Laser annealing device and laser annealing equipment

Abstract

The utility model discloses a laser annealing device and laser annealing equipment, and relates to the technical field of laser annealing, the laser annealing device comprises a laser, a beam expanding module, a light equalizing module and a focusing module, the laser is used for outputting laser beams; the beam expanding module is used for expanding the laser beams; the light homogenizing module comprises a DOE homogenizing mirror and a Dove prism, the DOE homogenizing mirror is used for homogenizing the laser beams output by the beam expanding module, and the Dove prism is used for rotating light spots of the laser beams output by the DOE homogenizing mirror; the focusing module is used for focusing light spots of the laser beams output by the Dove prism. The utility model aims to ensure that the heating time of each area on the surface of a material is equalized, so that the problem of overheating or underheating caused by local energy accumulation is effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of laser annealing technology, and in particular to a laser annealing apparatus and laser annealing equipment. Background Technology

[0002] Laser annealing is a technique that uses a high-energy laser beam to locally and rapidly heat the surface of a material. By precisely controlling the energy input and the treatment time, it induces processes such as phase transformation, grain refinement, defect repair, or stress release in the material. Its core advantages are non-contact processing, high energy density, and high spatial resolution, and it is widely used in semiconductors, metals, nanomaterials, and photovoltaics.

[0003] Laser spot uniformity refers to the consistency of laser energy distribution in the target area, and is one of the key factors for the success or failure of laser annealing. Currently, beam shaping techniques, such as diffractive optical elements (DOEs) and wavefront correction systems, are generally used to generate uniform laser spots. However, during long-term production, due to fluctuations in laser stability, equipment stability, and environmental conditions, local variations in the laser spot are inevitable, leading to a decrease in the uniformity of the annealing effect. Utility Model Content

[0004] The main purpose of this invention is to provide a laser annealing device and laser annealing equipment, which aims to ensure that the heating time of each area on the material surface is equal, thereby effectively reducing the overheating or underheating problems caused by local energy accumulation.

[0005] To achieve the above objectives, this utility model proposes a laser annealing device, comprising:

[0006] A laser, the laser being used to output a laser beam;

[0007] A beam expander module, used to expand the laser beam;

[0008] A beam homogenization module, comprising a DOE homogenizer and a Dove prism, wherein the DOE homogenizer is used to homogenize the laser beam output from the beam expander module, and the Dove prism is used to rotate the spot of the laser beam output from the DOE homogenizer; and

[0009] A focusing module is used to focus the laser beam output from the Daowei prism into a spot.

[0010] In one embodiment, the beam homogenization module further includes a hollow shaft motor and a prism mount. The Daowei prism is fixed inside the hollow shaft motor via the prism mount. The hollow shaft motor is used to drive the prism mount to rotate the Daowei prism along the optical axis of the laser beam.

[0011] In one embodiment, the rotational speed of the Dowell prism is v, where 1000rpm≤v≤10000rpm.

[0012] In one embodiment, the axial section of the Dowell prism is an isosceles trapezoid.

[0013] In one embodiment, the beam expander module includes a beam expander lens, which includes a confocal concave lens and a convex lens.

[0014] In one embodiment, the laser annealing apparatus further includes a temperature monitoring module for monitoring the surface temperature of the material irradiated by the laser spot; and / or

[0015] The laser annealing apparatus also includes an energy sensor, which is used to monitor the energy distribution of the light spot on the surface of the material.

[0016] In one embodiment, the laser annealing apparatus further includes an image positioning system, which is configured in conjunction with the focusing module to position and focus the light spot onto the working surface.

[0017] In one embodiment, the image positioning system includes a CCD module, a telecentric lens, and an LED light source, wherein the CCD module is mounted on the telecentric lens, and the LED light source is located on the outer edge of either side of the telecentric lens.

[0018] This utility model also provides a laser annealing device, including the laser annealing apparatus as described above.

[0019] The laser annealing apparatus provided in this application outputs a laser beam from a laser, which is then effectively expanded by a beam expander module to ensure that the beam covers the required processing area. Subsequently, the laser beam enters a homogenizing module. The DOE homogenizing mirror in this module, based on the principle of diffraction optics, can transform the originally non-uniform laser energy distribution (such as a Gaussian spot) into a highly uniform flat-top spot, thereby significantly improving energy utilization and processing quality. The homogenized spot is further processed by a Dowell prism for rotation. The Dowell prism, as a special optical element, can change the direction of the light path or achieve image rotation. When the prism rotates along its longitudinal axis, the passing spot will rotate at twice the rotational speed of the prism. This high-speed rotation mechanism not only effectively homogenizes the heat distribution but also further improves the uniformity of the processing effect. Thus, by rotating the trajectory of the laser spot, the heating time of each area on the material surface can be ensured to be equalized, thereby effectively reducing overheating or underheating problems caused by local energy accumulation. In summary, the laser annealing apparatus provided in this application achieves uniform energy distribution through DOE homogenization and rotational homogenization, which not only improves the energy utilization rate and processing accuracy of the laser annealing process, but also significantly improves the uniformity and stability of the processing quality. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a laser annealing device provided in an embodiment of the present invention.

