Laser annealing apparatus and laser annealing method

Abstract

This invention provides a laser annealing apparatus and a laser annealing method. The laser annealing apparatus includes a galvanometer module, a focusing module, and a beam homogenization and shaping module. The galvanometer module includes a galvanometer; the laser beam incident on the galvanometer module has its exit position changed by the rotation of the galvanometer. The focusing module focuses the laser beam exiting from the galvanometer module. The beam homogenization and shaping module has at least one degree of freedom; by changing the position of the beam homogenization and shaping module in this degree of freedom, the image quality of the laser spot can be adjusted. By adjusting the position of the beam homogenization and shaping module in this degree of freedom, the image quality of the laser spot can be easily adjusted, thereby improving the phenomenon of laser spot deformation and image quality deterioration caused by changes in the galvanometer scanning angle. The laser annealing method improves the laser annealing effect by adjusting the image quality of the laser spot at each field of view.

Description

Technical Field

[0001] This invention relates to the field of laser annealing, and particularly to a laser annealing apparatus and a laser annealing method. Background Technology

[0002] Laser annealing is a processing method that uses lasers to anneal workpieces. Compared to traditional baking annealing, laser annealing offers greater control over the annealing range and can reach the set temperature in a shorter time. It is now widely used in various annealing applications, and workpieces subjected to laser annealing can be made of substrates such as silicon, glass, ceramics, and metals.

[0003] A commonly used laser annealing device includes a light source module and a galvanometer module. The laser beam emitted by the light source module illuminates the galvanometer module and is reflected by two galvanometers within the galvanometer module. The light beam then passes through a focusing lens (such as a flat-field focusing lens) used in conjunction with the galvanometer module and illuminates the workpiece surface to form a light spot. The galvanometers within the galvanometer module rotate along corresponding axes driven by a motor, causing the light spot to move within the annealing range of the workpiece surface (i.e., galvanometer scanning), thereby changing the position of the light spot to achieve the purpose of annealing the workpiece surface.

[0004] However, research has found that during the annealing process, the aforementioned laser annealing apparatus suffers from unstable spot image quality at different positions within the field of view due to variations in the galvanometer scanning angle. Particularly, the spot formed at the edge of the field of view is prone to tilting and deformation due to differences in the galvanometer scanning angle, resulting in image quality that fails to meet process requirements. Furthermore, research has also revealed that distortion of the focusing lens in the aforementioned laser annealing apparatus can easily lead to spot deformation and poor image quality on the workpiece surface, affecting the laser annealing effect. Summary of the Invention

[0005] This invention provides a laser annealing apparatus to improve the spot deformation and image quality degradation caused by changes in the galvanometer scanning angle, thereby enhancing laser annealing efficiency and annealing effect. This invention also provides a laser annealing method.

[0006] On one hand, the present invention provides a laser annealing apparatus, the laser annealing apparatus comprising:

[0007] A galvanometer module includes a galvanometer, and the laser beam incident on the galvanometer module changes its exit position by rotating the galvanometer.

[0008] A focusing module is used to focus the laser beam emitted from the galvanometer module to form a light spot on the focal plane;

[0009] The light-uniform shaping module has at least one degree of freedom, and the image quality of the light spot can be adjusted by changing the position of the light-uniform shaping module in the degree of freedom.

[0010] Optionally, the uniform beam shaping module has a first degree of freedom to translate along a first direction and / or a second degree of freedom to translate along a second direction perpendicular to the first direction, wherein the plane formed by the first direction and the second direction is perpendicular to the direction of the laser beam incident on the uniform beam shaping module.

[0011] Optionally, the uniform light shaping module has a third degree of freedom of rotation about the first direction and / or a fourth degree of freedom of rotation about a second direction perpendicular to the first direction, wherein the plane formed by the first direction and the second direction is perpendicular to the direction of the laser beam incident on the uniform light shaping module.

[0012] Optionally, the homogenizing and shaping module includes a diffraction optical unit and an adjustment unit, wherein the adjustment unit is used to adjust the position of the diffraction optical unit in each degree of freedom.

[0013] Optionally, the homogenizing and shaping module further includes a mirror mount, on which the diffractive optical unit is disposed and moves with the mirror mount. The adjustment unit includes multiple adjustment components connected to the mirror mount, and each adjustment component adjusts the position of the diffractive optical unit in one degree of freedom by adjusting the position of the mirror mount.

