CN105097962A - Solar cell anti-reflection film and preparation method thereof - Google Patents

Abstract

The invention relates to a solar cell anti-reflection film and a preparation method thereof. The solar cell anti-reflection film comprises a silicon nitride oxide thin film layer, a nano-titanium dioxide layer, a silicon nitride layer, a silicon dioxide layer and an amorphous silicon layer deposited on the surface of a silicon wafer in sequence. The preparation method comprises feeding a silicon wafer, a silicon hydride and nitrogen gas into a plasma-enhanced chemical vapor deposition device to deposit a silicon oxynitride film layer on the surface of the silicon wafer, and then feeding a nano-titanium dioxide and an inert gas to deposit a nano-titanium dioxide layer, and then passing The step of depositing a silicon nitride layer by feeding silane and ammonia gas, then depositing a silicon dioxide layer by feeding silicon dioxide, and finally depositing an amorphous silicon layer by feeding silane and hydrogen gas. The present invention adopts a multi-layer film, which can have the effect of anti-reflection on multiple specific wavelengths at the same time, and the thickness and refractive index of the film of the present invention are controllable, so that it can simultaneously play a better anti-reflection effect on multiple light energies of different wavelengths. Effect: The preparation method has mild conditions and is easy to manipulate.

Description

A kind of solar cell anti-reflection film and preparation method thereof

technical field

The invention relates to the field of new energy technologies, in particular to the field of anti-reflection films for solar cells, in particular to an anti-reflection film for solar cells and a preparation method thereof.

Background technique

With the rapid development of human society, environmental degradation and energy shortage have become the most prominent problems in the world. At present, more than 70% of the world's total energy consumption comes from non-renewable energy sources such as oil, natural gas, and coal. Long-term and large-scale utilization of these non-renewable energy sources will cause many harms. Solar energy is an ideal clean and renewable new energy source, which can alleviate energy shortage and environmental pollution. A solar cell is a device that directly converts solar radiation energy into electrical energy. At present, crystalline silicon solar cells account for about 80% of the world's solar cell production. Crystalline silicon solar cell power generation is a power generation method that uses solar cells to absorb sunlight with a wavelength of 0.4 μm to 1.1 μm, and directly converts light energy into electrical energy output. How to improve the conversion efficiency of crystalline silicon solar cells, one of the most important measures is to coat the silicon wafer with an anti-reflection film. Due to the reflection of light on the surface of the silicon wafer, the light loss is as high as 30%. If the silicon surface is coated with a suitable Thin films, using the principle of thin film interference, can greatly reduce the reflection of light, thereby improving the short-circuit photocurrent density and photoelectric conversion efficiency of solar cells. It can be seen that it is very important to coat a layer of anti-reflection film on the surface of the silicon wafer.

CN104241402A discloses an anti-reflection film for a solar cell and a preparation method thereof; wherein the anti-reflection film is composed of an amorphous silicon layer, a first silicon nitride film and a second silicon nitride film that are stacked in sequence, The anti-reflection film of this invention has the effect of passivation and anti-reflection at the same time, but the controllability of the equipment is low, the product identity is not enough, and it is not easy to mass-produce. CN101989623A discloses an anti-reflection film for a solar cell and a preparation method thereof, wherein the anti-reflection film includes a silicon nitride film deposited on the surface of a silicon wafer, the average refractive index is 2.1-2.3, and the average reflectance is 1-10%. ; The preparation method is through the steps of coating the silicon wafer for the first time, cooling and coating for the second time; the anti-reflection film of the invention has uniform thickness and good compactness, and the thickness is controllable, but the adhesion is poor, which affects its reflection efficiency , and the deposition conditions are more stringent.

Contents of the invention

One of the objects of the present invention is to provide a solar cell anti-reflection film with good reflectivity and refractive index and good film uniformity and its preparation method;

The second object of the present invention is to provide a method for preparing a solar anti-reflection film with mild conditions, easy popularization and application, and broad market prospects. In order to achieve the above object, the present invention adopts the following technical solutions:

In a first aspect, the present invention provides an antireflection film for a solar cell, comprising a silicon nitride oxide thin film layer, a nano-titanium dioxide layer, a silicon nitride layer, a silicon dioxide layer and an amorphous silicon layer sequentially stacked and deposited on the surface of a silicon wafer.

