CN104916709B - A kind of structure is metal oxide multilayer film/silica-based solar cell - Google Patents

Abstract

The invention discloses a structure of an oxide-metal multilayer film/silicon-based solar cell. The structure of the solar cell includes, from top to bottom, a silver electrode, an oxide-metal multilayer film, a passivation layer, and a silicon substrate. and an all-aluminum back electrode, the oxide-metal multilayer film is composed of a first oxide film, a metal film and a second oxide film, and the first oxide film or the second oxide film is MoO ₃ thin film, tin-doped In ₂ O ₃ thin film, fluorine-doped SnO ₂ thin film or aluminum-doped ZnO thin film, the metal thin film is Ag thin film, Au thin film or Al thin film. The battery can avoid the Auger recombination and dead layer phenomena caused by the traditional thermal diffusion or ion implantation method to prepare the emitter. Also disclosed is a method for preparing the oxide-metal multilayer film/silicon-based solar cell with the above-mentioned structure. The method has few manufacturing steps and is suitable for large-scale production, and the entire preparation process does not require high temperature.

Description

A structure of oxide-metal multilayer film/silicon-based solar cell

technical field

The invention belongs to the technical field of solar cells, and in particular relates to an oxide-metal multilayer film structure/silicon-based solar cell and a preparation method thereof.

Background technique

The most common structure of solar cells is the p-n junction structure of inorganic material system, which can be divided into homojunction and heterojunction according to the similarities and differences of materials. Heterojunction (Heterojunction, HJ) refers to a p-n junction composed of two different semiconductor materials. The concept of heterojunction was proposed by Gubanov et al. in 1951. Heterojunction solar cells can avoid the high-temperature diffusion process, and form p-n junctions with silicon substrates by evaporating thin films at low temperatures. At present, silicon-based heterojunction solar cells mainly include a-Si:H/c-Si heterojunction solar cells (Heterojunction with intrinsic Thinlayer, HIT), AZO/Si heterojunction solar cells, IBC-SHJ solar cells, β- FeSi2/Si heterojunction solar cells. Among them, the HIT solar cell was initially deposited on the surface of silicon by Grigorovici in 1968 by thermal evaporation method. Due to the high density of defect states in the amorphous silicon film, the efficiency is relatively low. Later, with the development of PECVD technology, the deposited amorphous silicon contains hydrogen, which can achieve a good passivation of the contact interface layer between silicon and amorphous silicon. The HIT battery achieved an efficiency of 25.6% in 2014. However, HIT solar cells currently have the following problems: 1. The equipment is expensive, and the raw materials are high-risk chemicals. Second, in order to obtain an amorphous silicon/crystalline silicon interface with a low interface state, the requirements for technology and equipment are relatively high. 3. Amorphous silicon has parasitic absorption of light, which reduces the short-circuit current density. Therefore, it is necessary to find new materials and combine them with silicon to form new heterojunction solar cells.

In recent years, oxide thin film materials such as F-doped SnO ₂ (FTO), In-doped Sn ₂ O ₃ (ITO), Al-doped ZnO (AZO), and MoO ₃ have been widely used in the field of solar cells. In order to further improve the optical and electrical properties of the film, and to achieve low-temperature preparation of transparent conductive films, a metal layer is inserted in the middle of the transparent conductive film, mainly as an oxide/metal/oxide multilayer transparent conductive oxide electrode, such as MoO ₃ /Ag/MoO ₃ , ITO/Ag/ITO, AZO/Ag/AZO, etc. Because they not only have low resistivity, but also the thin film of oxide/metal/oxide composite structure can effectively prevent the reflection of the metal layer, because the plasmonic coupling between the metal layer and the oxide layer makes it visible in the visible light range of increased transmittance. In this sandwich structure with a metal layer embedded in the middle of the oxide layer, the growth method of the metal layer changes from a discontinuous island structure to a continuous film as the thickness increases, which results in a lower sheet resistance.

