Laser annealing method and device

Abstract

The invention provides a laser annealing method which comprises the following steps: a substrate is arranged on a motion table, first laser and second laser are projected onto the substrate, and light spots of the first laser and the second laser projected onto the substrate have an overlapping region in a scanning direction so as to anneal the substrate, and measuring the temperature of the substrate at the irradiation part of the first laser and / or the second laser, and adjusting the energy of the first laser and / or the second laser according to the measured temperature. According to the invention, closed-loop control is carried out on the energy of the first laser and / or the second laser by measuring the temperature, so that the annealing uniformity of the whole substrate is ensured. Correspondingly, the invention further provides laser annealing equipment.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a laser annealing method and apparatus. Background Art

[0002] Laser annealing refers to a processing method of annealing a workpiece using a laser. Since laser annealing has controllability in the annealing region and can reach the set temperature in a short time, it is widely used in semiconductor processes.

[0003] In the manufacturing process of power devices such as insulated gate bipolar transistors (IGBTs), it is necessary to anneal and activate boron (B) and phosphorus (P) implanted in the P collector region (a relatively shallow region from the device surface) and the buffer layer (a relatively deep region from the device surface), and at the same time, it is necessary to prevent the metal (such as aluminum) on the front of the device from melting due to heat.

[0004] In order for laser annealing to penetrate into the deep layer of the material, make the material heated evenly, improve the absorption coefficient of the material, reduce the temperature difference between the upper and lower surfaces of the material, and improve the structural morphology and crystallization properties after recrystallization, a laser annealing scheme that usually uses pulsed laser and continuous laser in combination is adopted. However, since the laser that emits pulsed laser has an overshoot characteristic in the gate control mode, the power of the pulsed laser is likely to fluctuate, resulting in fluctuations in the annealing temperature on the substrate and reducing the annealing uniformity. Summary of the Invention

[0005] The purpose of the present invention is to provide a laser annealing method and apparatus for solving the problem of low uniformity of existing laser annealing.

[0006] To achieve the above purpose, the present invention provides a laser annealing method, including:

[0007] Placing a substrate on a moving stage, the moving stage being used to drive the substrate to move;

[0008] Projecting a first laser and a second laser onto the substrate to anneal the substrate, the light spots of the first laser and the second laser projected onto the substrate having an overlapping region in the scanning direction;

[0009] Measuring the temperature of the substrate at the irradiation position of the first laser and / or the second laser; and,

[0010] Adjusting the energy of the first laser and / or the second laser according to the measured temperature.

[0011] Optionally, the first laser is a pulsed laser and the second laser is a continuous laser.

[0012] Optionally, measure the temperature of the substrate at the irradiation sites of the first laser and the second laser, and adjust the energy of the first laser and / or the second laser according to the measured temperature; and / or, measure the temperature of the substrate at the irradiation site of the second laser, and adjust the energy of the first laser according to the measured temperature.

[0013] Optionally, the step of adjusting the energy of the first laser and / or the second laser according to the measured temperature includes:

[0014] Obtain the temperature deviation between the measured temperature and an ideal temperature;

[0015] Obtain the power deviation of the first laser and / or the second laser according to the temperature deviation; and,

[0016] Adjust the energy of the first laser and / or the second laser according to the rate deviation.

[0017] Optionally, the step of obtaining the power deviation of the first laser and the second laser according to the temperature deviation includes:

[0018] Obtain the energy proportion coefficient of the first laser and the second laser during annealing;

[0019] Allocate the temperature deviation to the first laser and the second laser according to the energy proportion coefficient; and,

[0020] Obtain the corresponding power deviation according to the temperature deviation allocated to each of the first laser and the second laser.

[0021] Optionally, adjust the energy of the first laser by adjusting the frequency or power of the first laser; and / or, adjust the energy of the second laser by adjusting the power of the second laser.

[0022] Optionally, the light spot of the second laser reaches the substrate before the light spot of the first laser.

[0023] Optionally, before annealing the substrate, the substrate is outside the working ranges of the first laser and the second laser, and the first laser and the second laser are turned on in advance.

