CN106653872B - A kind of solar cell of anti-PID effects - Google Patents

Abstract

The present invention relates to a kind of solar cells of anti-PID effects, it includes crystalline silicon substrate, matte, diffusion emitter knot and four layers of passivated reflection reducing being sequentially deposited in crystalline silicon substrate and penetrates film, and first layer is amorphous silicon layer, and thickness is 5 8nm, the second layer is SiNx, refractive index is 2.25 2.35, and thickness is 6 9nm, and the refractive index of third layer SiNx is 1.95 2.05, thickness is 60 70nm, 4th layer is aluminium oxide, and refractive index is 1.75 1.85, and thickness is 3 9nm.The anti-PID effects effect of the present invention is good, and can be produced on the basis of conventional silicon nitride filming equipment, at low cost.

Description

A kind of anti-PID effect solar cell

technical field

The invention relates to the field of solar cells, in particular to a solar cell resistant to PID effect.

Background technique

Crystalline silicon solar cells do not emit or emit any harmful substances during use; there are no moving parts, no noise, light weight, small size, modular features, can be dispersed and set up on site, the construction period is short, and the working life is long 20-25 Years, easy maintenance, reliable operation and other advantages, it is a very ideal renewable clean energy. In practical applications, because the output voltage and power of a single crystalline silicon solar module are too low to meet the needs of life or production, multiple modules need to be connected in series. Under the condition that the outer frame is grounded, multiple components connected in series will result in high reverse bias voltage between the outer frame and the surface of the cell.

In long-term use, hot and humid environments are unavoidable, and these extreme conditions combine to form the PID (Potential Induced Degradation, potential-induced decay) test conditions, that is, the bias voltage of the cell to the frame is 1000V, 85°C and 85% Relative humidity, the test time is generally 100h. The PID effect mainly refers to the fact that under the conditions of high bias voltage, high temperature, and high humidity, the metal ions in the soda-lime glass, the packaging material on the surface of the module, move to the surface of the cell, and form local aggregation on the surface of the cell, which makes the cell fail. effect. At present, it is mainly believed that the PID effect can be eliminated by changing the grounding method of the components, replacing the packaging material of the cell components, and developing anti-PID cells.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a solar cell with anti-PID effect.

In order to solve the above problems, the technical solution adopted in the present invention is: a kind of anti-PID solar cell, including silicon wafer, suede, diffusion emission junction and electrode, it is characterized in that, there are four layers of passivation on the surface of the diffusion emission junction Anti-reflection coating, the first layer is amorphous silicon layer with a thickness of 5-8nm, the second layer is SiNx with a refractive index of 2.25-2.35 and a thickness of 6-9nm, and the third layer of SiNx has a refractive index of 1.95-2.05 , the thickness is 60-70nm, the fourth layer is aluminum oxide, the refractive index is 1.75-1.85, and the thickness is 3-9nm.

Preferably, the amorphous silicon layer is a film prepared by tube or plate plasma chemical vapor deposition.

Preferably, the SiNx is a film prepared by tube or plate plasma chemical vapor deposition.

Preferably, the aluminum oxide is aluminum oxide prepared by plasma enhanced chemical vapor deposition or atomic layer deposition.

Preferably, the silicon wafer is a polycrystalline silicon wafer.

Preferably, the first layer is an amorphous silicon layer with a thickness of 7nm; the second layer is SiNx with a refractive index of 2.3 and a thickness of 9nm; the third layer of SiNx has a refractive index of 2.0 and a thickness of 65nm; the fourth layer It is aluminum oxide with a refractive index of 1.8 and a thickness of 4nm.

Compared with the traditional crystalline silicon solar cell, the solar cell of the present invention adds an anti-PID effect layer deposited on the light-transmitting layer, and effectively eliminates the PID effect through reasonable matching of the material, refractive index and thickness of each film layer .

Description of drawings

Fig. 1 is a schematic structural diagram of a solar cell resistant to PID effect according to the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with specific embodiments and accompanying drawings.

