Laser annealing device and laser annealing method using same

Abstract

The invention discloses a laser annealing device and a laser annealing method.The laser annealing device comprises a light source module, a beam expanding module, a shaping module, a scanning module, a control module and a visual detection module, the light source module generates a first light beam, and the beam expanding module adjusts the diameter of the first light beam and emits a second light beam; the shaping module shapes the second light beam into a shaped light beam, the scanning module comprises a scanning galvanometer and a scanning field lens, the scanning galvanometer reflects the shaped light beam, the scanning field lens focuses the shaped light beam and irradiates a flat-topped light spot in a first reaction area of the wafer, and the visual detection module obtains image information of the wafer; the control module determines an unreacted area of the wafer based on the image information, controls the scanning galvanometer to deflect, and irradiates a flat-topped light spot in the unreacted area; and when the silicification reaction is generated in the first reaction area, the control module can control the scanning galvanometer to deflect and irradiate flat-topped light spots in the second reaction area. Through the arrangement, the wafer laser annealing processing efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of laser annealing technology, and in particular to a laser annealing apparatus and a laser annealing method using the laser annealing apparatus. Background Technology

[0002] Wafer laser annealing is a key process in logic chip manufacturing. This process uses a high-power laser to generate a laser beam, which is then irradiated by multiple laser optical shaping and homogenizing systems with different functions at a working distance. Within a unit of time, the surface atoms of the wafer are heated to over 1000°C by the laser beam, followed by rapid cooling, causing a localized silanization reaction on the wafer surface to eliminate lattice defects. Lattice defects refer to the disruption and damage to the crystal structure caused by various factors (such as the injection of high-energy particles) during crystal growth and manufacturing. These defects impair the electrical properties of the material. Laser annealing can repair these lattice defects, allowing atoms to rearrange back to their correct positions in the lattice, thereby restoring the material's electrical properties and improving wafer yield.

[0003] The wafer is supported by a displacement stage. After silanization occurs in a reaction region on the wafer surface, the displacement stage moves the wafer a certain distance along the X-axis or Y-axis, allowing the next reaction region on the wafer surface to be irradiated by the laser spot and undergo silanization, until the entire wafer surface has undergone laser annealing. In some implementations, the efficiency of wafer laser annealing can be improved by increasing the displacement speed of the displacement stage. However, because the wafer laser annealing process requires a certain level of laser scanning accuracy, such as an error of no more than 1 μm, a higher displacement speed of the displacement stage is needed to meet this accuracy requirement. Under current hardware limitations, the displacement speed limit of the displacement stage is 2000 mm / s, which cannot meet the accuracy requirements of laser scanning. Therefore, such hardware limitations result in low efficiency of wafer laser annealing. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this application is to provide a laser annealing apparatus that can improve the efficiency of laser annealing of wafers and a laser annealing method using the laser annealing apparatus.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] In a first aspect, this application provides a laser annealing apparatus, comprising a displacement stage, a light source module, a beam expander module, a shaping module, a scanning module, a vision inspection module, and a control module. The displacement stage supports a wafer, the light source module generates a first beam, the beam expander module adjusts the diameter of the first beam to emit a second beam, the diameter of the second beam being larger than the diameter of the first beam, the shaping module receives the second beam and shapes it to form a shaped beam, the uniformity of the shaped beam being not less than a preset uniformity threshold, and the scanning module includes a scanning galvanometer and a scanning field mirror. The scanning galvanometer reflects the shaped beam and... The field-focusing mirror is used to focus the shaping beam emitted by the scanning galvanometer and illuminate a flat-topped light spot in the first reaction region of the wafer. The vision inspection module is used to acquire image information of the wafer. The control module is electrically connected to the vision inspection module. The control module can determine the unreacted region of the wafer based on the image information and control the deflection of the scanning galvanometer to illuminate the flat-topped light spot in the unreacted region of the wafer. When the first reaction region of the wafer undergoes a siliconization reaction under the action of the light spot, the control module controls the scanning galvanometer to deflect at a set angle and illuminate the flat-topped light spot in the second reaction region of the wafer. The positions of the first reaction region and the second reaction region are different.

[0007] In some possible implementations, the first reaction region and the second reaction region at least partially overlap.

[0008] In some possible implementations, both the first reaction region and the second reaction region include an annealed region and an unannealed region. The spot energy density received by the annealed region is greater than that received by the unannealed region, and the unannealed region surrounds the annealed region. The annealed region in the second reaction region overlaps with the unannealed region in the first reaction region.

[0009] In some possible implementations, the laser annealing apparatus also includes an attenuation module located in the optical path extending from the light source module to the beam expander module. The attenuation module is used to adjust the power of the first beam, and the control module can control the attenuation module to reduce the power of the first beam based on a preset energy density required for processing the wafer.

