Method, device and medium for determining components producing epitaxial defects

Abstract

The disclosed embodiments provide a method, device and medium for determining a component that produces an epitaxial defect. The method includes: obtaining the position of a defect of an epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning; detecting the morphology and composition of the defect of the epitaxial wafer to be tested; when it is determined that the position of the defect of the epitaxial wafer to be tested is a contact position with an epitaxial production device, determining the component that produces the defect of the epitaxial wafer to be tested among the components of the epitaxial growth device according to the morphology and composition of the defect of the epitaxial wafer to be tested.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of semiconductor manufacturing technology, and more particularly to a method, device, and medium for determining a component that produces an epitaxial defect. Background Art

[0002] Silicon wafers made of semiconductors are widely used as substrates in the manufacturing process of semiconductor devices. Common ones are polished wafers and epitaxial wafers. Polished wafers are made by slicing single crystal ingots and performing mirror grinding, cleaning and other processes. A single crystal silicon epitaxial layer is formed on the surface of the polished wafer by chemical vapor deposition and other methods to form an epitaxial wafer. Compared with polished wafers, epitaxial wafers have the characteristics of fewer surface defects, excellent crystallinity and controllable resistivity, and are widely used in highly integrated integrated circuit (IC) components and MOS process.

[0003] With the continuous development of semiconductor technology, the quality requirements for silicon wafers are becoming more and more stringent. For epitaxial wafers, epitaxial layer surface defects are the key factors affecting the quality and yield of epitaxial wafers. It is necessary to reduce the epitaxial layer surface defects generated during the epitaxial process and improve the shipment quality and yield of epitaxial wafers. Summary of the invention

[0004] The embodiments of the present disclosure provide a method, device and medium for determining components that produce epitaxial defects; the equipment components that produce defects in epitaxial wafers can be accurately identified, thereby providing guidance for improving the equipment components, reducing the probability of producing epitaxial wafer defects and improving the shipment quality of epitaxial wafers.

[0005] The technical solution of the embodiment of the present disclosure is implemented as follows:

[0006] In a first aspect, an embodiment of the present disclosure provides a method for determining a component that generates an epitaxial defect, the method comprising:

[0007] Obtaining the location of defects of the epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning;

[0008] Detecting the morphology and composition of defects of the epitaxial wafer to be tested;

[0009] When the position of the defect of the epitaxial wafer to be tested is determined to be the contact position with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined in the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested.

[0010] In some examples, detecting the morphology and composition of defects of the epitaxial wafer to be tested includes:

[0011] Obtaining a surface image of the epitaxial wafer to be tested by scanning the surface of the epitaxial wafer to be tested;

[0012] Determining defects of the epitaxial wafer to be tested from the surface image;

[0013] In the surface image, the defect type of the epitaxial wafer to be tested is determined according to the image features of the defect; wherein the image features of the defect correspond to the morphology of the defect;

[0014] When the defect type of the epitaxial wafer to be tested is a stacking fault defect, the elemental composition of the defect of the epitaxial wafer to be tested is obtained.

[0015] In some examples, the step of determining, in components of the epitaxial growth equipment, a component that generates the defect of the epitaxial wafer to be tested according to the morphology and composition of the defect of the epitaxial wafer to be tested includes:

[0016] If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a scratch defect, determining that the component that causes the defect of the epitaxial wafer to be tested is a robot arm used to transfer wafers between chambers of the epitaxial production equipment;

[0017] If the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is oxygen, determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the transfer chamber of the epitaxial production equipment;

[0018] If the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is carbon, determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is a supporting component in the epitaxial production equipment;

[0019] If the impurity elements in the stacking fault defect of the epitaxial wafer to be tested are silicon and chlorine, it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the processing chamber in the epitaxial production equipment.

[0020] In some examples, the method further includes:

[0021] If the impurity element composition in the defect of the epitaxial wafer to be tested is other elements except oxygen, carbon, silicon and chlorine, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0022] In some examples, the method further includes:

[0023] Determining whether the defect of the epitaxial wafer to be tested is within a target detection range according to the position of the defect of the epitaxial wafer to be tested;

[0024] When the defect of the epitaxial wafer to be tested is within the target detection range, it is determined whether contact with the epitaxial production equipment occurs according to the position of the defect of the epitaxial wafer to be tested.

[0025] In some examples, the method further includes:

[0026] When the defect of the epitaxial wafer to be tested is not within the target detection range, or the position of the defect of the epitaxial wafer to be tested is not in contact with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0027] In some examples, the method further includes:

[0028] Using the epitaxial growth equipment to perform an epitaxial process on the polished wafer to obtain a prepared epitaxial wafer;

[0029] Performing defect detection on the prepared epitaxial wafer to determine whether the prepared epitaxial wafer has defects;

[0030] When the prepared epitaxial wafer has defects, cleaning the prepared epitaxial wafer;

[0031] Performing defect detection on the cleaned epitaxial wafer to determine whether the cleaned epitaxial wafer still has defects;

[0032] Among the cleaned epitaxial wafers, the epitaxial wafers still having defects are determined as the epitaxial wafers to be tested.