Preferably, the thickness of the silicon oxynitride film layer is 25-30nm, such as 25nm, 25.5nm, 26nm, 26.5nm, 27nm, 27.5nm, 28nm, 28.5nm, 29nm, 29.5nm or 30nm; the refractive index 2.15～2.36, such as 2.15, 2.16, 2.17, 2.18, 2.19, 2.2, 2.21, 2.22, 2.23, 2.24, 2.25, 2.26, 2.27, 2.28, 2.29, 2.3, 2.31, 2.32, 2.33, 2.34, 2.35 or 2.36 .

Preferably, the thickness of the nano-titanium dioxide layer is 28-32nm, such as 28nm, 28.5nm, 29nm, 29.5nm, 30nm, 30.5nm, 31nm, 31.5nm or 32nm; the refractive index is 2.1-2.2, such as 2.1, 2.11, 2.12, 2.13, 2.14, 2.15, 2.16, 2.17, 2.18, 2.19, or 2.2.

Preferably, the thickness of the silicon nitride layer is 35-42nm, for example, 35nm, 35.5nm, 36nm, 36.5nm, 37nm, 37.5nm, 38nm, 38.5nm, 39nm, 39.5nm, 40nm, 40.5nm, 41nm , 41.5nm or 42nm; the refractive index is 2.2 to 2.4, such as 2.2, 2.21, 2.22, 2.23, 2.24, 2.25, 2.26, 2.27, 2.28, 2.29, 2.3, 2.31, 2.32, 2.33, 2.34, 2.35, 2.36, 2.37, 2.38, 2.39 or 2.4.

The thickness of the silicon dioxide layer is 45-55nm, such as 45nm, 46nm, 47nm, 48nm, 49nm, 50nm, 51nm, 52nm, 53nm, 54nm or 55nm; the refractive index is 1.4-1.55, such as 1.4, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, 1.5, 1.51, 1.52, 1.53, 1.54, or 1.55.

Preferably, the particle size of silicon oxynitride in the silicon oxynitride thin film layer is 12-15.5 nm, for example, 12 nm, 12.2 nm, 12.4 nm, 12.6 nm, 12.8 nm, 13 nm, 13.2 nm, 13.4 nm, 13.6 nm, 13.8nm, 14nm, 14.2nm, 14.4nm, 14.6nm, 14.8nm, 15nm, 15.2nm, 15.4nm, or 15.5nm.

Preferably, the particle size of the nano-titanium dioxide in the nano-titanium dioxide layer is 8-12nm, such as 8nm, 8.2nm, 8.4nm, 8.6nm, 8.8nm, 9nm, 9.2nm, 9.4nm, 9.6nm, 9.8nm, 10nm , 10.2nm, 10.4nm, 10.6nm, 10.8nm, 11nm, 11.2nm, 11.4nm, 11.6nm, 11.8nm or 12nm.

Preferably, the particle size of the silicon nitride in the silicon nitride layer is 10-15 nm, such as 10 nm, 10.5 nm, 11 nm, 11.5 nm, 12 nm, 12.5 nm, 13 nm, 13.5 nm, 14 nm, 14.5 nm or 15 nm.

Preferably, the silicon dioxide in the silicon dioxide layer has a particle size of 20-25nm, for example, 20nm, 20.5nm, 21nm, 21.5nm, 22nm, 22.5nm, 23nm, 23.5nm, 24nm, 24.5nm or 25nm.

Preferably, the film thicknesses of the silicon oxynitride thin film layer, the nano-titanium dioxide layer, the silicon nitride layer, the silicon dioxide layer and the amorphous silicon layer increase sequentially.

As is well known to those skilled in the art, the anti-reflection film uses the optical path difference generated by the reflection of light on the upper and lower surfaces of the anti-reflection film, so that the two beams of reflected light interfere and cancel each other, thereby weakening the reflection and increasing the incidence, so that the incident light conforms to a certain light beam. process conditions, so as to achieve the effect of anti-reflection, so the present invention adopts multilayer film, can play the effect of anti-reflection to a plurality of specific wavelengths at the same time, and the film thickness and refractive index of the present invention are controllable, make to a plurality of different wavelengths At the same time, it can play a better anti-reflection effect.

