Rapid screening method and system for ultrasonic imaging quartz wafers

Abstract

The invention provides an ultrasonic imaging quartz wafer rapid screening method and system, and relates to the technical field of quartz wafer quality inspection, and the method comprises the steps: determining the maximum scanning depth of an ultrasonic scanning microscope, and determining the number of first quartz wafer groups according to the maximum scanning depth and the thickness and yield of a to-be-detected quartz wafer, dividing all the quartz wafers to be detected into a plurality of quartz wafer groups according to the number of the first quartz wafer groups; placing the quartz wafers on a scanning table, and then performing penetration scanning on the quartz wafers in groups by adopting an ultrasonic scanning microscope to obtain corresponding scanning images; defect scanning images which do not meet requirements are screened out from all the scanning images, then the quartz wafers in the quartz wafer sets corresponding to all the defect scanning images are regrouped, and then scanning and screening are conducted again till only one quartz wafer is contained in each defect scanning image to serve as a defect quartz wafer. The method has the beneficial effects that the range of the wafers with defects is gradually reduced until the single wafer is accurately removed, and accurate removal is realized.

Description

Technical Field

[0001] This invention relates to the field of quartz wafer quality inspection technology, and in particular to a rapid screening method and system for quartz wafers using ultrasonic imaging. Background Technology

[0002] Quartz crystal resonators enjoy an extremely high reputation due to their excellent quality factor and unparalleled frequency stability. This stability makes them indispensable for synchronization pulses and time / frequency references in electronic products. With the rapid development of the electronics and information industry and the continuous advancement of technology, the market demand for quartz crystal components has exploded. At the same time, the performance requirements for them are becoming increasingly stringent, especially in terms of frequency stability, miniaturization, and other special specifications.

[0003] Quartz wafers, as a key semi-finished product before quartz crystal packaging, directly affect the performance of the final product. Therefore, accurate testing of the electrical parameters of quartz wafers before packaging is crucial. However, these electrical parameters are often subtly affected by various defects in the wafer's appearance or internal structure. During the quartz wafer manufacturing process, processes such as cutting and grinding inevitably introduce various defects to some extent. These defects not only affect the frequency stability of the quartz wafer but can also severely impact the precision of the final manufactured components.

[0004] Therefore, rigorous screening of the produced quartz wafers to remove those with defects is a crucial step in ensuring product quality. However, in existing technologies, commonly used inspection methods such as dark-field inspection, bright-field inspection, electron beam inspection, and machine vision inspection, while effective in identifying external defects in quartz wafers, fall short in detecting internal defects.

[0005] To address this challenge, we need to continuously explore new testing technologies and methods to achieve accurate identification and assessment of internal defects in quartz crystal wafers. This will help us further improve the performance and reliability of quartz crystal components, meeting increasingly stringent market demands. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a rapid screening method for quartz crystals using ultrasound imaging, comprising:

[0007] Step S1: The host computer determines the maximum scanning depth of the ultrasonic scanning microscope, and then determines the number of the first quartz wafer group as the first grouping method based on the maximum scanning depth, the thickness of the quartz wafer to be tested, and the yield rate.

[0008] Step S2: The operator divides all the quartz crystals to be tested into multiple first quartz crystal groups according to the first grouping method and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each first quartz crystal group to obtain the corresponding scanning image.

[0009] In step S3, the host computer filters out defective scan images that do not meet the requirements from each of the scan images. Then, the operator regroups all the quartz wafers corresponding to all the defective scan images into multiple second quartz wafer groups according to the second grouping method obtained based on the size of the scanning stage, and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform a penetration scan on each second quartz wafer group to obtain the corresponding scan image. Step S3 is repeated until each defective scan image contains only one quartz wafer.

[0010] In step S4, after stopping scanning, the host computer filters out all the quartz wafers corresponding to the defective scan image as defective quartz wafers and retains the remaining quartz wafers as qualified quartz wafers.

[0011] The ultrasonic scanning microscope includes a transducer, and step S1 includes:

[0012] Step S11: The host computer obtains the maximum scanning depth based on the operating frequency of the transducer;

[0013] Step S12: The host computer calculates the maximum number of scans based on the maximum scanning depth and the thickness of the quartz wafer to be inspected, and obtains the maximum number of stacks based on the yield rate;

[0014] Step S13: The host computer selects the minimum value between the maximum number of scans and the maximum number of stacks and rounds it down to obtain the number of the first quartz wafer group as the first grouping method.

[0015] Preferably, step S2 includes:

[0016] Step S21: The operator divides all the quartz wafers to be tested into multiple first quartz wafer groups with a number of wafers equal to the number of the first quartz wafer group and places them on the scanning stage, with each first quartz wafer group located within the scanning range of the ultrasonic scanning microscope.