[0033] In a second aspect, an embodiment of the present disclosure provides a device for determining a component that generates an epitaxial defect, the device comprising: an acquisition unit, a detection unit, and a determination unit; wherein:

[0034] The acquisition unit is configured to acquire the position of a defect of the epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning;

[0035] The detection unit is configured to detect the morphology and composition of defects of the epitaxial wafer to be tested;

[0036] The determination unit is configured to determine the component that causes the defect of the epitaxial wafer to be tested among the components of the epitaxial growth equipment based on the morphology and composition of the defect of the epitaxial wafer to be tested when the position of the defect of the epitaxial wafer to be tested is determined to be the contact position with the epitaxial production equipment.

[0037] In a third aspect, an embodiment of the present disclosure provides a computing device, comprising: a processor and a memory; the processor is used to execute instructions stored in the memory to implement a method for determining a component that produces epitaxial defects as described in the first aspect or any example thereof.

[0038] In a fourth aspect, an embodiment of the present disclosure provides a computer storage medium storing at least one instruction, wherein the at least one instruction is used to be executed by a processor to implement a method for determining a component that produces epitaxial defects as described in the first aspect or any example thereof.

[0039] The disclosed embodiments provide a method, device and medium for determining components that produce epitaxial defects. The components that produce defects in epitaxial production equipment are determined by analyzing the contact between defects in epitaxial wafers that cannot be eliminated by cleaning and components of epitaxial production equipment, and by combining morphology and composition analysis. This provides guidance for providing improvement measures for equipment components, reduces the probability of epitaxial wafer defects, and improves the shipping quality of epitaxial wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic top view of an epitaxial growth apparatus provided for an embodiment of the present disclosure.

[0041] Figure 2 A schematic diagram of the structure of a processing chamber provided in an embodiment of the present disclosure.

[0042] Figure 3 A schematic flow chart of a method for determining a component causing an epitaxial defect provided in an embodiment of the present disclosure.

[0043] Figure 4 A schematic flow chart of a method for determining an epitaxial wafer to be tested provided in an embodiment of the present disclosure.

[0044] Figure 5 A schematic flow chart of another method for determining a component causing epitaxial defects provided in an embodiment of the present disclosure.

[0045] Figure 6 A schematic diagram of a target detection range provided in an embodiment of the present disclosure.

[0046] Figure 7 A schematic diagram of the composition of an apparatus for determining a component causing an epitaxial defect provided in an embodiment of the present disclosure.

[0047] Figure 8 A schematic diagram of another device composition for determining a component causing an epitaxial defect provided in an embodiment of the present disclosure.

[0048] Fig. 9 A schematic diagram of the composition of a computing device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure.

[0050] See also Figure 1 , which shows a schematic top view of an epitaxial growth device 100 applicable to the technical solution of the embodiment of the present disclosure. The epitaxial growth device 100 generally includes: a factory interface (Factory Interface) 102, load lock (Loadlock) chambers 104, 106, a transfer chamber (Transfer chamber) 108, and a process chamber (Process chamber) 120, 122. Figure 1 As shown, wafers in the epitaxial growth apparatus 100 (shown as gray circles in the figure) can be processed in various chambers and transferred between various chambers (shown as solid arrows and dashed arrows in the figure) without being exposed to the surrounding environment outside the epitaxial growth apparatus 100. For example, wafers can be processed in various chambers under low pressure (e.g., less than or equal to about 300 Torr) or vacuum environments or transferred between these various chambers without destroying the low pressure or vacuum environment between various processes performed on these wafers in the epitaxial growth apparatus 100. Figure 1 As shown, the epitaxial growth device 100 has more than one processing chamber, and can perform the epitaxial deposition process of multiple wafers in one batch, thereby improving the production efficiency of epitaxial wafers.

[0051] exist Figure 1 In the example shown, the factory interface 102 includes a docking station 140. The epitaxial growth apparatus 100 also includes a plurality of front opening unit units (FOUPs) 144 adapted to the docking station 140. In some examples, the epitaxial growth apparatus 100 can be operated by a robot ( Figure 1 ), the wafer can be transferred from the front-opening standard cabin 144 to the docking station 140, and then transferred from the docking station 140 to the load lock chambers 104, 106.

[0052] The load lock chambers 104, 106 have respective ports coupled to the factory interface 102 and respective ports coupled to the transfer chamber 108. The transfer chamber 108 further has respective ports coupled to the process chambers 120, 122. In some examples, the ports may be slit openings with slit valves that can be connected to the process chambers 120, 122 by a robot ( Figure 1 (not shown) allows wafers to pass through these ports and is used to provide sealing between corresponding chambers to prevent gas from passing between corresponding chambers. Generally speaking, in order to transfer a wafer through any port, the port is open; otherwise, the port is closed.

[0053] The load lock chambers 104, 106, the transfer chamber 108, and the processing chambers 120, 122 may be fluidly coupled to a gas and pressure control system ( Figure 1 106). The gas and pressure control system may include one or more gas pumps (e.g., a turbo pump, a cryopump, a roughing pump, etc.), a gas source, various valves, and conduits fluidly coupled to various chambers. In operation, a robot of the factory interface 102 transfers a wafer from the FOUP 144 through a port to the load lock chamber 104 or 106. The gas and pressure control system then pumps down the load lock chamber 104 or 106. The gas and pressure control system further maintains the transfer chamber 108 at an internal low pressure or vacuum environment (which may include an inert gas). Thus, the pumping down of the load lock chamber 104 or 106 facilitates the passage of substrates between, for example, the atmospheric environment of the factory interface 102 and the low pressure or vacuum environment of the transfer chamber 108.