[0010] In some possible implementations, the attenuation module includes a half-wave plate, a polarizing element, and a beam collector. The half-wave plate is used to adjust the power of the first beam and transmit it to the polarizing element. The polarizing element is used to separate a portion of the beam from the first beam and transmit the separated portion of the beam to the beam collector.

[0011] In some possible implementations, the visual inspection module includes a displacement component and a camera component. The displacement component includes a guide rail and a connecting unit. The guide rail is located above the displacement stage, and the connecting unit is connected to the guide rail and can move relative to the guide rail along the extension direction of the guide rail. The camera component includes a visual camera and a telecentric lens. The telecentric lens is connected to the visual camera, and the visual camera is mounted on the connecting unit and can move relative to the guide rail under the drive of the connecting unit.

[0012] In some possible implementations, the laser annealing apparatus also includes a monitoring module electrically connected to the control module. The monitoring module is used to monitor the diameter or power of the second beam and send the monitoring signal characterizing the diameter or power of the second beam to the control module. The control module can control the attenuation module to adjust the power of the first beam based on the monitoring signal.

[0013] In some possible implementations, the monitoring module includes a first beam detector and a second beam detector. The first beam detector is located in the optical path extending from the self-expanding module to the scanning module and is used to detect the diameter of the second beam. The second beam detector is located on one side of the displacement stage and is used to detect the diameter of the flat-top spot on the wafer surface. The control module can control the attenuation module to adjust the power of the first beam based on the diameter of the second beam and the diameter of the flat-top spot.

[0014] In some possible implementations, the monitoring module also includes a thermometer and a power meter. The thermometer is located in the optical path extending from the self-expanding module to the scanning module. It is used to collect the infrared beam in the second beam and send the temperature signal characterizing the infrared beam to the control module. The control module can determine the predicted temperature of the reaction region of the wafer based on the temperature signal. The power meter is located on one side of the displacement stage and is used to detect the laser power of the reaction region of the wafer. The control module can control the attenuation module to adjust the power of the first beam based on the predicted temperature and the laser power.

[0015] Secondly, this application also provides a laser annealing method, which includes:

[0016] The first beam is generated by the light source module and transmitted to the beam expander module;

[0017] The diameter of the first beam is adjusted by the beam expander module according to the size of the wafer to emit a second beam, the diameter of which is larger than that of the first beam.

[0018] The shaping module shapes the second beam into a shaped beam, and the uniformity of the shaped beam is not less than a preset uniformity threshold.

[0019] The shaping beam is reflected by a scanning galvanometer and focused by a scanning field lens, and a flat-top spot is irradiated in the first reaction region of the wafer.

[0020] When the first reaction region of the wafer undergoes a siliconization reaction under the action of the light spot, the scanning galvanometer is controlled to deflect at a set angle and a flat-top light spot is irradiated in the second reaction region of the wafer. The first reaction region and the second reaction region are different.

[0021] The aforementioned laser annealing apparatus achieves laser annealing of wafers through the cooperation of a scanning galvanometer and a scanning field mirror. After completing the annealing of one reaction area of ​​the wafer, only the deflection angle of the scanning galvanometer needs to be adjusted to perform annealing on the next reaction area of ​​the wafer, thereby improving the efficiency of laser annealing of wafers. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the laser annealing apparatus in the embodiments of this application;

[0023] Figure 2 This is a schematic diagram of the reaction region in the embodiments of this application;

[0024] Figure 3 This is a schematic diagram of the light spot in the embodiment of this application;

[0025] Figure 4 This is a schematic diagram of the energy distribution of the light spot in the embodiments of this application;

[0026] Figure 5 This is a schematic diagram of the visual detection module in the embodiments of this application;

[0027] Figure 6 This is a schematic diagram illustrating the location of the feature in the embodiments of this application;

[0028] Figure 7 This is a schematic diagram of arc positioning in an embodiment of this application;

[0029] Figure 8 This is a schematic diagram of the laser annealing method in the embodiments of this application. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0031] It should be noted that the terms "first," "second," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. "Multiple" or "several" indicates at least two. The terms "comprising" or "including," and similar terms, mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including," and their equivalents, but do not exclude other elements or objects. The terms "connected" or "linked," and similar terms, are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0032] like Figure 1 and Figure 2 As shown, as one implementation, this application provides a laser annealing apparatus, which includes a displacement stage 11, a light source module 12, a beam expander module 13, a shaping module 14, a scanning module 15, a control module 16, and a vision inspection module 17. The displacement stage 11 supports the wafer. The light source module 12 generates a first beam. The beam expander module 13 is arranged in the optical path formed by the first beam and is used to adjust the diameter of the first beam, expanding it into a second beam, and emitting the second beam, wherein the diameter of the second beam is larger than the diameter of the first beam. The shaping module 14 is arranged in the optical path formed by the second beam and is used to receive the second beam and shape it to form a shaped beam, wherein the uniformity of the shaped beam is not less than a preset uniformity threshold. For example, the uniformity threshold is 95%. The scanning module 15 includes a scanning galvanometer 151 and a scanning field lens 152. The scanning galvanometer 151 reflects the shaping beam to control its scanning path. The scanning field lens 152 focuses the shaping beam reflected by the scanning galvanometer 151 and illuminates a flat-top light spot in the first reaction region 101 of the wafer. The vision inspection module 17 acquires image information of the wafer. The control module 16 is electrically connected to the vision inspection module 17. The control module 16 can determine the second reaction region of the wafer based on the image information. When the first reaction region of the wafer undergoes a siliconization reaction under the action of the light spot, the control module 16 can control the scanning galvanometer 151 to deflect at a set angle and illuminate the flat-top light spot in the second reaction region of the wafer. The positions of the first and second reaction regions are different.