In a second aspect, the present invention provides a method for preparing an antireflection film for a solar cell as described in the first aspect, comprising the steps of:

(1) Pass silicon chip, silicon hydride and nitrogen in the plasma-enhanced chemical vapor deposition equipment, make the silicon nitride oxide film deposited on the surface of the silicon chip;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer;

(3) continue to feed silane and ammonia in the plasma-enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer;

(4) Continue to feed silicon dioxide in the plasma enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer;

(5) Continue to feed silane and hydrogen into the plasma enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer.

Preferably, the flow ratio of silicon wafer, silicon hydride and nitrogen in step (1) is 1:(1~4):(1~3), for example, it can be 1:1:1, 1:2:1, 1:3:1, 1:4:1, 1:1:2, 1:1:3, 1:2:2, 1:2:3, 1:3:2, 1:3:3, 1: 4:2 or 1:4:3.

Preferably, the frequency of the plasma-enhanced chemical vapor deposition equipment is 12-16MHz, such as 12MHz, 12.5MHz, 13MHz, 13.5MHz, 14MHz, 14.5MHz, 15MHz, 15.5MHz or 16MHz; the gas pressure is 20-80Pa , such as 20Pa, 25Pa, 30Pa, 35Pa, 40Pa, 45Pa, 50Pa, 55Pa, 60Pa, 65Pa, 70Pa, 75Pa or 80Pa; the temperature is 100-300°C, such as 100°C, 110°C, 120°C, 130°C ℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃ or 300°C; RF power is 3500~6000W, such as 3500W, 3600W, 3700W, 3800W, 3900W, 4000W, 4100W, 4200W, 4300W, 4400W, 4500W, 4600W, 4700W, 4800W, 4900W, 5000W, 50000W, 5300W, 5300W , 5400W, 5500W, 5600W, 5700W, 5800W, 5900W or 6000W; the deposition power is 38-70W, for example, it can be 38W, 39W, 40W, 41W, 42W, 43W, 44W, 45W, 46W, 47W, 48W, 49W, 50W , 51W, 52W, 53W, 54W, 55W, 56W, 57W, 58W, 59W, 60W, 61W, 62W, 63W, 64W, 65W, 66W, 67W, 68W, 69W, or 70W.

Preferably, the inert gas in step (2) is any one or a mixture of at least two of neon, argon or helium.

Preferably, the flow ratio of the nano-titanium dioxide and the inert gas is 1:(10-25), such as 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1 :16, 1:17, 1:18, 1:19, 1:20, 1:21, 1:22, 1:23, 1:24, or 1:25.

Preferably, the frequency of the plasma-enhanced chemical vapor deposition equipment is 10-13MHz, such as 10MHz, 10.2MHz, 10.4MHz, 10.6MHz, 10.8MHz, 11MHz, 11.2MHz, 11.4MHz, 11.6MHz, 11.8MHz, 12MHz, 12.2MHz, 12.4MHz, 12.6MHz, 12.8MHz or 13MHz; the gas pressure is 20-100Pa, such as 20Pa, 25Pa, 30Pa, 35Pa, 40Pa, 45Pa, 50Pa, 55Pa, 60Pa, 65Pa, 70Pa, 75Pa, 80Pa, 85Pa, 90Pa, 95Pa or 100Pa; the temperature is 150-350°C, such as 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C or 350°C; RF power is 3500-6000W, for example, it can be 3500W, 3600W, 3700W, 3800W , 3900W, 4000W, 4100W, 4200W, 4300W, 4400W, 4500W, 4600W, 4700W, 4800W, 4900W, 5000W, 5100W, 5200W, 5300W, 5400W, 5500W, 5600W, 5700W, 5800W, 59000W; 80W, such as 50W, 51W, 52W, 53W, 54W, 55W, 56W, 57W, 58W, 59W, 60W, 61W, 62W, 63W, 64W, 65W, 66W, 67W, 68W, 69W, 70W, 71W, 72W , 73W, 74W, 75W, 76W, 77W, 78W, 79W or 80W.