[0024] Optionally, after the energies of the first laser and the second laser are stable, move the substrate into the working ranges of the first laser and the second laser, and perform annealing.

[0025] Optionally, the second laser is turned on before the first laser.

[0026] Optionally, during annealing, when the substrate moves outside the working ranges of the first laser and the second laser after each field of view of the substrate is scanned, the energy of the second laser is reduced, and before scanning the next field of view of the substrate, the energy of the second laser is increased.

[0027] Optionally, after the energy of the second laser is stabilized, the substrate is moved to the working ranges of the first laser and the second laser, and the next field of view of the substrate is scanned.

[0028] The present invention also provides a laser annealing device, comprising:

[0029] A moving stage for carrying a substrate and driving the substrate to move;

[0030] A first laser generating unit for emitting a first laser;

[0031] A second laser generating unit for emitting a second laser;

[0032] A projection unit for projecting the first laser and the second laser onto the substrate to anneal the substrate, wherein the light spots of the first laser and the second laser projected onto the substrate have an overlapping area in the scanning direction;

[0033] A temperature measuring unit for measuring the temperature of the substrate at the irradiation position of the first laser and / or the second laser; and,

[0034] A control unit for adjusting the energy of the first laser and / or the second laser according to the measured temperature.

[0035] In the laser annealing method provided by the present invention, a substrate is placed on a moving stage, the first laser and the second laser are projected onto the substrate, and the light spots of the first laser and the second laser projected onto the substrate have an overlapping area in the scanning direction to anneal the substrate. The temperature of the substrate at the irradiation position of the first laser and / or the second laser is measured, and the energy of the first laser and / or the second laser is adjusted according to the measured temperature. The present invention performs closed-loop control on the energy of the first laser and / or the second laser by measuring the temperature, ensuring the annealing uniformity of the entire substrate. Correspondingly, the present invention also provides a laser annealing device. Description of the Drawings

[0036] Figure 1 It is a schematic structural diagram of the laser annealing device provided by an embodiment of the present invention;

[0037] Figure 2 It is a flowchart of the laser annealing method provided by an embodiment of the present invention;

[0038] Figure 3 Schematic diagram of energy control of the first laser and the second laser provided by an embodiment of the present invention;

[0039] Figure 4 Schematic diagram of temperature closed-loop control provided by an embodiment of the present invention;

[0040] Figure 5 Graph showing the relationship between time and temperature per unit area of the substrate during annealing under ideal conditions provided by an embodiment of the present invention;

[0041] Wherein, the reference numerals are:

[0042] 101 - First laser generating unit; 102 - Second laser generating unit; 201 - First optical unit; 202 - Second optical unit; 301 - First optical path turning unit; 302 - Second optical path turning unit; 400 - Projection unit; 500 - Control unit; 600 - Substrate; 700 - Moving stage; 800 - Temperature detection unit; L1 - First laser; L2 - Second laser; Tem - Measured temperature; Tset - Ideal temperature; ΔT - Temperature deviation; Ctrl1 - First control signal; Ctrl2 - Second control signal. Detailed implementation manners

[0043] The following will describe the detailed implementation manners of the present invention in more detail with reference to the schematic diagrams. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in very simplified forms and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0044] Figure 1 Schematic diagram of the structure of the laser annealing device provided for this embodiment. As Figure 1 shown, the laser annealing device includes a first laser generating unit 101, a second laser generating unit 102, a moving stage 700, a control unit 500, and a temperature detection unit 800.

[0045] The moving stage 700 is used to carry the substrate 600 and can also drive the substrate 600 to move so that during annealing, the laser can scan the surface of the substrate 600. Preferably, the workpiece stage 109 has multiple degrees of freedom of movement and can achieve high-precision movement of the workpiece, which helps to improve the annealing quality of the workpiece.