[0054] When the wafer is in the already evacuated load lock chamber 104 or 106, the robot transfers the wafer from the load lock chamber 104 or 106 through the port into the transfer chamber 108. The robot can then transfer the wafer to the processing chamber 120, 122 for processing.

[0055] The processing chamber 120 can be any suitable chamber for processing wafers. In some examples, the processing chamber 120 can be used to perform a cleaning process, or to perform an etching process, or to perform a respective epitaxial growth process. In some examples, see Figure 2 , a processing chamber 120 for performing an epitaxial growth process includes: a susceptor 10 and a susceptor support frame 20A. The susceptor 10 is capable of horizontally supporting a wafer W. The susceptor support frame 20A is capable of driving the susceptor 10 to rotate around a central axis X at a certain speed during vapor deposition. During the rotation of the susceptor 10, the wafer W rotates around the central axis X together with the susceptor 10. Specifically, the wafer W remains stationary relative to the susceptor 10, and a small gap G is provided between the radial edge of the susceptor 10 and an adjacent component 10A (e.g., a preheating ring).

[0056] The chamber RC is enclosed by an upper bell jar 30A and a lower bell jar 30B, and the chamber RC accommodates a base 10 and a base support frame 20A. The upper bell jar 30A and the lower bell jar 30B can be made of transparent quartz, for example. The base 10 divides the chamber RC into an upper reaction chamber RC1 and a lower reaction chamber RC2. The wafer W is accommodated in the upper reaction chamber RC1. The gas pressure in the upper reaction chamber RC1 is slightly greater than the gas pressure in the lower reaction chamber RC2 so that the gas in the upper reaction chamber RC1 enters the lower reaction chamber RC2 through the gap G.

[0057] An air inlet 40 and an exhaust port 50 are formed on the left and right sides of the chamber RC, respectively. Specifically, the air inlet 40 is used to transport reaction gases, such as silicon source gas, carrier gas and dopant gas, into the upper reaction chamber RC1. Silicon atoms are generated by the reaction of the silicon source gas and the carrier gas and deposited on the wafer W to form an epitaxial layer on the surface of the wafer W by vapor deposition. The epitaxial layer of the wafer W is doped with a dopant gas to obtain a desired resistivity. For example, chlorosilane-based gases such as trichlorosilane SiHCl3 or dichlorosilane SiH2Cl2 are used as silicon source gases. Hydrogen H2 is used as a carrier gas. Gases with doping elements such as diborane B2H6 or phosphine PH3 are used as dopant gases. The exhaust port 50 is used to discharge the reaction exhaust gas out of the chamber RC.

[0058] In order to grow an epitaxial layer on the wafer W, the reaction gas (silicon source gas and carrier gas) is driven to flow along the upper surface of the wafer W, and the wafer W supported by the susceptor 10 is heated to about 1000° C. to 1200° C. To this end, heat sources providing a high temperature reaction environment are respectively arranged above and below the chamber RC. Figure 1 As shown, the heat source may use a plurality of heating bulbs 60, such as infrared lamps or far infrared lamps. The plurality of heating bulbs 60 are disposed on the periphery of the upper bell jar 30A and the lower bell jar 30B to heat the susceptor 10 and the wafer W by radiant heat from above and below the chamber 2 through the upper bell jar 30A and the lower bell jar 30B.

[0059] exist Figure 2 In the processing chamber 120 shown, a wafer support rod 80A and a wafer support rod carrier 90 arranged directly below the wafer support rod 80A are also provided. Before vapor deposition, the upper bell jar 30A is opened. The wafer W is transferred from the transfer chamber 108 to the wafer support rod 80A by a robot manipulator (not shown in the figure). Then, the wafer support rod 80A is driven down by the descent of the wafer support rod carrier 90, so that the wafer W is loaded into the base 10. Finally, the upper bell jar 30A is closed to complete the process of moving the wafer to the inside of the chamber RC. After completing the process of moving the wafer to the inside of the chamber RC, vapor deposition is performed. After the vapor deposition is completed, the upper bell jar 30A is opened. The wafer support rod 80A is driven up by the rise of the wafer support rod carrier 90 to lift the epitaxial wafer from the base 10. Finally, the epitaxial wafer is moved from the inside of the chamber RC to the transfer chamber 108 by the robot manipulator. In addition, in Figure 2 The illustrated processing chamber 120 further includes a mounting member 70 for assembling various components of the processing chamber 120 .

[0060] In conjunction with the above-mentioned examples of the epitaxial growth device 100 and the processing chamber 120, when performing an epitaxial process, such as a vapor deposition process, and during the transmission process of each chamber of the epitaxial growth device 100, surface defects such as mechanical damage, particle defects, haze defects, scratch defects, etc. are usually formed on the surface of the epitaxial wafer. In addition, during the vapor deposition process, epitaxial stacking faults (ESF, Epitaxy Stacking Fault) and the like are also formed. Among the exemplary defects of the wafer described above, the types of defects that epitaxial wafers usually face include ESF defects, Particle defects, Scratch defects, etc.

[0061] Since the above defects occur during the epitaxial process and the transmission process, the components of the epitaxial growth equipment 100 that come into contact with the wafer during the process and the transmission process are an important cause of the defects of the epitaxial wafer. In order to reduce the number of epitaxial wafer defects and improve the delivery quality of epitaxial wafers, it is necessary to accurately identify the equipment components that cause defects on the epitaxial wafers, thereby providing guidance for improving the equipment components. Based on this, see Figure 3 , which shows a method for determining a component that produces epitaxial defects provided by an embodiment of the present disclosure, the method includes steps S310 to S330.

