Wafer process parameter optimization method and system based on laser scanning

Abstract

The application provides a wafer process parameter optimization method and system based on laser scanning, and relates to the technical field of semiconductors.The method comprises the following steps: determining a first wafer state through millimeter wave scanning; constructing a first gradient transfer relationship and a second gradient transfer relationship, building a light parameter control module and embedding the light parameter control module in a machining machine tool control center; triggering the light parameter control module according to the change of machining requirements, executing a change regulation and control decision based on wafer warping and groove high aspect ratio, executing optimization regulation and control compensation based on wafer state defects according to the first wafer state, determining multi-axis laser parameters, and performing process optimization control on a target wafer.The application solves the technical problem that the machining precision is unstable due to the different wafer warping requirements of different positions, the change of groove geometric state and the existence of flaws on the wafer surface in the wafer machining process in the prior art, and optimizes the precision and yield of wafer machining through the cooperative driving of a laser assembly and a millimeter wave assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, and particularly relates to a wafer process parameter optimization method and system based on laser scanning. BACKGROUND

[0002] In the wafer processing process, wafers at different positions may have different warping requirements, and the geometric state of the trench may also be different due to the change of the processing position and the process, which may increase the processing difficulty. The existing processing process optimization method cannot monitor the wafer state in real time, and lacks adaptive adjustment ability for the change of the processing requirement, so that it is difficult to adjust the processing parameter in time in the processing process, which may cause unstable processing precision, increased error, and further increase the waste rate. When facing complex processing requirements, such as surface defects, micro-cracks or thermal effects of high aspect ratio trenches at different positions, it is difficult to find and correct these defects in time, which may cause quality problems of the processed wafer, and further affect the precision and efficiency of the wafer processing.

[0003] In summary, the prior art has the technical problem that the wafer processing precision is unstable due to the different wafer warping requirements at different positions, the change of the trench geometric state, and the existence of defects or micro-cracks on the wafer surface, which further affects the processing efficiency. SUMMARY

[0004] The purpose of the present application is to provide a wafer process parameter optimization method and system based on laser scanning, which solves the technical problem that the wafer processing precision is unstable due to the different wafer warping requirements at different positions, the change of the trench geometric state, and the existence of defects or micro-cracks on the wafer surface, which further affects the processing efficiency.

[0005] In view of the above problems, the present application provides a wafer process parameter optimization method and system based on laser scanning.

[0006] In a first aspect, the application provides a laser scanning-based wafer process parameter optimization method, which is implemented by a laser scanning-based wafer process parameter optimization system. The laser scanning-based wafer process parameter optimization method comprises: determining a first wafer state by millimeter wave scanning, wherein the first wafer state contains surface features and subsurface features of a first wafer position; constructing a first gradient transfer relationship based on a stress tensor in a wafer warping control dimension, and constructing a second gradient transfer relationship based on thermal accumulation under high aspect ratio trench processing, building a lightweight parameter control module and embedding it in a machining machine tool control; triggering the lightweight parameter control module according to the trend of processing requirements, executing trend regulation and control decisions based on wafer warping and trench high aspect ratio, executing optimization regulation and compensation based on wafer state defects according to the first wafer state, determining multi-axis laser parameters, and performing process optimization control on a target wafer.

[0007] Optionally, the wafer processing mode is a multi-axis self-driving processing mode, and the millimeter wave assembly is arranged at the front end of the laser assembly of each mechanical arm. A wafer processing map is obtained, and multi-mechanical arm processing path driving control is performed in a multi-axis trajectory. The millimeter wave assembly arranged at the front end is used to perform pre-processing trajectory precursor scanning, and the first wafer state is added.

[0008] Optionally, according to the wafer processing map, multi-axis collaborative division is performed to determine a plurality of processing sub-maps. The plurality of processing sub-maps and a device group of multi-mechanical arms are cascaded to assist the lightweight parameter control module to perform process periodic processing control of a target wafer, wherein the plurality of processing sub-maps and the multi-mechanical arms correspond one by one, and the device group contains a millimeter wave assembly and a laser assembly arranged at the front end of the mechanical arm.

[0009] Optionally, a plurality of stress tensors are determined as stress tensor gradients by presetting a plurality of warping states. A first transfer relationship between the stress tensor and the laser parameter is mined according to the wafer warping state. The first transfer relationship is reconstructed according to the stress tensor gradient and a standard state as a reference to determine the first gradient transfer relationship.

[0010] Optionally, a standard state of a target wafer is set as a standard warping level, wherein the standard state is a level of a first warping state under a flawless wafer state. The first transfer relationship is bidirectionally gradient-reconstructed according to the standard warping level as the first gradient transfer relationship.

[0011] Optionally, the target wafer is subjected to laser power-wafer material-thermodynamic correlation mining; a multi-stage trench width-depth ratio is set, and the correlation is subjected to thermal accumulation superposition based on laser power and wafer temperature field to determine a second transfer relationship; a standard trench width-depth ratio is set as a reference, and the second transfer relationship is subjected to bidirectional gradient reconstruction as the second gradient transfer relationship.

[0012] Optionally, according to the first gradient transfer relationship, a first adjustment thread is constructed; according to the second gradient transfer relationship, a second adjustment thread is constructed; the first adjustment thread and the second adjustment thread are parallel to deploy a first control node based on lateral thread interaction fitting; a second optimization node is deployed based on state defect optimization of wafer state; the first control node and the second optimization node are cascaded to determine the lightweight participation control module.

[0013] Optionally, for the processing of the first mechanical arm, a first wafer state of millimeter wave scanning is obtained; the lightweight participation control module embedded in the machining center control is returned to generate a control instruction based on the first difference of the warping state based on control guidance and the second difference based on the trench width-depth ratio, wherein the control instruction is generated when any of the following conditions is met: the warping state requirement exists a difference compared with the standard state, or the trench width-depth ratio requirement exists a difference compared with the standard trench width-depth; according to the control instruction, the first control node is triggered to execute the control decision of the laser parameter to determine the first control parameter.

[0014] Optionally, according to the first wafer state, it is judged whether the surface feature and the subsurface feature exist state defects; if so, the defect feature vector is integrated, the second optimization node is triggered, and the first control parameter is subjected to optimization control based on the defect processing influence according to the defect feature vector to determine the first laser parameter; according to the first laser parameter, the laser assembly of the first mechanical arm is driven to execute laser processing control on the target wafer.