[0046] The first laser generating unit 101 and the second laser generating unit 102 are respectively configured to provide a first laser L1 and a second laser L2. In this embodiment, the first laser L1 is a pulsed laser, and the second laser L2 is a continuous laser. The second laser L2 can be used to preheat the substrate 600, and the first laser L1 and the second laser L2 cooperate with each other to anneal the substrate 600.

[0047] In this embodiment, the first laser generating unit 101 may include a single solid-state laser or at least two integrated solid-state lasers. The solid-state laser may be a second harmonic solid-state laser; the second laser generating unit 102 may include a semiconductor laser, such as a semiconductor laser in the infrared to near-infrared band. The wavelength range of the first laser L1 output by the first laser generating unit 101 may be 510 nm to 540 nm. The wavelength range of the second laser L2 output by the second laser generating unit 102 may be 650 nm to 1000 nm.

[0048] The laser annealing device further includes a first optical unit 201, a second optical unit 202, a first optical path turning unit 301, a second optical path turning unit 302, and a projection unit 400. The first optical unit 201 and the first optical path turning unit 301 are sequentially arranged on the optical path of the first laser L1. The first optical unit 201 can perform operations such as collimating, beam expanding, or shaping on the first laser L1. The first optical path turning unit 301 can turn the optical path of the first laser L1, thereby saving lateral space; the second optical unit 202 and the second optical path turning unit 302 are sequentially arranged on the optical path of the second laser L2. The second optical unit 202 can perform operations such as collimating, beam expanding, or shaping on the second laser L2. The second optical path turning unit 302 can turn the optical path of the second laser L2, thereby saving lateral space. The projection unit 400 is configured to focus and project the first laser L1 and the second laser L2 onto the substrate 600 to form a light spot.

[0049] Further, the light spots of the first laser L1 and the second laser L2 projected on the substrate 600 have an overlapping area in the scanning direction. For example, the projection unit 400 can project the first laser L1 and the second laser L2 to the same position on the substrate 600, so that the first laser L1 and the second laser L2 can cooperate and jointly anneal the substrate 600.

[0050] In this embodiment, the temperature detection unit 800 is a non-contact temperature detector, which can measure the temperature of the substrate at the overlapping portion of the first laser L1 and the second laser L2. That is, the temperature detection unit 800 can measure the temperature of the substrate 600 at the irradiation position of the first laser L1 and / or the second laser L2. That is, the temperature measurement can be the temperature measurement during the irradiation of the first laser L1 or the second laser L2 in terms of time, or the temperature measurement during the simultaneous irradiation of the first laser L1 and the second laser L2.

[0051] Please continue to refer to Figure 1 , the control unit 500 is connected to the temperature detection unit 800, the first laser generation unit 101, and the second laser generation unit 102, and can adjust the energy of the first laser L1 and / or the second laser L2 according to the measured temperature of the temperature detection unit 800. For example, the control unit 500 can output a first control signal Ctrl1 with a set frequency to the first laser generation unit 101, and the first control signal Ctrl1 controls the first laser generation unit 101 to output the first laser L1 at the set frequency and power; the control unit 500 can also output a second control signal Ctrl2 with a set power to the second laser generation unit 102, and the second control signal Ctrl2 controls the second laser generation unit 102 to output the second laser L2 at the set power.

[0052] Furthermore, the control unit 500 is also connected to the stage 700, and the control unit 500 can control the movement of the workpiece stage 700.

[0053] Based on this, this embodiment also provides a laser annealing method. Figure 2 is a flowchart of the laser annealing method provided in this embodiment. As Figure 2 shown, the laser annealing method includes:

[0054] Step S100: Place a substrate on the stage, and the stage is used to drive the movement of the substrate;

[0055] Step S200: Project a first laser and a second laser onto the substrate to anneal the substrate, and the light spots of the first laser and the second laser projected on the substrate have an overlapping area in the scanning direction;

[0056] Step S300: Measure the temperature of the substrate at the irradiation position of the first laser and / or the second laser; and,

[0057] Step S400: Adjust the energy of the first laser and / or the second laser according to the measured temperature.

