CN107785286B - Laser packaging method - Google Patents

Abstract

The invention discloses a laser encapsulation method, which uses a laser to heat a glass frit pattern located between two substrates. The method includes: step 1: dividing the glass frit pattern into a path, dividing the glass frit pattern into several sub-segments, and there is an overlapping area between two adjacent sub-segments, and the overlapping area is called a splicing area; Step 2: Use a laser beam to repeatedly scan a sub-segment of the several sub-segments, and wait for After scanning, move to the starting point of the next subsection; Step 3: Repeat Step 2 until all frit patterns are scanned. By using the repeated scanning of the sub-sections, the invention not only provides quasi-synchronized uniform heating locally, so that the glass frit can reach the molten state in a short time, but also produces a scanning effect similar to the contour line on the macroscopic level. , the whole glass frit is softened and encapsulated successively, and a glass wall with controllable bonding ratio and better encapsulation quality is obtained.

Description

Laser packaging method

technical field

The invention relates to the field of laser packaging, in particular to a laser packaging method.

Background technique

Optoelectronic semiconductor devices have been widely used in various fields of life. Among them, OLED (Organic Light Emitting Diode) has become a research hotspot due to its good color ratio, wide viewing angle, high response speed and other characteristics, and has a good application prospect. However, the electrodes and organic layers in OLED displays are very sensitive to oxygen and moisture. Oxygen and moisture penetrating into the interior of the OLED device from the external environment can seriously shorten the lifespan of the OLED device. Therefore, it is very important to provide effective hermetic sealing for OLED devices.

In recent years, a sealing method using frit-assisted laser heating has been applied to the sealing of OLED displays. The glass frit described therein is doped with a material with high absorption rate for a specific light wavelength, and has the characteristic of low melting point. By heating and softening the frit with a high-energy laser, a hermetic seal is formed between the cover glass with the frit and the substrate glass with the OLED thereon. The frit is typically about 0.7-1 mm wide and 6-100 microns thick. The laser energy with controllable output from the laser irradiates the sealing line coated with the glass frit in sequence, so that the glass frit is heated and softened successively to form an airtight seal. However, this sequential method of heating the frit creates an uneven temperature distribution inside the frit. This uneven temperature distribution within the frit can lead to cracks, residual stress or delamination problems, preventing or weakening the hermetic connection between the cover glass and the substrate glass. At the same time, the main parameters of the sealing process, such as laser power, scanning speed, etc., need to be selected, which is restricted by this method and limits the improvement of the yield.

In the prior art, a quasi-synchronous scanning method is proposed for use in laser frit encapsulation, which has the advantages of wide process interval, high yield, and good uniformity of temperature distribution along the scanning direction. Then in practical applications, due to the constraints of the shape (circle) and uniformity (10%-20%) of the laser spot focused on the frit layer, as well as the size of the package pattern, the upper limit of the scanning speed and other factors , When scanning and encapsulating in the above-mentioned manner, the glass frit will form dense holes (bubbles) in its interior and near the edge, which will affect the encapsulation quality.

SUMMARY OF THE INVENTION

The invention provides a laser encapsulation method to solve the problem that the glass frit forms dense holes in the interior and near the edge.

In order to solve the above technical problems, the present invention provides a laser encapsulation method, which uses a laser to heat a frit pattern located between two substrates, so that the heated frit pattern seals the two substrates, and the method includes the steps of: 1: Perform path segmentation on the frit pattern, divide the frit pattern into several sub-segments, and there is an overlapping area between two adjacent sub-segments, and the overlapping area is called a splicing area; Step 2 Step 3: Repeat step 2 until all frit patterns are scanned.

Preferably, the shapes of the several sub-segments include straight lines, circular arcs and/or a combination of a plurality of straight lines and circular arcs.

Preferably, in step 1, the frit pattern is divided into several sub-segments with the same length and/or several sub-segments with different lengths.

Preferably, the length of the splicing region is less than half of the length of any one of the sub-segments.

Preferably, the step 2 includes: step 21: selecting a subsection as the initial scanning section, and calculating and updating the position coordinates of the starting point and the ending point of the initial scanning section; step 22: planning the process parameters for the subsection; Step 23: The laser beam moves from the start point of the subsection to the end point; Step 24: The laser beam jumps to the start point of the subsection, and step 23 is repeated until the number of jumps reaches the preset number of times and then step 25 is performed; Step 25: Calculate the position coordinates of the start point and end point of the next scan segment, and the laser beam jumps to the start point of the next scan segment; Step 26: Repeat steps 23-25 until all the frit patterns are scanned Finish.

