the carrier with the substrate, swing 60-70 times, and get the second layer of SnO 2 membrane; In S5, 10000-15000 sccm of isolation gas N is introduced. 2 , the introduction time is 10-20s, followed by vacuuming, the vacuuming time is 30-50s, repeated 5-10 times, and the process is completed to obtain the multilayer SnO2 Buffer film.

[0025] Comparative Example 1 This comparative example provides a single-layer SnO 2 A method for preparing a buffer film, wherein the method adopts the film preparation device as described in Example 1, and the method comprises the following steps: In S1, the substrate is placed in a vacuum constant temperature chamber, the vacuum degree of the chamber is 10Pa, and the chamber temperature is 220°C; In S2, the swing speed is 4000-6000 mm / min, and 400-600 sccm of TDMASn and 7000-8000 sccm of N are introduced. 2 Mix before entering the chamber, as the first process gas, introduce 20000-30000sccm of isolation gas N 2 , as the second process gas, swing the carrier with the substrate for 3-10 times to pre-treat the substrate; In S3, the swing speed is 4000-6000 m / min, and 400-600 sccm of TDMASn and 7000-8000 sccm of N are introduced. 2 Mix before entering the chamber, as the first process gas, introduce 20000-30000sccm of isolation gas N 2 As the second process gas, 100-200 sccm of water vapor and 11000-12000 sccm of N 2 Mix before entering the chamber, as the third process gas, swing the carrier with the substrate, swing 70-80 times, and get a single layer of SnO 2 membrane; S4 is not performed; In S5, 10000-15000 sccm of isolation gas N is introduced. 2 , the introduction time is 10-20s, followed by vacuuming, the vacuuming time is 30-50s, repeated 5-10 times, and the process is completed to obtain the multilayer SnO 2 Buffer film.

[0026] The multilayer SnO prepared in Example 1 and Comparative Example 1 2 Buffer film, film thickness uniformity test is carried out using ellipsometer, the test position is 9 10×10cm glass evenly distributed on 1×2m carrier board, the test points are as follows Figure 4 As shown; the second carrier ④ is used to place the test sample; ⑤ is used to place the multilayer SnO 2The buffer film sample point can be glass or semi-finished cells with perovskite layer prepared, which is used to test the uniformity of the film layer. The uniformity calculation formula is as follows: (Max-Min) / (Max+Min)×100% The film thickness (in nm) and uniformity test results at each point are shown in Table 1 below:

[0027] From the above table, we can see that through a single layer of SnO 2 Layer preparation process (Comparative Example 1) has been able to prepare SnO 2 The film layer, however, adopts the multilayer SnO 2 After the buffer film preparation method, under the premise of ensuring excellent uniformity, the multilayer SnO 2 The buffer film increases the deposition rate, reducing the total coating time from 294 seconds to 266 seconds, saving process time and facilitating the optimization of production cycle.

[0028] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the definition of the claims.

Claims

1. A perovskite multilayer SnO2 buffer film, characterized in that: It includes a pretreatment film layer, a first SnO2 film layer and a second SnO2 film layer in sequence, wherein the thickness of the first SnO2 film layer is smaller than the thickness of the second SnO2 film layer.

2. The perovskite multilayer SnO2 buffer film according to claim 1, characterized in that: The thickness of the first SnO2 film is 4-6 nm, and the thickness of the second SnO2 film is 14-16 nm.

3. An inverse structure perovskite battery, comprising FTO glass, characterized in that: The FTO glass is provided with a nickel oxide hole transport layer, a perovskite layer, a C 60 An electron transport layer, a pretreatment film layer and a multi-layer SnO2 buffer film, wherein the multi-layer SnO2 buffer film is the perovskite multi-layer SnO2 buffer film in claim 1.

4. The inverted perovskite battery according to claim 3, characterized in that: The specification of the FTO glass is 2.5×2.5 cm; the thickness of the nickel oxide hole transport layer is 20 nm, and it is prepared on the surface of the FTO glass by magnetron sputtering; the thickness of the perovskite layer is 600 nm, and it is prepared on the surface of the nickel oxide hole transport layer by scraping; the C 60 The thickness of the electron transport layer is 10 nm and is prepared on the surface of the perovskite layer by evaporation.