[0014] Optionally, the adjustment assembly includes an adjustment set screw.

[0015] Optionally, the laser annealing apparatus includes:

[0016] An industrial control computer is connected to the light homogenizing and shaping module. The industrial control computer is equipped with an image quality compensation control system. Under the control of the image quality compensation control system, the adjustment unit adjusts the position of the diffraction optical unit in each degree of freedom, thereby adjusting the image quality of the light spot.

[0017] Optionally, the galvanometer module includes two galvanometers, and at least one of the galvanometers changes its rotation angle under the control of a motor, so that the laser beam reflected by the two galvanometers is focused by the focusing module to form a light spot on the focal plane.

[0018] Optionally, the laser annealing apparatus further includes:

[0019] A field lens module, which is used to adjust the size of the light spot and / or adjust the numerical aperture of the laser beam incident on the field lens module.

[0020] On the other hand, the present invention provides a laser annealing method, the method comprising:

[0021] A laser beam is provided and passes through a homogenizing and shaping module, a galvanometer module, and a focusing module to irradiate the surface of a workpiece to form a light spot. The homogenizing and shaping module has at least one degree of freedom. By adjusting the scanning angle of the galvanometer module, the position of the light spot can traverse various field points within the annealing range of the workpiece surface.

[0022] The image quality of the light spots formed at each field of view is evaluated, and based on the evaluation results, the position of the homogenizing and shaping module in the degree of freedom is changed to make the image quality of the light spots meet the requirements. The adjustment amount corresponding to each field of view is recorded and saved; and

[0023] Laser annealing is performed, wherein, based on the position of each field point, an appropriate adjustment amount is selected, and the position of the uniform light shaping module is adjusted synchronously to compensate for the image quality of the light spot formed at each field point.

[0024] The laser annealing apparatus provided by the present invention includes a galvanometer module, a focusing module, and a beam homogenization and shaping module. The galvanometer module includes a galvanometer, and the laser beam incident on the galvanometer module changes its exit position by rotating the galvanometer. The focusing module is used to focus the laser beam exiting from the galvanometer module to form a light spot on the focal plane. The beam homogenization and shaping module has at least one degree of freedom, and the image quality of the light spot can be adjusted by changing the position of the beam homogenization and shaping module in the degree of freedom. Since the homogenizing and shaping module has at least one degree of freedom, its position and / or orientation are adjustable. This allows for the improvement of spot deformation and image quality degradation caused by changes in the galvanometer scanning angle by altering the module's position in that degree of freedom. In other words, image quality compensation for the output spot is achieved, resulting in higher image quality of the spots formed at each field of view within the annealing range. For example, image quality compensation makes the light energy within each spot range more uniform, and the shapes of each spot are the same or similar, improving the annealing effect of the laser annealing device. Furthermore, since the image quality of the spots at each field of view is high, meaning that the spots at each field of view can be used for laser annealing, the range of a single annealing scan performed by the laser annealing device can be expanded. This improves the laser annealing efficiency and enhances the annealing capability of the laser annealing device when performing laser annealing over a larger area.

[0025] The laser annealing method evaluates the image quality of the light spots formed at each field of view, and changes the position of the homogenizing and shaping module in the degree of freedom based on the evaluation results, recording and saving the adjustment amount corresponding to each field of view. During laser annealing, the position of the homogenizing and shaping module is adjusted synchronously according to the position of each field of view to compensate for the image quality of the light spots formed at each field of view. This can improve the phenomenon of light spot deformation and image quality deterioration caused by changes in the galvanometer scanning angle, and improve the efficiency and effect of laser annealing. Attached Figure Description

[0026] Figure 1 A simulation diagram of the light spot formed at the first scanning field of view using an existing laser annealing device.

[0027] Figure 2 This is a simulation diagram of the light spot formed at the second scanning field of view using an existing laser annealing device.

[0028] Figure 3 A simulation of the light spot formed at the third scanning field of view using an existing laser annealing device.

[0029] Figure 4 This is a simulation of the light spots formed in different regions of the same field of view using an existing laser annealing device.