[0058] Figure 3 Schematic diagram of energy control for the first laser and the second laser provided in this embodiment. In combination with Figure 1 and Figure 3 as shown, step S100 is executed to place the substrate 600 on the moving stage 700. The moving stage performs alignment, leveling and other preparation operations on the substrate 600. After that, the moving stage 700 moves to the zero position. When the moving stage 700 is at the zero position, the substrate 600 is outside the working ranges of the first laser L1 and the second laser L2 (the first laser L1 and the second laser L2 are not projected onto the substrate 600 but onto the moving stage 700).

[0059] Next, the moving stage 700 drives the substrate 600 to start moving to slowly move the substrate 600 into the working ranges of the first laser L1 and the second laser L2. When the moving stage 700 moves to point A, the substrate 600 is still outside the working ranges of the first laser L1 and the second laser L2. At this time, the control unit 500 can control the second laser generating unit 102 to turn on and emit the second laser L2. The power output by the second laser generating unit 102 is not stable when it is just turned on, so the energy of the second laser L2 is also unstable. However, starting from point A, the power output by the second laser generating unit 102 gradually increases from 0.

[0060] When the moving stage 700 moves to point B, the substrate 600 is still outside the working ranges of the first laser L1 and the second laser L2. At this time, the control unit 500 can control the first laser generating unit 101 to turn on and emit the first laser L1. The power output by the first laser generating unit 101 is not stable when it is just turned on, so the energy of the first laser L1 is also unstable. However, starting from point B, the power output by the first laser generating unit 101 gradually increases from 0.

[0061] When the moving stage 700 moves to point C, the powers output by the second laser generating unit 102 and the first laser generating unit 101 have both approached the corresponding target scanning powers (P_scan1 and P_scan2). It can be considered that the powers output by the second laser generating unit 102 and the first laser generating unit 101 have become stable, so the energies of the second laser L2 and the first laser L1 have also become stable. At this time, the moving stage 700 can continue to move to move the substrate 600 into the working ranges of the first laser L1 and the second laser L2 to start annealing the substrate 600.

[0062] In this way, when annealing the substrate 600, the energies of the first laser L1 and the second laser L2 are both stable. Therefore, the annealing uniformity at the edge of the substrate 600 can be improved.

[0063] It should be understood that due to the different characteristics of the first laser generating unit 101 and the second laser generating unit 102, the time required for them to output stable scanning power from relatively low power is also different. Generally speaking, the stabilization time of the second laser generating unit 102 is longer than that of the first laser generating unit 101. Therefore, in this embodiment, before formal annealing, the second laser generating unit 102 is turned on first and then the first laser generating unit 101 is turned on, so that the second laser generating unit 102 has more stabilization time without wasting the energy of the first laser generating unit 101. Moreover, before the first laser L1 and the second laser L2 are stabilized, the first laser L1 and the second laser L2 are not irradiated on the substrate 600 and will not cause adverse effects on the substrate 600.

[0064] In some embodiments, the second laser generating unit 102 and the first laser generating unit 101 can also be turned on simultaneously, or the first laser generating unit 101 can also be turned on before the second laser generating unit 102.

[0065] Furthermore, in this embodiment, the moments when the energies of the first laser L1 and the second laser L2 reach the stable state are the same, that is, the energies of the first laser L1 and the second laser L2 both reach the stable state at point C. However, this should not be taken as a limitation. The moments when the energies of the first laser L1 and the second laser L2 reach the stable state can also be different, as long as they reach the stable state before the substrate 600 moves into the working ranges of the first laser L1 and the second laser L2.

[0066] Figure 3 In, point C is exactly the edge of the substrate 600, that is, the annealing starting point. However, this should not be taken as a limitation. Point C can also be located between 0 mm and 2 mm in front of the annealing starting point.

[0067] Figure 4 is a schematic diagram of the temperature closed-loop control provided in this embodiment. Combining Figure 1 and Figure 4 As shown, steps S200 and S300 are executed to project the first laser L1 and the second laser L2 onto the substrate 600 to anneal the substrate 600. Figure 5 is a graph showing the relationship between time and temperature in the unit area region of the substrate 600 during annealing in the ideal case provided in this embodiment. As Figure 5As shown, during annealing, the moving stage 700 drives the substrate 600 to move in the scanning direction (the horizontal direction in this embodiment), and the spots of the second laser L2 and the first laser L1 also move in the scanning direction, thereby annealing each unit area region of the substrate 600 one by one.

