Automatic silicon wafer detection mechanism and detection method

Abstract

The application discloses a kind of silicon wafer automatic detection mechanism and detection method, the silicon wafer automatic detection mechanism includes: conveying mechanism, return mechanism, monitoring photographing mechanism, image analysis device, six-axis manipulator and several silicon wafer collecting devices;Conveying mechanism one end is connected with sintering furnace main body machine, the other end is provided with several silicon wafer collecting devices, return mechanism is located conveying mechanism both sides, monitoring photographing mechanism is located conveying mechanism top, for shooting the appearance of silicon wafer;Six-axis manipulator is located conveying mechanism side, for respectively grabbing and placing silicon wafer on conveying mechanism into corresponding silicon wafer collecting device;Image analysis device is electrically connected with detection photographing mechanism, six-axis manipulator respectively.The application adopts full automation production, relies on the detection scheme that infrared short wave camera and photoelectric sensor are combined, not only can avoid visual fatigue and error caused by long time work of artificial detection, can also greatly improve production efficiency, reduce artificial cost.

Description

Technical Field

[0001] This invention relates to a solar photovoltaic sintering equipment, and more particularly to an automatic silicon wafer testing mechanism and testing method. Background Technology

[0002] As a typical representative of equipment in the photovoltaic cell manufacturing industry, the sintering furnace plays an important role in improving the conversion efficiency of silicon wafers in the screen printing process. The sintering furnace sinters the electrodes printed on the silicon wafer into a cell at high temperature, so that the silicon wafer and the electrode itself form an ohmic contact, and the contact of the electrode has a resistive characteristic, so as to achieve the purpose of producing high conversion efficiency cells.

[0003] However, since sintering is a comprehensive process involving diffusion, flow, and physicochemical reactions, under the premise of stable printing conditions, the temperature of the sintering furnace, gas flow rate, and belt speed are the three key factors in sintering. Excessively high or low temperatures in the sintering furnace can cause defects such as wafer warping, aluminum beads, bulging, and grid breakage on the silicon wafers. If these defects are not addressed, and the temperature of the main sintering furnace does not adjust according to the sintering effect, it will cause significant economic losses to the company. Currently, most solar cell manufacturers use manual inspection methods to check each silicon wafer on the sintering conveyor network to eliminate wafers with surface defects and collect defective wafers for replating. However, the human eye cannot continuously and consistently perform these highly repetitive and intelligent tasks. Furthermore, manual inspection has a lag; by the time a problem is discovered and the temperature, flow rate, and belt speed of the sintering furnace are adjusted, a large number of defective wafers have already been produced. In addition, manually adjusting the temperature, flow rate, and belt speed is entirely based on experience, which is time-consuming and greatly affected by the operator's experience. Even experienced operators need to spend nearly 30 minutes to operate the equipment.

[0004] Therefore, the industry urgently needs to develop a device that can quickly, repeatably, and intelligently test and classify silicon wafers.

[0005] Therefore, existing technologies have shortcomings and need to be improved. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an automatic silicon wafer inspection mechanism and inspection method to solve the problem that the human eye cannot continuously, stably and efficiently complete the silicon wafer quality inspection in the prior art, and at the same time solve the data silo problem in the existing solutions.

[0007] To achieve the above objectives, the present invention provides an automatic silicon wafer inspection mechanism, comprising: a conveying mechanism, a settling mechanism, a monitoring and imaging mechanism, an image analysis device, a six-axis robotic arm, and several silicon wafer collection devices; one end of the conveying mechanism is connected to the main body of the sintering furnace, and the other end is provided with the several silicon wafer collection devices; the settling mechanism is located on both sides of the conveying mechanism; the monitoring and imaging mechanism is located above the conveying mechanism and is used to photograph the appearance of the silicon wafers; the six-axis robotic arm is located on one side of the conveying mechanism and is used to grab and place the silicon wafers on the conveying mechanism into the corresponding silicon wafer collection devices; the image analysis device is electrically connected to the monitoring and imaging mechanism and the six-axis robotic arm.