[0030] Figure 5 This is a schematic diagram of a laser annealing apparatus in one embodiment of the present invention.

[0031] Figure 6 This is a schematic diagram of the uniform shaping module and industrial control computer of a laser annealing apparatus according to an embodiment of the present invention.

[0032] Figure 7 This is a schematic diagram of the uniform beam shaping module and the industrial control computer of the laser annealing apparatus according to another embodiment of the present invention.

[0033] Figure 8 This is a schematic diagram of a laser annealing apparatus in another embodiment of the present invention.

[0034] Figure 9 A process flow diagram for performing laser annealing using a laser annealing method according to an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 101-Uniform beam shaping module; 1011-Mirror mount; 1012-Adjustment assembly; 102-Galvanometer module; 1021-Galvanometer; 103-Focusing module; 104-Workpiece stage; 105-Industrial computer; 106-Field lens module. Detailed Implementation

[0037] The laser annealing apparatus and laser annealing method proposed in this invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this invention.

[0038] Figure 1 A simulation diagram of the light spot formed at the first scanning field of view using an existing laser annealing device. Figure 2 This is a simulation diagram of the light spot formed at the second scanning field of view using an existing laser annealing device. Figure 3 This is a simulation of the light spot formed at the third scanning field of view using an existing laser annealing device. The inventors discovered that, as... Figure 1 As shown, the laser annealing device forms a regular square shape at the first scanning field of view (located in the central field of view), without deformation. The diagonal length L0 of this spot in the first direction (from the lower left corner to the upper right corner) is 156 μm. Figure 2 As shown, the distance from the second scanning field of view to the central field of view is the first distance. The diagonal length L1.1 of the light spot formed by the laser annealing device at the second scanning field of view in the first direction is 157 μm, and the diagonal length L1.2 in the second direction (from the lower right corner to the upper left corner) is 169 μm. L1.1 is less than L1.2, that is, the light spot at the second scanning field of view has been deformed relative to the first scanning field of view. Figure 3 As shown, the distance between the third scanning field of view and the central field of view is the second distance, and the second distance is greater than the first distance. That is, the distance from the third scanning field of view to the central field of view is farther than that from the second scanning field of view. The diagonal length L2.1 of the light spot formed by the laser annealing device at the third scanning field of view is 154μm in the first direction and 170μm in the second direction. L2.1 is less than L2.2, that is, the light spot at the third scanning field of view is also deformed relative to the first scanning field of view, and the deformation of the light spot at the third scanning field of view is greater than that at the second scanning field of view.

[0039] Figure 4 This is a simulation of the light spots formed in different regions of the same field of view using an existing laser annealing device. Figure 4 As shown, under the same field of view, the spot morphology formed by the laser annealing device at different field points is affected by the change in the galvanometer scanning angle. The spot formed at the edge of the field of view is more prone to deformation and has a more uneven energy distribution than the spot formed at the center of the field of view. It should be understood that the edge and center fields of view are within the same field of view, with the edge field of view deviating from the center of the field of view; that is, the edge field of view is located around the periphery of the center field of view.

[0040] In other words, when using existing laser annealing equipment, the energy of the laser beam scanned through the workpiece surface within the annealing range is not uniform at different field points. In particular, compared with the center field of view, the spot formed at the edge field of view has greater deformation and uneven energy, resulting in poor spot image quality. When the image quality is poor to a certain extent, it cannot meet the process requirements. At this point, it is necessary to reduce the effective range of the field of view, which leads to a decrease in the efficiency of laser annealing and an increase in the cost of laser annealing.

[0041] In order to improve the phenomenon of spot deformation and image quality deterioration caused by changes in the scanning angle of the galvanometer, especially to improve the spot image quality at the edge of the field of view, so as to improve the efficiency and effect of laser annealing, this embodiment first provides a laser annealing device.

[0042] Figure 5 This is a schematic diagram of a laser annealing apparatus according to an embodiment of the present invention. Figure 5 As shown, the laser annealing device includes a homogenizing and shaping module 101, a galvanometer module 102, and a focusing module 103. The galvanometer module 102 includes a galvanometer 1021. The laser beam incident on the galvanometer module 102 changes its exit position by rotating the galvanometer 1021. The focusing module 103 is used to focus the laser beam emitted from the galvanometer module 102 to form a light spot on the focal plane. The homogenizing and shaping module 101 has at least one degree of freedom. The image quality of the light spot can be adjusted by changing the position of the homogenizing and shaping module in the degree of freedom.