[0062] In step S310, the position of the defect of the epitaxial wafer to be tested is obtained; wherein the epitaxial wafer to be tested includes the epitaxial wafer to be tested which still has defects after cleaning.

[0063] In the disclosed embodiments, defects on the epitaxial wafer originate from before, during and after the vapor deposition process. For defects generated before the vapor deposition process, if such defects are not promptly processed or eliminated and remain on the wafer, ESF defects will be formed as the epitaxial layer is continuously deposited during the vapor deposition process. For defects generated during the vapor deposition process, ESF defects will also be formed as the epitaxial layer is continuously deposited. For defects generated after the vapor deposition process, they are usually due to scratches that occur during the transmission process, and tiny particles in the air that are adsorbed when the epitaxial layer is formed just after vapor deposition. Among the defects from the above three sources, defects generated after the vapor deposition process can be eliminated through a cleaning process, while ESF defects are more difficult to eliminate through a cleaning process.

[0064] In order to accurately check the equipment components that produce defects on the epitaxial wafer during the epitaxial process and avoid misjudging the defects produced after the vapor deposition process. In some examples, the epitaxial wafers that do not have defects after cleaning can be excluded from the epitaxial wafers to be tested in the embodiments of the present disclosure. Based on this, before step S310 is executed, Figure 4 As shown, the method may further include steps S410 to S450.

[0065] In step S410, an epitaxial growth device is used to perform an epitaxial process on the polished wafer to obtain a prepared epitaxial wafer.

[0066] In step S420, defect detection is performed on the prepared epitaxial wafer to determine whether the prepared epitaxial wafer has defects.

[0067] In step S430 , when the prepared epitaxial wafer has defects, the prepared epitaxial wafer is cleaned.

[0068] In step S440 , defect detection is performed on the cleaned epitaxial wafer to determine whether defects still exist in the cleaned epitaxial wafer.

[0069] In step S450 , among the cleaned epitaxial wafers, an epitaxial wafer that still has defects is determined as an epitaxial wafer to be tested.

[0070] for Figure 4 In the technical solution shown, the defect detection process described in this example can be identified by collecting images of the wafer surface. In detail, a scanning electron microscope (SEM, Scanning Electron Microscope) uses a high-energy electron beam to scan the surface of the epitaxial wafer, and collects secondary electrons generated by the interaction between the high-energy electron beam and the substances on the surface of the epitaxial wafer to obtain a scanned image of the epitaxial wafer. In addition, a scanned image of the epitaxial wafer can also be obtained by a transmission electron microscope and an optical microscope. After obtaining the scanned image of the epitaxial wafer, it can be determined whether there are defects based on the dark spots that appear in the scanned image, and the number of defects of the epitaxial wafer can be determined based on the number of dark spots. If the number of defects of the epitaxial wafer meets the shipping indicators set by the customer, then the technical solution of the embodiment of the present disclosure does not need to be executed for these epitaxial wafers. In other words, when the number of defects of the epitaxial wafer does not meet the shipping indicators, the following will be executed. Figure 3 or Figure 4 The technical solution shown.

[0071] In addition, if it is determined in step S440 that there are no defects in the epitaxial wafer after cleaning, it means that these defects do not originate from the epitaxial process. Then, the process section after the epitaxial process can be used to check for equipment components that produce such defects without executing the solution proposed in the embodiment of the present disclosure to determine the components that produce epitaxial defects.

[0072] In step S320 , the morphology and composition of defects of the epitaxial wafer to be tested are detected.

[0073] In the disclosed embodiment, for defects that cannot be eliminated by cleaning, their morphology and composition can also be detected by SEM. Specifically, the morphology of the defect can be obtained by scanning the image of the epitaxial wafer. The composition of the defect needs to be obtained by collecting the released X-rays after the high-energy electron beam hits the defective area of ​​the wafer and performing energy spectrum analysis. The composition is usually the elemental composition included in the defect.

[0074] In some examples, the step S320 of detecting the morphology and composition of defects of the epitaxial wafer to be tested may include:

[0075] Obtaining a surface image of the epitaxial wafer to be tested by scanning the surface of the epitaxial wafer to be tested;

[0076] Determining defects of the epitaxial wafer to be tested from the surface image;

[0077] In the surface image, the defect type of the epitaxial wafer to be tested is determined according to the image features of the defect, wherein the image features of the defect correspond to the morphology of the defect;

[0078] When the defect type of the epitaxial wafer to be tested is a stacking fault defect, the elemental composition of the defect of the epitaxial wafer to be tested is obtained.

[0079] For the above example, taking the common ESF, Particle and Scratch defects of epitaxial wafers as examples, these three types of defects have typical morphological characteristics. For example, the typical morphology of ESF defects is a pyramid-shaped rectangle, the typical morphology of Particle defects is a circle, and the typical morphology of Scratch defects is a linear scratch. In the surface image of the wafer, these typical morphological features can be reflected by the corresponding image features, so that the defect type that meets the corresponding morphology can be determined based on the image features.

[0080] As for particle defects and slight scratch defects on the surface, since they can be eliminated by the cleaning process, they usually do not appear on the surface of the epitaxial wafer to be tested mentioned in the embodiments of the present disclosure. Based on this, the defect types of the epitaxial wafer to be tested usually include more serious scratch defects and stacking fault defects.