[0022] Explanation of icon numbers:

[0023] 100. Laser annealing apparatus; 1. Laser; 2. Beam expander; 3. DOE mirror; 4. Dove prism; 5. Reflector; 6. Focusing lens; 7. Silicon wafer.

[0024] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0027] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0028] This application provides a laser annealing apparatus 100.

[0029] In one embodiment of this application, the laser annealing apparatus 100 includes a laser 1, a beam expander module, a beam homogenizing module, and a focusing module. The laser 1 is used to output a laser beam; the beam expander module is used to expand the laser beam; the beam homogenizing module includes a DOE homogenizer and a Dove prism 4. The DOE homogenizer is used to homogenize the laser beam output by the beam expander module, and the Dove prism 4 is used to rotate the spot of the laser beam output by the DOE homogenizer; the focusing module is used to focus the spot of the laser beam output by the Dove prism 4.

[0030] The laser annealing apparatus 100 provided in this application outputs a laser beam from a laser 1, which is then effectively expanded by a beam expander module to ensure that the beam covers the required processing area. Subsequently, the laser beam enters a homogenizing module. The DOE homogenizing mirror in this module, based on the principle of diffraction optics, can transform the originally non-uniform laser energy distribution (such as a Gaussian spot) into a highly uniform flat-top spot, thereby significantly improving energy utilization and processing quality. The homogenized spot is further rotated by a Dowell prism 4. As a special optical element, the Dowell prism 4 can change the direction of the light path or achieve image rotation. When the prism rotates along the longitudinal axis, the passing spot will rotate at twice the rotation speed of the prism. This high-speed rotation mechanism not only effectively homogenizes the heat distribution but also further improves the uniformity of the processing effect. Thus, by rotating the trajectory of the laser spot, it is possible to ensure that the heating time of each area on the material surface is equalized, thereby effectively reducing overheating or underheating problems caused by local energy accumulation. In summary, the laser annealing apparatus 100 provided in this application achieves uniform energy distribution through DOE homogenization and rotational homogenization, which not only improves the energy utilization rate and processing accuracy of the laser annealing process, but also significantly improves the uniformity and stability of the processing quality.

[0031] In one embodiment, the laser annealing apparatus 100 further includes a 45-degree reflector 5 disposed on the laser beam propagation path. The 45-degree reflector is mainly used for adjusting the path of the light beam, and its reflectivity is greater than 98%. Depending on the need to change the light beam propagation path, the 45-degree reflector can be arbitrarily positioned on the beam propagation path. Of course, multiple 45-degree reflectors can also be provided according to the needs of path adjustment.

[0032] In one embodiment, the beam homogenization module further includes a hollow shaft motor and a prism mount. The Daowei prism 4 is fixed inside the hollow shaft motor via the prism mount. The hollow shaft motor drives the prism mount to rotate the Daowei prism 4 along the optical axis of the laser beam. The hollow shaft motor is a special type of motor with a hollow shaft, allowing the laser beam to pass through the motor shaft without interfering with the optical path. The hollow shaft motor and prism mount structure provide stable and precise drive for the rotation of the Daowei prism 4, enhancing the beam homogenization effect, processing accuracy, and stability of the laser annealing device 100, and providing strong support for high-quality, high-efficiency laser processing.

[0033] To more quickly homogenize the laser beam, in one embodiment, the rotational speed of the Daowei prism 4 is v, where 1000 rpm ≤ v ≤ 10000 rpm. For applications that do not require high-speed processing, lower rotational speeds can reduce mechanical wear and energy consumption, while high-speed rotation can accelerate laser scanning speed and improve processing efficiency, making it suitable for mass production. Within the set rotational speed range, the design of the hollow shaft motor and prism mount not only ensures the stable rotation of the Daowei prism 4, reducing vibration and sway, but also guarantees a stable homogenization effect for the laser beam, improving processing consistency.

[0034] In one embodiment, the axial section of the Dowell prism 4 is an isosceles trapezoid. This design allows the laser beam to undergo two total internal reflections inside the prism, enabling a 180° image flip.

[0035] In one embodiment, the beam expanding module includes a beam expander 2, which comprises a confocal concave lens and a convex lens. First, the laser beam passes through the concave lens, causing the beam to diverge. The focal point of the concave lens is located at the focal point of the convex lens, allowing the diverged beam to refocus at its focal point upon entering the convex lens. Then, the diverged beam passes through the convex lens again, refocusing and forming a parallel beam. This expands the size of the laser beam and compresses the divergence angle, thus achieving a beam expanding effect. In other embodiments, the beam expanding module may also include beam shaping elements, filters, polarization controllers, and mechanical adjustment mechanisms. These components work together to meet the requirements of different application scenarios regarding beam shape, distribution, wavelength, polarization, diameter, collimation, stability, power, dynamic positioning, and temperature control.