[0043] A galvanometer module is an excellent vector scanning device and a special type of oscillating motor. Unlike ordinary motors, it cannot rotate but can only deflect. The deflection angle is controlled by the current flowing through the coil in the galvanometer module, and this deflection angle is directly proportional to the flowing current. Specifically, for example... Figure 5 As shown, the galvanometer module 102 may include two galvanometers 1021, and at least one of the galvanometers 1021 changes its rotation angle (deflection angle) under the control of a motor, so that the laser beam reflected by the two galvanometers is focused by the focusing module 103 to form a light spot on the focal plane. In other words, by controlling the deflection angle of each galvanometer in the galvanometer module, the laser beam incident on the galvanometer module 102 can be projected onto a specified position of the annealing range on the workpiece surface.

[0044] It should be understood that the laser annealing apparatus may also include a workpiece stage. For example... Figure 5 As shown, a workpiece (not shown) is placed on a workpiece stage 104, and the light spot output by the focusing module 103 is swept onto the surface of the workpiece to perform laser annealing. The focusing module 103 may include a flat-field focusing lens (F-theta focusing lens).

[0045] In one embodiment, the homogenizing and shaping module 101 is disposed upstream of the galvanometer module 102. Specifically, the homogenizing and shaping module may have a first degree of freedom of translation along a first direction (e.g., Figure 6 (Dy) and / or a second degree of freedom (e.g., translation along a second direction perpendicular to the first direction) and / or translation along a second direction perpendicular to the first direction. Figure 6 The plane formed by the first direction and the second direction can be perpendicular to the direction of the laser beam incident on the homogenizing and shaping module 101. The homogenizing and shaping module 101 may also have a third degree of freedom (e.g., rotation about the first direction as an axis). Figure 7 (Ry), and / or a fourth degree of freedom (e.g., rotation about a second direction perpendicular to the first direction) Figure 7 In the first direction (Rz), the plane formed by the first direction and the second direction can be perpendicular to the direction of the laser beam incident on the homogenizing and shaping module 101. That is, the homogenizing and shaping module 101 can adjust the image quality of the light spot by translating in the first and second directions, and / or rotating about the first and second directions as axes, thus achieving flexible adjustment of the image quality of the light spot output by the laser annealing device. Specifically, the image quality of the light spot can be adjusted by translating the homogenizing and shaping module 101 in the first and / or second directions, or by rotating the homogenizing and shaping module 101 about the first and / or second directions as axes. In another embodiment, the image quality of the light spot can be adjusted by translating the homogenizing and shaping module in the first and second directions and rotating it about the first and second directions as axes.

[0046] In this embodiment, since the homogenizing and shaping module 101 has at least one degree of freedom, its position and / or orientation are adjustable. Therefore, by changing the position of the homogenizing and shaping module in each degree of freedom, precise compensation can be made to the image quality of the light spot output by the laser annealing device, especially for the light spot in the edge field of view. This ensures that the energy of the light spot in the edge field of view is more uniform and its shape is the same as or similar to that of the light spot in the center field of view, thereby improving the annealing efficiency and effect of the laser annealing device. In this embodiment, the image quality of the light spot can include the energy uniformity and shape of the light spot. For example, when the energy of the light spot is relatively uniform and the shape meets the requirements (no deformation or small deformation), the image quality of the light spot is high; when the energy uniformity of the light spot is poor and the shape does not meet the requirements (large deformation), the image quality of the light spot is poor.

[0047] Specifically, the homogenizing and shaping module may include a diffraction optical unit and an adjustment unit, wherein the adjustment unit is used to adjust the position of the diffraction optical unit in each degree of freedom.

[0048] It should be noted that the diffraction optical unit can be an entire optical system used to homogenize and shape the laser beam incident on the galvanometer module 102, and the adjustment unit can make minor adjustments to the orientation of the entire optical system. The diffraction optical unit may include at least one diffraction optical element (DOE).