[0008] Furthermore, the straightening mechanism includes: a first processing unit, a silicon wafer detection device, a left straightening unit, and a right straightening unit. The left straightening unit and the right straightening unit each include: a first driving device and an actuator disposed at the output end of the first driving device. The first processing unit is electrically connected to the silicon wafer detection device and the first driving device, respectively.

[0009] Furthermore, the first driving device is a cylinder, the silicon wafer detection device is a pair of photoelectric sensors, each including a transmitter and a receiver. The transmitter is located on the left-side settling unit, the receiver is located on the right-side settling unit, and the actuating element is a long strip plate or guide bar.

[0010] Furthermore, the conveying structure includes two conveyor chains using wire mesh, and the number of straightening mechanisms is two. Each straightening mechanism corresponds to one conveyor chain. The left straightening unit is located on one side of the conveyor chain, and the right straightening unit is located on the other side of the conveyor chain.

[0011] Furthermore, the monitoring and imaging mechanism includes: an installation frame, a positioning sensor assembly mounted on the installation frame, a light source device mounted on the installation frame, and an imaging device mounted on the installation frame, wherein the imaging device is electrically connected to the image analysis device and the positioning sensor assembly respectively.

[0012] Furthermore, the imaging device is an infrared shortwave camera, and there are two of them, with each imaging device corresponding to a transmission chain; there are two positioning sensor assemblies, and each positioning sensor assembly includes four photoelectric sensors for detecting the four sides or four corners of the silicon wafer.

[0013] Furthermore, the monitoring and imaging mechanism also includes a second driving device electrically connected to the image analysis device. The output end of the second driving device is connected to the mounting frame, and the mounting frame can move left and right under the drive of the second driving device.

[0014] The image analysis device is also equipped with a communication interface for connecting to an external network. The image analysis device is connected to a remote server through the communication interface. The image analysis device is a computer.

[0015] The present invention also provides an automatic inspection method for silicon wafers using the above-described automatic inspection mechanism, comprising the following steps:

[0016] Step 1: The sintered silicon wafers are output from the main sintering furnace and transported forward on the conveyor mechanism;

[0017] Step 2: After the straightening mechanism detects the silicon wafer on the conveying mechanism, it straightens it so that the central axis of the silicon wafer is on the same axis as the central axis of the conveying chain.

[0018] Step 3: The monitoring and imaging mechanism takes pictures of the surface of the shaped silicon wafer and sends the picture data to the image analysis device;

[0019] Step 4: The image analysis device compares the received photo with a pre-stored reference photo to obtain the current detection result of the silicon wafer;

[0020] Step 5: The image analysis device controls the six-axis robot arm based on the detection result. The six-axis robot arm picks up the silicon wafers that have been inspected on the conveying mechanism and places them into the corresponding silicon wafer collection device.

[0021] Step 6: The image analysis device uploads real-time production data from the equipment to a remote server via a communication interface.

[0022] Furthermore, in step 2, the same monitoring and imaging device is used to simultaneously photograph the silicon wafers on both transmission chains;

[0023] In step 5, the same six-axis robot is used to grab and place the inspected silicon wafers from the two transport chains into the corresponding silicon wafer collection devices.

[0024] Furthermore, step 6 also includes the image analysis device feeding back the detection results to the operator, who then adjusts the temperature of the sintering furnace body based on the detection results.

[0025] By adopting the above solution, the present invention provides an automatic silicon wafer inspection mechanism and inspection method, which has the following beneficial effects:

[0026] 1. A straightening mechanism is used to straighten the silicon wafers on the conveying mechanism, correcting the skewed silicon wafers and ensuring that the central axis of the silicon wafers is on the same axis as the central axis of the conveying chain, thus ensuring the accuracy of the photos taken at each inspection point for silicon wafer appearance inspection.

[0027] 2. A six-axis robot is used to classify and collect silicon wafers based on the inspection results. This can eliminate silicon wafers with surface defects and collect silicon wafers with surface defects for re-plating. The same robot can operate on two conveyor chains simultaneously, making full use of resources and avoiding waste.