Example 1:

The preparation method of a kind of anti-PID effect solar cell of the present invention is as follows:

Step 1, preheating, the crystalline silicon substrate enters the reaction chamber and is heated at a constant temperature, so that the temperature reaches the set reaction temperature of 400-500°C;

Step 2, the first layer of amorphous silicon film is deposited, the flow rate of NH3 is set to 0, the flow rate of SiH4 is set to 1800 sccm, and the time is set to 15s to form a 5-8nm anti-PID dense amorphous silicon layer 2 on the surface of the silicon wafer 1

Step 3, the second layer of film deposition, feed the reaction gas NH3 and SiH4, SiH4 flow rate 500-1000 sccm/min, NH3 flow rate 1000-4000 sccm/min, keep constant pressure, pressure range 0.5-1.5Torr, coating time 100 ~150s;

Step 3, the third layer of thin film is deposited, the reaction gas is directly introduced into the reaction chamber, the flow rate of SiH4 is 500-1000 sccm/min, the flow rate of NH3 is 6000-7000 sccm/min, the pressure range is 1.0-2.0 Torr, and the coating time is 250s-500s;

Step 4, the fourth layer of aluminum oxide thin film is deposited, and the aluminum oxide thin film is prepared by atomic layer deposition.

The present invention is a kind of anti-PID effect solar cell, as shown in Figure 1, it comprises silicon chip 5, suede surface, diffusion emission junction and electrode, there are four layers of passivation anti-reflection film on the surface of described diffusion emission junction, the first One layer is amorphous silicon layer 4 with a thickness of 5nm, the second layer is SiNx3 with a refractive index of 2.35 and a thickness of 6nm, the third layer of SiNx2 has a refractive index of 2.05 and a thickness of 70nm, and the fourth layer is aluminum oxide 1, The refractive index is 1.85 and the thickness is 9nm.

Example 2

The present invention is a kind of anti-PID effect solar cell, including silicon chip, suede, diffusion emitting junction and electrode, there are four layers of passivation anti-reflection film on the surface of emitting junction, the first layer is amorphous silicon layer, the thickness is 7nm , the second layer is SiNx with a refractive index of 2.3 and a thickness of 9nm, the third layer of SiNx has a refractive index of 2.0 and a thickness of 65nm, and the fourth layer is aluminum oxide with a refractive index of 1.8 and a thickness of 4nm.

Example 3

The invention is a kind of anti-PID effect solar cell, including silicon chip, suede, diffusion emitting junction and electrode, there are four passivation anti-reflection films on the surface of emitting junction, the first layer is an amorphous silicon layer with a thickness of 8nm , the second layer is SiNx with a refractive index of 2.25 and a thickness of 7nm, the third layer of SiNx has a refractive index of 1.95 and a thickness of 60nm, and the fourth layer is aluminum oxide with a refractive index of 1.75 and a thickness of 3nm.

comparative example

A kind of anti-PID effect solar cell, comprises silicon wafer, textured surface, diffusion emitter junction and electrode, has one deck passivation anti-reflection film SiNx on the surface of emitter junction, the refractive index of described anti-reflection film SiNx is 2.0-2.1, film The thickness is 80-90nm.

The battery sheets of the above-mentioned comparative examples and examples were packaged into modules with the same packaging material, and after PID was performed for 96 hours under a bias voltage of -1000V, the results were as follows:

experimental status Power before PID/W Power after PID/W attenuation comparative example 248.1 198.4 20% Example 1 248.1 243.3 1.85% Example 2 248 243 2.00% Example 3 248 242.8 2.10%

The test data after PID96h is less than 5%, indicating that the use of this coating process has completely eliminated the PID effect.

Compared with the traditional crystalline silicon cell, the battery of the present invention adds an anti-PID effect layer deposited on the light-transmitting layer, and effectively eliminates the PID effect through reasonable matching of each film layer, material, refractive index and thickness.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (1)

1. a kind of solar cell of anti-PID effects, including silicon chip, matte, diffusion emitter knot and electrode, which is characterized in that The diffusion emitter knot surface has four layers of passivated reflection reducing to penetrate film, and first layer is amorphous silicon layer, thickness 5-8nm, and the second layer is The refractive index of SiNx, refractive index 2.25-2.35, thickness 6-9nm, third layer SiNx are 1.95-2.05, thickness 60- 70nm, the 4th layer is aluminium oxide, refractive index 1.75-1.85, thickness 3-9nm, the amorphous silicon layer be using tubular type or The film that board-like plasma chemical vapor deposition process is prepared, the SiNx are using tubular type or board-like plasma chemical gas The film that phase deposition method is prepared, the aluminium oxide are plasma enhanced chemical vapor deposition method or atomic layer deposition method The aluminium oxide being prepared, the silicon chip are polysilicon chip, and the first layer is amorphous silicon layer, and thickness 7nm, the second layer is SiNx, refractive index 2.3, it is aluminium oxide that the refractive index of thickness 9nm, third layer SiNx, which are 2.0, thickness 65nm, the 4th layer, Refractive index is 1.8, thickness 4nm.