[0068] It should be understood that the spot of the second laser L2 can reach the substrate 600 before the spot of the first laser L1, thereby preheating the substrate 600 and pre-raising the temperature of the substrate 600 (for example, raising it to 600 °C). Subsequently, the spot of the first laser L1 reaches the position that has been preheated by the spot of the second laser L2, raising the temperature at that place to the annealing temperature (for example, 1200 °C), thereby completing the annealing at that place.

[0069] During annealing, the temperature measurement unit 800 measures the temperature of the substrate 600 at the irradiation position of the first laser L1 and / or the second laser L2 and feeds it back to the control unit 500.

[0070] Next, step S400 is executed. The control unit 500 adjusts the energy of the first laser L1 and / or the second laser L2 according to the measured temperature Tem, and performs closed-loop control on the energy of the first laser L1 and / or the second laser L2 through the measured temperature Tem, ensuring the annealing uniformity of the entire substrate 600.

[0071] Specifically, the control unit 500 can adjust only the energy of the first laser L1 or the second laser L2 according to the measured temperature Tem, or can adjust the energy of both the first laser L1 and the second laser L2 simultaneously according to the measured temperature Tem.

[0072] It should be noted that when measuring the temperature of the substrate 600 at the irradiation positions of the first laser L1 and the second laser L2, the energy of the first laser L1 and / or the second laser L2 can be adjusted according to the measured temperature Tem. For example, when the annealing temperature measured by the temperature measurement unit 800 during the irradiation of the first laser L1 and the second laser L2 is too low (e.g., lower than 1200 °C), the measured temperature Tem can be fed back to the control unit 500, and the control unit 500 controls to increase the energy of the first laser L1 and / or the second laser L2 to meet the requirement of the final annealing temperature (e.g., 1200 °C). When measuring the temperature of the substrate 600 at the irradiation position of the second laser L2, the energy of the first laser L1 can be adjusted according to the measured temperature Tem. For example, when the preheating temperature measured by the temperature measurement unit 800 during the irradiation of the second laser L2 is too low (e.g., lower than 550 °C), the measured temperature Tem can be fed back to the control unit 500, and the control unit 500 controls to increase the energy of the first laser L1 to meet the requirement of the final annealing temperature (e.g., 1200 °C).

[0073] For example, when the control unit 500 only adjusts the energy of the first laser L1 according to the measured temperature, the temperature deviation ΔT between the measured temperature Tem and an ideal temperature Tset can be calculated first (ΔT is the absolute value of Tem - Tset), then the power deviation of the first laser L1 can be calculated according to the temperature deviation ΔT, and then the frequency or power of the first laser L1 can be adjusted according to the power deviation of the first laser L1 (specifically, the current magnitude of the first laser generating unit 101 can be adjusted), so as to adjust the energy of the first laser L1.

[0074] The control unit 500 can also adopt a similar method to adjust the energy of the second laser L2 according to the measured temperature. The difference is only that the control unit 500 can adjust the power of the second laser L2 according to the power deviation of the second laser L2 (specifically, the voltage magnitude of the second laser generating unit 102 can be adjusted), so as to adjust the energy of the first laser L1.

[0075] When the control unit 500 adjusts the energies of the first laser L1 and the second laser L2 according to the measured temperature, the temperature deviation ΔT (the absolute value of Tem - Tset) between the measured temperature Tem and an ideal temperature Tset can be calculated first, and then the energy ratio coefficient of the first laser L1 and the second laser L2 during annealing can be obtained; thereafter, the temperature deviation ΔT is distributed to the first laser L1 and the second laser L2 according to the energy ratio coefficient, and then the corresponding power deviations are obtained according to the temperature deviations respectively allocated to the first laser L1 and the second laser L2. Thereafter, the control unit 500 can adjust the energies according to the respective power deviations of the first laser L1 and the second laser L2.