[0028] 3. Fully automated production, requiring no manual intervention; the six-axis robot automatically handles any problems that arise. At the same time, relying on a detection scheme that combines infrared short-wave cameras and photoelectric sensors, it not only avoids visual fatigue and errors caused by long hours of manual inspection, but also greatly improves production efficiency and reduces labor costs.

[0029] 4. It also has a real-time closed-loop data processing function. By using an image analysis device to analyze the captured data, the process can be judged and adjusted in real time based on the collected data. For example, it can realize the heating / cooling control of the sintering furnace, thereby achieving unmanned operation, reducing manual labor and realizing automatic adjustment, improving the yield of silicon wafers, and ensuring the optimization of process effect.

[0030] 5. Send the real-time production data of the equipment to a remote server, organize it into corresponding reports and databases, so that the whole plant's MES system can access it. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the automatic silicon wafer inspection mechanism of the present invention.

[0032] Figure 2 This is a schematic diagram of the structure of the left-side or right-side centering unit in this invention.

[0033] Figure 3 This is a flowchart illustrating the automatic silicon wafer inspection method of the present invention. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0035] This invention adopts the concept of a digital factory, significantly upgrading traditional equipment by introducing robotics and visual inspection technologies, supplemented by big data analytics. This achieves unmanned and intelligent production in this process, truly realizing a "lights-out factory." Specifically, it provides an automatic silicon wafer inspection mechanism that automatically inspects and analyzes the surface of silicon wafers, eliminating those with surface defects. It boasts high stability, short inspection time, and convenient maintenance, avoiding errors caused by prolonged manual labor. It also provides data management for CCD inspection data of sintered silicon wafers and process data during the sintering process. Through real-time analysis and statistics of CCD inspection data, combined with artificial intelligence and big data concepts, it determines the factors leading to abnormal silicon wafers. The big data system then transmits data to the sintering furnace main unit in real-time via Ethernet, enabling real-time adjustments to the furnace temperature, gas flow, and belt speed, thus achieving a fully closed-loop feedback intelligent control of the production line. Please refer to [link to relevant documentation]. Figure 1 The automatic silicon wafer inspection mechanism includes: a conveying mechanism 2, a straightening mechanism 4, a monitoring and imaging mechanism 6, an image analysis device (not shown), a six-axis robot 8, and several silicon wafer collection devices 9. The conveying mechanism 2 is used to convey sintered silicon wafers; one end is connected to the main body of the sintering furnace 10, and the other end is equipped with the several silicon wafer collection devices 9. The straightening mechanism 2 is located on both sides of the conveying mechanism 2 and is used to adjust the position of the silicon wafers on the conveying mechanism 2 to align them with the central axis of the transmission chain 21 of the conveying mechanism 2. The monitoring and imaging mechanism 6 is located above the conveying mechanism 2 and is used to photograph the appearance of the silicon wafers. The six-axis robot 8 is located on one side of the conveying mechanism 2 and is used to pick up and place the silicon wafers on the conveying mechanism 2 into the corresponding silicon wafer collection devices 9. The image analysis device is electrically connected to the monitoring and imaging mechanism 6 and the six-axis robot 8 to receive the image data from the monitoring and imaging mechanism 6 and to control the six-axis robot 8 to complete the corresponding operations. The silicon wafer collection device 9 employs multiple (such as two collection stack wafer boxes 92 and two collection wafer baskets 91) to classify the inspected silicon wafers according to their surface condition.