Preferably, the flow ratio of silane and ammonia in step (3) is 1: (3-6), for example, it can be 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1: 5.5 or 1:6.

Preferably, the frequency of the plasma-enhanced chemical vapor deposition equipment is 12-16MHz, such as 12MHz, 12.5MHz, 13MHz, 13.5MHz, 14MHz, 14.5MHz, 15MHz, 15.5MHz or 16MHz; the gas pressure is 100-300Pa , such as 100Pa, 110Pa, 120Pa, 130Pa, 140Pa, 150Pa, 160Pa, 170Pa, 180Pa, 190Pa, 200Pa, 210Pa, 220Pa, 230Pa, 240Pa, 250Pa, 260Pa, 270Pa, 280Pa, 290Pa or 300Pa; 300°C, such as 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C . , 4600W, 4700W, 4800W, 4900W, 5000W, 5100W, 5200W, 5300W, 5400W, 5500W, 5600W, 5700W, 5800W, 5900W or 6000W; the deposition power is 38-70W, such as 38W, 39W, 40W, 41W, 42W ,43W,44W,45W,46W,47W,48W,49W,50W,51W,52W,53W,54W,55W,56W,57W,58W,59W,60W,61W,62W,63W,64W,65W,66W,67W , 68W, 69W or 70W.

Preferably, in step (4), the frequency of the plasma-enhanced chemical vapor deposition equipment is 10-15MHz, such as 10MHz, 10.5MHz, 11MHz, 11.5MHz, 12MHz, 12.5MHz, 13MHz, 13.5MHz, 14MHz , 14.5MHz or 15MHz; the gas pressure is 20-100Pa, such as 20Pa, 25Pa, 30Pa, 35Pa, 40Pa, 45Pa, 50Pa, 55Pa, 60Pa, 65Pa, 70Pa, 75Pa, 80Pa, 85Pa, 90Pa, 95Pa or 100Pa; The temperature is 300-500°C, such as 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C ℃, 440℃, 450℃, 460℃, 470℃, 480℃, 490℃ or 500℃; RF power is 3500~6000W, such as 3500W, 3600W, 3700W, 3800W, 3900W, 4000W, 4100W, 4200W, 4300W , 4400W, 4500W, 4600W, 4700W, 4800W, 4900W, 5000W, 5100W, 5200W, 5300W, 5400W, 5500W, 5600W, 5700W, 5800W, 5900W or 6000W; the deposition power is 38-70W, such as 38W, 39W, 4 ,41W,42W,43W,44W,45W,46W,47W,48W,49W,50W,51W,52W,53W,54W,55W,56W,57W,58W,59W,60W,61W,62W,63W,64W,65W , 66W, 67W, 68W, 69W or 70W.

Preferably, the flow ratio of silane and hydrogen in step (5) is 1: (6-10), for example, it can be 1:6, 1:6.5, 1:7, 1:7.5, 1:8, 1:8.5 , 1:9, 1:9.5 or 1:10.

Preferably, the frequency of the plasma-enhanced chemical vapor deposition equipment is 12-16MHz, such as 12MHz, 12.5MHz, 13MHz, 13.5MHz, 14MHz, 14.5MHz, 15MHz, 15.5MHz or 16MHz; the gas pressure is 100-300Pa , such as 100Pa, 110Pa, 120Pa, 130Pa, 140Pa, 150Pa, 160Pa, 170Pa, 180Pa, 190Pa, 200Pa, 210Pa, 220Pa, 230Pa, 240Pa, 250Pa, 260Pa, 270Pa, 280Pa, 290Pa or 300Pa; 300°C, such as 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C . , 4600W, 4700W, 4800W, 4900W, 5000W, 5100W, 5200W, 5300W, 5400W, 5500W, 5600W, 5700W, 5800W, 5900W or 6000W; the deposition power is 38-70W, such as 38W, 39W, 40W, 41W, 42W ,43W,44W,45W,46W,47W,48W,49W,50W,51W,52W,53W,54W,55W,56W,57W,58W,59W,60W,61W,62W,63W,64W,65W,66W,67W , 68W, 69W or 70W.