[0081] Scratch defects are usually caused by the transfer in each chamber of the epitaxial production equipment 100. For example, when the robot arm carries the wafer, the wafer is not placed at the center of the tray of the robot arm, so the movement of the wafer during the wafer transfer causes scratches.

[0082] For ESF defects, one possible cause is that defects already exist on the wafer surface before the vapor deposition process, and the defects continuously cover the single crystal epitaxial layer during the vapor deposition process, thus forming a part of the ESF defect. Another possible cause is that during the vapor deposition process, defects appear in the processing chamber 120, and the defects continuously cover the single crystal epitaxial layer during the vapor deposition process, thus forming a part of the ESF defect. For these two possible causes, the components produced are different. Different components are made of different materials. Therefore, in the defects produced by different components, there will be elemental components corresponding to the component materials. In other words, the elemental components in the defects can provide guidance for identifying the components that produce defects.

[0083] In step S330, when the position of the defect of the epitaxial wafer to be tested is determined to be the contact position with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined in the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested.

[0084] In the embodiment of the present disclosure, if the defect position of the epitaxial wafer to be tested corresponds to the contact position of the epitaxial production equipment 100, then it can be preliminarily determined that the defect is caused by one or more components in the epitaxial production equipment 100 that can contact the defect position. However, since the structures, materials and ways of causing defects of different components are different, and a position on the wafer may be contacted by multiple components during the epitaxial process, it is impossible to accurately locate the defective component if only relying on the contact position. Based on this, the embodiment of the present disclosure combines the morphology and composition of the defect detected in step S320 to make a determination, which reduces the probability of misjudgment and accurately identifies the equipment components that cause defects in the epitaxial wafer, thereby providing guidance for providing improvement measures for equipment components, reducing the probability of epitaxial wafer defects and improving the shipment quality of epitaxial wafers.

[0085] exist Figure 3 In the technical solution shown, the defects in the epitaxial wafer that cannot be eliminated by cleaning are analyzed in terms of morphology and composition, and combined with the contact with the components of the epitaxial production equipment, the defective components in the epitaxial production equipment are determined. This provides guidance for improving the equipment components, reduces the probability of epitaxial wafer defects, and improves the quality of epitaxial wafer shipments.

[0086] See also Figure 5 , which shows another method for determining a component that produces epitaxial defects provided by an embodiment of the present disclosure, the method may include steps S510 to S550.

[0087] In step S501, an epitaxial growth device is used to perform an epitaxial process on a polished wafer to obtain a prepared epitaxial wafer.

[0088] In step S502, defect detection is performed on the prepared epitaxial wafer to determine whether the prepared epitaxial wafer has defects.

[0089] In step S503 , when the prepared epitaxial wafer has defects, the prepared epitaxial wafer is cleaned.

[0090] In step S504, defect detection is performed on the cleaned epitaxial wafer to determine whether defects still exist in the cleaned epitaxial wafer.

[0091] In step S505 , among the cleaned epitaxial wafers, the epitaxial wafers still having defects are determined as epitaxial wafers to be tested.

[0092] For the above steps S501 to S505, their detailed description can be found in Figure 4 The description of the scheme shown will not be repeated here.

[0093] In step S506 , the position of the defect of the epitaxial wafer to be tested is obtained.

[0094] In step S507 , a surface image of the epitaxial wafer to be tested is obtained by scanning the surface of the epitaxial wafer to be tested.

[0095] In step S508 , defects of the epitaxial wafer to be tested are determined from the surface image.

[0096] In step S509, in the surface image, the defect type of the epitaxial wafer to be tested is determined according to the image features of the defect. In the embodiment of the present disclosure, the image features of the defect correspond to the morphology of the defect.

[0097] In step S510 , when the defect type of the epitaxial wafer to be tested is a stacking fault defect, the elemental composition of the defect of the epitaxial wafer to be tested is obtained.

[0098] For the above steps S507 to S510, their specific description can refer to the specific description of step S320 in the aforementioned technical solution, and the embodiments of the present disclosure will not be repeated here.

[0099] In step S511 , it is determined whether the defect of the epitaxial wafer to be tested is within a target detection range according to the position of the defect of the epitaxial wafer to be tested.

[0100] In step S512, when the defect of the epitaxial wafer to be tested is within the target detection range, it is determined whether contact with the epitaxial production equipment occurs according to the position of the defect of the epitaxial wafer to be tested.

[0101] In step S513, when the defect of the epitaxial wafer to be tested is not in the target detection range, or the position of the defect of the epitaxial wafer to be tested is not in contact with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0102] For the above steps S511 to S513, specifically, the target detection range may include a range of 100 mm to 150 mm in radius within the epitaxial wafer to be detected, such as Figure 6 The shaded area shown in . During the entire epitaxial process, this range is the range that most frequently contacts the components in the epitaxial production equipment 100. Determining the defective component based on the defects within this range can reduce the computing cost and improve the processing efficiency compared to determining the defective component for the entire wafer. In addition, defects outside the target detection range will hardly come into contact with the components in the epitaxial production equipment 100. Therefore, this part of the defects is not applicable to the technical solution described in the embodiment of the present disclosure, and the cause and component of the defect can be determined by manual re-judgment.

[0103] In addition, within the target detection range, there are still positions where there is no contact with the components. The defects at these positions are also not applicable to the technical solutions described in the embodiments of the present disclosure. The causes and components of the defects can also be determined through manual review.