[0015] In a second aspect, the application also provides a wafer process parameter optimization system based on laser scanning, which is used to execute the wafer process parameter optimization method based on laser scanning as described in the first aspect. The wafer process parameter optimization system based on laser scanning comprises: a millimeter wave scanning module, which is used to determine a first wafer state through millimeter wave scanning, wherein the first wafer state contains surface features and subsurface features of a first wafer position; a transfer relationship construction module, which is used to construct a first gradient transfer relationship with a stress tensor under a wafer warping control dimension, to construct a second gradient transfer relationship under thermal accumulation of high aspect ratio trench processing, to build a lightweight parameter control module and to embed the lightweight parameter control module in a machine tool central control; a defect compensation module, which is used to trigger the lightweight parameter control module according to a change in processing requirements, to execute a change regulation and control decision based on wafer warping and trench high aspect ratio, to execute optimization regulation and compensation based on wafer state defects according to the first wafer state, to determine multi-axis laser parameters, and to perform process optimization control on a target wafer.

[0016] The one or more technical solutions provided in the application have at least the following beneficial effects:

[0017] The first wafer state is determined through millimeter wave scanning, wherein the first wafer state contains surface features and subsurface features of a first wafer position; a first gradient transfer relationship is constructed with a stress tensor under a wafer warping control dimension, a second gradient transfer relationship is constructed under thermal accumulation of high aspect ratio trench processing, a lightweight parameter control module is built and embedded in a machine tool central control; a change in processing requirements triggers the lightweight parameter control module, a change regulation and control decision is executed based on wafer warping and trench high aspect ratio, optimization regulation and compensation are executed based on wafer state defects according to the first wafer state, multi-axis laser parameters are determined, and process optimization control is performed on a target wafer. That is, laser assemblies and millimeter wave assemblies are cooperatively driven, the millimeter wave assemblies first scan a previous segment of processing trajectory to determine a specific state, the laser assemblies are controlled after fine tuning when there is a state defect, multi-axis self-driving is performed for complex processing requirements, that is, each device group only focuses on its own part, thereby optimizing the precision and yield of wafer processing and improving production efficiency.

[0018] The above description is only a summary of the technical solutions of the application. In order to enable the technical means of the application to be more clearly understood, the application can be implemented in accordance with the content of the specification, and in order to enable the above and other purposes, features and advantages of the application to be more obvious and easy to understand, the following specific embodiments of the application are described. It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the application, nor is it used to limit the scope of the application. Other features of the application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only exemplary and, for those skilled in the art, other drawings can be obtained without creative effort on the basis of the provided drawings.

[0020] Figure 1 A flowchart of a wafer process parameter optimization method based on laser scanning according to the present application.

[0021] Figure 2 A structural diagram of a wafer process parameter optimization system based on laser scanning according to the present application.

[0022] Legend: millimeter wave scanning module 11, transmission relationship construction module 12, defect compensation module 13. DETAILED DESCRIPTION

[0023] The present application provides a wafer process parameter optimization method and system based on laser scanning, which solves the technical problem in the prior art that the processing precision is unstable due to different wafer warping requirements at different positions in the wafer processing process, changes in groove geometric state requirements, and flaws or micro-cracks on the wafer surface, which further affects the processing efficiency. With the cooperative driving of the laser assembly and the millimeter wave assembly, the millimeter wave assembly first scans the processing track of the previous section to determine the specific state. When there is a state defect, the laser assembly is controlled after fine tuning. For complex processing requirements, multi-axis self-driving is used, that is, each device group only focuses on its own part, thereby optimizing the precision and yield of wafer processing and improving the production efficiency.

[0024] The technical solutions in the application will be described clearly and completely below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. It should be understood that the present application is not limited by the exemplary embodiments described herein. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort fall within the scope of protection of the present application. In addition, it should be noted that, for convenience of description, only parts related to the present application are shown in the drawings, not all.

[0025] Embodiment one, please refer to the accompanying Figure 1 The present application provides a wafer process parameter optimization method based on laser scanning, wherein the wafer process parameter optimization method based on laser scanning is executed by a wafer process parameter optimization system based on laser scanning. The wafer process parameter optimization method based on laser scanning specifically includes the following steps:

[0026] A first wafer state is determined by millimeter wave scanning, wherein the first wafer state contains surface features and subsurface features of the first wafer position.

[0027] Further, the application also includes the following steps: the wafer processing mode is a multi-axis self-driving processing mode, and the millimeter wave assembly is deployed at the front end of the laser assembly of each mechanical arm; a wafer processing map is obtained, and a multi-axis trajectory is used to perform processing path driving control of multiple mechanical arms; and according to the millimeter wave assembly deployed at the front end, a pre-processing trajectory is scanned in advance, and the first wafer state is added.

[0028] Specifically, in the wafer processing process, a multi-axis self-driving processing mode is adopted, in which each mechanical arm is equipped with a millimeter wave assembly and is deployed at the front end of the laser assembly of each mechanical arm to obtain preliminary state data of the wafer before actual processing. Each mechanical arm is responsible for a specific part of the wafer and has the ability to be independently adjusted, so that the wafer can be accurately processed in multiple directions in three-dimensional space. The coordinated work of multiple mechanical arms can avoid the bottleneck problem in the process of a single mechanical arm, and is especially suitable for complex microstructure processing. Millimeter wave is a kind of electromagnetic wave, which is used for scanning, imaging and obtaining state information of wafer surface and subsurface, such as surface defects, warping, stress, etc.

[0029] A wafer processing map is obtained, which is a state information map of the wafer in the entire processing process generated by various sensors, devices and algorithms, containing various parameters of the wafer in different processing stages, such as temperature, stress, thickness change, surface flatness, etc. The wafer processing map reflects the real-time state and change of the wafer in the processing process. Multi-axis trajectory refers to the coordinated work of multiple motion axes in the multi-axis self-driving processing mode, so as to accurately control the processing path, that is, the joint action of multiple axes is used to realize complex processing path planning. The key of multi-axis trajectory is to ensure that the processing path can accurately cover the entire wafer through the coordination of multiple motion axes and mechanical arms. In the multi-axis self-driving processing mode, each axis or mechanical arm undertakes a specific task to perform complex cutting, etching and other operations on the wafer in three-dimensional space. Multiple mechanical arms perform processing path driving control according to the wafer processing map and the multi-axis trajectory, that is, the wafer processing map and the multi-axis trajectory are combined and sent to multiple mechanical arms to adjust their paths and actions. Each mechanical arm independently runs according to the assigned task and dynamically adjusts according to real-time data. For example, if the wafer at a certain position has warping or defects, the path and processing parameters of the mechanical arm are adjusted to avoid further defects in the region.