Before coating the silicon wafers of solar cells, the silicon wafers need to be pre-treated, including cleaning and etching the silicon wafers, preparing PN junctions, plasma etching to remove the PN around the silicon wafers, and cleaning to remove the phospho-silicate glass. step. After the above-mentioned treatment, the surface of the silicon wafer is coated. The plasma-enhanced chemical vapor deposition equipment used in the present invention uses microwaves or radio frequencies to ionize the gas containing the constituent atoms of the film to form a highly chemically active layer locally. The plasma is used to deposit a thin film on a silicon substrate, and the precise control of the thickness of the deposited film can be achieved through the proportional control of the gas flow. In addition, the requirements of the present invention for the frequency, pressure, temperature, radio frequency power and deposition power of the equipment are all in the conventional range, the conditions are relatively mild, and it is easy to popularize and apply.

Compared with the prior art, the present invention at least has the following beneficial effects:

The solar cell anti-reflection film of the invention comprises a silicon nitride oxide thin film layer, a nano-titanium dioxide layer, a silicon nitride layer, a silicon dioxide layer and an amorphous silicon layer successively stacked and deposited on the surface of a silicon wafer. The preparation method of the solar anti-reflection film of the present invention comprises passing silicon wafer, silicon hydrogen compound and nitrogen gas into the plasma enhanced chemical vapor deposition equipment to deposit a silicon nitride oxide film layer on the surface of the silicon wafer, and then feeding nano titanium dioxide and inert gas The step of depositing a nano-titanium dioxide layer, then passing through silane and ammonia gas to deposit a silicon nitride layer, then passing through silicon dioxide to deposit a silicon dioxide layer, and finally passing through silane and hydrogen gas to deposit an amorphous silicon layer. The present invention adopts a multi-layer film, which can have the effect of anti-reflection on multiple specific wavelengths at the same time, and the thickness and refractive index of the film of the present invention are controllable, so that it can simultaneously play a better anti-reflection effect on multiple light energies of different wavelengths. Effect. In addition, the present invention uses microwaves or radio frequencies to ionize the gas containing the constituent atoms of the film, locally forming plasma with extremely high chemical activity, thereby depositing a film on the silicon substrate, and realizing the control of the deposited film by controlling the gas flow rate Precise control of thickness. The preparation method itself requires the frequency, pressure, temperature, radio frequency power and deposition power of the equipment to be in the conventional range, the conditions are relatively mild, it is easy to promote and apply, and the market prospect is broad.

Detailed ways

The technical solutions of the present invention will be further described below through specific embodiments. It should be clear to those skilled in the art that the embodiments are only for helping to understand the present invention, and should not be regarded as specific limitations on the present invention.

Example 1

In this embodiment, the following method is used to prepare the anti-reflection film of the solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:1:1; the frequency of the plasma-enhanced chemical vapor deposition equipment is 12MHz; the gas pressure is 20Pa; the temperature is 100°C; the radio frequency power is 3500W; the deposition power is 38W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma-enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:10; The frequency of the plasma enhanced chemical vapor deposition equipment is 10MHz; the gas pressure is 20Pa; the temperature is 150°C; the radio frequency power is 3500W; the deposition power is 50W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:3; the plasma The frequency of the enhanced chemical vapor deposition equipment is 12MHz; the gas pressure is 100Pa; the temperature is 100°C; the radio frequency power is 3500W; the deposition power is 38W;

(4) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 10MHz; the gas pressure is 20Pa ; The temperature is 300°C; the RF power is 3500W; the deposition power is 38W;

(5) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:6; the plasma The frequency of the enhanced chemical vapor deposition equipment is 12MHz; the gas pressure is 100Pa; the temperature is 100°C; the radio frequency power is 3500W; and the deposition power is 38W.

Example 2

In this embodiment, the following method is used to prepare the anti-reflection film of the solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:4:3; the frequency of the plasma-enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 80Pa; the temperature is 300°C; the radio frequency power is 6000W; the deposition power is 70W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:25; The frequency of the plasma-enhanced chemical vapor deposition equipment is 13MHz; the gas pressure is 100Pa; the temperature is 350°C; the radio frequency power is 6000W; the deposition power is 80W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:6; the plasma The frequency of the enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 300Pa; the temperature is 300°C; the radio frequency power is 6000W; the deposition power is 70W;

(4) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 15MHz; the gas pressure is 100Pa ; The temperature is 500°C; the RF power is 6000W; the deposition power is 70W;

(5) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:10; the plasma The frequency of the enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 300Pa; the temperature is 300°C; the radio frequency power is 6000W; and the deposition power is 70W.