[0049] Figure 6 This is a schematic diagram of the uniform shaping module and industrial control computer of a laser annealing apparatus according to an embodiment of the present invention. Figure 7 This is a schematic diagram of the uniform beam shaping module and industrial control computer of a laser annealing apparatus according to another embodiment of the present invention. Figure 6 and Figure 7 As shown, the laser annealing device may further include an industrial control computer 105, which is connected to the homogenizing and shaping module 101. The industrial control computer 105 is equipped with an image quality compensation control system. Under the control of the image quality compensation control system, the adjustment unit adjusts the position of the diffractive optical unit in each degree of freedom, thereby adjusting the image quality of the light spot. The homogenizing and shaping module 101 may include a mirror mount 1011. The diffractive optical unit may be disposed on the mirror mount 1011 and move with the mirror mount 1011. The adjustment unit includes multiple adjustment components 1012 connected to the mirror mount. Each adjustment component 1012 adjusts the position of the diffractive optical unit in one degree of freedom by adjusting the position of the mirror mount 1011.

[0050] Specifically, each of the adjustment components 1012 can be controlled independently. That is, one adjustment component can be controlled individually to adjust the diffractive optical unit, thereby adjusting the position of the homogenizing and shaping module 101 in one degree of freedom. Alternatively, multiple adjustment components can be controlled to adjust the diffractive optical unit, thereby adjusting the position of the homogenizing and shaping module in multiple degrees of freedom. In other words, each adjustment component corresponds to one degree of freedom of the homogenizing and shaping module and can be used to adjust the translation (eccentricity) or deflection angle (tilt angle) of the diffractive optical unit in a certain direction within the homogenizing and shaping module. For example, the laser annealing device may include four adjustment components, two of which are used to adjust the translation of the diffraction optical unit in the first and second directions, and two of which are used to adjust the deflection angle of the diffraction optical unit about the first and second directions as axes. The adjustment amounts of each component can be adjusted under the control of the image quality compensation system within the industrial control computer 105 to adjust the translation and deflection angle of the diffraction optical unit, thereby achieving positional adjustment of the homogenizing and shaping module in each degree of freedom and realizing image quality compensation for the output spot of the laser annealing device (specifically, the spot output by the focusing module). Optionally, the adjustment component 1012 may include an adjustment set screw. The adjustment set screw can be screwed to the mirror base or connected to the mirror base through other connection methods, as long as it can achieve the function of adjusting the translation or deflection angle of the diffraction optical unit.

[0051] As an example, such as Figure 6 As shown, the adjustment unit may include two adjustment components 1012. Both adjustment components 1012 are connected to the lens mount 1011 and can be connected to the industrial control computer 105 via a motor. Under the control of the image quality compensation control system (software) within the industrial control computer, the translation amount (eccentricity) of the diffraction optical unit in the first direction (Y direction) and the second direction (Z direction) can be adjusted by controlling the two adjustment components 1012. Figure 7 As shown, the adjustment unit may also include two other adjustment components 1012. Both adjustment components 1012 are connected to the lens mount 1011 and are connected to the industrial control computer 105 via a motor. Under the control of the image quality compensation control system (software) in the industrial control computer, the two adjustment components 1012 can be controlled to adjust the deflection angle of the diffraction optical unit with the first direction (Y direction) and the second direction (Z direction) as axes, respectively.

[0052] Figure 8 This is a schematic diagram of a laser annealing apparatus according to another embodiment of the present invention. Figure 8As shown, the laser annealing apparatus may further include a field lens module 106. In one embodiment, the field lens module 106 is located downstream of the homogenizing and shaping module 101 and upstream of the galvanometer module 102. The galvanometer module 106 can be used to adjust the size of the light spot and / or adjust the numerical aperture of the laser beam incident on the field lens module. The homogenizing and shaping module 101 and the field lens 106 can be set independently. However, in another embodiment, the homogenizing and shaping module 101 and the field lens module 106 can also be integrated on the front and rear surfaces of the same component (called an integrated module) to simplify the structure of the laser annealing apparatus and save space. In this case, after the laser beam passes through the integrated module, it can achieve the effect of homogenizing and shaping the incoming laser beam, while simultaneously adjusting the size of the output light spot of the laser annealing apparatus or adjusting the numerical aperture of the laser beam incident on the field lens module.