[0036] More specifically, the conveying structure 2 includes two transmission chains 21 made of wire mesh, and the number of straightening mechanisms 4 is two, with each straightening mechanism 4 corresponding to one transmission chain 21. Each straightening mechanism 4 includes: a first processing unit (not shown), a silicon wafer detection device 43, a left straightening unit 44, and a right straightening unit 42. The left straightening unit 44 is located on one side of the transmission chain 21, and the right straightening unit 42 is located on the other side of the transmission chain 21. Please refer to the relevant documentation. Figure 2The left-side straightening unit 44 and the right-side straightening unit 42 each include a first driving device 51 and an actuator 52 located at the output end of the first driving device 51. The first processing unit is electrically connected to the silicon wafer detection device 43 and the first driving device 51, respectively. When the silicon wafer moves away from the sintering furnace body 10 under the drive of the conveying mechanism 2 and is detected by the silicon wafer detection device 43, the silicon wafer detection device 43 sends a signal to the first processing unit. The first processing unit simultaneously activates the left-side straightening unit 44 and the right-side straightening unit 42. The first driving devices 51 of the left-side straightening unit 44 and the right-side straightening unit 42 push the actuator 52. The actuators 52 of the left-side straightening unit 44 and the right-side straightening unit 42 move from both sides of the transmission chain 21 toward the center of the transmission chain 21 to correct the silicon wafer on the transmission chain 21, so that the central axis of the silicon wafer is on the same axis as the central axis of the transmission chain 21, so as to facilitate subsequent positioning and imaging. In this embodiment, the first driving device 51 is a cylinder, the silicon wafer detection device 43 is a pair of photoelectric sensors, which includes a transmitter 53 and a receiver 54. The transmitter 53 is located on the left-side straightening unit 44, the receiver 54 is located on the right-side straightening unit 42, and the actuating element 52 is a long strip plate or guide bar.

[0037] The monitoring and imaging mechanism 6 includes: a mounting frame, a positioning sensor assembly mounted on the mounting frame, a light source device mounted on the mounting frame, and an imaging device mounted on the mounting frame. The imaging device is electrically connected to the image analysis device and the positioning sensor assembly to obtain the positioning information of the silicon wafers on the transmission chain 21 and to send the image data to the image analysis device. Two infrared shortwave cameras are used as the imaging devices, each corresponding to one transmission chain 21, to simultaneously photograph the silicon wafers on both transmission chains 21. Two positioning sensor assemblies are used, each including four photoelectric sensors for detecting the four sides or four corners of the silicon wafer. The monitoring and imaging mechanism 6 also includes a second driving device electrically connected to the image analysis device. The output of the second driving device is connected to the mounting frame, allowing the mounting frame to move left and right under the drive of the second driving device. The second driving device can be a cylinder or a motor; any device capable of driving the mounting frame to move left and right is acceptable. When the silicon wafer has passed the correction position, it is transported to the imaging station by the transmission chain 21. After the photoelectric sensor used to detect the silicon wafer is detected, it sends a detection command to the image analysis device. The image analysis device controls the second drive mechanism to move the imaging device of the monitoring imaging mechanism above the silicon wafer to take a picture. The photoelectric sensor and the imaging device work together to detect whether there are defects in the silicon wafer.

[0038] The image analysis device is a computer, specifically a host computer controlling the sintering furnace. It includes a second processing unit that retrieves pre-stored reference photos from its internal storage unit, compares them with the photo data from the monitoring and imaging mechanism, and generates monitoring results. Based on these results, it controls the movement of the six-axis robotic arm 8. The image analysis device also has a communication interface for connecting to an external network. Through this interface, it connects to a remote server, allowing production information to be synchronized and monitored remotely in real-time. Specifically, it can simultaneously collect and generate reports and databases for four key data points: energy consumption, production capacity, defect data, and equipment alarm information. The device also has a remote diagnostic interface, enabling remote diagnostic capabilities, allowing for comprehensive monitoring of the equipment's operating status from the workshop office or remote locations.

[0039] For the automatic inspection method of the aforementioned silicon wafer automatic inspection mechanism, please refer to [link / reference needed]. Figures 1-3 This includes the following steps:

[0040] Step 1: The sintered silicon wafers are output from the main sintering furnace 10 and transported forward on the conveying mechanism 2.

[0041] Step 2: After the straightening mechanism 4 detects the silicon wafer on the conveying mechanism 2, it straightens it so that the central axis of the silicon wafer is on the same axis as the central axis of the transmission chain 21.

[0042] The silicon wafer detection device detects the position of the silicon wafer from 43 and sends a signal to the first processing unit. The first processing unit simultaneously activates the left adjustment unit 44 and the right adjustment unit 42 to correct the position of the silicon wafer on the transmission chain 21, so that the central axis of the silicon wafer and the central axis of the transmission chain 21 are on the same axis.

[0043] Step 3: The monitoring and imaging mechanism 6 takes pictures of the surface of the shaped silicon wafer and sends the picture data to the image analysis device.