Example 3

In this embodiment, the following method is used to prepare the anti-reflection film of the solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:2:1.5; the frequency of the plasma-enhanced chemical vapor deposition equipment is 14MHz; the gas pressure is 50Pa; the temperature is 200°C; the radio frequency power is 4250W; the deposition power is 54W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:17.5; The frequency of the plasma-enhanced chemical vapor deposition equipment is 11.5MHz; the gas pressure is 60Pa; the temperature is 250°C; the radio frequency power is 4250W; the deposition power is 65W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:4.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 14MHz; the gas pressure is 200Pa; the temperature is 200°C; the radio frequency power is 4250W; the deposition power is 54W;

(4) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 22.5MHz; the gas pressure is 60Pa; temperature is 400°C; RF power is 4250W; deposition power is 54W;

(5) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:8; the plasma The frequency of the enhanced chemical vapor deposition equipment is 14MHz; the gas pressure is 200Pa; the temperature is 200°C; the radio frequency power is 4250W; and the deposition power is 54W.

Example 4

In this embodiment, the following method is used to prepare the anti-reflection film of the solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:1:1; the frequency of the plasma-enhanced chemical vapor deposition equipment is 13MHz; the gas pressure is 30Pa; the temperature is 105°C; the radio frequency power is 3600W; the deposition power is 40W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma-enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:20; The frequency of the plasma enhanced chemical vapor deposition equipment is 12MHz; the gas pressure is 50Pa; the temperature is 200°C; the radio frequency power is 4000W; the deposition power is 50W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 15MHz; the gas pressure is 150Pa; the temperature is 200°C; the radio frequency power is 4000W; the deposition power is 40W;

(4) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 10MHz; the gas pressure is 50Pa ; The temperature is 300°C; the RF power is 3500W; the deposition power is 42W;

(5) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:8; the plasma The frequency of the enhanced chemical vapor deposition equipment is 12MHz; the gas pressure is 100Pa; the temperature is 100°C; the radio frequency power is 5000W; and the deposition power is 40W.

Example 5

In this embodiment, the following method is used to prepare the anti-reflection film of the solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:2:3; the frequency of the plasma-enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 80Pa; the temperature is 280°C; the radio frequency power is 5500W; the deposition power is 58W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:25; The frequency of the plasma enhanced chemical vapor deposition equipment is 11MHz; the gas pressure is 60Pa; the temperature is 200°C; the radio frequency power is 4500W; the deposition power is 50W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:5.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 13MHz; the gas pressure is 200Pa; the temperature is 200°C; the radio frequency power is 4500W; the deposition power is 60W;

(4) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 10MHz; the gas pressure is 60Pa ; The temperature is 300°C; the RF power is 4500W; the deposition power is 45W;

(5) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:7.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 15MHz; the gas pressure is 300Pa; the temperature is 100°C; the radio frequency power is 5500W; and the deposition power is 50W.

Comparative example 1

The solar cell anti-reflection film described in the invention is prepared by the method for preparing the solar cell anti-reflection film disclosed in CN104241402A.

Comparative example 2

The solar cell anti-reflection film described in the invention is prepared by adopting the preparation method of the solar cell anti-reflection film disclosed in CN101989623A.

Comparative example 3

This comparative example adopts the following method to prepare the anti-reflection film of solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:2:3; the frequency of the plasma-enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 80Pa; the temperature is 280°C; the radio frequency power is 5500W; the deposition power is 58W;

(2) Continue to feed nano-titanium dioxide and inert gas in the plasma enhanced chemical vapor deposition equipment, so that nano-titanium dioxide is deposited on the surface of the silicon oxynitride film layer; the flow ratio of described nano-titanium dioxide and inert gas is 1:25; The frequency of the plasma enhanced chemical vapor deposition equipment is 11MHz; the gas pressure is 60Pa; the temperature is 200°C; the radio frequency power is 4500W; the deposition power is 50W;

(3) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:5.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 13MHz; the gas pressure is 200Pa; the temperature is 200°C; the radio frequency power is 4500W; and the deposition power is 60W.