However, at present, the transparent conductive film with a metal layer embedded in the middle of the oxide layer is only used in organic dye-sensitized solar cells as a low-temperature preparation of transparent conductive films. The oxide-metal multilayer film has not been used in silicon wafers or silicon thin films to make solar cells.

Contents of the invention

The first technical problem to be solved by the present invention is to provide a structure that is an oxide-metal multilayer film/silicon-based solar cell, which uses an oxide-metal multilayer film in a silicon wafer or a silicon thin film as a battery The oxide-metal multilayer film/silicon-based solar cell formed by the emitter can avoid the Auger recombination and dead layer phenomenon caused by the traditional thermal diffusion or ion implantation method to prepare the emitter.

The second technical problem to be solved by the present invention is to provide a preparation method for the oxide-metal multilayer film/silicon-based solar cell with the above-mentioned structure. This method has fewer manufacturing steps and is suitable for large-scale production. The entire preparation process does not require high temperature.

The first technical problem of the present invention is achieved through the following technical solutions: a structure is an oxide-metal multilayer film/silicon-based solar cell, and the structure of the solar cell includes from top to bottom: silver electrode, oxide Object-metal multilayer film, passivation layer, silicon substrate and all-aluminum back electrode, the oxide-metal multilayer film is composed of a first oxide film, a metal film and a second oxide film, and the The first oxide film or the second oxide film is MoO3 film, tin _- doped _In2O3 film, fluorine- _{doped SnO2} film or aluminum-doped ZnO film, and the metal film is Ag film, Au film or Al film .

The present invention forms an oxide-metal multilayer film/silicon-based solar cell by combining an oxide-metal multilayer film with a silicon wafer or a silicon film, and the oxide includes aluminum-doped zinc oxide (AZO), MoO ₃ , indium tin oxide ( ITO), fluorine-doped _SnO2 film, etc., metals include Ag, Au or Al, etc., silicon includes single crystal silicon, polycrystalline silicon or silicon film, etc. The light-absorbing layer of the battery is mainly silicon, and the oxide-metal multilayer film plays the role of emitter, anti-reflection, and conductivity, and the entire preparation process is in a low-temperature state, and the equipment is simple, low in cost, and environmentally friendly.

The thickness of the first oxide film is preferably 10-20 nm, the thickness of the metal film is preferably 2-15 nm, and the thickness of the second oxide film is preferably 30-50 nm.

The silicon substrate can be a single crystal silicon wafer, a polycrystalline silicon wafer or a silicon thin film. Single crystal silicon wafer or polycrystalline silicon wafer is P type or N type single crystal silicon wafer or polycrystalline silicon wafer.

The second technical problem of the present invention is achieved by the following technical scheme: the above-mentioned preparation method of oxide-metal multilayer film structure/silicon-based solar cell comprises the following steps:

(1) Select a crystalline silicon wafer, after cleaning, deposit a passivation layer on the front surface of the crystalline silicon wafer;

(2) depositing a first oxide film on the passivation layer prepared in step (1);

(3) vapor-depositing a metal film on the first oxide film prepared in step (2);

(4) depositing a second oxide film on the metal film prepared in step (3);

(5) A silver electrode is set on the second oxide film deposited in step (4) as the front surface electrode, and an all-aluminum back electrode is set on the back surface of the crystalline silicon.

In the above preparation method with oxide-metal multilayer film structure/silicon-based solar cell:

Cleaning in step (1) is preferably done by RCA process.

The passivation layer described in step (1) is SiO ₂ , TiO ₂ , Al ₂ O ₃ or Si ₃ N ₄ , with a thickness of 1-15 nm, and is prepared by thermal oxidation, PECVD, atomic layer deposition or magnetron sputtering have to.

The first oxide thin film in step (2) and the second oxide thin film in step (4) are prepared by resistive thermal evaporation, electron beam evaporation or magnetron sputtering.

In step (3), the metal thin film is obtained by vapor deposition by resistance thermal evaporation.

In step (4), silver grid lines are prepared as silver electrodes by screen printing method or masked screen resistive thermal evaporation method, the width of the silver grid lines is 0.5-1mm, and the height is 200-300nm.