[0053] The laser annealing apparatus provided by this invention includes a galvanometer module, a focusing module, and a beam homogenization and shaping module. The galvanometer module includes a galvanometer, and the laser beam incident on the galvanometer module changes its exit position through rotation of the galvanometer. The focusing module focuses the laser beam exiting the galvanometer module to form a spot on the focal plane. The beam homogenization and shaping module has at least one degree of freedom, and the image quality of the spot can be adjusted by changing the position of the beam homogenization and shaping module in that degree of freedom. Since the beam homogenization and shaping module has at least one degree of freedom, for example, the beam homogenization and shaping module 101 can translate in a first direction and a second direction, and / or rotate about the first direction and the second direction as axes, the position and / or orientation of the beam homogenization and shaping module is adjustable. Therefore, by changing the position of the beam homogenization and shaping module in each degree of freedom, the deformation and image quality deterioration of the spot (especially the spot formed at the edge of the field of view) caused by changes in the galvanometer scanning angle can be improved, thus achieving image quality compensation for the output spot, so that within the annealing range, each field point forms a spot. The laser annealing device has high image quality. For example, through image quality compensation, the light energy within each spot range is more uniform, and the shapes of each spot are the same or similar, which improves the annealing effect of the laser annealing device. Moreover, since the image quality of the spot at each field of view is high, that is, the spot at each field of view can be used for laser annealing, the range of single annealing scans of the laser annealing device can be expanded. Thus, when performing laser annealing on a large area, the number of laser scans can be reduced, thereby improving the laser annealing efficiency and reducing the laser annealing cost, and enhancing the annealing capability of the laser annealing device.

[0054] This embodiment also provides a laser annealing method, which can use the above-mentioned laser annealing device to perform laser annealing on a workpiece. The laser annealing method includes: providing a laser beam, and passing the laser beam through a homogenizing and shaping module, a galvanometer module, and a focusing module to irradiate the surface of the workpiece to form a light spot, wherein the homogenizing and shaping module has at least one degree of freedom, and by adjusting the scanning angle of the galvanometer module, the position of the light spot traverses each field of view within the annealing range of the workpiece surface; simultaneously, evaluating the image quality of the light spot formed at each field of view, and, based on the evaluation result, changing the position of the homogenizing and shaping module in the degree of freedom to make the image quality of the light spot meet the requirements, and recording and saving the adjustment amount corresponding to each field of view; and then performing laser annealing, wherein, according to the position of each field of view, the position of the homogenizing and shaping module is synchronously adjusted by selecting the corresponding adjustment amount to compensate for the image quality of the light spot formed at each field of view.

[0055] Specifically, evaluating the image quality of the light spots formed at each field of view may include assessing the shape and energy uniformity of the light spots. The homogenizing module may include a mirror mount, a diffractive optical unit, and an adjustment unit, and the adjustment unit may include multiple adjustment components connected to the mirror mount. Changing the position of the homogenizing module in the degree of freedom may include adjusting the adjustment components to adjust the translation or deflection angle of the diffractive optical unit. The recorded adjustment amount may include recording the translation and / or deflection angle of the diffractive optical unit.

[0056] Figure 9 A process flow diagram illustrating the laser annealing process performed using a laser annealing method according to an embodiment of the present invention is provided. Figure 9 As shown, as an example, the laser annealing process can include the following steps: the operator issues a command to the laser annealing device to start annealing, and then the industrial control computer in the laser annealing device issues a process command. Under the control of the process command, each functional module of the laser annealing device performs actions related to the laser annealing process, which can cause a laser beam to pass through the homogenizing and shaping module, the galvanometer module, and the focusing module in sequence, and irradiate the workpiece surface located on the focal plane of the focusing module to form a light spot.

[0057] The process instructions include path instructions. Under the control of the path instructions, the galvanometer in the galvanometer module changes its deflection angle, and the focusing module and the galvanometer module cooperate to move the light spot on the workpiece surface. At the same time, under the control of the path instructions, the image quality compensation control system in the industrial computer selects the corresponding adjustment amount according to the position of the formed light spot (the field point coordinates corresponding to the light spot) to synchronously adjust the position of the uniform light shaping module (i.e., adjust the adjustment path corresponding to the diffraction optical unit) so that the image quality of the light spot irradiated on the workpiece meets the requirements. After the light spot traverses each field point within the annealing range of the workpiece surface, the laser annealing process ends.

