TW201401532A - Laser cutting device of thin film solar cell and the measurement method thereof - Google Patents

Abstract

The invention relates to a laser cutting device of a thin film solar cell and the measurement method thereof. It applies to a thin film solar cell panel with large measurement areas. The laser cutting device of the thin film solar cell comprises a base, at least one laser head and at least one probe scanner. The base is provided with a recess on its upper surface, and a worktable is arranged in the recess. A positioning guide post is traversed across the upper surface of the base at its two sides. The laser head is arranged on the front surface of the positioning guide post and used for injecting a laser beam to a specific position of the thin film solar cell panel to process cutting. The probe scanner is also disposed on the front surface of the positioning guide post and used to proceed with a depth cross-section measurement after the laser process. The invention also provides a measurement method which is used after the laser cutting process, and it can proceed with a real-time and region-wide depth cross-section measurement.

Description

Laser cutting device for thin film solar cell and measuring method thereof

The invention relates to a laser cutting device for a thin film solar cell and a measuring method thereof, in particular to a probe scanning step measurement (α-step) integrated with a laser cutting device for application to a large-area thin film solar cell panel. After the laser process, depth profile measurements can be performed in real time and throughout the area.

According to the general thin film solar cell, P-type (positive type), type I (essential) and N-type (negative type) semiconductor layer junctions with different conductivity properties are used as the main structure of light absorption and energy conversion; when sunlight is irradiated At the P/I/N junction, some of the electrons thus have enough energy to leave the atom and become free electrons, lose electron atoms and thus generate holes, and attract holes and electrons through the P-type semiconductor layer and the N-type semiconductor layer, respectively. Separating the positive and negative charges, a potential difference is generated at the outer ends of the junction, and an external circuit is connected to the conductive layer to allow electrons to pass through and recombine with the hole at the other end of the P/I/N junction. The current is generated and transmitted to the load via the wire, so the battery can generate electricity under illumination.

In general, thin-film solar cell processes must achieve better cutting and edge Isolation effects through appropriate micromachining tools; traditionally, solar cell cutting methods are Scribe and split ( Break), using a V-shaped grinding tool to draw a V-shaped cut on the battery sheet, and then manually cut the cross section; but this method can only draw a straight line, and reduce the actual contact area of the battery sheet, wasting material.
Generally, in the edge isolation method, a plasma etching method is used, that is, a neutral gas (such as oxygen) is split into ions and electrons, and a voltage source (radio frequency or microwave) is used to generate an electric field on the surface of the material. Although the effect of plasma etching is good, the price of equipment is relatively low, but the requirements for personnel are very high, and the etching process will cause certain damage to the surface of the battery sheet. If the interface of the P/N is damaged, it will also be lowered. The effective area; another method of edge isolation is to use the traditional sand blasting method, that is, to use a mask (MASK) to shield the areas that do not need to be sprayed, and to remove the film material by high-speed splashing particles. In turn, the effect of edge separation is achieved. However, this method leaves residual blasting powder, so an additional cleaning step is required; furthermore, the mechanical stress caused by the blasting process adversely affects the reliability of solar cell use.

Another micro-machining tool can achieve better cutting and edge isolation. It uses laser cutting to make the laser beam focus on the object to form a conical shape, so that its energy can be concentrated very small. On the surface, the object absorbs the laser beam, and the energy heats the material until the material melts and vaporizes; the cutting precision and repeatability of the laser are relatively high, the cutting speed is relatively fast, and the cutting line is thin and smooth.

Furthermore, in the process of the existing thin film solar cell, three laser cuttings are required, and the manufacturing process includes the following steps: first, a transparent conductive oxide (TCO) is formed on the glass or the metal substrate; The laser is used to strip the transparent conductive layer leaving the groove; in the third step, the thin film is plated on the transparent conductive layer by sputtering or plasma enhanced chemical vapor deposition (PECVD). In the fourth step, the ruthenium film which leaves the groove is removed by laser; the fifth step is performed for metallization; and the sixth step, the metal plating film which leaves the groove is removed by laser.

However, after the laser cutting process of the existing thin film solar cell, the cutting line measurement method used is an optical microscope inspection method, a probe scanning step measurement method, and an electron microscope inspection method. However, these methods still exist. Some shortcomings such as:

1. The optical line microscopic view shows the width of the cutting line, but it is not easy to see its depth.
2. The probe scanning step measurement method can only perform local measurement, and needs to be processed for subsequent test strips, which is time-consuming, less accurate, and easy to fragment.
3. The electron microscope inspection method can only perform local measurement, and the inspection process needs to be vacuumed, the use is expensive, and the operation is time-consuming and easy to fragment.