[0104] For defects in the epitaxial wafer to be tested that are within the target detection range and in contact with the epitaxial production equipment 100 , the component causing the defect can be determined through steps S514 to S517 .

[0105] In step S514, if the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a scratch defect, it is determined that the component causing the defect of the epitaxial wafer to be tested is a robot arm for transferring wafers between chambers of an epitaxial production device.

[0106] In the disclosed embodiment, the scratch defect comes from the scratch caused when the epitaxial wafer contacts the component. In combination with the aforementioned epitaxial process equipment 100, the wafer (including the polished wafer before entering the processing chamber 120 and the epitaxial wafer after the vapor deposition process in the processing chamber 120) is transferred in each chamber by the robot's mechanical arm. For example, after taking the wafer out of one chamber, it is transferred to another chamber and placed on the component for carrying the wafer in the other chamber. If the wafer is not carried in the center of the tray of the mechanical arm, it is easier to scratch the wafer during the process of moving in or out of the chamber.

[0107] In step S515 , if the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is oxygen, it is determined that the component causing the stacking fault defect of the epitaxial wafer to be tested is the transfer chamber of the epitaxial production equipment.

[0108] In the embodiment of the present disclosure, in combination with the aforementioned epitaxial process equipment 100, when the wafer is transferred from the transfer chamber 108 to the processing chamber 120, the robot used for transfer precipitates oxygen under high temperature conditions. After the wafer is deformed due to high temperature, it will come into contact with other parts of the robot in the transfer chamber to produce tiny particles. Oxygen elements exist in the tiny particles. As the vapor deposition process continues, the single crystal silicon epitaxial layer covers the tiny particles, forming an ESF defect in which the impurity element is mainly oxygen. Therefore, when the impurity element composition is mainly oxygen, it can be determined that the component that produces the defect is the transfer chamber.

[0109] In step S516, if the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is carbon, it is determined that the component causing the stacking fault defect of the epitaxial wafer to be tested is a supporting component in the epitaxial production equipment.

[0110] In the disclosed embodiment, in combination with the aforementioned epitaxial process equipment 100, during the process of wafers being transferred in different chambers, they will contact the supporting components that carry the wafers in each chamber, such as the base 10 in the processing chamber 120 and the wafer supporting rod 80A. After the wafer enters the processing chamber 120, it bends and deforms due to the high temperature, causing the edge of the wafer to come into abnormal contact with the supporting components, so that the carbon impurities in these supporting components appear on the surface of the wafer and form ESF defects during the vapor deposition process. According to the causes of the above-mentioned defects, when the impurity element component in the ESF defect of the epitaxial wafer to be tested is mainly carbon, it can be determined that the component that causes the defect is the supporting component.

[0111] In step S517, if the impurity elements in the stacking fault defect of the epitaxial wafer to be tested are silicon and chlorine, it is determined that the component causing the stacking fault defect of the epitaxial wafer to be tested is the processing chamber in the epitaxial production equipment.

[0112] In the embodiment of the present disclosure, in combination with the aforementioned epitaxial process equipment 100, during the vapor deposition process, the silicon source gas, carrier gas and dopant gas, these reaction gases, flow to the processing chamber 120 to react, and the reaction gas decomposes into silicon and is deposited on the wafer and the susceptor 10. In addition, reaction impurity byproducts will be generated, and these byproducts will be discharged from the processing chamber 120. During the wafer transfer process, if the pressure of the processing chamber 120 is greater than the pressure of the transfer chamber 108, due to the pressure difference between the two chambers, the impurity byproducts will flow from the processing chamber 120 exhaust pipe through the processing chamber 120 to the transfer chamber 108. These impurity byproducts will pollute the environment of the processing chamber 120 when entering the processing chamber 120. When the wafer enters the contaminated processing chamber 120 for the vapor deposition process, it will cause more particle defects on the surface of the epitaxial wafer. These particle defects formed by the impurity byproducts will form ESF defects through the vapor deposition process. The main components of this type of defect are silicon Si and chlorine Cl. According to the causes of the above-mentioned defects, when the impurity elements in the ESF defect of the epitaxial wafer to be tested are mainly silicon and chlorine, it can be determined that the component causing the defect is the processing chamber 120 .

[0113] For the above steps S514 to S517, in some examples, they can be used as a specific implementation of step S330 in the aforementioned technical solution.

[0114] In step S518, if the impurity element composition in the defect of the epitaxial wafer to be tested is other elements except oxygen, carbon, silicon and chlorine, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0115] In the disclosed embodiment, the main impurity components in the defect are other elements except oxygen, carbon and silicon, and the cause and components of the defect cannot be directly known by element composition analysis. Therefore, manual re-judgment is also required to determine the cause and components of the defect.

[0116] pass Figure 5 The technical solution shown selects epitaxial wafers to be tested that have defects that cannot be eliminated by cleaning from the epitaxial wafers, and then performs morphology and composition analysis on the defects within the target detection range and in contact with the epitaxial production equipment in the epitaxial wafers to determine the components in the epitaxial production equipment that produce these defects. This provides guidance for improving equipment components, reduces the probability of epitaxial wafer defects, and improves the shipping quality of epitaxial wafers.