[0030] Before laser processing, the millimeter wave assembly performs a pre-scan of the wafer surface to detect surface features and potential problems such as micro-cracks, warping, etc. in advance. The pre-scan of the pre-processing trajectory is performed by the millimeter wave assembly deployed at the front end, i.e., the state information of the wafer surface and subsurface is obtained before the actual processing starts. Millimeter wave scanning has high precision and deep penetration capability, which can scan the wafer surface and subsurface, including surface roughness, warping, micro-cracks, etc. in the superficial layer, and even penetrate into the wafer to obtain data such as stress distribution and material inhomogeneity in the subsurface. The pre-scan of the pre-processing trajectory will scan along the laser processing path to identify potential defects and inhomogeneity in advance. For example, the scan may find that the wafer has a warping of 20 µm in some areas or has micro-cracks on the surface.

[0031] The first wafer state includes the surface features and subsurface features obtained by scanning. Surface features include surface flatness, roughness, defects (such as cracks, holes, etc.), while subsurface features involve hidden defects inside the wafer, which need to be indirectly observed by penetration detection technology, such as subsurface cracks, uneven stress distribution, voids / micro-holes, etc. The current state of the wafer can be clearly understood. For example, if the scan results show that the stress distribution in some areas is uneven or there are potential cracks, adjust the laser power or processing path to avoid unnecessary damage to the area. For example, use a four-axis processing system, where each axis has a movement range of ±100 mm (total travel 200 mm), a scan frequency of 50-100 Hz, and a millimeter wave scanning accuracy of 1 µm. The diameter of the wafer is 200 mm and the thickness is 725 µm. After millimeter wave scanning, it is found that the wafer warps to 20 µm at a certain position and has slight micro-cracks on the surface. According to the scan results, adjust the power and path of the laser to avoid excessive processing of this area. The power adjustment of the laser processing process is 3-8 W, the crack area is reduced to 3 W (to avoid thermal stress), the non-defect area remains at 8 W (fine-tuned from the standard 10 W), and the scan accuracy is adjusted to 0.5 µm to ensure that the defect does not further expand.

[0032] Through real-time millimeter wave scanning and laser path adjustment, the information of the wafer surface and subsurface can be accurately obtained to ensure precision adjustment during processing. The millimeter wave assembly first scans the processing trajectory of the previous section to determine the specific state of the wafer. Millimeter wave is the key tool for capturing surface and subsurface features due to its balance between penetration depth and resolution. When performing surface feature detection, millimeter wave scanning uses reflected wave amplitude mutation to identify scratches / particles (sensitivity: height difference > 10 nm), and when performing subsurface feature detection, millimeter wave scanning analyzes internal defects through phase delay and multiple scattering.

[0033] A first gradient transfer relationship is constructed based on the stress tensor in the wafer warping control dimension, a second gradient transfer relationship is constructed based on the thermal accumulation in the high aspect ratio trench processing, a lightweight parameter control module is built and embedded in the machine tool control.

[0034] Further, the application further includes the following steps: determining a plurality of stress tensors as stress tensor gradients by presetting a plurality of wafer warping states; excavating a first transfer relationship between the stress tensor and the laser parameters based on the wafer warping state; and reconstructing the first transfer relationship based on the standard state as a reference according to the stress tensor gradients to determine the first gradient transfer relationship.

[0035] Further, the application further includes the following steps: setting a standard state of a target wafer as a standard warping level, wherein the standard state is a level of a wafer in a first warping state without defects; and bidirectionally gradientizing and reconstructing the first transfer relationship based on the standard warping level as the first gradient transfer relationship.

[0036] Specifically, the wafer may warp due to uneven stress during processing, and the multi-level warping state refers to dividing the wafer warping degree into different levels, such as slight warping, moderate warping, and severe warping, for describing the local or overall deformation of the wafer surface. According to the multi-level warping state, a plurality of stress tensors are determined as stress tensor gradients, that is, for each warping level, the stress data of the wafer at each position is collected, for example, the stress tensor corresponding to the slight warping state (5µm) is (13MPa, 12MPa, 0.5MPa); the stress tensor corresponding to the moderate warping state (10µm) is (25MPa, 24MPa, 1.0MPa); and the stress tensor corresponding to the severe warping state (more than 20µm) is (50MPa, 48MPa, 2.0MPa). The stress tensor gradient is the change trend or difference of the stress tensor at different positions or different warping states of the wafer. Through the stress tensor gradient, the change of the stress with the position, time, or warping level can be analyzed.

[0037] According to the wafer warping state, a first transfer relationship between the stress tensor and the laser parameters (such as power, scanning speed, etc.) is established. By comparing the processing results under different warping states, the adjustment relationship between the warping degree and the laser parameters is obtained. For example, for the area with warping less than 10µm, the laser power can be kept at 10W and the scanning speed is set to 1.1mm / s; for the area with warping more than 10µm, the laser power needs to be reduced by 15% and the scanning speed needs to be slowed down by 5%, so that the energy density E decreases by about 11% (the energy density is determined by the power P and the speed v), to avoid excessive thermal accumulation and further warping.

[0038] The first transfer relationship refers to the mathematical relationship between the wafer warping state and the laser processing parameters. During the processing, the degree of wafer warping directly affects the processing effect, and the laser power, focal position, scanning speed and other parameters need to be adjusted according to the warping state. By analyzing the relationship between the warping state and the laser parameters, a corresponding mathematical model or mapping relationship is constructed, which is the first transfer relationship.

[0039] The standard state of the target wafer is set, i.e. the ideal state of the target wafer, to define the target and reference for processing control. In wafer processing, the standard state usually refers to the ideal state of the wafer without defects or warping. The standard warping level is the standard level of the defined wafer warping state, i.e. in the ideal state of the wafer without defects, a warping level (usually the first warping state) is set as the reference benchmark. The first warping state is the preliminary warping state that may occur during the processing of the wafer. According to the set standard state, the wafer warping level is defined. The standard warping level is usually the warping level of the wafer under ideal processing conditions. For example, if the standard state warping is set to 10 µm, if the actual wafer warping exceeds 10 µm, it indicates that the warping level is high and needs to be adjusted.

[0040] According to the standard warping level, the first transfer relationship is reconstructed in two directions with gradient, and the control parameters are adjusted when the warping is increased or decreased, respectively, to ensure accurate processing control at each level. The two dimensions are consistent, and the reference state is the main control state of the current target wafer processing, such as the stress tensor state with the largest position ratio and the trench ratio state with the largest position ratio. The trench ratio usually refers to the ratio of the depth to the width of the trench during processing. The two-way reconstruction, i.e. on the basis of the previous progressive relationship, takes the reference state as the benchmark, and performs multi-level reconstruction at each level from the increasing direction (increasing warping or trench depth) and the decreasing direction (decreasing warping or trench depth), so that subsequent control is based on the reference as the main line, and according to the level difference between the real-time state and the reference state, the decision of the adjustment state is made quickly. That is, during actual processing, the state of the wafer is monitored in real time and compared with the reference state. If the difference between the real-time state and the reference state is large, the processing parameters are quickly adjusted according to the difference. For example, if the warping at a certain position is detected to increase during scanning, the laser power is reduced and the scanning speed is slowed down; if the warping decreases, the laser power and the scanning speed may be increased.