Comparative example 4

This comparative example adopts the following method to prepare the anti-reflection film of solar cell:

(1) feed silicon chip, silicon hydride and nitrogen in the plasma enhanced chemical vapor deposition equipment, make the surface deposition silicon oxynitride thin film of described silicon chip; The flow ratio of described silicon chip, silicon hydride and nitrogen is: 1:2:3; the frequency of the plasma-enhanced chemical vapor deposition equipment is 16MHz; the gas pressure is 80Pa; the temperature is 280°C; the radio frequency power is 5500W; the deposition power is 58W;

(2) Continue to feed silane and ammonia in the plasma enhanced chemical vapor deposition equipment, so that silicon nitride is deposited on the surface of the nano-titanium dioxide layer; the flow ratio of the silane and ammonia is 1:5.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 13MHz; the gas pressure is 200Pa; the temperature is 200°C; the radio frequency power is 4500W; the deposition power is 60W;

(3) Continue to feed silicon dioxide in the plasma-enhanced chemical vapor deposition equipment, so that silicon dioxide is deposited on the surface of the silicon nitride layer; the frequency of the plasma-enhanced chemical vapor deposition equipment is 10MHz; the gas pressure is 60Pa ; The temperature is 300°C; the RF power is 4500W; the deposition power is 45W;

(4) Continue to feed silane and hydrogen in the plasma-enhanced chemical vapor deposition equipment, so that the amorphous silicon layer is deposited on the surface of the silicon dioxide layer; the flow ratio of the silane and hydrogen is 1:7.5; the plasma The frequency of the enhanced chemical vapor deposition equipment is 15MHz; the gas pressure is 300Pa; the temperature is 100°C; the radio frequency power is 5500W; and the deposition power is 50W.

Performance Testing:

The refractive index test adopts the SE400adv ellipsometer produced by SENTECH;

The reflectivity adopts the PELAMBDA integral reflectometer produced by PE Company;

Thickness uniformity uses the thickness range of five points on the anti-reflection film to evaluate the uniformity of its thickness. The larger the range, the worse the uniformity:

Range = maximum value - minimum value.

The results of all the tests are shown in Table 1. It can be seen that the average reflectance of the anti-reflection film of the present invention is greatly reduced compared with the comparative example, and the refractive index effect is also better; and the uniformity of the film thickness is extremely poor. It fluctuates at 1-2nm, indicating that the thickness uniformity effect is very good.

Table 1 performance test results

average refractive index Average reflectance (%) Thickness uniformity (nm) Example 1 2.03 1.51 1 Example 2 2.21 3.22 2 Example 3 2.16 3.63 1 Example 4 2.24 9.04 2 Example 5 2.18 8.32 2 Comparative example 1 2.06 21.6 8 Comparative example 2 2.34 23.5 9 Comparative example 3 2.21 20.9 6 Comparative example 4 2.30 21.5 8

The applicant declares that the present invention illustrates the process method of the present invention through the above examples, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of the selected raw materials in the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention.

Claims (10)

1. a solar battery antireflective film, is characterized in that, comprises silicon oxynitride film layer, nanometer titanium dioxide layer, silicon nitride layer, silicon dioxide layer and amorphous silicon layer that superposition is successively deposited on silicon chip surface.

2. solar battery antireflective film according to claim 1, is characterized in that, the thickness of described silicon oxynitride film layer is 25 ~ 30nm, and refractive index is 2.15 ~ 2.36;

Preferably, the thickness of described nanometer titanium dioxide layer is 28 ~ 32nm, and refractive index is 2.1 ~ 2.2;

Preferably, the thickness of described silicon nitride layer is 35 ~ 42nm, and refractive index is 2.2 ~ 2.4;

The thickness of described silicon dioxide layer is 45 ~ 55nm, and refractive index is 1.4 ~ 1.55.