In step (4), the all-aluminum back electrode is prepared by vapor deposition by resistive thermal evaporation method.

Compared with prior art, the present invention has following advantage:

(1) The battery structure in the present invention is simple, and manufacturing process is few, is suitable for large-scale production;

(2) Using the oxide-metal multilayer film as the emitter of the battery can effectively reduce the Auger recombination and dead layer caused by high doping, reduce recombination, enhance the short-wave response of the solar cell, and increase the short-circuit current of the battery;

(3) During the whole preparation process of the battery of the present invention, there is no high-temperature process, and high-efficiency batteries can be prepared at low temperatures;

(4) The present invention passivates the contact interface between the oxide-metal multilayer film and the silicon wafer or silicon film through the passivation layer, which can reduce the defect state;

(5) The oxide-metal multilayer film/silicon-based solar cell prepared by the present invention is a new structure oxide-metal-oxide multilayer silicon-based solar cell;

(6) Compared with heterojunction solar cells such as HIT and microcrystalline silicon/crystalline silicon, the oxide-metal-oxide multilayer film is used as the emitter of the battery in the present invention, which has simple preparation process and good device performance. The advantages of simple equipment, low cost, energy saving and environmental protection;

(7) The oxide-metal multilayer film/silicon-based solar cell in the present invention has high photoelectric conversion efficiency and has certain application prospects.

Description of drawings

Fig. 1 is the structural diagram of the first oxide-metal-second oxide oxide-metal multilayer film silicon-based solar cell in the embodiment 1-7 of the present invention, wherein 1 is silver electrode, 2 is oxide-metal Multi-layer film, 3 is the passivation layer, 4 is the silicon substrate, 5 is the all-aluminum back electrode;

Fig. 2 is a schematic structural view of the oxide-metal multilayer film in Fig. 1, wherein 21 is a first oxide film, 22 is a metal film, and 23 is a second oxide film;

Fig. 3 is the current density-voltage (JV) figure of MoO ₃ /Ag/MoO ₃ multilayer film silicon-based solar cells prepared in embodiment 1;

Fig. 4 is the optical characteristic diagram of the MoO ₃ /Ag/MoO ₃ oxide-metal multilayer film solar cell prepared in Example 1, the highest transmittance in the visible light part reaches 85%, and the wavelength is 300～1200nm range The average transmittance of the inner oxide-metal multilayer film is 55%, and the average reflectance is 30.8%.

detailed description

The content of the present invention will be further clarified below in conjunction with the drawings and specific embodiments, but these embodiments do not limit the protection scope of the present invention.

Example 1

As shown in Figure 1, the structure provided by this embodiment is an oxide-metal multilayer film/silicon-based solar cell, and the structure of the solar cell includes from top to bottom: a silver electrode 1, an oxide-metal multilayer film 2. The passivation layer 3, the silicon substrate 4 and the all-aluminum back electrode 5, the oxide-metal multilayer film 2 is composed of a first oxide film 21, a metal film 22 and a second oxide film 23, wherein the first The oxide film 21 and the second oxide film 23 are MoO ₃ films, the metal film 22 is an Ag film, and the passivation layer 3 is a SiO ₂ passivation layer.

Wherein the thickness of the first oxide film is 10-20 nm, the thickness of the metal film is 2-15 nm, and the thickness of the second oxide film is 30-50 nm.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, then use the dry oxygen thermal oxidation process to form a _SiO2 passivation layer on the surface of the silicon wafer, set the thermal oxidation temperature to 850°C, and the oxidation time to 1 ～10min, 2～15nm silicon dioxide is formed on the surface of the silicon wafer;

The RCA cleaning process mainly includes SPM (H ₂ SO ₄ :H ₂ O ₂ =3:1) to remove organic matter, DHF (HF:H ₂ O =1:30) to remove oxide layer, and APM (NH ₄ OH:H ₂ O ₂ :H ₂ O=1:1:5) removes particles, and HPM (HCl:H ₂ O ₂ :H ₂ O=1:1:6) removes metal impurities.