[0041] Based on the bidirectional gradient reconstruction, the first gradient transfer relationship is obtained, that is, under different warping states, how to adjust the laser parameters according to the stress tensor and the warping state. According to the difference between the wafer warping state and the standard warping level, the laser power and the scanning speed are automatically adjusted. With the increase of warping degree, the laser power is gradually reduced and the scanning speed is slowed down to ensure that the warping will not be further deteriorated. By presetting multiple levels of warping states and establishing the first transfer relationship between the stress tensor and the laser parameters, the laser parameters are quickly adjusted according to the actual warping state of the wafer through bidirectional gradient reconstruction, so as to realize more accurate machining control.

[0042] Further, the present application further comprises the following steps: performing laser power-wafer material-thermodynamics-based concomitant relationship mining on the target wafer; setting a multi-level trench width-depth ratio, performing thermal accumulation superposition on the concomitant relationship based on laser power and wafer temperature field, and determining a second transfer relationship; setting a standard trench width-depth ratio as a reference, and performing bidirectional gradient reconstruction on the second transfer relationship as the second gradient transfer relationship.

[0043] Specifically, in the wafer processing process, the laser power-wafer material-thermodynamics-based concomitant relationship mining is performed on the target wafer, and the relationship between the laser power, the wafer material characteristics (such as thermal conductivity, specific heat, thermal expansion coefficient, etc.) and the thermal effect generated in the processing process is mined. For example, under certain specific laser power, the thermal diffusion behavior of the material can cause local area temperature rise, which may affect the formation of wafer warping, cracking and other defects. In the processing process, the higher the laser power, the more significant the thermal effect, and the more uneven the distribution of the temperature field. The heat applied by the laser in the processing process is closely related to the thermodynamic characteristics of the wafer material such as thermal conductivity, thermal diffusivity, specific heat, etc. The change of laser power directly affects the temperature field of the wafer, thereby affecting the processing effect of the wafer (such as warping, cracking, material removal rate, etc.).

[0044] The multi-level trench width-depth ratio is set, which refers to the ratio of the depth to the width of the etched trench in the semiconductor manufacturing process. The multi-level trench width-depth ratio means that different trench depth and width ratios are used in different processing processes, which is usually used to describe the etching characteristics under different process conditions. Higher depth-width ratio (such as deep trench) will bring greater thermal effect and stress concentration, so special attention should be paid to temperature control and thermal accumulation. For example, for deep trench etching, the width-depth ratio may be 2:1, and for shallow trench etching, the width-depth ratio may be 1:1.

[0045] During the machining process, the effect of the laser beam on the wafer not only produces a thermal effect at a single irradiation, but also gradually accumulates over multiple irradiations. In order to accurately analyze the temperature field changes of the wafer, the thermal effect needs to be accumulated and superimposed. For example, after two consecutive laser machining processes, the local temperature may rise from the initial 25°C to 40°C. By superimposing all the thermal effects, the overall temperature field distribution of the wafer during the entire machining process can be obtained. By calculating the effect of thermal accumulation, the temperature field of the wafer under different machining conditions can be determined, so as to predict the occurrence of problems such as warping and cracking.

[0046] According to the laser power and the thermal accumulation effect, a second transfer relationship is established, which refers to how to adjust the temperature field according to different laser powers to ensure that the wafer remains stable during the machining process. For example, when the laser power is increased, the scanning speed, laser focal point position or power need to be adjusted accordingly to avoid local overheating. Through the second transfer relationship, it is calculated how to adjust the laser power to control the temperature field under different groove width-depth ratios. For example, deeper grooves may require lower laser power to reduce thermal accumulation.

[0047] A standard trench width-depth ratio (e.g., 1:1) is set as a reference benchmark to establish an ideal processing temperature field and laser power relationship. Based on the standard trench width-depth ratio, the laser power and the corresponding temperature field are increased or decreased. For example, if the trench width-depth ratio is increased (deep trench), the laser power needs to be reduced; if the trench width-depth ratio is reduced, the laser power can be appropriately increased to accommodate less heat accumulation. During the adjustment process of the increase and decrease, the laser power is quickly judged and adjusted based on real-time data to ensure that the temperature field during processing is always within the optimal range. Based on the bidirectional gradient reconstruction, a second gradient transfer relationship is constructed, i.e., how to adjust the laser power and scanning speed under different laser power, trench width-depth ratio and temperature field conditions to optimize the wafer temperature control and processing effect. For example, assuming that the wafer size is 200 mm and the thickness is 725 µm, and the laser power used for processing is 10 W. Set the standard trench width-depth ratio to 1:1, and the laser power is the standard value. During the experiment, the temperature field distribution of the wafer is measured. During processing, when the trench width-depth ratio is 2:1, the local temperature field increases by 15°C. Based on the second transfer relationship, the laser power is automatically reduced by 5% according to the requirement of increasing the trench depth, and the laser power is adjusted from 10 W to 8 W, and the scanning speed is reduced by 5%. When the trench width-depth ratio is 1:1, the laser power is maintained at 10 W, and the scanning speed is 1 mm / s, and the processing precision is maintained within the ideal range. The deep trench (width-depth ratio 2:1) in the processing after the laser power is reduced, the local temperature rise is reduced, the warping phenomenon is reduced, and the yield rate is increased by 12%. The temperature field of the standard trench (width-depth ratio 1:1) is stable, the processing precision is maintained within the design requirement, and the yield rate is stable. According to different laser power, trench width-depth ratio and temperature field, the laser parameters are accurately adjusted to avoid warping or defects caused by overheating. By adjusting the laser power and scanning speed in real time, the temperature field can be maintained within a controllable range to ensure the accuracy during processing.

[0048] Further, the application further comprises the following steps: constructing a first adjustment thread according to the first gradient transfer relationship; constructing a second adjustment thread according to the second gradient transfer relationship; parallelizing the first adjustment thread and the second adjustment thread to deploy a first control node based on lateral thread interaction fitting; deploying a second optimization node based on state defect optimization of the wafer state; cascading the first control node and the second optimization node to determine the lightweight control module.