[0076] It should be understood that the ideal temperature Tset is related to the measurement time of the measured temperature Tem. For example, if the measured temperature Tem is the temperature of the substrate 600 at the irradiation positions of the first laser L1 and the second laser L2, then the ideal temperature Tset is the ideal annealing temperature; if the measured temperature Tem is the temperature of the substrate 600 at the irradiation position of the second laser L2, then the ideal temperature Tset is the ideal preheating temperature. However, regardless of when the measured temperature Tem is measured, the ideal temperature Tset is an empirical value and can be obtained through actual tests.

[0077] For example, if the energy ratio coefficient of the first laser L1 and the second laser L2 is α1 / α2 = 2:1 and ΔT = 15 °C, then the temperature deviations respectively allocated to the first laser L1 and the second laser L2 are 10 °C and 5 °C. Calculate the power deviation of the first laser L1 under the temperature deviation of 10 °C and the power deviation of the second laser L2 under the temperature deviation of 5 °C, and then adjust the energy of the first laser L1 according to the power deviation of the first laser L1 and adjust the energy of the second laser L2 according to the power deviation of the second laser L2.

[0078] Please continue to refer to Figure 3 In this embodiment, the substrate 600 is annealed row by row. Each time the first laser L1 and the second laser L2 scan one row, annealing of one field of view of the substrate 600 can be completed. Then the first laser L1 and the second laser L2 scan the next row to complete annealing of the next field of view of the substrate 600 until the entire substrate 600 is annealed.

[0079] It should be understood that after the first laser L1 and the second laser L2 scan one field of view of the substrate 600, the substrate 600 will move outside the working ranges of the first laser L1 and the second laser L2 (providing a displacement margin for the next movement). At this time, the control unit 500 can reduce the energy of the second laser L2 (the power changes from P_scan to P_travel), avoid damage to the worktable 700 by the second laser L2 (at this time, the second laser L2 and the first laser L1 usually irradiate on the worktable 700), and also save energy.

[0080] Next, before the moving stage 700 moves the substrate 600 into the working ranges of the first laser L1 and the second laser L2, that is, before the first laser L1 and the second laser L2 scan the next field of view of the substrate 600, the energy of the second laser L2 is increased again (the power changes from P_travel to P_scan). And after the energy of the second laser L2 stabilizes, the substrate 600 is moved into the working ranges of the first laser L1 and the second laser L2, and the next field of view of the substrate 600 is scanned, so as to avoid uneven annealing at the edge of the substrate 600.

[0081] In summary, in the laser annealing method provided by the embodiments of the present invention, a substrate is disposed on a moving stage, a first laser and a second laser are projected onto the substrate, and the light spots projected by the first laser and the second laser on the substrate have an overlapping area in the scanning direction to anneal the substrate. The temperature at the irradiation position of the first laser and / or the second laser on the substrate is measured, and the energy of the first laser and / or the second laser is adjusted according to the measured temperature. The present invention performs closed-loop control on the energy of the first laser and / or the second laser by measuring the temperature, ensuring the annealing uniformity of the entire substrate. Correspondingly, the present invention also provides a laser annealing device.

[0082] It should be noted that the embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0083] It should also be noted that although the present invention has been disclosed above in preferred embodiments, the above embodiments are not intended to limit the present invention. For any person skilled in the art, without departing from the scope of the technical solution of the present invention, many possible changes and modifications can be made to the technical solution of the present invention by using the technical content disclosed above, or it can be modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of protection of the technical solution of the present invention.

[0084] It should also be understood that unless otherwise specified or indicated, the terms "first", "second", "third", etc. in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, rather than to represent the logical relationship or sequential relationship, etc. between the various components, elements, steps.