3. solar battery antireflective film according to claim 1 and 2, is characterized in that, in described silicon oxynitride film layer, the granularity of silicon oxynitride is 12 ~ 15.5nm;

Preferably, in described nanometer titanium dioxide layer, the granularity of nano titanium oxide is 8 ~ 12nm;

Preferably, in described silicon nitride layer, the granularity of silicon nitride is 10 ~ 15nm;

Preferably, in described silicon dioxide layer, the granularity of silicon dioxide is 20 ~ 25nm.

4. according to the solar battery antireflective film one of claims 1 to 3 Suo Shu, it is characterized in that, the thicknesses of layers of described silicon oxynitride film layer, nanometer titanium dioxide layer, silicon nitride layer, silicon dioxide layer and amorphous silicon layer increases successively.

5., according to the preparation method of the solar battery antireflective film one of Claims 1 to 4 Suo Shu, it is characterized in that, comprise the steps:

(1) in plasma enhanced chemical vapor deposition equipment, pass into silicon chip, hydrosilicon and nitrogen, make the surface deposition silicon oxynitride film of described silicon chip;

(2) continue in plasma enhanced chemical vapor deposition equipment, pass into nano titanium oxide and inert gas, make nano titanium oxide be deposited on the surface of silicon oxynitride film layer;

(3) continue in plasma enhanced chemical vapor deposition equipment, pass into silane and ammonia, make nitride deposition on the surface of nanometer titanium dioxide layer;

(4) continue to pass into silicon dioxide in plasma enhanced chemical vapor deposition equipment, make silica deposit on the surface of silicon nitride layer;

(5) continue in plasma enhanced chemical vapor deposition equipment, pass into silane and hydrogen, make amorphous silicon layer be deposited on the surface of silicon dioxide layer.

6. preparation method according to claim 5, is characterized in that, the flow-rate ratio of step (1) described silicon chip, hydrosilicon and nitrogen is 1:(1 ~ 4): (1 ~ 3);

Preferably, the frequency of described plasma enhanced chemical vapor deposition equipment is 12 ~ 16MHz; Gas pressure intensity is 20 ~ 80Pa; Temperature is 100 ~ 300 DEG C; Radio-frequency power is 3500 ~ 6000W; Deposition power is 38 ~ 70W.

7. the preparation method according to claim 5 or 6, is characterized in that, step (2) described inert gas is the mixture of any one or at least two kinds in neon, argon gas or helium;

Preferably, the flow-rate ratio of described nano titanium oxide and inert gas is 1:(10 ~ 25);

Preferably, the frequency of described plasma enhanced chemical vapor deposition equipment is 10 ~ 13MHz; Gas pressure intensity is 20 ~ 100Pa; Temperature is 150 ~ 350 DEG C; Radio-frequency power is 3500 ~ 6000W; Deposition power is 50 ~ 80W.

8. according to the preparation method one of claim 5 ~ 7 Suo Shu, it is characterized in that, the flow-rate ratio of step (3) described silane and ammonia is 1:(3 ~ 6);

Preferably, the frequency of described plasma enhanced chemical vapor deposition equipment is 12 ~ 16MHz; Gas pressure intensity is 100 ~ 300Pa; Temperature is 100 ~ 300 DEG C; Radio-frequency power is 3500 ~ 6000W; Deposition power is 38 ~ 70W.

9. according to the preparation method one of claim 5 ~ 8 Suo Shu, it is characterized in that, in step (4), the frequency of described plasma enhanced chemical vapor deposition equipment is 10 ~ 15MHz; Gas pressure intensity is 20 ~ 100Pa; Temperature is 300 ~ 500 DEG C; Radio-frequency power is 3500 ~ 6000W; Deposition power is 38 ~ 70W.

10. according to the preparation method one of claim 5 ~ 9 Suo Shu, it is characterized in that, the flow-rate ratio of step (5) described silane and hydrogen is 1:(6 ~ 10);

Preferably, the frequency of described plasma enhanced chemical vapor deposition equipment is 12 ~ 16MHz; Gas pressure intensity is 100 ~ 300Pa; Temperature is 100 ~ 300 DEG C; Radio-frequency power is 3500 ~ 6000W; Deposition power is 38 ~ 70W.