[0117] Based on the same inventive concept as the above technical solution, see Figure 7, which shows a device 700 for determining a component that produces an epitaxial defect provided by an embodiment of the present disclosure, the device 700 includes: an acquisition unit 701, a detection unit 702 and a determination unit 703; wherein,

[0118] The acquisition unit 701 is configured to acquire the position of a defect of the epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning;

[0119] The detection unit 702 is configured to detect the morphology and composition of defects of the epitaxial wafer to be tested;

[0120] The determination unit 703 is configured to determine the component that causes the defect of the epitaxial wafer to be tested among the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested when the position of the defect of the epitaxial wafer to be tested is determined to be the contact position with the epitaxial production equipment.

[0121] In some examples, the detection unit 702 is configured to:

[0122] Obtaining a surface image of the epitaxial wafer to be tested by scanning the surface of the epitaxial wafer to be tested;

[0123] Determining defects of the epitaxial wafer to be tested from the surface image;

[0124] In the surface image, the defect type of the epitaxial wafer to be tested is determined according to the image features of the defect; wherein the image features of the defect correspond to the morphology of the defect;

[0125] When the defect type of the epitaxial wafer to be tested is a stacking fault defect, the elemental composition of the defect of the epitaxial wafer to be tested is obtained.

[0126] In some examples, the determining unit 703 is configured to:

[0127] If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a scratch defect, determining that the component that causes the defect of the epitaxial wafer to be tested is a robot arm used to transfer wafers between chambers of the epitaxial production equipment;

[0128] If the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is oxygen, determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the transfer chamber of the epitaxial production equipment;

[0129] If the impurity element component in the stacking fault defect of the epitaxial wafer to be tested is carbon, determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is a supporting component in the epitaxial production equipment;

[0130] If the impurity elements in the stacking fault defect of the epitaxial wafer to be tested are silicon and chlorine, it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the processing chamber in the epitaxial production equipment.

[0131] For some examples, see Figure 8 The device 700 further includes a manual review unit 704, which is configured to:

[0132] If the impurity element composition in the defect of the epitaxial wafer to be tested is other elements except oxygen, carbon, silicon and chlorine, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0133] In some examples, the determining unit 703 is further configured to:

[0134] Determining whether the defect of the epitaxial wafer to be tested is within a target detection range according to the position of the defect of the epitaxial wafer to be tested;

[0135] When the defect of the epitaxial wafer to be tested is within the target detection range, it is determined whether contact with the epitaxial production equipment occurs according to the position of the defect of the epitaxial wafer to be tested.

[0136] In some examples, the manual review unit 704 is further configured to:

[0137] When the defect of the epitaxial wafer to be tested is not within the target detection range, or the position of the defect of the epitaxial wafer to be tested is not in contact with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

[0138] In some examples, the acquisition unit 701 is further configured to:

[0139] Using the epitaxial growth equipment to perform an epitaxial process on the polished wafer to obtain a prepared epitaxial wafer;

[0140] Performing defect detection on the prepared epitaxial wafer to determine whether the prepared epitaxial wafer has defects;

[0141] When the prepared epitaxial wafer has defects, the prepared epitaxial wafer is cleaned; the cleaned epitaxial wafer is defect-detected to determine whether the cleaned epitaxial wafer still has defects;

[0142] Among the cleaned epitaxial wafers, the epitaxial wafers still having defects are determined as the epitaxial wafers to be tested.

[0143] Please refer to Fig. 9, which shows a structural block diagram of a computing device provided by an exemplary embodiment of the present application. In some examples, the computing device 90 may be at least one of a smart phone, a smart watch, a desktop computer, a laptop, a virtual reality terminal, an augmented reality terminal, a wireless terminal, and a laptop portable computer. The computing device 90 has a communication function and can access a wired network or a wireless network. The computing device 90 may generally refer to one of a plurality of terminals, and those skilled in the art may know that the number of the above terminals may be more or less. In some examples, the computing device 90 may receive data based on the wired network or wireless network to which it is connected. It can be understood that the computing device 90 undertakes the calculation and processing work of the technical solution of the present invention, and the embodiments of the present disclosure are not limited to this.

[0144] like Fig. 9 As shown, the computing device in the present application may include one or more of the following components: a processor 910 and a memory 920 .

[0145] Optionally, the processor 910 uses various interfaces and lines to connect various parts of the entire computing device, and executes various functions of the computing device and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 920, and calling data stored in the memory 920. Optionally, the processor 910 can be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), and programmable logic array (PLA). The processor 910 can integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), a neural network processor (NPU), and a baseband chip. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content that needs to be displayed on the touch display; the NPU is used to implement artificial intelligence (AI) functions; and the baseband chip is used to process wireless communications. It is understandable that the above baseband chip may not be integrated into the processor 910, but may be implemented by a separate chip.

[0146] The memory 920 may include a random access memory (RAM) or a read-only memory (ROM). Optionally, the memory 920 includes a non-transitory computer-readable storage medium. The memory 920 may be used to store instructions, programs, codes, code sets, or instruction sets. The memory 920 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above various method embodiments, etc.; the data storage area may store data created according to the use of the computing device, etc.

[0147] In addition, those skilled in the art will appreciate that the structure of the computing device shown in the above figures does not constitute a limitation on the computing device, and the computing device may include more or fewer components than shown, or combine certain components, or arrange the components differently. For example, the computing device also includes a display screen, a camera assembly, a microphone, a speaker, a radio frequency circuit, an input unit, a sensor (such as an acceleration sensor, an angular velocity sensor, a light sensor, etc.), an audio circuit, a WiFi module, a power supply, a Bluetooth module, and other components, which will not be described in detail here.