Preferably, in the steps 24 and 25, the laser beam is in a no-output state during the jumping process.

Preferably, in the step 25, there is a time delay at the end point of the current subsection before the laser beam jumps and/or at the start point of the next subsection after the laser beam jumps.

Preferably, by controlling the scanning time, jumping time and delay time of the laser beam, each subsection has the same scanning period.

Preferably, when scanning the several subsections, if there is a special area, the output power and/or scanning speed of the laser beam is changed when scanning the special area, so as to change the energy obtained by the special area, wherein the The special area includes a circular arc segment in the frit pattern, a straight line segment connected with the circular arc segment, and an area through which electrodes pass.

Preferably, each sub-segment of the several sub-segments is further provided with a start area and/or a stop area, and the output power and/or scanning speed of the laser beam are changed when scanning the start area and/or the stop area, so as to change the The energy obtained in the start zone and/or stop zone.

Preferably, both the start region and the stop region are the splicing regions.

Preferably, it also includes step 4: using natural cooling, using a laser beam to scan the glass frit in a predetermined power curve manner, and/or using a laser beam to scan the glass frit in a temperature feedback manner, so as to cool the glass frit.

Compared with the prior art, the present invention divides an arbitrarily long frit pattern into several shorter sub-segments, and performs quasi-synchronous scanning on the sub-segments. Subsegments have good packaging quality. The invention effectively solves the problem of connection between the sub-sections by designing the splicing area between the sub-sections, so that the complete pattern can be finally obtained with excellent packaging quality and the process window is wider. Moreover, due to the fixed length of the sub-segment, the optimized process parameters can be applied to patterns of different sizes, which also lays a foundation for the pattern packaging process of large-size devices beyond the scanning field of view.

Description of drawings

Figure 1a is a schematic structural diagram of a laser scanning device in the present invention;

Figure 1b is a schematic structural diagram of a frit pattern in the present invention;

2 is a flowchart of a laser packaging method in Embodiment 1 of the present invention;

3 to 6 are schematic diagrams of scanning path planning of the sealed frit pattern in Embodiment 1 of the present invention;

7-8 are schematic diagrams of scanning path planning of the non-hermetic glass frit pattern in Embodiment 1 of the present invention;

Fig. 9 is the simulation comparison diagram of the temperature rise curve of the dynamic quasi-synchronous scanning method and the segmented quasi-synchronous scanning method in Embodiment 1 of the present invention;

10a-10d are power-position control curves in a single scan cycle in Embodiment 1 of the present invention;

11 is a schematic diagram of the segmented quasi-synchronous scanning path control of the sealed frit pattern in Embodiment 1 of the present invention;

12 is a top view of the top view of the glass frit after the encapsulation of a single sub-segment in Embodiment 1 of the present invention;

13 is a top view of the morphology of the glass frit after the encapsulation of adjacent sub-segments in Embodiment 1 of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the accompanying drawings of the present invention are all in a simplified form and use inaccurate scales, and are only used to facilitate and clearly assist the purpose of explaining the embodiments of the present invention.

Example 1

The present invention provides a laser packaging method, which adopts a laser scanning device as shown in FIG. 1a, the laser scanning device includes: a controller module 110, a laser scanning module 111, a laser module 112, and a temperature monitoring module 113, wherein the The controller module 100 is respectively connected with the laser scanning module 111 , the laser module 112 and the temperature monitoring module 113 for controlling the laser module 112 and the laser scanning module 111 and the scanning temperature, the laser module 112 and the laser scanning module 111 connected, the laser module 111 is used to generate laser light and send the laser light to the laser scanning module 111 with a predetermined power. The laser scanning module 111 is used to change the laser transmission direction and motion characteristics, and the temperature monitoring module 113 is used to Monitor the scanning temperature of the laser. Further, the laser scanning device further includes a computer 114 , and the computer 114 is connected to the controller module 110 for exchanging data with the controller module 110 .

This embodiment is used to form an airtight seal with glass frit for the OLED display 120, wherein the OLED display 120 is a typical glass package, and the main structure of the OLED display 120 includes a cover glass 121, a glass frit 122, and a substrate glass. 123 , OLED layer 125 and electrode 124 . The glass frit 122 is located on the substrate glass 123 of the OLED display 120, and its top view is shown in FIG. 1b. The glass frit 122 is pre-cured on the substrate glass 123 through screen printing and pre-sintering steps to form a rounded rectangular sealing line with a certain thickness. The OLED layer 125 on the substrate glass 123 is located on the inner side of the sealing line of the glass frit 122 , and there are electrodes 124 connected to the inside and outside of the OLED display 120 on the substrate glass 123 .