(2) Then prepare a MoO ₃ thin film on the surface of the passivation layer by a resistive thermal evaporation coating machine, the vacuum degree is about 5×10 ^-4 Pa, and the thickness of the film is 10-20nm;

(3) Use a resistive thermal evaporation coating machine to vapor-deposit gold, silver, or aluminum films, the vacuum degree is about 8×10 ^-4 Pa, and the film thickness is 2-15nm;

(4) Then use the resistance thermal evaporation coating machine again to prepare the MoO ₃ thin film, the vacuum degree is about 5×10 ^-4 Pa, and the thickness of the film is 30-50nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-SiO ₂ -MoO ₃ /Ag/MoO ₃ -Ag battery is obtained, and the efficiency of the battery is shown in Figure 3. The MoO ₃ /Ag/MoO ₃ prepared in this example The short-circuit current density of the multilayer silicon-based solar cell is 27.012mA/cm ² , the open-circuit voltage is 0.464V, the fill factor is 63.17%, and the efficiency is 7.92%. The MoO ₃ /Ag/MoO ₃ oxide prepared in this example- The optical characteristics of the metal multilayer film solar cell are shown in Figure 4. It can be seen from Figure 4 that the highest transmittance in the visible light part reaches 85%, and the oxide-metal multilayer solar cell has a wavelength of 300-1200nm The average transmittance of the layer film is 55%, and the average reflectance is 30.8%.

Example 2

The structure provided in this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the passivation layer 3 is an Al ₂ O ₃ passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, then use atomic layer deposition (ALD) technology to deposit a layer of Al ₂ O ₃ passivation layer on the surface of the silicon wafer, set the deposition temperature to 200°C, The pulse time of Al(TMA), N ₂ , and H ₂ O are: 0.1s, 10s, and 0.1s, respectively, and the flow rates are: 150sccm, 150sccm, and 200sccm, respectively, and 10-30 cycles are performed to deposit 1-3nm on the surface of the silicon wafer. alumina;

(2) Then prepare a MoO ₃ thin film on the surface of the passivation layer by a resistive thermal evaporation coating machine, the vacuum degree is 5×10 ^{- 4} Pa, and the thickness of the film is 10-20nm;

(3) Use a resistive thermal evaporation coating machine to vapor-deposit silver film, the vacuum degree is 8×10 ^-4 Pa, and the film thickness is 2-15nm;

(4) Then use the resistance thermal evaporation coating machine again to prepare the MoO ₃ thin film, the degree of vacuum is 5×10 ^-4 Pa, and the thickness of the film is 30-50 nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-Al ₂ O ₃ -MoO ₃ /Ag/MoO ₃ -Ag battery is produced.

Example 3

The structure provided in this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the passivation layer 3 is a _TiO2 passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, and then use atomic layer deposition (ALD) technology to deposit a layer of _TiO2 passivation layer on the surface of the silicon wafer, set the deposition temperature to 200-300 °C, The pulse times of TiCl ₄ , N ₂ , and H ₂ O are: 1s, 3s, and 1s, respectively, and the flow rates are: 150sccm, 150sccm, and 200sccm, respectively, and 10-30 cycles are performed to deposit 1-3nm titanium dioxide on the surface of the silicon wafer;

(2) Then prepare a MoO ₃ thin film on the surface of the passivation layer by a resistive thermal evaporation coating machine, the vacuum degree is 5×10 ^{- 4} Pa, and the thickness of the film is 10-20nm;

(3) Use a resistive thermal evaporation coating machine to vapor-deposit silver film, the vacuum degree is 8×10 ^-4 Pa, and the film thickness is 2-15nm;

(4) Then use the resistance thermal evaporation coating machine again to prepare the MoO ₃ thin film, the degree of vacuum is 5×10 ^-4 Pa, and the thickness of the film is 30-50 nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-TiO ₂ -MoO ₃ /Ag/MoO ₃ -Ag battery is produced.