[0033] like Figure 1 As shown, in the implementation of this application, the laser annealing apparatus includes a chamber housing (not shown), which forms a process chamber 103. The displacement stage 11 is always located in the process chamber 103 to confine the wafer within the process chamber 103. The light spot formed by the scanning field lens 152 is also focused in the process chamber 103.

[0034] In some possible implementations, the displacement stage 11 supports at least three degrees of freedom of spatial motion, and the displacement stage 11 can be displaced in three orthogonal directions within the process chamber 103 to adjust the position of the wafer.

[0035] In some possible implementations, the light source module 12 is configured as a laser emitter, which integrates multiple laser sources of different wavelengths, including but not limited to ultraviolet lasers, green lasers, and near-infrared lasers. Depending on different process requirements, the laser emitter can emit lasers of different wavelengths.

[0036] In some possible implementations, the beam expander module 13 is configured as a combination of a converging mirror and a diverging mirror. The converging mirror is used to converge or convert the beam passing through it into a parallel beam, and the diverging mirror is used to diverge or convert the beam passing through it into a parallel beam. The converging mirror and the diverging mirror are arranged alternately to expand the first beam into a second beam, so that the diameter of the second beam meets the diameter required to enter the shaping module 14.

[0037] For example, the beam expanding module 13 includes a first converging mirror 131, a diverging mirror 132 and a second converging mirror 133 arranged in sequence. The first beam passes through the first converging mirror 131, the diverging mirror 132 and the second converging mirror 133 in sequence and is expanded into a second beam, which is then emitted by the second converging mirror 133.

[0038] In some possible implementations, the shaping module 14 is located between the beam expanding module 13 and the scanning module 15. The shaping module 14 includes any one of a microlens array, an aspherical lens combination, an optical diffractive element (DOE), and a spatial light modulator (SLM).

[0039] For example, if the light source module 12 emits a beam quality factor M 2 Larger laser beams have lower beam quality; therefore, shaping module 14, configured as a microlens array, provides better beam homogenization. If the light source module 12 emits a beam quality factor M... 2 Smaller lasers, such as M 2 If the value is ≤1.3, the higher the beam quality, the more likely the shaping module 14 will be configured as an optical diffractometer or a spatial light modulator.

[0040] In some possible implementations, the control module 16 includes an electronic device 161, a main controller 162, and a motion controller 163. The electronic device 161 is capable of calculating and processing data and sending control signals to the main controller 162 and the motion controller 163. The main controller 162 is electrically connected to the light source module 12 and is capable of controlling the light source module 12 to generate a first light beam in response to the control signals. The motion controller 163 is electrically connected to the displacement stage 11 and also electrically connected to the scanning galvanometer 151. The motion controller 163 is capable of controlling the deflection of the scanning galvanometer 151 in response to the control signals.

[0041] For example, when the first reaction region 101 of the wafer undergoes a siliconization reaction and completes the annealing of the wafer surface under the illumination of the light spot focused by the scanning field lens 152, the motion controller 163 controls the scanning galvanometer 151 to deflect at a set angle, so that the light spot focused by the scanning field lens 152 moves to the second reaction region 102 of the wafer, so that the second reaction region 102 of the wafer undergoes a siliconization reaction and completes the annealing of the wafer surface.

[0042] It should be noted that increasing the size of the light spot formed in the reaction region and increasing the scanning speed of the scanning galvanometer 151 can both improve the efficiency of wafer laser annealing. The scanning speed of the scanning galvanometer 151 is the product of the angular velocity of the scanning galvanometer 151 and the focal length of the scanning field lens 152. For a scanning field lens 152 with a scanning area of ​​Φ200, the focal length of the scanning field lens 152 is greater than or equal to 290mm, and the scanning speed of the scanning galvanometer 151 can be greater than or equal to 20m / s. Here, the scanning area refers to the maximum area range that can achieve uniform focused light spot coverage.