[0017] In step S22, the host computer controls the ultrasonic scanning microscope to perform a C-scan on each of the first quartz crystal groups in sequence to obtain the corresponding scanning images.

[0018] Preferably, step S3 includes:

[0019] Step S31: The host computer compares each of the scanned images with each other, and identifies scanned images whose differences from other scanned images exceed a set difference threshold as defective scanned images that do not meet the requirements. Then, the host computer determines whether each of the selected defective scanned images contains only one quartz wafer.

[0020] If so, proceed to step S4;

[0021] If not, proceed to step S32;

[0022] In step S32, the host computer calculates the number of second quartz wafer groups based on the size of the scanning stage and the size of the quartz wafers. Then, the operator divides all the quartz wafers corresponding to all the defect scan images into multiple second quartz wafer groups with a number of wafers equal to the number of second quartz wafer groups and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each second quartz wafer group to obtain the corresponding scan image, and then returns to step S31.

[0023] The present invention also provides a rapid screening system for quartz wafers using ultrasound imaging, which applies the rapid screening method for quartz wafers as described above, and includes a host computer and an ultrasound scanning microscope connected to the host computer.

[0024] The host computer includes;

[0025] An initial grouping module is used to determine the maximum scanning depth of the ultrasonic scanning microscope, and then determine the number of the first quartz wafer group as the first grouping method based on the maximum scanning depth, the thickness of the quartz wafer to be tested, and the yield rate.

[0026] The penetration scanning module is connected to the initial grouping module and is used to notify the operator to divide all the quartz crystals to be tested into multiple first quartz crystal groups according to the first grouping method and place them on the scanning stage. Then, the ultrasonic scanning microscope is controlled to perform penetration scanning on each first quartz crystal group to obtain the corresponding scanning image.

[0027] The repeat scanning module, connected to the penetration scanning module, is used to filter out defective scanning images that do not meet the requirements from each of the scanning images. Then, the operator is notified to regroup all the quartz wafers corresponding to all the defective scanning images into multiple second quartz wafer groups according to the second grouping method obtained based on the size of the scanning stage, and place them on the scanning stage for penetration scanning. Then, the second grouping method is repeated multiple times to obtain the corresponding scanning images and filter out the defective scanning images that do not meet the requirements until each defective scanning image contains only one quartz wafer.

[0028] The screening module, connected to the repeat scanning module, is used to screen out all quartz wafers corresponding to the defective scan image as defective quartz wafers after the scanning stops, and retain the remaining quartz wafers as qualified quartz wafers.

[0029] Preferably, the ultrasonic scanning microscope includes a transducer, and the initial grouping module includes:

[0030] A scanning depth calculation unit is used to obtain the maximum scanning depth based on the operating frequency of the transducer;

[0031] The maximum quantity calculation unit is used to calculate the maximum number of scans based on the maximum scanning depth and the thickness of the quartz wafer to be inspected, and to obtain the maximum stacking quantity based on the yield rate.

[0032] The grouping unit, connected to the scanning depth calculation unit and the maximum quantity calculation unit, is used to select the minimum value between the maximum scanning quantity and the maximum stacking quantity and round it down to obtain the first quartz wafer group quantity as the first grouping method.

[0033] Preferably, the penetration scanning module includes:

[0034] The scanning unit is used to instruct the operator to divide all the quartz wafers to be tested into multiple first quartz wafer groups with a number of wafers equal to the number of the first quartz wafer group and place them on the scanning stage, with each first quartz wafer group located within the scanning range of the ultrasonic scanning microscope. Then, the ultrasonic scanning microscope is controlled to perform a C-scan to sequentially scan each group of quartz wafers to obtain the corresponding scan images.

[0035] Preferably, the repeat scan module includes:

[0036] The defect screening unit is used to compare the scanned images with each other and to identify the scanned images whose differences from other scanned images exceed a set difference threshold as defective scanned images that do not meet the requirements.

[0037] The judgment unit, connected to the defect screening unit, is used to calculate the number of second quartz wafer groups based on the size of the scanning stage and the size of the quartz wafer when it is determined that the defective scan image contains more than one quartz wafer. Then, it notifies the operator to divide all the quartz wafers corresponding to all the defective scan images into multiple second quartz wafer groups with a number of wafers equal to the number of the second quartz wafer groups and place them on the scanning stage. Then, it performs a through-scan to obtain the corresponding scan images and filters out the defective scan images that do not meet the requirements. Then, it repeats the second grouping method and performs through-scan multiple times until the filtered defective scan images contain only one quartz wafer.

[0038] The above technical solution has the following advantages or beneficial effects:

[0039] 1) In this invention, an ultrasonic scanning microscope is used for ultrasonic penetration scanning. The ultrasonic scanning microscope has high resolution and high sensitivity, which can accurately capture tiny internal defects, thereby achieving high-precision detection of quartz wafers.