[0049] Specifically, the first gradient transfer relationship is the relationship between wafer warping state (such as warping amplitude) and laser processing parameters (such as laser power, scanning speed, etc.). By analyzing the stress tensor under different warping states, the first gradient transfer relationship between warping and stress is established. The second gradient transfer relationship is the interaction between laser power and wafer temperature field, which indicates how to adjust the laser power to control the wafer temperature field, thereby avoiding problems caused by heat accumulation (such as warping, cracking, etc.). By analyzing the thermal effects in high aspect ratio trench processing, the second gradient transfer relationship, i.e. the relationship between laser power and wafer temperature field, is established.

[0050] Based on the first gradient transfer relationship, the first adjustment thread is constructed, which is responsible for adjusting the laser parameters (such as power, scanning speed, etc.) according to the change of warping state. The task of the first adjustment thread is to monitor the change of warping in real time and dynamically adjust the laser parameters to optimize wafer processing. Based on the second gradient transfer relationship, the second adjustment thread is constructed, which is responsible for adjusting the laser parameters according to the change of temperature field. The second adjustment thread monitors the change of wafer temperature field and adjusts the laser power or other parameters when needed to control the temperature distribution and avoid overheating problems.

[0051] The first and second adjustment threads will run in parallel and coordinate through lateral thread interaction fitting, that is, their adjustment measures are mutually coordinated when adjusting the warping state and temperature field. For example, when the first adjustment thread adjusts the laser power to deal with warping problems, the second adjustment thread may further adjust the power according to the change of temperature field to avoid overheating. This parallel adjustment can ensure that the two important factors (warping and temperature) are optimized at the same time, ensuring the processing precision and wafer quality.

[0052] The first control node is responsible for dynamic adjustment based on the warping state. By monitoring the warping change of the wafer, the first control node will adjust the laser power and scanning speed according to the first gradient transfer relationship to optimize the warping control in the processing process. For example, if the warping degree exceeds the set threshold, the node will adjust the laser power to reduce heat accumulation and avoid further aggravation of warping.

[0053] According to the state defect optimization of wafer state, the second optimization node is constructed to reduce the influence of defect area and improve the final processing quality through wafer state defect optimization. The second optimization node focuses on the state defect optimization of the wafer, monitors the actual processing state of the wafer, including surface flaws, cracks, etc., and makes optimization adjustment through real-time feedback of the processing process. If defects (such as cracks) are detected in a certain area of the wafer, the second optimization node will make adjustments to reduce the expansion of defects and improve the stability and yield of processing.

[0054] By cascading the first regulation node and the second optimization node, a lightweight parameter control module is formed to adjust parameters in real time according to the state changes of the wafer during the processing. The first regulation node and the second optimization node work in parallel and interact to ensure that key factors such as warping and temperature during processing are fully optimized. The lightweight parameter control module ultimately adjusts parameters such as laser power and scanning speed based on real-time data and standard parameters, thereby optimizing processing quality and improving yield. By combining warping control and thermal control, the lightweight parameter control module can quickly respond to changes in wafer state during processing and optimize processing precision.

[0055] The lightweight parameter control module is embedded in the central control system of the machine tool to control and optimize the processing in real time. Embedded deployment means that the lightweight parameter control module will be integrated into the central control system of the processing machine tool to adjust the processing conditions based on feedback data, i.e., comparing the feedback data of the scanned warping state and groove width-depth ratio with the standard state to determine whether parameter adjustment is needed, and automatically executing the adjustment based on the first gradient transfer relationship and the second gradient transfer relationship. For example, assume that the wafer size is 200 mm and the thickness is 725 µm, and the target warping degree is 20 µm. The groove width-depth ratio is set to 2:1, and the initial laser power is set to 10 W. At the beginning of the experiment, the warping degree of the wafer is 10 µm. Based on the first gradient transfer relationship, the laser power is adjusted to 9 W based on the stress tensor data to avoid an increase in warping degree. During processing, the local temperature of the wafer rises to 38°C. According to the second gradient transfer relationship, excessive temperature may cause thermal accumulation problems, so the laser power is automatically reduced to 8 W, and the scanning speed is slowed down to control the temperature field. Through the first gradient transfer relationship and the second gradient transfer relationship, the laser power and scanning speed are adjusted in real time to avoid the effects of warping and overheating, ensuring processing precision.

[0056] As the processing requirements change, the lightweight parameter control module is triggered to execute trend regulation decisions based on wafer warping and groove aspect ratio, perform optimization regulation compensation based on wafer state defects according to the first wafer state, determine multi-axis laser parameters, and control process optimization for the target wafer.

[0057] Further, the present application further includes the following steps: for the processing of the first mechanical arm, obtaining the first wafer state scanned by millimeter waves; returning to the lightweight parameter control module embedded in the central control of the processing machine tool to generate regulation instructions based on the first difference of the warping state controlled by the guide and the second difference based on the groove width-depth ratio, wherein the regulation instructions are generated when any of the following conditions is met: the warping state requirement has a difference compared to the standard state, or the groove width-depth ratio requirement has a difference compared to the standard groove width-depth; and triggering the first regulation node to execute the regulation decision of the laser parameters based on the regulation instructions to determine the first regulation parameters.

[0058] Further, the application further comprises the following steps: judging whether surface features and subsurface features exist state defects according to the first wafer state; if so, integrating defect feature vectors, triggering the second optimization node, and optimizing the first control parameter based on defect processing influence according to the defect feature vectors to determine the first laser parameter; and driving the laser assembly of the first mechanical arm to perform laser processing control on the target wafer according to the first laser parameter.

[0059] Specifically, in wafer processing, the mechanical arm is responsible for accurately performing processing tasks, and millimeter wave scanning is used to obtain real-time state information of the wafer. For the first mechanical arm, the first wafer state of the first wafer position it is responsible for is obtained, including the surface features and subsurface features of the first wafer position. The first wafer state is fed back to the lightweight control module embedded in the machining center control, which is responsible for real-time processing of scanning data and generating corresponding control instructions according to processing needs. The scanning warping state and the trench width-depth ratio are compared with the standard state to determine whether parameter adjustment is needed.

[0060] The lightweight control module analyzes the scanning data, first compares the difference between the warping state of the current wafer and the standard warping state (i.e., the first difference). For example, if the warping degree exceeds the standard state (e.g., the standard warping is 10 pm, while the current warping is 15 pm), an adjustment instruction is generated to reduce the laser power or slow down the scanning speed to avoid further exacerbation of warping. Then, the difference between the trench width-depth ratio of the current wafer and the standard width-depth ratio is compared (i.e., the second difference). For example, the standard width-depth ratio may be 1:1, while the trench width-depth ratio in some areas during actual processing is 2:1, which may cause different thermal effects and processing problems, and the laser parameters are adjusted accordingly.