Now, the present inventors have made research and improvement of the cutting device of the conventional thin film solar cell and the measuring method thereof, and provide a laser cutting device for a thin film solar cell and a measuring method thereof, in order to achieve better practical value.

The main object of the present invention is to provide a probe scanning step measurement and a laser cutting device for integration into a large-area thin film solar panel laser process, which can perform depth profile measurement in real time and in all regions.

In order to achieve the main purpose and effect of the laser cutting device of the thin film solar cell of the present invention and the measuring method thereof, the laser cutting device of the thin film solar cell comprises: a base, the upper end surface of the base is provided with a groove, the concave A working platform is disposed on the slot, and a positioning guiding column is disposed on two sides of the upper end surface of the base; at least one laser head is disposed on the front end surface of the positioning guiding column for emitting the laser beam to the a specific position on the thin film solar cell panel for cutting; at least one probe scanner disposed on the front end surface of the positioning guide post on one side of the laser head after the laser process Used as a depth profile measurement.
As described above, in the laser cutting device for a thin film solar cell of the present invention, a moving device is disposed between the groove and the table, and the table can be moved back and forth with respect to the positioning guide column.

As described above, the laser cutting device of the thin film solar cell of the present invention, wherein the positioning guide column is provided with a linear motor and a propeller for moving the laser head and the probe to the left and right with respect to the positioning guide column.

As described above, the laser cutting device for a thin film solar cell of the present invention, wherein the probe scanner further comprises a lifting mechanism for the lifting and lowering operation of the probe.

Furthermore, the present invention provides a laser cutting measurement method for a thin film solar cell, wherein after each laser cutting, the probe scanner is lowered to the probe tip by the lifting mechanism. After the surface of the thin film solar cell panel, the probe scanner is moved toward the laser cutting line by the linear motor and the propeller provided in the positioning guiding column, and the probe passes through the laser cutting line. Obtaining the depth and width of the laser cutting line, and then raising the probe scanner by the lifting mechanism for the next coating and laser cutting, so in the process of the thin film solar cell, three kinds are obtained. Depth and width curve data for different laser cutting lines.
In summary, the present invention integrates the probe scanning step measurement with the laser cutting device, and has the following advantages in implementation:

1. It can be applied to the measurement of depth profile after the laser processing of large-area thin-film solar panel.
2. It can be measured in real time without waiting for the laser cutting process to completely end and then measure.
3. Depth profile measurements can be performed arbitrarily throughout the region to improve existing fragmentation for local measurements.
4. In the process, no additional processing of the fragments is required for depth profile measurement, which saves time and costs.
5. The correction factor can be modified to perform depth correction. For example, after each laser cutting of a solar cell panel of different materials, the error between the probe scanning step measurement data and the electron microscope measurement data is compared to define a correction. The factor allows the probe scan step measurement value to correspond to the electron microscope measurement value to correct the depth value measured by the laser cutting line.

For a more complete and clear disclosure of the technical means, the object of the invention and the effect of the present invention, the following is a detailed description of the present invention.
First, referring to the first figure, a perspective view of a laser cutting device for a thin film solar cell of the present invention, the laser cutting device of the thin film solar cell includes: a pedestal (1), the pedestal (1) The upper end surface is provided with a groove, and the groove is provided with a working table (2), wherein the working table can be provided with an enlarged area thin film solar cell panel (7), and a set between the working table (2) and the groove is provided The moving device (6) can move the table (2) back and forth relative to the laser head (4) on the positioning guide column (3) (refer to the second figure) to facilitate the laser head (4) The laser beam emitted from the laser solar cell panel (7) is cut, and a positioning guide post (3) is disposed on two sides of the upper end surface of the base (1), and a straight line is disposed in the positioning guide post (3) a motor and a propeller (not shown) for moving the laser head (4) and the probe scanner (5) to the left and right relative to the positioning guide post (3); at least one laser head (4), The laser head (4) is set in the set a front end face of the guide post (3) for emitting a laser beam to a specific position on the thin film solar cell panel (7) for cutting; at least one probe scanner (5), the probe scanner (5) The front end surface of the positioning guide column (3) is disposed on one side of the laser head (4), and is used as a laser cutting line depth profile measurement after the laser process.

As described above, in a preferred embodiment of the present invention, the moving device (6) may further comprise a linear motor and a propeller different from the aforementioned linear motor and thruster disposed within the positioning guide post (3).

Referring again to the third and fourth figures, a partial enlarged view of the front and rear elevation of the probe scanner of the present invention, wherein the probe scanner (5) further includes a lifting mechanism (51) for the The probe scanner (5) performs a lifting operation to bring the probe into contact with the surface of the panel for instantaneous and full-area depth profile measurement to obtain depth and width curve data of the laser cutting line.