[0085] In addition, it should also be recognized that the terms described herein are only used to describe specific embodiments and are not used to limit the scope of the present invention. It must be noted that the singular forms "a" and "an" used herein and in the appended claims include plural references unless the context clearly dictates otherwise. For example, a reference to "a step" or "a device" means a reference to one or more steps or devices and may include sub-steps as well as sub-devices. All conjunctions used should be understood in their broadest sense. Also, the word "or" should be understood to have the definition of logical "or" rather than the definition of logical "exclusive or" unless the context clearly dictates otherwise. In addition, the implementation of the methods and / or devices in the embodiments of the present invention may include performing the selected tasks manually, automatically, or in combination.

Claims

1. A laser annealing method, characterized in that, Comprising: A substrate is disposed on a moving stage, and the moving stage is used to drive the substrate to move; A first laser and a second laser are projected onto the substrate to anneal the substrate, and the light spots of the first laser and the second laser projected on the substrate have an overlapping area in the scanning direction; Measuring the temperature of the substrate at the irradiation position of the first laser and / or the second laser; and Adjusting the energy of the first laser and / or the second laser according to the measured temperature.

2. The laser annealing method according to claim 1, wherein The first laser is a pulsed laser, and the second laser is a continuous laser.

3. The laser annealing method according to claim 2, characterized in that Measuring the temperature of the substrate at the irradiation positions of the first laser and the second laser, and adjusting the energy of the first laser and / or the second laser according to the measured temperature; and / or, measuring the temperature of the substrate at the irradiation position of the second laser, and adjusting the energy of the first laser according to the measured temperature.

4. The laser annealing method according to any one of claims 1 to 3, characterized in that, The step of adjusting the energy of the first laser and / or the second laser according to the measured temperature includes: Obtaining the temperature deviation between the measured temperature and an ideal temperature; Obtaining the power deviation of the first laser and / or the second laser according to the temperature deviation; and Adjusting the energy of the first laser and / or the second laser according to the power deviation.

5. The laser annealing method according to claim 4, wherein The step of obtaining the power deviation of the first laser and the second laser according to the temperature deviation includes: Obtaining the energy ratio coefficient of the first laser and the second laser during annealing; Allocating the temperature deviation to the first laser and the second laser according to the energy ratio coefficient; and Obtaining the corresponding power deviation according to the temperature deviation allocated to the first laser and the second laser respectively.

6. The laser annealing method according to claim 4, wherein Adjusting the energy of the first laser by adjusting the frequency or power of the first laser; and / or, adjusting the energy of the second laser by adjusting the power of the second laser.

7. The laser annealing method according to claim 2, characterized in that, The light spot of the second laser reaches the substrate before the light spot of the first laser.

8. The laser annealing method according to claim 1, characterized in that, Before annealing the substrate, the substrate is outside the working ranges of the first laser and the second laser, and the first laser and the second laser are turned on in advance.

9. The laser annealing method according to claim 8, wherein When the energies of the first laser and the second laser are stable, the substrate is moved into the working ranges of the first laser and the second laser for annealing.

10. The laser annealing method according to claim 8 or 9, characterized in that, The second laser is turned on before the first laser.

11. The laser annealing method according to claim 8 or 9, characterized in that, During annealing, when scanning one field of view of the substrate, when the substrate is moved outside the working ranges of the first laser and the second laser, the energy of the second laser is reduced, and before scanning the next field of view of the substrate, the energy of the second laser is increased.

12. The laser annealing method according to claim 11, wherein When the energy of the second laser is stable, the substrate is moved into the working ranges of the first laser and the second laser to scan the next field of view of the substrate.

13. A laser annealing device, characterized in that, Comprising: A moving stage for carrying a substrate and for driving the substrate to move; A first laser generating unit for emitting a first laser; A second laser generating unit for emitting a second laser; A projection unit for projecting the first laser and the second laser onto the substrate to anneal the substrate, wherein the spots of the first laser and the second laser projected onto the substrate have an overlapping area in the scanning direction; A temperature measurement unit for measuring the temperature of the substrate at the irradiation position of the first laser and / or the second laser; And, A control unit for adjusting the energy of the first laser and / or the second laser according to the measured temperature.

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