[0061] When any one of the warping state requirement or the trench aspect ratio requirement exists with the standard state, the corresponding control instruction is generated. That is, if any one meets the difference requirement, that is, the warping state or the trench aspect ratio is different from the standard state, the control instruction is generated. The control instruction includes adjusting the laser power, scanning speed or focus position and other processing parameters. According to the generated control instruction, the first control node is triggered, which is responsible for executing the control decision of the laser parameter. The first control node is responsible for executing the adjustment decision of the laser parameter according to the control instruction. The first control node runs two gradient transfer relationships in parallel: based on the relationship between the wafer warping state and the laser parameter, the laser power, scanning speed, etc. that need to be adjusted are determined; based on the thermal accumulation effect in high aspect ratio trench processing, the laser power, scanning path, etc. that need to be adjusted are determined to reduce thermal accumulation and avoid processing defects. Through the processing of the first control node, the first control parameter, that is, the specific laser adjustment parameter such as power, scanning speed, etc. is determined, which is adjusted through the first control node to optimize the processing quality. The laser assembly of the first mechanical arm executes the laser processing task according to the determined first control parameter. The mechanical arm controls the laser power, focus position and scanning path accurately to ensure that the warping and trench state of the wafer meet the processing standard. For example, assuming that the scanning result shows that the warping degree of a certain area of the wafer is 12µm and the trench aspect ratio is 2:1, which exceeds the standard state. The first difference is determined by comparing the difference between the current wafer warping state (12µm) and the standard warping state (such as 10µm) to determine whether the processing parameter needs to be adjusted; the second difference is determined by comparing the difference between the current wafer trench aspect ratio (2:1) and the standard trench aspect ratio (such as 1:1) to determine whether the processing parameter needs to be further adjusted. Due to the large warping degree, the laser power needs to be reduced to 9W, and the scanning speed can be appropriately slowed down to 0.9mm / s to reduce thermal accumulation. Due to the large trench aspect ratio, the laser power is further reduced to 8W, and the scanning speed is slowed down to 0.9mm / s to avoid excessive thermal accumulation.

[0062] For other positions of the wafer, the above steps are repeated to obtain the wafer state of each position and dynamically adjust according to the difference in warping state and trench aspect ratio. The mechanical arm of each position determines the corresponding laser parameter according to the real-time data to ensure the processing quality of the entire wafer.

[0063] According to the first wafer state of the first wafer position obtained by the millimeter wave scan, it is determined whether the surface features and subsurface features of the wafer have defects, i.e., whether the wafer surface or subsurface has defects that do not meet the standard requirements, such as surface defects (such as stains, scratches, particles, etc.), micro-cracks, scratches, and pits. Defects such as defects belong to state defects, which will affect the processing accuracy and quality of the wafer. If there are defects, integrate the defect feature vector, which contains information such as defect type, location, size, and impact degree. The defect feature vector is a vector that describes the wafer defect, which contains the type (surface defect, crack, scratch, pit, etc.), location, size, depth, and impact degree of the defect. By analyzing the wafer state defect, detailed information about the defect is provided.

[0064] According to the defect trigger second optimization node, the defect feature vector is transmitted to the second optimization node, and the task of the second optimization node is to adjust the laser processing parameters to reduce the impact of defects on the processing process and the final wafer quality. According to the defect feature vector, the parameters such as laser power, scanning speed, and focus are adjusted for optimization. For example, for surface defects, reduce laser power, etc. to eliminate defects, or avoid defect expansion.

[0065] Under the guidance of the second optimization node, the first laser parameter after optimization is calculated based on the impact of the defect. The first laser parameter is the optimized laser parameter according to the defect feature vector, which accurately controls the laser processing process, thereby optimizing the wafer processing quality. The laser assembly of the first mechanical arm performs precise laser processing according to the first laser parameter after optimization. For example, the wafer size is 200mm, the thickness is 725µm, the target warping is 15µm, the initial laser power is 10W, and the scanning speed is 1mm / s. The scanning result shows that the wafer warping is 20µm, the surface has micro-cracks, and some areas have serious surface scratches. The laser power is reduced from 10W to 3W, the scanning speed is adjusted to 0.7mm / s, and the focus position is also fine-tuned to avoid crack expansion caused by heat accumulation. When the warping increases, the curvature of the wafer surface increases, which may cause the focusing point of the laser beam on the wafer surface to change. In order to maintain the processing accuracy, it is necessary to appropriately increase the laser power to ensure that the laser beam can effectively act on the wafer surface to overcome the focus offset caused by warping. The increase in warping may affect the scanning path of the laser beam on the wafer surface. If the scanning speed is too fast, the laser beam may not be able to fully act on the curved surface, resulting in uneven processing or omission. Therefore, in the case of increased warping, the scanning speed needs to be appropriately reduced to ensure that the laser beam can fully cover the wafer surface to achieve uniform processing.

[0066] The same detection, optimization and regulation process is performed for other positions of the wafer. Different types of defects may exist in the wafer of each position, and therefore the laser parameters of each position are independently adjusted according to real-time feedback. By monitoring and adjusting the laser parameters in real time, the influence of warping and defects can be accurately controlled, defect expansion can be avoided, and the processing quality can be ensured.

[0067] Further, the application further includes the following steps: according to the wafer processing map, performing multi-axis collaborative division to determine a plurality of processing sub-maps; cascading the plurality of processing sub-maps and a multi-robot arm device group to assist the lightweight participation control module to perform process periodic processing control of the target wafer, wherein the plurality of processing sub-maps correspond one-to-one to the multi-robot arm device group, and the device group includes a millimeter wave component and a laser component configured at the front end of the robot arm.

[0068] Specifically, the wafer processing map is a detailed plan for each step in the entire processing process, including different regions of the wafer, processing tasks and process parameters. According to the processing map, multi-axis collaborative division is performed to allocate the processing tasks of the wafer to multiple robot arms. Each robot arm is responsible for different regions or tasks, but all robot arms work in coordination to ensure the smooth progress of the entire processing process. The plurality of processing sub-maps are maps that divide the wafer processing map into several sub-regions, each sub-map corresponds to a specific processing task. Each sub-map contains information such as laser processing conditions, scanning path, power setting, etc. for the region. Each sub-map will be assigned to one or more robot arms to ensure accurate control of each region during processing.

[0069] The plurality of processing sub-maps correspond one-to-one to the multi-robot arm device group. Each sub-map will be executed by a specific robot arm device group, and the device group includes a millimeter wave component and a laser component configured at the front end of the robot arm. The millimeter wave component first scans the previous segment of the processing track to determine the specific state, and when there is a state defect, the laser component is controlled after fine tuning. Through multi-axis self-driving, i.e. each device group only focuses on its own part, the processing efficiency is improved.