[0043] The above settings enable annealing of different reaction regions of the wafer. By controlling the deflection of the scanning galvanometer 151, the position of the light spot on the wafer surface can be changed, which can greatly improve the annealing efficiency of the wafer.

[0044] In some possible implementations, at least a portion of the first reaction region 101 and at least a portion of the second reaction region 102 overlap.

[0045] like Figure 2 and Figure 3 As shown, the first reaction region 101 further includes an annealed region and an unannealed region, and the second reaction region 102 includes an annealed region and an unannealed region. The light spot energy density received by any annealed region is greater than the light spot energy density received by any unannealed region, and the unannealed region of each reaction region surrounds the annealed region of that reaction region. The annealed region in the second reaction region 102 overlaps with the unannealed region in the first reaction region 101.

[0046] It should be noted that, Figure 2 and Figure 3 This is only a schematic diagram of the reaction region; the shape of the reaction region can be circular, rectangular, etc.

[0047] like Figure 4 The diagram shown is a schematic representation of the light spot energy distribution in the implementation of this application. Figure 4 The horizontal axis represents the position coordinates of the light spot, and the vertical axis represents the light spot energy density. In the implementation of this application, the light spot energy density received in the annealed region is greater than or equal to 90%, and the light spot energy density received in the unannealed region is between 13.5% and 90%. It should be noted that insufficient light spot energy density will prevent annealing from being completed.

[0048] It should be noted that the first reaction region 101 and the second reaction region 102 do not represent two specific regions on the wafer, but only two different regions where the two light spots formed by the scanning field lens 152 focus twice consecutively are located. Since the light spots are formed by focusing the shaping beam, the energy density of the light spot received in the annealed region is higher and the distribution is more uniform. The annealed region of the wafer can complete the repair of lattice defects in a single scan. The energy density of the light spot received in the unannealed region is lower and the distribution is uneven. The wafer in the unannealed region cannot complete the repair of lattice defects in a single scan. It is necessary to perform a supplementary scan on the unannealed region of the wafer through overlapping scan, and use the annealed region of the second reaction region 102 to complete the repair of lattice defects in at least part of the unannealed region of the first reaction region 101.

[0049] By setting the above, the annealed area of ​​the second reaction region 102 overlaps with the unannealed area of ​​the first reaction region 101, avoiding the inability to repair lattice defects in some areas of the wafer, ensuring the integrity of the wafer annealing, and avoiding the need to anneal the unannealed area separately, thus improving the efficiency of wafer laser annealing.

[0050] like Figure 1 As shown, in some possible implementations, the laser annealing apparatus also includes an attenuation module 18, which is located in the optical path extending from the light source module 12 to the beam expansion module 13. The attenuation module 18 is used to adjust the power of the first beam, and the control module 16 can control the attenuation module 18 to reduce the power of the first beam based on the preset spot energy density required for processing the wafer.

[0051] In the implementation of this application, the attenuation module 18 includes a half-wave plate 181, a polarization element 182, and a beam collector 183. The half-wave plate 181 is used to adjust the power of the first beam and transmit the first beam to the polarization element 182. The polarization element 182 is used to separate a portion of the beam from the first beam and transmit the separated portion of the beam to the beam collector 183.

[0052] For example, the separated portion of the beam can be vertical light, parallel light, etc.

[0053] In some possible implementations, the attenuation module 18 further includes an attenuation control component (not shown), which is connected to the control module 16. The half-wave plate 181 is also connected to the attenuation control component. The attenuation control component can respond to attenuation control commands from the control module 16 by changing the angle of the half-wave plate 181 relative to the optical axis of the first beam, thereby changing the power of the first beam. If the power of the first beam is reduced, the power of the perpendicular light separated by the polarization element 182 increases; if the power of the first beam is increased, the power of the perpendicular light separated by the polarization element 182 decreases. For example, the attenuation control component may be a motor.

[0054] It should be noted that the power of the first beam generated by the light source module 12 is constant, meaning the total power of the first beam separated by the polarization element 182 and the vertical light is constant. Separating the vertical light from the first beam prevents it from affecting the deflection and positioning of the scanning galvanometer 151, and also prevents the vertical light from forming secondary spots on the wafer, which could lead to a decrease in the annealing effect or even damage to the wafer. Collecting the vertical light through the beam collector 183 prevents it from leaking outside the laser annealing apparatus and prevents it from interfering with the optical paths within the laser annealing apparatus.

[0055] The above settings allow for adjustment of the power of the first beam, thereby improving the annealing effect of the laser annealing device on the wafer.