As shown in FIG. 2, the present invention provides a laser encapsulation method, which uses a laser to heat a pattern of frit 122 located between two base glasses 123, so that the heated pattern of frit 122 seals the two base glasses 123, It specifically includes:

Step 1: As shown in FIG. 3 to FIG. 8 , the pattern of the frit 122 to be scanned is divided into paths, and the pattern of the frit 122 is divided into several sub-segments 132, and there is an overlapping area between two adjacent sub-segments 132, This overlapping area is referred to as a tile 131 . Specifically, the subsection 132 may be a straight line or circular arc, or may be a combination of multiple straight lines or circular arcs. The length L ₁₃₂ of the sub-segments 132 refers to the cumulative length along the centerline direction of the pattern width of the frit 122 , including the sum of the lengths of the straight line segment and the circular arc segment. Usually, L ₁₃₂ <= 30mm.

Further, the sub-segment 132 has two end points, namely, the starting point 133 and the end point 134 respectively. Among them, 132(k) represents the k-th sub-segment 132, which is taken from 1 to N, where N is the total number of sub-segments 132 after division, and 133(k) and 134(k) represent the k-th sub-segment 132 The starting point and the end respectively point.

The splicing area 131 is an area between the end point 134(k) of the previous subsection 132(k) and the start point 133(k+1) of the next subsection 132(K+1), which has a certain Length L ₁₃₁ , where L ₁₃₁ <L ₁₃₂ /2. Further, L ₁₃₁ <= 2mm is generally taken.

It should be noted that the pattern of the frit 122 can be divided into several sub-segments 132 of equal length, as shown in FIGS. 3 , 5 and 7 ; of course, the pattern of the frit 122 can also be divided into several sub-segments of approximately the same length 132 and a sub-segment 132 with a slightly shorter or longer length, of course, the slightly shorter and longer here are relative to other sub-segments 132, as shown in FIG. 4 . Further, the pattern of the glass frit 122 can also be divided into several sub-segments 132 with approximately the same length and several sub-segments 132 with different lengths.

Of course, the pattern of the glass frit 122 in this embodiment may be a closed pattern, such as a rounded rectangle as shown in FIG. 3 and FIG. 4 , a circle as shown in FIG. 5 , and an oval as shown in FIG. 6 . It can also be a non-hermetic pattern, such as a straight pattern as shown in Figures 7 and 8.

Step 2: Use the laser beam to repeatedly scan the subsection 132 several times, and move to the starting point of the next subsection 132 after the scanning is completed. Specifically, this step 2 includes:

Step 21 : Select a subsection 132 as the initial scanning section, and calculate and update the position coordinates of the starting point 133 and the ending point 134 of the initial scanning section; usually, the laser beam will scan in the order of increasing serial numbers. However, for airtight patterns of any shape, the laser beam can start scanning from subsections 132 of any number, while for non-hermetic patterns, subsections 132 at one end of frit 122 are usually selected as initial scanning sections.

Step 22: Planning the process parameters for the sub-section 132; the process parameters specifically include the speed, power and trajectory of the current sub-section 132, and when the glass frit 122 has the same or similar printing and pre-sintering processes, the process implemented by it The parameters can be consistent, so that the known process parameters can be easily applied to encapsulate glass frits 122 of different sizes;

Step 23: the laser beam is moved from the start point 133 of the subsection 132 to the end point 134;

Step 24: the laser beam jumps to the starting point 133 of the subsection 132, and repeats step 23 until the number of jumps reaches a preset number of times and then performs step 25;

Step 25: Calculate the position coordinates of the start point 133 and the end point 134 of the next subsection 132, and the laser beam jumps to the start point 133 of the next subsection 132;

Step 26: Repeat steps 23-25 until all the frit patterns are scanned.