[0040] 2) By performing a through-scan on groups of quartz wafers to be inspected, the defective wafer group can be quickly located, thereby further narrowing the inspection range and improving inspection efficiency.

[0041] 3) During the inspection process, by continuously regrouping and rescanning, the range of defective wafers can be gradually narrowed down until it is accurate to a single wafer, thus achieving precise rejection. Attached Figure Description

[0042] Figure 1 A flowchart illustrating a rapid screening method for quartz crystals using ultrasonic imaging, as a preferred embodiment of the present invention.

[0043] Figure 2 A schematic diagram comparing the maximum scan depth and the maximum stack thickness in a preferred embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of a quartz wafer assembly placed on a scanning stage in a preferred embodiment of the present invention.

[0045] Figure 4 This is a schematic diagram of a sub-process of step S1 in a preferred embodiment of the present invention.

[0046] Figure 5 This is a schematic diagram of a sub-process of step S2 in a preferred embodiment of the present invention;

[0047] Figure 6 This is a schematic diagram of a sub-process of step S3 in a preferred embodiment of the present invention;

[0048] Figure 7 This is a schematic diagram of screening defective quartz wafers in a preferred embodiment of the present invention.

[0049] Figure 8 A schematic diagram of the structure of a rapid screening system for quartz crystals using ultrasonic imaging, as a preferred embodiment of the present invention. Detailed Implementation

[0050] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The present invention is not limited to this embodiment; other embodiments that conform to the spirit of the present invention may also fall within the scope of the present invention.

[0051] In a preferred embodiment of the present invention, based on the above-mentioned problems existing in the prior art, a rapid screening method for quartz crystals using ultrasound imaging is provided, such as... Figure 1 As shown, it includes:

[0052] Step S1: The host computer 300 determines the maximum scanning depth of the ultrasonic scanning microscope 100, and then determines the number of the first quartz wafer group as the first grouping method based on the maximum scanning depth, the thickness of the quartz wafer to be tested, and the yield rate.

[0053] Step S2: The operator divides all the quartz crystals to be tested into multiple first quartz crystal groups according to the first grouping method and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each first quartz crystal group to obtain the corresponding scanning image.

[0054] In step S3, the host computer filters out defective scan images that do not meet the requirements from each scan image. Then, the operator regroups all the quartz wafers corresponding to all defective scan images into multiple second quartz wafer groups according to the second grouping method obtained based on the size of the scanning stage, and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each second quartz wafer group to obtain the corresponding scan image. Step S3 is repeated until each second quartz wafer group corresponding to a defective scan image contains only one quartz wafer.

[0055] In step S4, after stopping scanning, the host computer filters out all quartz wafers corresponding to the defective scan image as defective quartz wafers and retains the remaining quartz wafers as qualified quartz wafers.

[0056] Specifically, in this embodiment, a rapid screening method for quartz wafers using ultrasonic imaging is proposed. An ultrasonic scanning microscope is used to further detect internal defects in quartz wafers after the appearance defect detection, and quartz wafers with internal defects are screened out.

[0057] The first grouping method is determined by the maximum scanning depth of the ultrasonic scanning microscope and the yield rate of the quartz wafers. This limits the number of wafers in each group and the thickness of the group, ensuring that the presence of defective quartz wafers can be accurately detected during the penetration scan of each group, without causing detection errors due to the inability to penetrate the entire group of quartz wafers.

[0058] After each scan, the defective quartz wafers are grouped by comparing the scanned images. Then, based on the size of the scanning stage and the size of the quartz wafers, a second grouping method is determined. The quartz wafers selected each time are continuously regrouped and scanned again, which can gradually narrow down the range of defective wafers until it is accurate to a single wafer, thus achieving precise rejection.

[0059] In a preferred embodiment of the present invention, the ultrasonic scanning microscope includes a transducer, such as... Figure 4 As shown, step S1 includes:

[0060] Step S11: The host computer obtains the maximum scanning depth based on the transducer's operating frequency;

[0061] In step S12, the host computer calculates the maximum number of scans based on the maximum scanning depth and the thickness of the quartz wafer to be inspected, and obtains the maximum number of stacks based on the yield rate.

[0062] Step S13: The host computer selects the minimum value between the maximum number of scans and the maximum number of stacks and rounds it down to get the number of the first quartz crystal group as the first grouping method.

[0063] Specifically, in this embodiment, the minimum value between the maximum number of scans and the maximum number of stacks is selected to determine the number of the first quartz wafer group as the first grouping method. The thickness of the quartz wafer group obtained according to the first grouping method is neither greater than the maximum scanning depth nor greater than the maximum stacking thickness calculated based on the maximum number of stacks and the thickness of the quartz wafer to be detected. During penetration scanning, it can accurately detect whether there are defective quartz wafers in the group, and will not cause detection errors due to the inability to penetrate the entire group of quartz wafers.