Example 4

The structure provided in this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the passivation layer 3 is a Si ₃ N ₄ passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, then use plasma enhanced chemical vapor deposition (PECVD) technology to deposit a layer of Si ₃ N ₄ passivation layer on the surface of the silicon wafer, set the deposition temperature 200-300°C, pressure 5×10 ^-3 Pa, NH ₃ : SiH ₄ 60:45 sccm, 2-6nm silicon nitride formed after 1-3 minutes;

(2) Then prepare a MoO ₃ thin film on the surface of the passivation layer by a resistive thermal evaporation coating machine, the vacuum degree is 5×10 ^{- 4} Pa, and the thickness of the film is 10-20nm;

(3) Use a resistive thermal evaporation coating machine to vapor-deposit gold, silver, or aluminum films with a vacuum degree of 8×10 ^-4 Pa and a film thickness of 2 to 15 nm;

(4) Then use the resistance thermal evaporation coating machine again to prepare the MoO ₃ thin film, the degree of vacuum is 5×10 ^-4 Pa, and the thickness of the film is 30-50 nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-Si ₃ N ₄ -MoO ₃ /Ag/MoO ₃ -Ag battery is produced.

Example 5

The structure provided by this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the first oxide film 21 is an ITO film, and the second oxide film ₂₃ is a MoO3 film. Layer 3 is an aluminum oxide passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, and then use atomic layer deposition (ALD) technology to deposit a passivation layer on the surface of the silicon wafer, set the deposition temperature to 200 ° C, Al(TMA) The pulse time of , N ₂ , and H ₂ O is: 0.1s, 10s, and 0.1s, respectively, and the flow rates are: 150sccm, 150sccm, and 200sccm, respectively, and 10-30 cycles are performed to deposit 1-3nm aluminum oxide on the surface of the silicon wafer;

(2) Then prepare an ITO thin film on the surface of the passivation layer by an electron beam evaporation coating machine, the vacuum degree is 5 × 10 ^-4 Pa, and the thickness of the film is 10-20nm;

(3) Use a resistive thermal evaporation coating machine to vapor-deposit gold and silver films, the vacuum degree is 8×10 ^-4 Pa, and the film thickness is 2-15nm;

(4) Then use electron beam evaporation again to prepare a coating machine to prepare a MoO ₃ thin film, the vacuum degree is 5×10 ^-4 Pa, and the thickness of the film is 30-50 nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-Al ₂ O ₃ -ITO/Ag/ITO-Ag battery is produced.

Example 6

The structure provided in this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the first oxide film 21 is an AZO film, the second oxide film 23 is an AZO film, and the passivation Layer 3 is an aluminum oxide passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with RCA process, and then use atomic layer deposition (ALD) technology to deposit a passivation layer on the surface of the silicon wafer, set the deposition temperature to 200 ° C, Al(TMA) The pulse time of , N ₂ , and H ₂ O is: 0.1s, 10s, and 0.1s, respectively, and the flow rates are: 150sccm, 150sccm, and 200sccm, respectively, and 10-30 cycles are performed to deposit 1-3nm aluminum oxide on the surface of the silicon wafer;

(2) Then prepare an AZO film on the surface of the passivation layer by radio frequency magnetron sputtering, the degree of vacuum is 5 × 10 ^-4 Pa, and the thickness of the film is 10-20nm;

(3) Electron beam evaporation is used to prepare an aluminum thin film, the vacuum degree is 8×10 ^-4 Pa, and the film thickness is 2-15 nm;

(4) Then use electron beam evaporation to prepare AZO film again, the vacuum degree is 5×10 ^-4 Pa, and the thickness of the film is 30-50nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-Al ₂ O ₃ -AZO/Ag/AZO-Ag battery is produced.

Example 7

The structure provided in this embodiment is an oxide-metal multilayer film/silicon-based solar cell. The difference from Embodiment 1 is that the first oxide film 21 is an AZO film, the second oxide film 23 is an AZO film, and the passivation Layer 3 is a silicon dioxide passivation layer.