Specifically, the controller module 110 controls the laser scanning module 111 to project the laser beam to the starting point 133(k) of the current subsection 132, controls the laser to output the laser energy P at a higher power, and controls the laser beam to output the laser energy P at a higher power. The speed moves V _scan to scan the current subsection 132 , and the scanning direction is from the start point 133(k) to the end point 134(k). When the laser beam scans to the end point 134(k), the output of the laser energy is stopped and the laser beam is controlled to jump to the start point 133(k) at a higher speed V _jump . Preferably, there may be a certain time delay before and after the jump of the laser beam, that is, the laser beam remains at the start point 133(k) or the end point 134(k) for a certain time t _delay , and is in a state of no laser output. . The time period during which the laser is output is called the scanning phase, the time period during which the laser is not output is called the jumping phase, and the scanning phase plus the jumping phase is called a scanning period of sub-segment encapsulation.

A plurality of the single scanning cycles are repeated until the glass frit 122 is heated and softened and the connection of the required quality is completed. The glass frit 122 of the current sub-segment 132 can obtain enough energy to connect the two glass substrates to form a partial air-tight sealed connection by using multiple single scanning cycles of laser scanning; the sufficient energy can It appears that the temperature of the glass frit 122 reaches and exceeds its softening point (melting point). The laser scanning of the multiple scanning periods can be performed by using the same power curve for each scanning period, so that the glass frit 122 is heated with a temperature curve with a gradually decreasing temperature rise, and the target temperature can be reached by increasing the number of scans. . In the single scanning cycle, the glass frit 122 is heated sequentially after absorbing the laser energy, and the glass frit of each subsection 132 is heated multiple times. Since the length L ₁₃₂ of the subsection 132 is constrained to be within a small value (<=30mm), compared with the quasi-synchronized scheme adopted in the past, for the same scanning speed, power, scanning times and spot shape, the divided In the segment quasi-synchronization mode, the interval at which the fixed position on the current sub-segment 132 is heated by the beam irradiation is shorter, so it has a better temperature rise effect. The simulated temperature curve is shown in FIG. 9 .

Step 3: Repeat Step 2 until all the patterns of the frit 122 are scanned. Preferably, this step is to compare the current scan times with the predetermined total scan times to determine whether all scans are completed. No go back to step 2.

Further, the present invention can set a start area, a stop area, and other preset areas such as electrode coverage areas in a single subsection 132 according to actual needs (eg, when the laser power needs to be adjusted). The start area and the stop area in this embodiment may also be set in the splicing area 131 , that is, overlapping with the splicing area 131 . In the above-mentioned areas, the controller module 110 controls the laser module 112 and the laser scanning module 111 to synchronize the movement and scanning operation of the laser with the laser power adjustment operation, that is, the laser beam can linearly or non-linearly change the laser in the above-mentioned areas. Output power and/or laser scanning speed, so that other regions in the sub-section 132 other than the above-mentioned regions can obtain relatively uniform energy, and at the positions of the starting area, the stopping area and the preset area, different from the above-mentioned areas can be obtained. The relatively uniform energy in other regions can also obtain relatively non-uniform energy different from the above-mentioned other regions, and then scan the sub-segment 132 region through which electrodes or other devices pass.

As shown in Fig. 10a to Fig. 10d, Fig. 10a to Fig. 10b are the power-position control curves in which the start area, the stop area and the electrode coverage area are set at the same time in a single scan cycle respectively; Fig. 10c shows that only the stop area and the electrode are set The power-position control curve of the coverage area; Figure 10d shows the power-position control curve with only the starting area and the electrode coverage area set.

Further, the present invention further includes step 4: cooling the glass frit 122 . There are two cooling methods in the present invention. One is: after the glass frit 122 absorbs enough energy, the laser output is turned off to cool the glass frit 122 naturally. Since the glass frit 122 is heated approximately synchronously, its cooling rate is relatively sequential. More gentle; another cooling method is: still repeat the scanning cycle, scan the glass frit 122 with a lower laser power through a predetermined power curve method or a temperature feedback method, so that the glass frit 122 is cooled according to the predetermined cooling curve. The described cooling curve has a moderate cooling rate, so that the thermal stress generated during the cooling process can be better minimized. Of course, the method of controlling the cooling of the glass frit 122 may be to control the entire cooling process of the glass frit 122, or to control the part where the cooling rate of the glass frit 122 is relatively fast in a certain period of the natural cooling process, while the rest of the time is controlled. Some use natural cooling.

