KR101256810B1 - Inspection apparatus and method of solar cell using electro luminescense - Google Patents

Abstract

PURPOSE: A solar cell inspecting device using an EL method and a method thereof are provided to photographs images of light emitting of a solar cell by using a band pass filter, thereby accurately inspecting defects of the solar cell. CONSTITUTION: A solar cell inspecting device comprises a band pass filter and a filter rotating member(104). The band pass filter transmits lights of a predetermined wavelength range among the lights emitted by a silicon solar cell. The filter rotating member is installed in the upper part of the solar cell or the lower part of the photographing member. The band pass filter is mounted in the filter rotating member, and the filter rotating member rotates the band pass filter.

Description

Solar cell inspection apparatus and method using EL technique {INSPECTION APPARATUS AND METHOD OF SOLAR CELL USING ELECTRO LUMINESCENSE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell inspection apparatus and method using an EL technique, and in particular, a polycrystalline silicon substrate using a band pass filter that transmits light of a certain wavelength range among light emitted from a solar cell. The present invention relates to a solar cell inspection apparatus and method using an EL technique for inspecting a defect of a solar cell based on a).

Today, due to the finiteness of fossil fuels, there is a growing interest in developing alternative energy. A typical alternative energy is a solar cell capable of generating electrical energy using solar energy, a clean energy source.

Such a solar cell is a device that converts sunlight directly into electricity, and is basically a diode made of a p-n junction.

Such a solar cell is a solar cell produced on the basis of a single crystal silicon substrate, a solar cell produced on the basis of a polycrystalline silicon substrate, as shown in Figure 1, Figure 1 is a single crystal silicon solar cell according to an embodiment of the present invention and Figure shows a polycrystalline silicon solar cell.

In general, after a solar cell is produced based on a monocrystalline silicon substrate or a polycrystalline silicon substrate, the solar cell undergoes a procedure of inspecting quality information before shipping the product.

At this time, the EL (Electro luminescence) image acquisition test method is mainly used for the quality inspection method of the solar cell, and the EL image acquisition inspection method checks the quality of the solar cell by using characteristics that generate light when the solar cell is powered. That's the way it is.

However, when a solar cell is produced using a single crystal silicon substrate, as shown in FIG. 1A, the surface of the single crystal silicon substrate is uniform, which makes it difficult to detect defects such as cracks generated in the solar cell. Does not follow

However, there is a problem in that it is difficult to commercialize the solar cell due to the increase in material cost to produce the solar cell as a single crystal silicon substrate.

To overcome this problem, solar cells are produced using a polycrystalline silicon substrate. However, in this case, as shown in FIG. There is a problem that is difficult to evaluate the quality of the solar cell is difficult.

The present invention has been made to solve the above-mentioned problems, using a bandpass filter that transmits light in a wavelength range longer than the wavelength longer than a certain length at a wavelength of the maximum light intensity emitted from the solar cell. By taking the light emitting image of the solar cell, the light intensity of the light emitting image of the solar cell is filtered to the maximum wavelength part, so that the contrast between the defective part of the solar cell and the business card of the normal part is relatively clear, so that the defect of the solar cell can be accurately inspected. It is an object of the present invention to provide a solar cell inspection apparatus and method using an EL technique.

In addition, the present invention by taking a light emitting image of the solar cell using a band pass filter that transmits light in a certain wavelength range of the light emitted from the solar cell, by removing the noise that can occur in the light of a relatively long wavelength range It is an object of the present invention to provide a solar cell inspection apparatus and method that can accurately inspect the defect of the cell.

In addition, the present invention by taking a light-emitting image of the solar cell when using a band pass filter having a different wavelength range, respectively, and generates a synthesized image, to produce a band pass filter corresponding to a solar cell having a different surface for each manufacturer It is an object of the present invention to provide a solar cell inspection apparatus and method using an EL technique that can shoot the applied emission image to accurately inspect the defect of the solar cell.

In addition, the present invention has a filter rotation means that is equipped with a plurality of band pass filter having a different wavelength range of the light to be transmitted, the solar cell using an EL technique that can easily apply a variety of band pass filter to take a light emission image of the solar cell Its purpose is to provide an inspection apparatus and method.

In the solar cell inspection apparatus for applying a power to the silicon solar cell of the present invention for achieving the above object, by taking a light emitting image of the solar cell through a photographing means, to inspect the defect of the solar cell, A band pass filter for transmitting light of a wavelength range longer than a wavelength longer than a predetermined length at a wavelength at which the intensity of light emitted from a battery is relatively large, and installed at a lower end of the photographing means, and the band pass filter is mounted, and the band And filter rotation means for rotating the pass filter.