[0070] The light-weight control module monitors the processing state of the wafer by analyzing data from the millimeter wave assembly in real time, generates corresponding processing instructions according to the processing sub-pattern of different regions, and adjusts the laser parameters (such as power, focal point, scanning speed, etc.) of each mechanical arm in real time. The task of the light-weight control module is to ensure that each mechanical arm can perform its task as needed during the entire wafer processing process, while avoiding the expansion of problems such as warping and defects. Multi-axis self-driving means that each mechanical arm performs tasks in independent axes, reducing the dependence and interference between devices and improving overall processing efficiency. Each mechanical arm focuses on its own part, and through coordinated work, it can process multiple regions at the same time, thereby improving the overall efficiency of wafer processing. Through multi-axis self-driving, conflicts between mechanical arms are effectively avoided, and the advantages of each device are fully utilized to maximize production efficiency.

[0071] In summary, the laser scanning-based wafer process parameter optimization method provided by the present application has the following beneficial effects:

[0072] By millimeter wave scanning, a first wafer state is determined, wherein the first wafer state includes surface features and subsurface features of a first wafer position; a first gradient transfer relationship is constructed based on a stress tensor under wafer warping control dimension, a second gradient transfer relationship is constructed based on thermal accumulation under high aspect ratio trench processing, a light-weight control module is built and embedded in a machining center control; as the processing demand changes, the light-weight control module is triggered to execute wafer warping and trench high aspect ratio change regulation and control decisions, based on the first wafer state, optimization regulation and control compensation based on wafer state defects is executed, multi-axis laser parameters are determined, and process optimization control is performed on the target wafer. That is, the laser assembly and the millimeter wave assembly are cooperatively driven, the millimeter wave assembly first scans the previous processing trajectory to determine the specific state, and when there is a state defect, the laser assembly is controlled after fine tuning. For complex processing requirements, through multi-axis self-driving, each device group only focuses on its own part, thereby optimizing the precision and yield of wafer processing and improving production efficiency.

[0073] Embodiment two, based on the same inventive concept as the laser scanning-based wafer process parameter optimization method in the aforementioned embodiment one, the present application also provides a laser scanning-based wafer process parameter optimization system, please refer to the attached Figure 2 , the laser scanning-based wafer process parameter optimization system comprises:

[0074] The millimeter wave scanning module 11 is configured to determine a first wafer state by millimeter wave scanning, wherein the first wafer state contains surface features and subsurface features of a first wafer position; the transfer relationship construction module 12 is configured to construct a first gradient transfer relationship with a stress tensor in a wafer warping control dimension, to construct a second gradient transfer relationship with thermal accumulation under high aspect ratio trench processing, to build a lightweight parameter control module and to embed the lightweight parameter control module in a machine tool central control; the defect compensation module 13 is configured to trigger the lightweight parameter control module according to the trend of processing requirements, to execute trend regulation and control decisions based on wafer warping and trench high aspect ratio, to execute optimization regulation and compensation based on wafer state defects according to the first wafer state, to determine multi-axis laser parameters, and to perform process optimization control on a target wafer.

[0075] Further, the millimeter wave scanning module 11 in the laser scanning based wafer process parameter optimization system is further configured to: the wafer processing mode is a multi-axis self-driving processing mode, and the millimeter wave assembly is arranged at the front end of the laser assembly of each mechanical arm; a wafer processing map is obtained, and a processing path driving control of multiple mechanical arms is performed in a multi-axis track; a pre-processing track is scanned in advance according to the millimeter wave assembly arranged at the front end, and the first wafer state is added.

[0076] Further, the millimeter wave scanning module 11 in the laser scanning based wafer process parameter optimization system is further configured to: according to the wafer processing map, multiple processing sub-maps are determined by multi-axis collaborative division; the multiple processing sub-maps and a device group of multiple mechanical arms are cascaded to assist the lightweight parameter control module to perform process periodic processing control on a target wafer, wherein the multiple processing sub-maps and the multiple mechanical arms correspond to each other, and the device group contains a millimeter wave assembly and a laser assembly arranged at the front end of the mechanical arm.

[0077] Further, the transfer relationship construction module 12 in the laser scanning based wafer process parameter optimization system is further configured to: determine multiple groups of stress tensors as stress tensor gradients through a plurality of preset multi-level warping states; mine a first transfer relationship between the stress tensor and the laser parameter according to the wafer warping state; and reconstruct the first transfer relationship according to the stress tensor gradient and a standard state as a reference to determine the first gradient transfer relationship.

[0078] Further, the transfer relationship construction module 12 in the laser scanning based wafer process parameter optimization system is further configured to: set a standard state of a target wafer as a standard warping level, wherein the standard state is a level in a first warping state under a flawless wafer state; and perform bidirectional gradient reconstruction on the first transfer relationship according to the standard warping level as the first gradient transfer relationship.

[0079] Further, the transfer relationship construction module 12 in the laser scanning based wafer process parameter optimization system is further used for: performing laser power-wafer material-thermodynamic based concomitant relationship mining on a target wafer; setting a multi-stage trench width-depth ratio, performing laser power and wafer temperature field based thermal accumulation superposition on the concomitant relationship, and determining a second transfer relationship; setting a standard trench width-depth ratio as a reference, performing bidirectional gradientization reconstruction on the second transfer relationship, as the second gradient transfer relationship.

[0080] Further, the transfer relationship construction module 12 in the laser scanning based wafer process parameter optimization system is further used for: constructing a first adjustment thread according to the first gradient transfer relationship; constructing a second adjustment thread according to the second gradient transfer relationship; parallelizing the first adjustment thread and the second adjustment thread to deploy a first regulation node based on lateral thread interaction fitting; deploying a second optimization node based on wafer state based state defect optimization; cascading the first regulation node and the second optimization node to determine the lightweight parameter control module.

[0081] Further, the defect compensation module 13 in the laser scanning based wafer process parameter optimization system is further used for: acquiring a first wafer state of millimeter wave scanning for processing of a first mechanical arm; returning to a lightweight parameter control module embedded in a machining tool bed central control to perform first difference based on control oriented warping state, to perform second difference based on trench width-depth ratio, to generate regulation instructions, wherein the regulation instructions are generated when any of the following conditions is met: the warping state requirement has a difference compared with a standard state, or the trench width-depth ratio requirement has a difference compared with a standard trench width-depth ratio; triggering a first regulation node according to the regulation instructions to perform laser parameter regulation decision, to determine a first regulation parameter.