As shown in FIG. 11 , in order to carry out dynamic scanning path planning for the encapsulated glass frit 122 pattern, the encapsulated glass frit 122 pattern is divided into several sub-segments 132 of equal length, where the length of the sub-segments 132 is 29 mm, then 4 sub-sections 132, the length of the splicing area 131 is 1 mm;

Select subsection 132(1) to start packaging, and output 115-130W of laser beam power to scan from the starting point 133(1) to the ending point 134(1) at a constant speed of 4m/s. The power-position control curve is shown in Figure 10b. Then turn off the laser output, jump to the starting point 133 (1) at a speed of 8m/s; repeat 40 times, for the subsection covering the rounded corner pattern, use a power different from the linear area for the rounded corner area. Generally, The straight line area of 0.1mm before entering the fillet and 0.1mm leaving the fillet is included in the fillet area, and the laser power used is 105-110W;

then. Clockwise, subsection 132(2) is selected for packaging. The predetermined position of the laser spot is controlled to jump to the end point 133 (2), and the encapsulation is completed by referring to steps 2 to 3;

It should be noted that in this embodiment, a certain sub-section 132 is scanned by laser irradiation for multiple times, so that the temperature of the glass frit 122 on the current sub-section 132 is increased until sufficient energy is obtained to melt and soften the glass frit 122, and finally the glass frit 122 is melted and softened. The upper and lower glass substrates corresponding to the non-splicing area of the subsection 132 are connected together to form a locally uniform and dense glass wall. This process is called subsection encapsulation. The feature expansion description for the glass wall formed by sub-segment encapsulation is as follows:

1. After encapsulation, the non-splicing area of the subsection 132 forms an encapsulated area 201 with the same color and shape along the width direction of the glass frit, or is divided into an encapsulated area 201 and an unencapsulated area 203, wherein the upper and lower glass The dense and uniform packaged area 201 connected by the substrates occupies most of the area, and the width of the partial area is >85% of the total width of the frit 122 pattern, as shown in FIG. 12 .

2. After encapsulation, the splicing area of the sub-section 132 forms the encapsulated area 201 with the same color and shape along the width direction of the glass frit 122, or at least two parts with different colors or shapes. The two parts are respectively For splicing the packaged area 202 and the unpackaged area 203 .

Wherein, when the adjacent sub-segments 132 of the sub-segment 132 do not implement sub-segment encapsulation, the width of the spliced encapsulation area 202 on this side should be significantly smaller than the width of the encapsulated area 201; when the adjacent sub-segments of the sub-segment 132 are When sub-segment encapsulation has been implemented, the width of the splice encapsulation area 202 on this side should be the same as or close to the width of the encapsulated area 201 .

The other sub-segments 132 are sequentially encapsulated by the laser, so that the other sub-segments 132 are heated, melted and softened successively, and finally, the entire pattern of the glass frit 122 is encapsulated to form a complete, uniform and dense glass wall, so as to realize the gas Hermetic seal.

For a single scan cycle in the sub-segment encapsulation, the total time it consumes is called the single scan cycle time _tonescan , which can be approximately calculated by the following formula:

In this embodiment, the time t _onescan (k) of any single scan period of any subsection 132(k) is equal.

That is: for a single subsection 132(k), any single scan cycle time _tonescan (k) should be equal; for different subsections 132(k) and 132(j), its single scan cycle time _toonescan should be Satisfy:

t _onescan(k) ≈t _onescan(j)

Specifically, when the frit 122 pattern is divided into several sub-segments 132, the scanning speed V _scan is always a constant value, and the jumping speed V _jump is also a constant value. In order to obtain the shortest scanning cycle time, take If the delay time t _delay is 0, the time of a single scan cycle should be approximated by the following formula:

When the frit 122 pattern is divided into several sub-segments 132(1)-132(N-1) with approximately the same length and a sub-segment 132(N) with a slightly shorter length, for the sub-segments 132(1)-132 (N-1), still take t _delay as 0, the time of a single scan cycle is calculated by the following formula:

For subsection 132(N), the jump speed and delay time can be adjusted to ensure that the time of a single scan cycle is consistent. The jump speed and delay time of this subsection should satisfy:

When the frit 122 pattern is divided into several sub-segments 132 with different lengths, any two sub-segments 132(k) and 132(j) should satisfy:

Example 2

The difference between this embodiment and Embodiment 1 is that this embodiment uses a galvanometer as the laser scanning device. Due to the size constraints of the field of view of the galvanometer, the scanning field of view of the galvanometer needs to be determined during the laser scanning process. In practice, the steps are as follows:

Divide the encapsulated glass frit 122 pattern into several sub-segments 132 of equal length, and take the sub-segments 132 as 29 mm long to obtain N sub-segments 132, and the length of the splicing area 131 is 1 mm;