In the solar cell inspection apparatus for applying a power to the silicon solar cell of the present invention, by taking a light emitting image of the solar cell through a photographing means, and inspecting the defect of the solar cell, a predetermined amount of light emitted from the silicon solar cell A band pass filter for transmitting light in a wavelength range, and a filter rotation means installed at a lower end of the photographing means, and equipped with the band pass filter and rotating the band pass filter, wherein the minimum wavelength of the predetermined wavelength range is a solar cell. Is a wavelength longer than a certain length at a wavelength at which the intensity of the emitted light is relatively maximum.

The band pass filter may include a first band pass filter that transmits the entire wavelength range longer than the minimum wavelength of the predetermined wavelength range, and a second band pass filter that transmits the entire wavelength range shorter than the maximum wavelength of the predetermined wavelength range. will be.

In addition, the filter rotation means is provided with a plurality of the band pass filter, each band pass filter is different in the wavelength range of the transmitted light.

In the silicon solar cell inspection method of the present invention, the step of applying power to the solar cell, the light emitting image of the solar cell in the case of using a plurality of band pass filter each having a different wavelength range of the transmitted light is taken by the photographing means And generating an image obtained by synthesizing the plurality of photographed light emitting images.

According to the present invention, a photovoltaic cell is photographed using a band pass filter that transmits light having a wavelength range longer than a wavelength longer than a predetermined length at a wavelength at which the light emitted from the solar cell is relatively maximum. The wavelength portion of the light emitting image of the maximum light intensity is filtered to make the contrast of the business card of the defective part and the normal part of the solar cell relatively clear, thereby accurately inspecting the defect of the solar cell.

In addition, the present invention by taking a light emitting image of the solar cell using a band pass filter that transmits light in a certain wavelength range of the light emitted from the solar cell, by removing the noise that can occur in the light of a relatively long wavelength range The defect of the battery can be inspected accurately, and the inspection time of the solar cell can be reduced.

In addition, the present invention by taking a light-emitting image of the solar cell when using a band pass filter having a different wavelength range, respectively, and generates a synthesized image, to produce a band pass filter corresponding to a solar cell having a different surface for each manufacturer The applied light emitting image can be taken to accurately check the defect of the solar cell.

In addition, the present invention is provided with a filter rotation means is provided with a plurality of band pass filters having a different wavelength range of the light to be transmitted, there is an effect that can easily apply a variety of band pass filters to take a light emitting image of the solar cell.

1 is a view showing a single crystal silicon solar cell and a polycrystalline silicon solar cell according to an embodiment of the present invention,
2 is an internal configuration diagram of a solar cell inspection apparatus using the EL technique according to an embodiment of the present invention,
3 is a detailed configuration diagram of a solar cell supporting means using an EL technique according to an embodiment of the present invention,
4 is a block diagram of an apparatus for inspecting a solar cell using an EL technique according to an exemplary embodiment of the present invention;
Figure 5 is a graph showing the quantum efficiency of the solar cell according to an embodiment of the present invention,
6 is a flowchart illustrating a solar cell inspection process using an EL technique according to an embodiment of the present invention;
7 is a view showing a light emitting image of a solar cell for each manufacturer transmitted through a band pass filter for transmitting light of a predetermined wavelength range according to an embodiment of the present invention;
8 is a view showing a result of detecting a defect of the solar cell in the solar cell inspection apparatus using the EL technique according to an embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

2 is an internal configuration diagram of a solar cell inspection apparatus using an EL technique according to an embodiment of the present invention.

Solar cell inspection apparatus 100 is installed on the body 101, the solar cell support means 102 for supporting the solar cell in the body 101, the power supply to the solar cell inside the body 101 to block external light Filter rotation means 104 including a plurality of band pass filters having different wavelength ranges of light to be transmitted and positioned at a lower end corresponding to the photographing direction of the photographing means 103. It is configured to include).

In this case, the band pass filter mounted on the filter rotating means 104 is a band pass filter for transmitting light of a specific wavelength or more in a wavelength range longer than a wavelength long by a certain length at a wavelength at which the light emitted from the solar cell is relatively maximum. A plurality of bandpass filters may be mounted or a plurality of band pass filters for transmitting light of a predetermined wavelength range may be mounted.

On the other hand, as shown in FIG. 5, the wavelength of the light emitted from the solar cell of the single crystal silicon substrate has a maximum wavelength of 501, whereas the wavelength of the light emitted from the solar cell of the polycrystalline silicon substrate is the largest. Due to irregularities in the silicon substrate surface, two or more places such as 502 and 503 may be detected.

Therefore, in the band pass filter according to the embodiment of the present invention, the wavelength that is the maximum wavelength of the light emitted from the solar cell of the polycrystalline silicon substrate, that is, the wavelength corresponding to 502, is longer than the wavelength longer than a certain length by 502 wavelength so as not to appear in the emission image. Bandpass filters are used that transmit light of longer wavelengths (eg 1200 nm).