[0058] The laser annealing method of this embodiment evaluates the image quality of the light spots formed at each field of view, and selectively adjusts the position of the homogenizing and shaping module at each degree of freedom based on the evaluation results, and records and saves the adjustment amount corresponding to each field of view. When performing laser annealing, the position of the homogenizing and shaping module is adjusted synchronously according to the position of each field of view to compensate for the image quality of the light spots formed at each field of view. This can improve the phenomenon of light spot deformation and image quality deterioration caused by changes in the galvanometer scanning angle, and improve the efficiency and effect of laser annealing.

[0059] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A laser annealing apparatus, characterized in that, include: A galvanometer module includes a galvanometer, and the laser beam incident on the galvanometer module changes its exit position by rotating the galvanometer. A focusing module is used to focus the laser beam emitted from the galvanometer module to form a light spot on the focal plane; A homogenizing and shaping module has at least one degree of freedom. The image quality of the light spot is adjusted by changing the position of the homogenizing and shaping module in that degree of freedom. The homogenizing and shaping module includes a diffractive optical element and an adjustment unit. The adjustment unit adjusts the position of the diffractive optical element in each degree of freedom to compensate for the light spot in the edge field of view, making the light spot shapes in the edge field of view and the center field of view identical. The diffractive optical element has a first degree of freedom of translation along a first direction and / or a second degree of freedom of translation along a second direction perpendicular to the first direction. The adjustment unit adjusts the eccentricity of the diffractive optical element in the first direction and / or the second direction to compensate for the light spot in the edge field of view. The plane formed by the first direction and the second direction is perpendicular to the direction of the laser beam incident on the homogenizing and shaping module.

2. The laser annealing apparatus as described in claim 1, characterized in that, The uniform light shaping module has a third degree of freedom of rotation about a first direction as an axis, and / or a fourth degree of freedom of rotation about a second direction perpendicular to the first direction as an axis.

3. The laser annealing apparatus as described in claim 1, characterized in that, The homogenizing and shaping module also includes a mirror mount, on which the diffractive optical unit is disposed and moves with the mirror mount. The adjustment unit includes multiple adjustment components connected to the mirror mount, and each adjustment component adjusts the position of the diffractive optical unit in one degree of freedom by adjusting the position of the mirror mount.

4. The laser annealing apparatus as described in claim 3, characterized in that, The adjustment assembly includes an adjustment set screw.

5. The laser annealing apparatus as described in claim 1, characterized in that, The laser annealing device includes: An industrial control computer is connected to the light homogenizing and shaping module. The industrial control computer is equipped with an image quality compensation control system. Under the control of the image quality compensation control system, the adjustment unit adjusts the position of the diffraction optical unit in each degree of freedom, thereby adjusting the image quality of the light spot.

6. The laser annealing apparatus as described in claim 1, characterized in that, The galvanometer module includes two galvanometers, and at least one of the galvanometers changes its rotation angle under the control of a motor, so that the laser beam reflected by the two galvanometers is focused by the focusing module to form a light spot on the focal plane.

7. The laser annealing apparatus as described in claim 1, characterized in that, The laser annealing apparatus also includes: A field lens module is used to adjust the size of the light spot and / or adjust the numerical aperture of the laser beam incident on the field lens module.

8. A laser annealing method, characterized in that, Laser annealing is performed using the laser annealing apparatus as described in any one of claims 1 to 7, wherein the laser annealing method comprises: A laser beam is provided and passes through a homogenizing and shaping module, a galvanometer module, and a focusing module to irradiate the surface of a workpiece to form a light spot. The homogenizing and shaping module has at least one degree of freedom. By adjusting the scanning angle of the galvanometer module, the position of the light spot can traverse various field points within the annealing range of the workpiece surface. The image quality of the light spots formed at each field of view is evaluated, and based on the evaluation results, the position of the homogenizing and shaping module in the degree of freedom is changed to make the image quality of the light spots meet the requirements. The adjustment amount corresponding to each field of view is recorded and saved; and Laser annealing is performed, wherein, based on the position of each field point, the position of the uniform light shaping module is adjusted synchronously by selecting the corresponding adjustment amount to compensate for the image quality of the light spot formed at each field point.

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