[0044] By using two imaging devices on the same monitoring and imaging mechanism 6 to simultaneously photograph the silicon wafers on the two transmission chains 21, a high-efficiency working state can be maintained.

[0045] Step 4: The image analysis device compares the received photo with a pre-stored reference photo to obtain the current detection result of the silicon wafer.

[0046] The image analysis device analyzes and processes the signals and images fed back by the imaging device and photoelectric sensor to determine whether there are defects such as continuous or warped wafers, broken gates, aluminum bubbles, or poorly colored wafers on the surface of the silicon wafer.

[0047] Step 5: The image analysis device controls the six-axis robot 8 based on the detection result. The six-axis robot 8 picks up the silicon wafers that have been inspected on the conveying mechanism 2 and places them into the corresponding silicon wafer collection device 9.

[0048] Using the same six-axis robot 8 to pick up and place the inspected silicon wafers from the two transmission chains 21 into the corresponding silicon wafer collection device 9 can save the number of robots and control production costs while ensuring efficiency.

[0049] The silicon wafer collection mechanism 9 classifies the inspected silicon wafers, and the image analysis device processes and analyzes the data. The six-axis robot 8, according to the instructions of the image analysis device, collects the silicon wafers into the corresponding wafer cassettes or baskets. Specifically, the six-axis robot 8 collects silicon wafers with color defects into one silicon wafer collection basket 94, normally sintered silicon wafers into another silicon wafer collection basket 94, connected and warped wafers into one collection stacking wafer cassette 92, and wafers with microcracks, broken gates, or aluminum bubbles into another collection stacking wafer cassette 92.

[0050] Step 6: The image analysis device uploads real-time production data of the equipment to a remote server through the communication interface. The image analysis device also feeds back the detection results to the operators, who then adjust the temperature of the sintering furnace main unit 10 based on the detection results.

[0051] Operators can make judgments on the process based on the collected data, and can control the heating / cooling of the sintering furnace to ensure the optimal process effect.

[0052] This invention features an Industry 4.0 MES interface and a corresponding database, which organizes the data generated by the production line into corresponding reports and databases for access by the entire plant's MES system.

[0053] In summary, the present invention provides an automatic silicon wafer inspection mechanism and method, which has the following beneficial effects:

[0054] 1. A straightening mechanism is used to straighten the silicon wafers on the conveying mechanism, correcting the skewed silicon wafers and ensuring that the central axis of the silicon wafers is on the same axis as the central axis of the conveying chain, thus ensuring the accuracy of the photos taken at each inspection point for silicon wafer appearance inspection.

[0055] 2. A six-axis robot is used to classify and collect silicon wafers based on the inspection results. This can eliminate silicon wafers with surface defects and collect silicon wafers with surface defects for re-plating. The same robot can operate on two conveyor chains simultaneously, making full use of resources and avoiding waste.

[0056] 3. Fully automated production, requiring no manual intervention; the six-axis robot automatically handles any problems that arise. At the same time, relying on a detection scheme that combines infrared short-wave cameras and photoelectric sensors, it not only avoids visual fatigue and errors caused by long hours of manual inspection, but also greatly improves production efficiency and reduces labor costs.

[0057] 4. It also has a real-time closed-loop data processing function. By using an image analysis device to analyze the captured data, the process can be judged and adjusted in real time based on the collected data. For example, it can realize the heating / cooling control of the sintering furnace, thereby achieving unmanned operation, reducing manual labor and realizing automatic adjustment, improving the yield of silicon wafers, and ensuring the optimization of process effect.