Therefore, it is preferable that the filter rotating means 104 is equipped with a plurality of band pass filters for transmitting light of different wavelengths among the wavelengths of 1200 nm or more, for example, 1200 nm, 1300 nm, 1400 nm, and the like. When the light emitting image of the solar cell is photographed and synthesized, an image except for the light intensity part of the light emitting image of the solar cell is obtained. It becomes clear and it becomes easy to detect a defect of a solar cell.

In addition, in order to simplify solar cell inspection, a band pass filter (for example, 1450 nm to 1550 nm) that transmits light of a certain wavelength range among wavelengths longer than 502 wavelength may be used to capture a light emitting image of the solar cell. The filter is produced by superimposing a first bandpass filter that transmits all light in a wavelength range longer than 1450 nm and a second bandpass filter that transmits all light in a wavelength range shorter than 1550 nm to transmit light between 1450 nm and 1550 nm. can do.

In this case, the filter rotation means 104 is equipped with a band pass filter having a different wavelength range, for example, a band pass filter of 1450 nm to 1550 nm, a band pass filter of 1550 nm to 1650 nm, and a band pass filter of 1650 to 1750 nm. In addition, the light emitting images of the solar cells passing through each band pass filter are taken and synthesized to detect defects of the solar cells.

In this case, even if the intensity of light emitted from the solar cell is relatively different depending on the manufacturer, it is possible to apply a band pass filter that matches the light emission characteristics of the solar cell, and can shoot the emission image of various wavelength ranges. This reduces the quality inspection time.

On the other hand, in the embodiment of the present invention has been described as an example that three band pass filters having different wavelength ranges are mounted on the filter rotation means 104, but is not limited to the number of band pass filters.

3 is a detailed configuration diagram of a solar cell support means using the EL technique according to an embodiment of the present invention.

The solar cell support means 102 includes a transparent support 105 on which a solar cell is placed, an upper probe portion into which positive (+) power flows in order to apply external power to the solar cell, and a lower probe into which negative (-) power flows. It includes a probe unit 130 having a portion.

That is, when the solar cell is placed on the transparent support 105, the solar cell support means 102 lowers the upper probe part so that the probe part contacts the upper and lower parts of the solar cell, and emits light by applying a voltage to the solar cell.

At this time, the solar cell emits light in the near infrared (750 ~ 2500nm) wavelength band.

4 is a block diagram of a solar cell inspection apparatus using an EL technique according to an embodiment of the present invention, Figure 5 is a graph showing the quantum efficiency of the solar cell according to an embodiment of the present invention.

The solar cell inspection apparatus 100 detects the solar cell corresponding to the camera unit 150 corresponding to the photographing unit 103, the filter rotating unit 160 corresponding to the filter rotating unit 104, and the solar cell supporting unit 102. The unit 120, the probe unit 130, and the power circuit unit 140 are included.

The solar cell detector 120 detects that the solar cell is placed on the transparent support 105, and transfers the solar cell detection signal to the controller 110 when the solar cell is raised.

The probe unit 130 includes an upper probe unit and a lower probe unit, and contacts the upper and lower parts of the solar cell to apply power to the solar cell.

The power circuit unit 140 represents a circuit for applying external power to the solar cell for electro luminescence of the solar cell, and applies power to the probe unit 130.

The camera unit 150 uses a near infrared camera (Shortwave Infrared rays) that can measure light in the near infrared (750 ~ 1800nm) band, and takes a light emitting image of the solar cell.

The filter rotating unit 160 is equipped with a plurality of band pass filters having different wavelength ranges of the light to be transmitted, and as shown in Figure 2 arranged in a plurality of band pass filters in a circular manner rotated clockwise or counterclockwise by the motor The light emitted from the solar cell passes through the band pass filter.

The controller 110 controls the overall operation of the solar cell inspection apparatus, and when the solar cell is placed on the transparent support 105, power is applied through the probe unit 130.

The controller 110 sequentially applies a plurality of band pass filters that transmit only light having a specific wavelength range through the filter rotating unit 160 to the front of the camera lens, thereby capturing a light emitting image of the solar cell.

Thereafter, the controller 110 synthesizes all of the photographed emission images and displays them on a display unit (not shown), and detects and displays defects such as cracks of the solar cells displayed on the synthesized emission images.

When the luminescent image passing through the plurality of band pass filters is acquired and synthesized, the sharpness of irregular portions of the solar cell formed of polycrystalline silicon is lowered, and the sharpness of defective parts such as cracks is increased, thereby making it easier to fix defects of the solar cell. You can check it.