[0056] like Figure 1 and Figure 5 As shown, in some possible implementations, the visual inspection module 17 includes a displacement component 171 and a camera component 172. The displacement component 171 includes a guide rail 1711 and a connecting unit 1721. The guide rail 1711 is located above the displacement stage 11. The connecting unit 1721 is connected to the guide rail 1711 and can move relative to the guide rail 1711 along the extension direction of the guide rail 1711. The camera component 172 includes a visual camera 1721 and a telecentric lens 1722. The telecentric lens 1722 is connected to the visual camera 1721. The visual camera 1721 is mounted on the connecting unit 1721 and can move relative to the guide rail 1711 under the drive of the connecting unit 1721.

[0057] To clearly illustrate the implementation of this application, the following are also defined: Figure 5The displacement stage 11 is shown in the front-back and left-right directions. In some possible implementations, the displacement assembly 171 includes a pair of parallel guide rails 1711, both of which are located above the displacement stage 11, i.e., the two guide rails 1711 are fixed above the housing forming the process chamber 103. A connecting unit 1712 is connected between the two guide rails 1711 and is movable relative to the guide rails 1711 along the extension direction of the guide rails 1711. The camera assembly 172 includes a vision camera 1721, a telecentric lens 1722, and a vision inspection mirror 1723. The vision inspection mirror 1723 is located in the optical path extending from the telecentric lens 1722 to the wafer. The vision inspection mirror 1723 is capable of reflecting at least a portion of the image of the wafer, so that at least a portion of the image of the wafer enters the telecentric lens 1722 and the vision camera 1721.

[0058] Specifically, both guide rails 1711 extend along the front-back direction of the displacement stage 11. When viewed along the left-right direction of the displacement stage 11, the two guide rails 1711 overlap. The two guide rails 1711 can move synchronously under the drive of the motor, so as to drive the connecting unit 1712 to move relative to the two guide rails 1711.

[0059] The telecentric lens 1722 extends along the left and right direction of the displacement stage 11. The telecentric lens 1722 and the vision camera 1721 are installed in a horizontal configuration. The telecentric lens 1722 is parallel to the side of the displacement stage 11 facing the wafer. The telecentric lens 1722 can magnify at least a portion of the wafer at a constant magnification and present the magnified image of at least a portion of the wafer in the vision camera 1721.

[0060] It should be noted that the vision camera 1721 can be a single imaging camera or multiple imaging cameras. Using a single imaging camera can reduce the cost of the laser annealing device; using multiple imaging cameras can improve the positioning accuracy of the wafer.

[0061] In some embodiments, the camera assembly 172 further includes an illumination unit (not shown) that can generate a light source to illuminate the wafer and improve the accuracy of the image information of the wafer acquired by the vision inspection module 17.

[0062] With the above configuration, the vision inspection mirror 1723 reflects at least a portion of the image of the wafer, and the telecentric lens 1722 and the vision camera 1721 are installed in a horizontal configuration, so that the telecentric lens 1722 is parallel to the side of the displacement stage 11 facing the wafer. This avoids the poor stability of the connection unit 1712 caused by the long telecentric lens 1722, thereby saving space and improving the convenience of installation and debugging of the telecentric lens 1722.

[0063] like Figure 6As shown, in some possible implementations, the laser annealing apparatus has a teaching position, which is a manually marked position. The wafer has a characteristic position; exemplarily, the edge of the wafer is arc-shaped and has a notch, and the junction of the arc-shaped edge and the notch is the characteristic position. Figure 6 The circular area shown. Before laser annealing, the vision camera 1721 can acquire the position information between the feature position and the teaching position of the wafer, and send the position information to the control module 16. The control module 16 can determine the position of the wafer based on the position information and control the displacement stage 11 to move so that the feature position of the wafer coincides with the teaching position.

[0064] like Figure 7 As shown, in some possible implementations, the wafer has an arc-shaped edge with multiple positioning points at the edge. These positioning points are spaced apart and form the characteristic locations of the wafer. Figure 7 The circular area shown. Before laser annealing, the vision camera can acquire the position information between the feature position and the teaching position of the wafer, and send the position information to the control module 16. The control module 16 can determine the position of the wafer based on the position information and control the displacement stage 11 to move so that the feature position of the wafer coincides with the teaching position.

[0065] The above settings enable precise positioning of the wafer, eliminating the need for manual calibration and improving the efficiency of wafer laser annealing.

[0066] like Figure 1 As shown, in some possible implementations, the laser annealing apparatus further includes a monitoring module 19, which is electrically connected to the control module 16. The monitoring module 19 is used to monitor the diameter or power of the second beam and send the monitoring signal characterizing the diameter or power of the second beam to the control module 16. The control module 16 can control the attenuation module 18 to adjust the power of the first beam based on the monitoring signal.

[0067] In some possible implementations, the monitoring module 19 includes a first beam detector 191 and a second beam detector 192. The first beam detector 191 is located in the optical path extending from the self-expanding module 13 to the scanning module 15 and is used to detect the diameter of the second beam. The second beam detector 192 is located on one side of the displacement stage 11 and is used to detect the diameter of the light spot on the wafer surface. The control module 16 can control the attenuation module 18 to adjust the power of the first beam based on the diameter of the second beam and the diameter of the light spot.