5. A method for preparing a perovskite multilayer SnO2 buffer film as claimed in claim 1, characterized in that: The steps include: S1: placing the substrate in a vacuum thermostatic chamber; S2: construct a pretreatment film, introduce TDMASn precursor and isolation gas N2 into the chamber, drive the substrate to swing with a roller, set a first swing speed, and expose the swinging substrate to the TDMASn precursor reaction area and the isolation gas N2 area in turn. After the substrate completes adsorption in the TDMASn reaction area, it swings to the isolation area to clean off excess precursors and reaction by-products. After reciprocating motion, a pretreatment film layer is obtained; S3: constructing the first film: introducing TDMASn precursor, isolation gas N2 and H2O precursor to the pretreated substrate surface, setting a second swing speed, and swinging the substrate to expose it to the TDMASn precursor reaction area, the isolation gas N2 reaction area and the H2O precursor area in turn. After the substrate completes adsorption in the TDMASn reaction area, it swings to the isolation area to clean off excess precursors and reaction by-products, and then swings to the H2O reaction area for reaction, realizing a complete atomic layer deposition reaction process. After reciprocating motion, the first SnO2 film is obtained; S4: constructing the second film: introducing TDMASn precursor, isolation gas N2 and H2O precursor to the substrate with the first SnO2 film, setting a third swing speed, and exposing the swing substrate to the TDMASn precursor reaction area, the isolation gas N2 reaction area and the H2O precursor area in turn. After the substrate completes adsorption in the TDMASn reaction area, it swings to the isolation area to clean off excess precursors and reaction by-products, and then swings to the H2O reaction area for reaction, realizing a complete atomic layer deposition reaction process. After reciprocating motion, a second SnO2 film is obtained; S5: Introduce isolated N2 into the chamber, then evacuate the chamber, repeat this process, clean the remaining reaction gas and by-products in the chamber, and obtain a multilayer SnO2 buffer film.

6. The method for preparing a perovskite multilayer SnO2 buffer film according to claim 5, characterized in that: The third swing speed is greater than the first swing speed and the second swing speed, so that the thickness of the first film layer in step S3 is less than the thickness of the second film layer in step S4.

7. The method for preparing a perovskite multilayer SnO2 buffer film according to claim 5, characterized in that: In the step S2, the first swing speed is 4000-6000 mm / min, 400-600 sccm of TDMASn and 7000-8000 sccm of N2 are introduced and mixed before entering the chamber as the first process gas; 20000-30000 sccm of isolation gas N2 is introduced as the second process gas, and the carrier with the substrate is swung for 3-10 times to pre-treat the substrate.

8. The method for preparing a perovskite multilayer SnO2 buffer film according to claim 5, characterized in that: In the step S3, the second swing speed is 4000-6000m / min, 400-600sccm of TDMASn and 7000-8000sccm of N2 are introduced and mixed before entering the cavity as the first process gas; 20000-30000sccm of isolation gas N2 is introduced as the second process gas, 100-200sccm of water vapor and 11000-12000sccm of N2 are introduced and mixed before entering the cavity as the third process gas, and the carrier with the substrate is swung for 15-20 times to obtain the first layer of SnO2 film.

9. The method for preparing a perovskite multilayer SnO2 buffer film according to claim 5, characterized in that: In the step S4, the third swing speed is 8000-10000 mm / min, 400-600 sccm of TDMASn and 7000-8000 sccm of N2 are introduced and mixed before entering the cavity as the first process gas; 20000-30000 sccm of isolation gas N2 is introduced as the second process gas; 100-200 sccm of water vapor and 11000-12000 sccm of N2 are introduced and mixed before entering the cavity as the third process gas, and the carrier with the substrate is swung for 60-70 times to obtain a second layer of SnO2 film.

10. The method for preparing a perovskite multilayer SnO2 buffer film according to claim 5, characterized in that: In the step S5, 10000-15000 sccm of isolation gas N2 is introduced for 10-20 seconds, followed by vacuuming for 30-50 seconds, which is repeated 5-10 times.

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