Move the galvanometer to the top of the subsection 132(1), so that the scanning field of view of the galvanometer covers the connected subsections 132 as much as possible;

Select subsection 132(1) to start packaging, and scan the laser beam output power of 115-130W at a constant speed of 4m/s from the start point 133(1) to the end point 134(1). The speed of 8m/s jumps to the starting point 133 (1); repeats 40 times, for the sub-section 132 covering the rounded corner pattern, the power of the rounded corner area is different from that of the straight area. The straight line area of 0.1mm and the rounded corner of 0.1mm is included in the rounded corner area, and the laser power used is 105-110W;

Within the scanning field of view of the galvanometer, in a clockwise direction, subsection 132(2) is selected for packaging.

By analogy, after completing the laser scanning encapsulation of all subsections 132 in the current galvanometer scanning field of view, move the galvanometer to the next position, which can cover as many subsections 132 as the most recently completed scanning encapsulation. For the adjacent subsections 132 to be scanned, the scanning packaging of all subsections 132 in the current scanning field of view is completed; and so on, the packaging of all subsections 132 is completed.

Obviously, those skilled in the art can make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (13)

1. A laser packaging method using a laser to heat a frit pattern located between two substrates such that the heated frit pattern seals the two substrates, the method comprising:

step 1: dividing the path of the frit pattern into a plurality of subsections, wherein a section of overlapped area is arranged between every two adjacent subsections, and the overlapped area is called as a splicing area;

the length of each sub-segment is less than or equal to 30mm;

step 2: using laser beam to repeatedly scan from the starting point to the end point of one subsection in the subsections for many times, and moving to the starting point of the next subsection after the scanning is finished;

and step 3: and (5) repeating the step (2) until all the frit patterns are scanned completely.

2. The laser packaging method of claim 1, wherein the shape of the plurality of sub-segments comprises a straight line and/or a circular arc.

3. The laser packaging method of claim 1, wherein in step 1, the frit pattern is divided into a plurality of sub-segments of the same length and/or a plurality of sub-segments of different lengths.

4. The laser packaging method of claim 1, wherein the length of the splicing region is less than half of the length of any of the plurality of sub-segments.

5. The laser packaging method of claim 1, wherein the step 2 comprises: step 21: selecting a sub-segment as an initial scanning segment, and calculating and updating position coordinates of a starting point and an ending point of the initial scanning segment;

step 22: planning the process parameters of the subsections; step 23: the laser beam moves from the starting point to the ending point of the subsection;

step 24: skipping the laser beam to the starting point of the subsection, and repeatedly executing the step 23 until the skipping times reach the preset times and then executing the step 25;

step 25: calculating the position coordinates of the starting point and the ending point of the next subsegment, and jumping the laser beam to the starting point of the next subsegment;

step 26: repeating steps 23-25 until the frit pattern is completely scanned.

6. The laser packaging method of claim 5, wherein in steps 24 and 25, the laser beam is in a no-output state during jumping.

7. The laser packaging method of claim 5, wherein in step 25, there is a time delay before the laser beam jumps at the end point of the current sub-segment and/or after the laser beam jumps at the start point of the next sub-segment.

8. The laser packaging method of claim 7, wherein each of the sub-segments has the same scanning period by controlling a scanning time, a jump time, and a delay time of the laser beam.

9. The laser packaging method of claim 1, wherein when scanning the plurality of sub-segments, if a special region exists, the output power and/or scanning speed of the laser beam is changed when scanning the special region to change the energy obtained by the special region, wherein the special region comprises a circular arc segment in the frit pattern, a straight line segment connected with the circular arc segment, and a region through which an electrode passes.

10. The laser packaging method of claim 1, wherein each of the plurality of sub-segments is further provided with a start area and/or a stop area, and the output power and/or the scanning speed of the laser beam is changed when the start area and/or the stop area is scanned to change the energy obtained by the start area and/or the stop area.

11. The laser packaging method of claim 10, wherein the start zone and the stop zone are both the splicing zones.

12. The laser packaging method of claim 1, further comprising step 4: the frit is cooled by natural cooling, by scanning the frit with a laser beam in a predetermined power curve and/or by scanning the frit with a laser beam in a temperature feedback manner.

13. The laser packaging method of claim 1, wherein the shape of the plurality of sub-segments comprises a combination of straight lines and circular arcs.

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