[0068] like Figure 1As shown, specifically, the monitoring module 19 also includes a beam detection beam splitter 193, which is located in the optical path extending from the self-beam expander module 13 to the scanning module 15. The beam detection beam splitter 193 separates the diameter detection beam from the second beam, and the diameter detection beam can pass through the beam detection beam splitter 193 and enter the first beam detector 191.

[0069] In some possible implementations, the first beam detector 191 is configured as a beam profiler. The first beam detector 191 is capable of detecting the first beam parameters of the diameter detection beam to determine whether the first beam can enter the shaping module 14. The first beam parameters include the diameter, roundness, and shape of the light spot formed by the beam.

[0070] In some possible implementations, the first beam detector 191 is configured as a photodetector capable of detecting second beam parameters of the diameter detection beam, including the pulse stability and repetition rate of the beam.

[0071] It should be noted that the first beam parameter of the diameter detection beam is the same as the first beam parameter of the second beam; the second beam parameter of the diameter detection beam is the same as the second beam parameter of the second beam. Therefore, detecting the diameter detection beam can obtain the first beam parameter and / or the second beam parameter of the second beam.

[0072] In some possible implementations, the second beam detector 192 is configured as a beam profiler. The second beam detector 192 is capable of receiving a second beam and detecting the shape of the light spot illuminating the wafer surface to obtain light spot parameters, including the diameter, roundness, uniformity, etc. of the light spot.

[0073] like Figure 1 As shown, in some possible implementations, the monitoring module 19 also includes a thermometer 194 and a power meter 195. The thermometer 194 is located in the optical path extending from the self-beam expander module 13 to the scanning module 15, and is used to collect the infrared beam in the second beam and send the temperature signal characterizing the infrared beam to the control module 16. The control module 16 can determine the predicted temperature of the reaction region of the wafer based on the temperature signal. The power meter 195 is located on one side of the displacement stage 11 and is used to detect the laser power of the reaction region of the wafer. The control module 16 can control the attenuation module 18 to adjust the power of the first beam based on the predicted temperature and the laser power.

[0074] In the implementation of this application, the temperature sensor 194 is configured as an infrared temperature measurement camera, and the monitoring module 19 also includes a dichroic mirror 196. Short-wavelength beams, such as ultraviolet beams, can pass through the dichroic mirror 196; long-wavelength beams, such as infrared beams, can be reflected by the dichroic mirror 196. The temperature sensor 194 can collect the infrared beams reflected by the dichroic mirror 196, generate a temperature signal characterizing the infrared beams, and send the temperature signal to the control module 16 to measure and calculate the predicted temperature of the reaction region of the wafer.

[0075] like Figure 1 As shown, in some possible implementations, the monitoring module 19 further includes a power detection reflector 197 and a light source power detector 198. The power detection reflector 197 and the light source power detector 198 are located in the optical path extending from the light source module 12 to the attenuation module 18. The light source power detector 198 is electrically connected to the control module 16. The power detection reflector 197 reflects the first beam, allowing it to enter the light source power detector 198. The light source power detector 198 generates a power detection signal characterizing the power of the first beam and sends this signal to the control module 16. The control module 16 calculates the power of the first beam generated by the light source module 12 based on the power detection signal to monitor the lifespan of the light source module 12.

[0076] It should be noted that the power detection reflector 197 can be reused as an optical shutter. The power detection reflector 197 can be displaced along a direction perpendicular to the first beam generated by the light source module 12 to control the on / off state of the optical path extending from the light source module 12 to the attenuation module 18. If the power detection reflector 197 reflects the first beam, the optical path extending from the light source module 12 to the attenuation module 18 is disconnected; if the power detection reflector 197 does not reflect the first beam, the optical path extending from the light source module 12 to the attenuation module 18 is unobstructed.

[0077] Through the above settings, the status of the first beam, the second beam, and the wafer is monitored, thereby realizing real-time monitoring of the working status of the laser annealing device. The monitoring module 19, together with the attenuation module 18, can also realize closed-loop adjustment of the power of the first beam, reduce manual intervention in the laser annealing device, and thus improve the efficiency of wafer laser annealing processing.

[0078] In some possible implementations, adding a reflector to the optical path of the laser annealing device can fold the optical path, compress its volume, and thus reduce the size of the laser annealing device.

[0079] like Figure 8 As shown, this application also provides a laser annealing method applied to the aforementioned laser annealing apparatus, the laser annealing method comprising:

[0080] S101: Generate a first beam based on the light source module 12 and transmit the first beam to the beam expander module 13.