[0082] Further, the defect compensation module 13 in the laser scanning based wafer process parameter optimization system is further used for: determining whether surface features and subsurface features have state defects according to the first wafer state; if so, integrating defect feature vectors, triggering the second optimization node, and performing optimization regulation of the first regulation parameter based on defect processing influence according to the defect feature vectors, to determine a first laser parameter; driving a laser assembly of the first mechanical arm according to the first laser parameter, to perform laser processing control on a target wafer.

[0083] Each of the embodiments in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The foregoing Figure 1The laser scanning based wafer process parameter optimization method and specific examples in Embodiment One are also applicable to the laser scanning based wafer process parameter optimization system of the present embodiment. Through the foregoing detailed description of the laser scanning based wafer process parameter optimization method, those skilled in the art can clearly understand the laser scanning based wafer process parameter optimization system of the present embodiment. Therefore, for the sake of brevity of the description, no further detailed description is given herein.

[0084] The above description of disclosed embodiments enables one skilled in the art to make or use the application. Numerous modifications to these embodiments will be apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Therefore, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0085] Obviously, for those skilled in the art, several improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the present application.

Claims

1. A method for wafer process parameter optimization based on laser scanning, characterized in that, The method comprises the following steps: Determine the first wafer state by millimeter wave scanning, wherein the first wafer state contains the surface features and subsurface features of the first wafer position; Construct a first gradient transfer relationship based on the stress tensor under the wafer warping control dimension, construct a second gradient transfer relationship based on the heat accumulation under the high aspect ratio trench processing, build a lightweight parameter control module and embed it in the machine tool control; According to the trend of processing requirements, trigger the lightweight parameter control module, execute the trend regulation and control decision based on the wafer warping and trench high aspect ratio, execute the optimization regulation and control compensation based on the wafer state defects according to the first wafer state, determine the multi-axis laser parameters, and perform process optimization control on the target wafer.

2. The laser scanning based wafer process parameter optimization method of claim 1, wherein, The wafer processing mode adopts a multi-axis self-driving processing mode, and the millimeter wave assembly is arranged at the front end of the laser assembly of each mechanical arm; Obtain the wafer processing map, and execute the processing path driving control of the multi-mechanical arm based on the multi-axis track; According to the front-end deployed millimeter wave assembly, the first wafer state is added to the pre-processing track.

3. The laser scanning based wafer process parameter optimization method of claim 1, wherein, Construct a first gradient transfer relationship based on the stress tensor under the wafer warping control dimension, which comprises: Determine a plurality of stress tensors as stress tensor gradients by presetting a plurality of wafer warping states; According to the wafer warping state, the first transfer relationship between the stress tensor and the laser parameter is excavated; According to the stress tensor gradient, the first transfer relationship is reconstructed with the standard state as a reference to determine the first gradient transfer relationship.

4. The laser scanning based wafer process parameter optimization method of claim 3, wherein, According to the stress tensor gradient, the first transfer relationship is reconstructed with the standard state as a reference, which comprises: Set the standard state of the target wafer as the standard warping level, wherein the standard state is the level of the wafer state without defects under the first warping state; According to the standard warping level, the first transfer relationship is bidirectional gradient reconstruction as the first gradient transfer relationship.

5. The laser scanning based wafer process parameter optimization method of claim 1, wherein, Construct a second gradient transfer relationship based on the heat accumulation under the high aspect ratio trench processing, which comprises: Excavate the accompanying relationship based on laser power-wafer material-thermodynamics for the target wafer; Set a plurality of trench width-depth ratios, superimpose the heat accumulation based on the laser power and the wafer temperature field on the accompanying relationship, and determine the second transfer relationship; Set the standard trench width-depth ratio as a reference, and bidirectional gradient reconstruction is performed on the second transfer relationship as the second gradient transfer relationship.

6. The laser scanning based wafer process parameter optimization method of claim 1, wherein, Build a lightweight parameter control module, which comprises: According to the first gradient transfer relationship, construct a first adjustment thread; According to the second gradient transfer relationship, construct a second adjustment thread; Parallel the first adjustment thread and the second adjustment thread to deploy a first regulation and control node based on lateral thread interaction fitting; Deploy a second optimization node based on the state defect optimization of the wafer state; Cascade the first regulation and control node and the second optimization node to determine the lightweight parameter control module.

7. The laser scanning based wafer process parameter optimization method of claim 6, wherein, According to the trend of processing requirements, trigger the lightweight parameter control module to execute the trend regulation and control decision based on the wafer warping and trench high aspect ratio, which comprises: For the processing of the first mechanical arm, obtain the first wafer state by millimeter wave scanning; The light control module embedded in the machining center control is returned to generate a control instruction by performing a first difference based on a control-oriented warping state and a second difference based on a groove width-depth ratio. The control instruction is generated when either of the following conditions is met: a difference exists between the warping state requirement and the standard state, or a difference exists between the groove width-depth ratio requirement and the standard groove width-depth ratio. According to the control instruction, a first control node is triggered to execute a control decision of the laser parameter and determine a first control parameter.

8. The laser scanning based wafer process parameter optimization method of claim 7, wherein, According to the first wafer state, an optimized control compensation based on wafer state defects is performed, including: According to the first wafer state, it is determined whether the surface features and subsurface features have state defects. If there are, the defect feature vector is integrated, the second optimization node is triggered, and the first control parameter is optimized and controlled based on the defect processing influence according to the defect feature vector to determine the first laser parameter. According to the first laser parameter, the laser assembly of the first mechanical arm is driven to perform laser processing control on the target wafer.

9. The laser scanning based wafer process parameter optimization method of claim 2, wherein, According to the wafer processing map, multi-axis collaborative division is performed to determine a plurality of processing sub-maps. The plurality of processing sub-maps and a device group of a plurality of mechanical arms are cascaded to assist the light control module to perform process periodic processing control of the target wafer. The plurality of processing sub-maps and the plurality of mechanical arms correspond one-to-one, and the device group includes a millimeter wave assembly and a laser assembly configured at the front end of the mechanical arm.

10. A laser scanning based wafer process parameter optimization system, characterized in that, The system for implementing the steps of the wafer process parameter optimization method based on laser scanning according to any one of claims 1-9 includes: A millimeter wave scanning module for determining a first wafer state by millimeter wave scanning, wherein the first wafer state includes surface features and subsurface features of the first wafer position. A transfer relationship construction module for constructing a first gradient transfer relationship based on stress tensor under wafer warping control dimension, and constructing a second gradient transfer relationship based on thermal accumulation under high aspect ratio trench processing, and building a light control module and embedding it in the machining center control. A defect compensation module for triggering the light control module to execute a trend control decision based on wafer warping and groove high aspect ratio as the processing requirement changes, and performing optimized control compensation based on wafer state defects according to the first wafer state to determine multi-axis laser parameters and perform process optimization control on the target wafer.

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