The above structure is an oxide-metal multilayer film/silicon-based solar cell, which is prepared by the following method:

(1) Clean the n-type or p-type single crystal silicon wafer with the RCA process, then use the dry oxygen thermal oxidation process to deposit a passivation layer on the surface of the silicon wafer, set the thermal oxidation temperature to 850°C, and the oxidation time to 1 ～10min, 2～15nm silicon dioxide is formed on the surface of the silicon wafer;

(2) Then prepare a ZnO thin film on the surface of the passivation layer by radio frequency magnetron sputtering, the degree of vacuum is 5 × 10 ^-4 Pa, and the thickness of the film is 10-20nm;

(3) Then use radio frequency magnetron sputtering gold thin film, the vacuum degree is 8×10 ^-4 Pa, and the film thickness is 2-15nm;

(4) Then use radio frequency magnetron sputtering to prepare ZnO film again, the degree of vacuum is 5×10 ^-4 Pa, and the thickness of film is 30～50nm;

(5) Using mask screen resistive thermal evaporation coating machine to vapor-deposit silver grid lines as the front surface electrodes, the width of the grid lines is 0.5-1mm, and the height is 200-300nm; finally, the all-aluminum back electrode is evaporated by resistive thermal evaporation, Finally, an Al-Si(n or p)-Al ₂ O ₃ -ZnO/Ag/ZnO-Ag battery is produced.

Apparently, the above content is only to illustrate the characteristics of the present invention, but not to limit the present invention. Changes made by persons of ordinary skill in the relevant technical field in the corresponding technical field according to the present invention shall belong to the protection scope of the present invention.

Claims (9)

1. a kind of structure is oxide-metal multilayer film/silica-based solar cell, it is characterized in that the structure of the solar cell is from up to Under include successively：Silver electrode, oxide-metal multilayer film, passivation layer, silicon substrate and full aluminum back electrode, described oxide-gold Category multilayer film is composited by the first sull, metallic film and the second sull, and the first described oxide is thin Film or the second sull are MoO₃Film, mix tin In₂O₃Film, fluorine doped SnO₂Film mixes aluminium ZnO film, described gold Category film is Ag films, Au films or Al films；The thickness of the first described sull is 10~20nm, described metal The thickness of film is 2~15nm, and the thickness of the second described sull is 30~50nm；Described passivation layer is SiO₂、 TiO₂、Al₂O₃Or Si₃N₄, its thickness is 1~15nm.

2. structure according to claim 1 is oxide-metal multilayer film/silica-based solar cell, it is characterized in that：Described Silicon substrate is monocrystalline silicon or polysilicon.

3. the structure described in claim 1 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is characterized in that Comprise the following steps：

(1) crystal silicon chip is chosen, after cleaning, in the preceding surface deposit passivation layer of crystal silicon chip；

(2) the depositing first oxide film on passivation layer prepared by step (1)；

(3) metal film on the first sull prepared by step (2)；

(4) the depositing second oxide film on metallic film prepared by step (3)；

(5) silver electrode is set on the second sull that step (4) is deposited as front surface electrode, at the back side of crystalline silicon Full aluminum back electrode is set.

4. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：Cleaning is using the cleaning of RCA techniques in step (1).

5. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：Passivation layer described in step (1) is SiO₂、TiO₂、Al₂O₃Or Si₃N₄, its thickness be 1~15nm, using thermal oxide, PECVD, ald or magnetron sputtering method are made.

6. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：The second sull uses resistance-type thermal evaporation, electron beam in the first sull and step (4) in step (2) Evaporation or magnetron sputtering method are made.

7. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：Metallic film is made using resistance-type thermal evaporation evaporation in step (3).

8. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：Silver grating line is prepared as silver electrode using silk screen print method or mask half tone resistance-type thermal evaporation in step (5), silver-colored grid 0.5~1mm of width of line, is highly 200~300nm.

9. structure according to claim 3 is the preparation method of oxide-metal multilayer film/silica-based solar cell, it is special Levying is：Full aluminum back electrode is made using resistance-type thermal evaporation evaporation in step (5).