In addition, the sharpness of the fingerlines that are not electrically connected among the fingerlines corresponding to the electric field layer of the polycrystalline silicon substrate constituting the solar cell may also increase to identify various defects of the solar cell.

6 is a flowchart illustrating a solar cell inspection process using the EL technique according to an embodiment of the present invention, Figure 7 is a view showing a light emitting image of a solar cell passing through a plurality of bandpass filters according to an embodiment of the present invention. 8 is a diagram illustrating a result of detecting a defect of a solar cell in a solar cell inspection apparatus using an EL technique according to an exemplary embodiment of the present invention.

6 to 8, when it is detected in step S501 that the solar cell is placed on the transparent support 105, the controller 110 applies power to the solar cell in step S502.

In addition, the control unit 110 irradiates infrared rays to the solar cell in step S503, photographs the first emission image emitted from the solar cell and transmitted through the first bandpass filter to obtain the emission image corresponding to FIG. 7A. do.

In addition, the controller 110 drives the motor of the filter rotating unit 160 to transmit light emitted from the solar cell through the second band pass filter in step S504, and second light emission that passes through the second band pass filter in step S505. Acquire an image.

At this time, the filter rotating unit 160 is equipped with a plurality of band pass filters having a wavelength range of different light as shown in Figure 2, so that the band pass filter is sequentially changed while rotating left and right.

In addition, the control unit 110 drives the motor of the filter rotating unit 160 to transmit the light emitted from the solar cell through the third band pass filter in step S506, and the third light emission passing through the third band pass filter in step S507. Acquire an image.

Thereafter, the controller 110 synthesizes the first to third light emitting images, acquires the light emitting images as shown in FIG. 8, displays them on the screen, and detects and displays defects of the solar cells found in the light emitting images in step S509. .

In this case, the reason for obtaining the emission image of the solar cell by applying a plurality of band pass filters is because the physical properties of the polycrystalline silicon substrate constituting the solar cell are different for each solar cell manufacturer, and thus the same band pass filter is applied for each solar cell manufacturer. If you do so, a completely different emission image is taken.

Therefore, by applying multiple bandpass filters that transmit light in a certain wavelength range, the light emitting image of the solar cell is photographed and synthesized. As the irregular surfaces are darkened and leveled, cracks become more sharp and the quality of the solar cell is improved. It becomes easy to inspect.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of illustration, It will be readily apparent that various substitutions, modifications, and alterations can be made herein.

100: solar cell inspection device 101: body
102: solar cell support means 103: photographing means
104: filter rotation means 105: transparent support
110: control unit 120: solar cell detection unit
130: probe 140: power circuit
150: camera unit 160: filter rotation unit

Claims (5)

In the solar cell inspection apparatus for applying a power to the silicon solar cell, and taking a light emission image of the solar cell through the photographing means, to inspect the defect of the solar cell,
A band pass filter that transmits light having a wavelength range longer than a wavelength longer than a wavelength that is relatively maximum than an intensity at an ambient wavelength by a silicon solar cell; And
The solar cell inspection apparatus is installed on the upper end of the solar cell and the lower end of the photographing means, the band pass filter is mounted, and the filter rotating means for rotating the band pass filter.
In the solar cell inspection apparatus for applying a power to the silicon solar cell, and taking a light emission image of the solar cell through the photographing means, to inspect the defect of the solar cell,
A band pass filter configured to transmit light having a predetermined wavelength range among the light emitted from the silicon solar cell;
Is installed at the lower end of the photographing means, the band pass filter is mounted, and includes a filter rotating means for rotating the band pass filter,
The minimum wavelength of the predetermined wavelength range of the solar cell inspection device, characterized in that the intensity of light emitted from the solar cell is a wavelength longer by a certain length at a wavelength relatively maximum than the intensity at the ambient wavelength.
The method of claim 2, wherein the predetermined wavelength range includes the minimum wavelength and the maximum wavelength relatively longer than the minimum wavelength,
The band pass filter includes a first band pass filter transmitting the entire wavelength range longer than the minimum wavelength and a second band pass filter transmitting the entire wavelength range shorter than the maximum wavelength.
The method of claim 2,
The filter rotation means is provided with a plurality of the band pass filter, each band pass filter is a solar cell inspection device, characterized in that the wavelength range of the light to transmit different.
In the silicon solar cell inspection method,
Applying power to the solar cell;
Photographing a light emitting image transmitted from the solar cell by using a photographing means using a plurality of band pass filters having different wavelength ranges of light to be transmitted;
Generating an image obtained by synthesizing the plurality of photographed emission images;
The band pass filter is a solar cell inspection method characterized in that the intensity of light emitted from the silicon solar cell transmits light in the wavelength range longer than the wavelength longer than the wavelength that is relatively maximum than the intensity at the ambient wavelength.

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