[0148] An embodiment of the present application further provides a computer-readable storage medium storing at least one instruction, wherein the at least one instruction is used to be executed by a processor to implement the method for determining a component that produces epitaxial defects as described in the above embodiments.

[0149] An embodiment of the present application also provides a computer program product, which includes computer instructions stored in a computer-readable storage medium; a processor of a computing device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computing device executes to implement the method of determining a component that produces epitaxial defects as described in the above-mentioned embodiments.

[0150] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the embodiments of the present application can be implemented with hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein the communication media include any media that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that a general or special-purpose computer can access.

[0151] It should be noted that the technical solutions described in the embodiments of the present disclosure can be combined arbitrarily without conflict.

[0152] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for determining a component that produces epitaxial defects, characterized in that: The method comprises: Obtaining the location of defects of the epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning; Detecting the morphology and composition of defects of the epitaxial wafer to be tested; When it is determined that the position of the defect of the epitaxial wafer to be tested is the contact position with the epitaxial production equipment, the component that generates the defect of the epitaxial wafer to be tested is determined among the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested; in, The method of determining the component that generates the defect of the epitaxial wafer to be tested among the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested comprises: If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a scratch defect, determining that the component that causes the defect of the epitaxial wafer to be tested is a robot arm used to transfer wafers between chambers of the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element component in the stacking fault defect is oxygen, then determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the transfer chamber of the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element component in the stacking fault defect is carbon, then it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is a supporting component in the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested characterizes that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element components in the stacking fault defect are silicon and chlorine, then it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the processing chamber in the epitaxial production equipment.

2. The method according to claim 1, characterized in that: The detecting of the morphology and composition of the defects of the epitaxial wafer to be tested comprises: Obtaining a surface image of the epitaxial wafer to be tested by scanning the surface of the epitaxial wafer to be tested; Determining defects of the epitaxial wafer to be tested from the surface image; In the surface image, the defect type of the epitaxial wafer to be tested is determined according to the image features of the defect; wherein the image features of the defect correspond to the morphology of the defect; When the defect type of the epitaxial wafer to be tested is a stacking fault defect, the elemental composition of the defect of the epitaxial wafer to be tested is obtained.

3. The method according to claim 1, characterized in that: The method further comprises: If the impurity element composition in the defect of the epitaxial wafer to be tested is other elements except oxygen, carbon, silicon and chlorine, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

4. The method according to claim 1, characterized in that: The method further comprises: Determining whether the defect of the epitaxial wafer to be tested is within a target detection range according to the position of the defect of the epitaxial wafer to be tested; When the defect of the epitaxial wafer to be tested is within the target detection range, it is determined whether contact with the epitaxial production equipment occurs according to the position of the defect of the epitaxial wafer to be tested.

5. The method according to claim 4, characterized in that The method further comprises: When the defect of the epitaxial wafer to be tested is not within the target detection range, or the position of the defect of the epitaxial wafer to be tested is not in contact with the epitaxial production equipment, the component causing the defect of the epitaxial wafer to be tested is determined based on the manual judgment result.

6. The method according to claim 1, characterized in that The method further comprises: Using the epitaxial growth equipment to perform an epitaxial process on the polished wafer to obtain a prepared epitaxial wafer; Performing defect detection on the prepared epitaxial wafer to determine whether the prepared epitaxial wafer has defects; When the prepared epitaxial wafer has defects, cleaning the prepared epitaxial wafer; Performing defect detection on the cleaned epitaxial wafer to determine whether the cleaned epitaxial wafer still has defects; Among the cleaned epitaxial wafers, the epitaxial wafers still having defects are determined as the epitaxial wafers to be tested.

7. A device for determining a component that produces an epitaxial defect, characterized in that: The device comprises: an acquisition unit, a detection unit and a determination unit; wherein, The acquisition unit is configured to acquire the position of a defect of the epitaxial wafer to be tested; wherein the epitaxial wafer to be tested includes an epitaxial wafer to be tested that still has defects after cleaning; The detection unit is configured to detect the morphology and composition of defects of the epitaxial wafer to be tested; The determination unit is configured to determine, when determining that the position of the defect of the epitaxial wafer to be tested is the contact position with the epitaxial production equipment, the component that causes the defect of the epitaxial wafer to be tested among the components of the epitaxial growth equipment according to the morphology and composition of the defect of the epitaxial wafer to be tested; Wherein, the determining unit is configured to: If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a scratch defect, determining that the component that causes the defect of the epitaxial wafer to be tested is a robot arm used to transfer wafers between chambers of the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element component in the stacking fault defect is oxygen, then determining that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the transfer chamber of the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested indicates that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element component in the stacking fault defect is carbon, then it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is a supporting component in the epitaxial production equipment; If the morphology of the defect of the epitaxial wafer to be tested characterizes that the defect type of the epitaxial wafer to be tested is a stacking fault defect, and the impurity element components in the stacking fault defect are silicon and chlorine, then it is determined that the component that produces the stacking fault defect of the epitaxial wafer to be tested is the processing chamber in the epitaxial production equipment.

8. A computing device, characterized in that The computing device comprises: a processor and a memory; the processor is used to execute instructions stored in the memory to implement the method for determining a component causing epitaxial defects according to any one of claims 1 to 6.

9. A computer storage medium, characterized in that The storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the method for determining a component causing an epitaxial defect according to any one of claims 1 to 6.

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