[0058] 5. Send the real-time production data of the equipment to a remote server, organize it into corresponding reports and databases, so that the whole plant's MES system can access it.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A silicon wafer automatic detection mechanism, characterized by, The application relates to a silicon wafer sorting device, which comprises a conveying mechanism, a sorting mechanism, a monitoring and photographing mechanism, an image analysis device, a six-axis manipulator and a plurality of silicon wafer collecting devices; one end of the conveying mechanism is connected with a sintering furnace main body machine, the other end of the conveying mechanism is provided with the plurality of silicon wafer collecting devices, the sorting mechanism is arranged on the two sides of the conveying mechanism, the monitoring and photographing mechanism is arranged above the conveying mechanism and used for shooting the appearance of the silicon wafer; the six-axis manipulator is arranged on one side of the conveying mechanism and used for respectively grabbing and placing the silicon wafer on the conveying mechanism into the corresponding silicon wafer collecting device; the image analysis device is electrically connected with the monitoring and photographing mechanism and the six-axis manipulator; the sorting mechanism comprises a first processing unit, a silicon wafer detecting device, a left sorting unit and a right sorting unit; the left sorting unit and the right sorting unit each comprise a first driving device and an execution element arranged at the output end of the first driving device; the first processing unit is electrically connected with the silicon wafer detecting device and the first driving device; the first driving device is a cylinder; the silicon wafer detecting device is a pair of photoelectric sensors which comprise a transmitting end and a receiving end; the transmitting end is arranged on the left sorting unit; the receiving end is arranged on the right sorting unit; and the execution element is a long strip-shaped plate or guide strip; the conveying mechanism comprises two transmission chains adopting iron wire meshes; the number of the sorting mechanisms is 2; each sorting mechanism is arranged corresponding to a transmission chain; the left sorting unit is arranged on one side of the transmission chain; and the right sorting unit is arranged on the other side of the transmission chain; the monitoring and photographing mechanism comprises a mounting frame, a positioning sensor assembly mounted on the mounting frame, a light source device mounted on the mounting frame and a photographing device mounted on the mounting frame; the photographing device is electrically connected with the image analysis device and the positioning sensor assembly; the photographing device is an infrared short-wave camera; the number of the photographing devices is 2; each photographing device is arranged corresponding to a transmission chain; the number of the positioning sensor assemblies is 2; each positioning sensor assembly comprises four photoelectric sensors used for detecting the four edges or four corners of the silicon wafer; the monitoring and photographing mechanism further comprises a second driving device electrically connected with the image analysis device; the output end of the second driving device is connected with the mounting frame; and the mounting frame can move left and right under the driving of the second driving device; the image analysis device is further provided with a communication interface connected with an external network; the image analysis device is connected to a remote server through the communication interface; and the image analysis device is a computer. The application further relates to a silicon wafer sorting method, which comprises the following steps: Step 1: the sintered silicon wafer is output from a sintering furnace main body machine and is transmitted forward on a conveying mechanism; Step 2: after the silicon wafer on the conveying mechanism is detected by a sorting mechanism, the silicon wafer is sorted so that the central axis of the silicon wafer is on the same axis as the central axis of the transmission chain; Step 3: the surface of the sorted silicon wafer is photographed by a monitoring and photographing mechanism, and the photograph data is sent to an image analysis device. ​ ​ ​ 2. The silicon wafer automatic detection mechanism according to claim 1, wherein ​ ​ 3. A method for automatically detecting a silicon wafer using the automatic detection mechanism according to any one of claims 1 to 2, characterized by, ​ ​ ​ ​ Step 4, the image analysis device compares the received photos with the pre-stored reference photos, thereby obtaining the detection result of the current silicon wafer; Step 5, the image analysis device controls the six-axis robot according to the detection result, and the six-axis robot grasps and places the detected silicon wafer on the conveying mechanism into the corresponding silicon wafer collecting device; Step 6, the image analysis device uploads the real-time production data of the equipment to the remote server through the communication interface.

4. The method of claim 3, wherein the step of automatically detecting the silicon wafer comprises the steps of: automatically detecting the silicon wafer by using a camera. In the step 2, the same monitoring and photographing mechanism is used to simultaneously photograph the silicon wafers on the two conveying chains; In the step 5, the same six-axis robot is used to grasp and place the detected silicon wafers on the two conveying chains into the corresponding silicon wafer collecting devices.

5. The method of claim 3, wherein the step of automatically detecting the silicon wafer comprises the steps of: automatically detecting the silicon wafer by using a camera. The step 6 further includes that the image analysis device feeds back the detection result to the operator, and the operator adjusts the temperature of the sintering furnace main body according to the detection result.

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