[0081] Before the light source module 12 generates the first beam, the vision inspection module 17 can detect the position of the wafer to be processed, and the control module 16 can control the displacement stage 11 to move based on the position information generated by the vision inspection module 17, so as to adjust the position of the wafer to the preset position.

[0082] In some embodiments, after the light source module 12 generates the first beam, the power detection reflector 197 can reflect the first beam so that the first beam enters the light source power detector 198. The light source power detector 198 generates a power detection signal characterizing the power of the first beam and sends the power detection signal to the control module 16. The control module 16 calculates the power of the first beam generated by the light source module 12 based on the power detection signal in order to monitor the lifespan of the light source module 12.

[0083] In some embodiments, after the light source module 12 generates the first beam, the first beam can enter the attenuation module 18 to adjust the power of the first beam, and the vertical light separated from the first beam can be recovered by the attenuation module 18.

[0084] S 102: The beam expansion module 13 is controlled to adjust the diameter of the first beam according to the size of the wafer so as to emit a second beam, the diameter of the second beam being larger than the diameter of the first beam.

[0085] It should be noted that the shaping module 14 has certain requirements for the diameter of the beam entering itself. After the beam expanding module 13 expands the first beam into the second beam, the monitoring module 19 can detect whether the second beam meets the requirements of the shaping module 14 for the diameter of the beam entering itself.

[0086] S103: The second beam is shaped into a shaped beam based on the shaping module 14.

[0087] The uniformity of the shaping beam is not less than 95%.

[0088] In some embodiments, the light source module 12 emits laser with a high beam quality factor, and the shaping module 14 is configured as a microlens array.

[0089] In some embodiments, the light source module 12 emits laser light with a low beam quality factor, and the shaping module 14 is configured as an optical diffractometer or a spatial light modulator.

[0090] It should be noted that the second beam is a Gaussian beam before shaping. Compared with the Gaussian beam, the energy distribution of the shaping beam is more uniform and more suitable for repairing lattice defects in the wafer.

[0091] S104: The shaping beam is reflected by the scanning galvanometer 151 and focused by the scanning field lens 152, and a flat-top spot is irradiated in the first reaction region 101 of the wafer.

[0092] In some embodiments, the vision inspection module 17 can observe the reaction area of ​​the wafer to provide real-time feedback on the wafer's processing status.

[0093] In some embodiments, the monitoring module 19 can monitor the temperature of the wafer surface, and the control module 16 can measure and calculate the predicted temperature of the reaction region of the wafer based on the temperature signal generated by the monitoring module 19, and control the attenuation module 13 to adjust the power of the first beam.

[0094] In some embodiments, the monitoring module 19 can monitor the laser power in the reaction region of the wafer, and the control module 16 can adjust the power of the first beam based on the laser power control attenuation module 13.

[0095] It should be noted that annealing different reaction regions of a wafer by deflecting the scanning galvanometer 151 is faster and more accurate than annealing different reaction regions of a wafer by displacement of the stage 11.

[0096] S105: When the first reaction region 101 of the wafer undergoes a siliconization reaction under the action of the light spot, the scanning galvanometer 151 is controlled to deflect at a set angle and a flat-top light spot is irradiated in the second reaction region 102 of the wafer. The first reaction region 101 and the second reaction region 102 are different.

[0097] Whenever a reaction area of ​​the wafer undergoes a siliconization reaction under the action of the light spot, the monitoring module 19 can observe the processing status of the wafer surface and confirm the position that needs to be scanned again, so as to quickly deflect the angle of the scanning galvanometer 151, realize the rapid calibration of the scanning galvanometer 151, ensure that the reaction area of ​​the scanning galvanometer 151 is correct in the next scan, and improve the efficiency of wafer annealing processing.

[0098] It should be noted that although the steps in the above process or the flowchart in the accompanying figure show a logical order, in some cases, the steps shown or described may be performed in a different order than that shown here.

[0099] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A laser annealing apparatus, characterized in that, include: A displacement stage (11) is used to support the wafer; A light source module (12) is used to generate a first beam; A beam expander module (13) is used to adjust the diameter of the first beam to emit a second beam, the diameter of the second beam being larger than the diameter of the first beam. Shaping module (14) is used to receive the second beam and shape the second beam to form a shaped beam, wherein the uniformity of the shaped beam is not less than a preset uniformity threshold. The scanning module (15) includes a scanning galvanometer (151) and a scanning field lens (152). The scanning galvanometer (151) is used to reflect the shaping beam, and the scanning field lens (152) is used to focus the shaping beam emitted through the scanning galvanometer (151) and irradiate a flat-top spot in the first reaction region (101) of the wafer. A visual inspection module (17) is used to acquire image information of the wafer; The control module (16) is electrically connected to the vision detection module (17). When the first reaction area (101) of the wafer undergoes a siliconization reaction under the action of the flat-top light spot, the control module (16) can control the scanning galvanometer (151) to deflect at a set angle and irradiate the flat-top light spot in the second reaction area (102) of the wafer. The positions of the first reaction area (101) and the second reaction area (102) are different. The control module (16) can also determine the unreacted area of ​​the wafer based on the image information and control the scanning galvanometer (151) to deflect and irradiate the flat-top light spot in the unreacted area of ​​the wafer.