[0036] In one embodiment, the laser annealing apparatus 100 further includes a temperature monitoring module for monitoring the surface temperature of the material (silicon wafer 7) irradiated by the laser spot. The temperature monitoring module typically includes temperature sensors such as an infrared thermometer, thermal imager, or thermocouple, capable of real-time monitoring of the material surface temperature irradiated by the laser spot to ensure annealing temperature control and to ensure the material surface temperature reaches the set annealing temperature, avoiding overheating or underheating. In actual operation, parameters such as laser power and scanning speed can be adjusted based on temperature feedback to optimize the annealing process.

[0037] In one embodiment, the laser annealing apparatus 100 further includes an energy sensor for monitoring the energy distribution of the laser spot on the material surface. In this embodiment, the energy sensor is typically an energy meter, optical power meter, or a dedicated energy distribution measurement device, capable of monitoring the energy distribution of the laser spot on the material surface. This real-time monitoring ensures that the laser energy is evenly distributed on the material surface, preventing uneven annealing caused by excessively high or low energy levels. During actual operation, the operating parameters of the laser emission system, beam expander module, etc., can be adjusted based on the energy distribution feedback to obtain the optimal annealing effect.

[0038] In one embodiment, the laser annealing apparatus 100 further includes an image positioning system, which works in conjunction with the focusing module to position and focus the laser spot onto the working surface. In this embodiment, the image positioning system provides real-time position information of the laser spot, and the focusing module makes rapid adjustments based on this information. The two work together through a control system to ensure that the laser spot is always precisely focused on the working surface of the material throughout the annealing process, greatly improving the positioning accuracy and efficiency of the laser spot and avoiding errors from manual positioning.

[0039] In one embodiment, the image positioning system includes a CCD module, a telecentric lens, and an LED light source. The CCD module is mounted on the telecentric lens, and the LED light source is located on the outer edge of either side of the telecentric lens. In this embodiment, the CCD module, as the core component for image acquisition, is responsible for capturing high-resolution images of the material surface. The telecentric lens is a specially designed optical lens that ensures minimal image distortion and provides uniform illumination, which is beneficial for subsequent image processing and positioning calculations. The LED light source is located on the outer edge of either side of the telecentric lens, thus preventing direct illumination of the lens, reducing glare and reflection, and improving image quality.

[0040] This utility model also provides a laser annealing device, including a laser annealing apparatus 100. The specific structure and installation method of the laser annealing apparatus 100 are as described in the above embodiments. Since the laser annealing device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here.

[0041] It should be noted that laser annealing equipment typically refers to a complete, integrated system, including multiple components such as laser 1, control system, mechanical structure, cooling system, and safety protection devices. It is an independent, self-contained working unit. Laser annealing device 100, on the other hand, focuses more on the core components or modules of laser annealing, such as laser 1, optical system, and focusing module. It is part of the laser annealing equipment but can also be integrated into other equipment as an independent functional module.

[0042] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the inventive concept of this utility model and the contents of the specification and drawings of this utility model, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.

Claims

1. A laser annealing apparatus characterized by comprising: The laser annealing device comprises: a laser for outputting a laser beam; a beam expanding module for expanding the laser beam; a homogenizing module comprising a DOE homogenizing mirror for homogenizing the laser beam output by the beam expanding module and a Dove prism for rotating the spot of the laser beam output by the DOE homogenizing mirror; and a focusing module for focusing the spot of the laser beam output by the Dove prism.

2. The laser anneal apparatus of claim 1, wherein, The homogenizing module further comprises a hollow shaft motor and a prism seat, the Dove prism being fixed in the hollow shaft motor through the prism seat, the hollow shaft motor being used to drive the prism seat to rotate the Dove prism along the optical axis of the laser beam.

3. The laser anneal apparatus of claim 2, wherein, The rotation speed of the Dove prism is v, 1000 rpm≤v≤10000 rpm.

4. The laser anneal apparatus of claim 1, wherein, The shape of the axial section of the Dove prism is isosceles trapezoidal.

5. The laser anneal apparatus of claim 1, wherein, The beam expanding module comprises a beam expanding mirror comprising a concave lens and a convex lens arranged in a confocal manner.

6. The laser anneal apparatus of claim 1, wherein, The laser annealing device further comprises a temperature monitoring module for monitoring the surface temperature of the material irradiated by the spot; and / or The laser annealing device further comprises an energy sensor for monitoring the energy distribution of the spot on the surface of the material.

7. The laser anneal apparatus of claim 1, wherein, The laser annealing device further comprises an image positioning system cooperatively arranged with the focusing module to position and focus the spot to the action surface.

8. The laser anneal apparatus of claim 7, wherein, The image positioning system comprises a CCD module, a telecentric lens and an LED light source, wherein the CCD module is sleeved on the telecentric lens, and the LED light source is arranged at the outer edge of either side of the telecentric lens.

9. A laser anneal apparatus, comprising: The laser annealing device as claimed in any one of claims 1 to 8. The laser annealing device as claimed in any one of claims 1 to 8.

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