As described above, the laser cutting device for a thin film solar cell of the present invention, wherein the elevating mechanism (51) is an elevating motor.

Referring to FIG. 5 again, it is a flow chart of a laser cutting measurement method for a thin film solar cell of the present invention. The laser cutting measurement method of the thin film solar cell is performed after each laser cutting, and the measuring method steps include :

In a first step (S1), the probe scanner is lowered by the lifting mechanism to the probe tip to contact the surface of the thin film solar cell panel;

In a second step (S2), the probe scanner is moved toward the laser cutting line by the linear motor and the propeller provided in the positioning guide column;

In the third step (S3), when the probe moves through the laser cutting line, the curve of the depth and width of the laser cutting line can be obtained because the tip of the probe is lowered along with the surface of the cutting line;

Then, the probe scanner is lifted by the lifting mechanism for the next coating and laser cutting, so that the depth and width curves of three different laser cutting lines can be obtained in the process of the thin film solar cell. .

Furthermore, the laser cutting measurement method of the thin film solar cell of the present invention can perform depth correction by using a correction factor mode, for example, scanning the step measurement data of the probe after each laser cutting of a solar cell panel of different materials. Comparing with the error of the electron microscope measurement data, a correction factor is defined, so that the probe scanning step measurement value can be corresponding to the electron microscope measurement value, and used to correct the depth measured by the laser cutting line. Value.

Therefore, the present invention integrates the probe scanning step measurement with the laser cutting device, and can be applied to the large-area thin film solar cell panel laser process, and the depth profile measurement can be performed instantaneously and regionally, not only It also saves costs.

The above-mentioned embodiments or the drawings are not intended to limit the structure or the dimensions of the present invention, and any suitable changes or modifications may be made without departing from the scope of the invention.

In summary, the embodiments of the present invention can achieve the expected use efficiency, and the specific structure disclosed therein has not been seen in similar products, nor has it been disclosed before the application, and has completely complied with the provisions of the Patent Law. And the request, the application for the invention of a patent in accordance with the law, please forgive the review, and grant the patent, it is really sensible.

(1). . . Pedestal

(2). . . Workbench

(3). . . Positioning guide column

(4). . . Laser head

(5). . . Probe scanner

(51). . . Lifting mechanism

(6). . . Mobile device

(7). . . Thin film solar panel

First: a perspective view of a laser cutting device for a thin film solar cell of the present invention

Second figure: a schematic diagram of the moving state of the workbench of the present invention

Third: is a schematic diagram of the probe scanner of the present invention

Figure 4: Schematic diagram of the probe scanner of the present invention

Figure 5 is a flow chart of a laser cutting measurement method for a thin film solar cell of the present invention

(1). . . Pedestal

(2). . . Workbench

(3). . . Positioning guide column

(4). . . Laser head

(5). . . Probe scanner

(51). . . Lifting mechanism

(6). . . Mobile device

(7). . . Thin film solar panel

Claims (8)

A laser cutting device for a thin film solar cell, which is suitable for a large area thin film solar cell panel, the laser cutting device of the thin film solar cell comprises:
a pedestal, the upper end surface of the pedestal is provided with a groove, and a working table is arranged on the groove, and a positioning guide column is arranged on two sides of the upper end surface of the pedestal;
At least one laser head disposed on a front end surface of the positioning guide post for emitting a laser beam to a specific position on the thin film solar cell panel for cutting; and at least one probe scanner, The system is disposed on the front end surface of the positioning guide column and located on one side of the laser head, and is used as a depth profile measurement after the laser process. The laser cutting device for a thin film solar cell according to claim 1, wherein a moving device is disposed between the groove and the table. The laser cutting device for a thin film solar cell according to claim 1, wherein a linear motor and a propeller are disposed in the positioning guide post. The laser cutting device for a thin film solar cell according to claim 1, wherein the probe scanner further comprises a lifting mechanism. The laser cutting device for a thin film solar cell according to claim 4, wherein the lifting mechanism is a lifting motor. A laser cutting measurement method for a thin film solar cell, which is suitable for a laser cutting process of a large-area thin film solar cell panel, and the steps of the measuring method include:
In a first step, a probe scanner is lowered to the probe tip to contact a thin film solar cell panel surface by a lifting mechanism;
In the second step, the probe scanner is further assisted by a positioning guide column to move toward the laser cutting line; and in the third step, when the probe moves through the laser cutting line, the probe tip will follow The surface of the cutting line is recessed and lowered, and the curve of the depth and width of the laser cutting line can be obtained. The laser cutting measurement method for a thin film solar cell according to claim 6, wherein a linear motor and a propeller are disposed in the positioning guide column. The laser cutting measurement method for a thin film solar cell according to claim 6, wherein the lifting mechanism is a lifting motor.