2. The laser annealing apparatus according to claim 1, characterized in that, The first reaction region (101) and the second reaction region (102) overlap at least partially.

3. The laser annealing apparatus according to claim 2, characterized in that, Both the first reaction region (101) and the second reaction region (102) include an annealed region and an unannealed region. The spot energy density received by the annealed region is greater than that received by the unannealed region, and the unannealed region surrounds the annealed region. The annealed region in the second reaction region (102) overlaps with the unannealed region in the first reaction region (101).

4. The laser annealing apparatus according to claim 1, characterized in that, The laser annealing device further includes an attenuation module (18), which is located in the optical path extending from the light source module (12) to the beam expansion module (13). The attenuation module (18) is used to adjust the power of the first beam. The control module (16) can control the attenuation module (18) to reduce the power of the first beam based on the preset energy density required to process the wafer.

5. The laser annealing apparatus according to claim 4, characterized in that, The attenuation module (18) includes a half-wave plate (181), a polarizing element (182), and a beam collector (183). The half-wave plate (181) is used to adjust the power of the first beam and transmit it to the polarizing element (182). The polarizing element (182) is capable of separating a portion of the beam from the first beam and transmitting the separated portion of the beam to the beam collector (183).

6. The laser annealing apparatus according to claim 1, characterized in that, The visual inspection module (17) includes a displacement component (171) and a camera component (172). The displacement component (171) includes a guide rail (1711) and a connecting unit (1712). The guide rail (1711) is located above the displacement stage (11). The connecting unit is connected to the guide rail (1711) and can move relative to the guide rail (1711) along the extension direction of the guide rail (1711). The camera component (172) includes a visual camera (1721) and a telecentric lens (1722). The telecentric lens (1722) is connected to the visual camera (1721). The visual camera (1721) is mounted on the connecting unit (1712) and can move relative to the guide rail (1711) under the drive of the connecting unit (1712).

7. The laser annealing apparatus according to claim 4, characterized in that, The laser annealing device further includes a monitoring module (19), which is electrically connected to the control module (16). The monitoring module (19) is used to monitor the diameter or power of the second beam and send the monitoring signal characterizing the diameter or power of the second beam to the control module (16). The control module (16) can control the attenuation module (18) to adjust the power of the first beam based on the monitoring signal.

8. The laser annealing apparatus according to claim 7, characterized in that, The monitoring module (19) includes a first beam detector (191) and a second beam detector (192). The first beam detector (191) is located in the optical path extending from the beam expander module (13) to the scanning module (15) and is used to detect the diameter of the second beam. The second beam detector (192) is located on one side of the displacement stage (11) and is used to detect the diameter of the flat-top spot on the wafer surface. The control module (16) can control the attenuation module (18) to adjust the power of the first beam based on the diameter of the second beam and the diameter of the flat-top spot.

9. The laser annealing apparatus according to claim 7, characterized in that, The monitoring module (19) further includes a thermometer (194) and a power meter (195). The thermometer (194) is located in the optical path extending from the beam expander (13) to the scanning module (15), and is used to collect the infrared beam in the second beam and send the temperature signal characterizing the infrared beam to the control module (16). The control module (16) can determine the predicted temperature of the reaction region of the wafer based on the temperature signal. The power meter (195) is located on one side of the displacement stage (11) and is used to detect the laser power of the reaction region of the wafer. The control module (16) can control the attenuation module (18) to adjust the power of the first beam based on the predicted temperature and the laser power.

10. A laser annealing method, applied to the laser annealing apparatus according to any one of claims 1 to 9, characterized in that, The laser annealing method includes: The first beam is generated by the light source module (12) and transmitted to the beam expander module (13); The beam expanding module (13) adjusts the diameter of the first beam according to the size of the wafer to emit a second beam, the diameter of which is larger than that of the first beam. The second beam is shaped into a shaped beam by the shaping module (14), and the uniformity of the shaped beam is not less than a preset uniformity threshold. The shaping beam is reflected by the scanning galvanometer (151), and the shaping beam emitted by the scanning galvanometer (151) is focused by the scanning field lens (152) and a flat-top light spot is irradiated in the first reaction region (101) of the wafer. When the first reaction region (101) of the wafer undergoes a siliconization reaction under the action of the flat-top light spot, the scanning galvanometer (151) is controlled to deflect at a set angle and the flat-top light spot is irradiated in the second reaction region (102) of the wafer. The first reaction region (101) and the second reaction region (102) are different.

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