[0064] Specifically, in this embodiment, the maximum scanning depth of the ultrasonic scanning microscope is determined by the operating frequency of the transducer. A higher transducer operating frequency results in a smaller maximum scanning depth and higher theoretical resolution; conversely, a lower operating frequency leads to a larger maximum scanning depth and lower theoretical resolution.

[0065]

[0066] Where d is the maximum scanning depth and f is the transducer operating frequency. Typically, the transducer operating frequency is 20MHz; at 30MHz, the maximum scanning depth is 3–4mm.

[0067] The quartz crystal wafers used in crystal resonators are typically tens to hundreds of micrometers thick, far smaller than the maximum scanning depth of an ultrasonic scanning microscope. A single scan can penetrate tens to hundreds of quartz crystal wafers. Let the transducer operating frequency be f. w The maximum scanning depth of the ultrasonic scanning microscope is D mm, which is converted into the maximum number of quartz wafers of a certain thickness y, rounded down to P (P = D / y).

[0068] Generally, quartz wafer manufacturers have clear control over the yield rate. Let's assume, based on past testing experience, the achievable yield rate is η, which translates to a maximum stacking quantity of N quartz wafers. Let the total thickness of these stacked wafers be L mm. (See attached diagram.) Figure 2 As shown. The rapid screening method for internal defects in quartz wafers of this invention is manifested in the following steps: First, the manufactured quartz wafers are grouped and stacked vertically together. There are strict requirements on the number of groups of quartz wafers. The total stacked thickness of a certain number of groups of quartz wafers cannot exceed the maximum scanning depth Dmm of the ultrasonic scanning microscope at a defined operating frequency, nor can it exceed the thickness Lmm calculated from the quartz wafer yield rate. Furthermore, this number must be an even number.

[0069]

[0070] Where M represents the number of quartz wafer groups. After selecting the number M, the quartz wafer groups are scanned and imaged using the C-scan mode of an ultrasonic scanning microscope. Based on the yield control of the quartz wafer manufacturer, the number of groups is reasonably set. Due to the constraint of the number of groups M, the number of defective quartz wafers in each group is extremely low, thereby optimizing the probability of defects in the scanned images. This ensures that only a small portion of the quartz wafer groups contain defective quartz wafers after scanning, making it easy to distinguish defective scanned images and improving screening efficiency.

[0071] Because the transducer's operating frequency is adjustable, the scanning depth and number of groups can be flexibly adjusted according to different quartz wafer thicknesses and detection requirements to meet the needs of different production scenarios.

[0072] In a preferred embodiment of the present invention, such as Figure 5 As shown, step S2 includes:

[0073] Step S21: The operator divides all the quartz crystals to be tested into multiple first quartz crystal groups with the same number of crystals as the first quartz crystal group and places them on the scanning stage, with each first quartz crystal group located within the scanning range of the ultrasonic scanning microscope.

[0074] Step S22: The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each group of first quartz crystals in C-scan mode to obtain the corresponding scanning images.

[0075] Specifically, in this embodiment, to improve the screening speed and accuracy, a method is adopted to simultaneously scan multiple groups of quartz wafers to obtain scanned images and compare the scan results together. That is, under a certain detection environment, K groups of quartz wafers are placed simultaneously for C-scan imaging. The number of quartz wafers in each group is no greater than the number in the first quartz wafer group. The value of K can be determined according to the actual placement space of the operating table, but it is necessary to ensure that each group of quartz wafers is within the scanning range. Factors such as the effectiveness of mutual comparison should be flexibly adjusted, and it is recommended to set it to several tens to hundreds of groups. The group scanning environment is shown in the attached figure. Figure 3 As shown. Under this scanning environment, a single scan produces K C-scan images of a quartz crystal wafer array.

[0076] Specifically, the step of placing each quartz crystal wafer group on the scanning stage can be done by a robotic arm controlled by a host computer. However, considering the thickness, hardness, and size of the quartz wafers, it is safer to use a manual grouping method.

[0077] In this embodiment, simultaneous scanning of multiple quartz crystal wafer groups can greatly shorten the overall detection time, increase the screening speed, and make the entire production process more efficient.

[0078] Depending on factors such as the actual space available for the operating table and the scanning effect, the number of quartz wafer groups being scanned simultaneously (i.e., the K value) can be flexibly adjusted to adapt to different production environments and needs.

[0079] When placing quartz wafers in groups, by rationally arranging the scanning order and position of multiple groups of quartz wafers, such as an array with equal spacing, the scanning capability of the ultrasonic scanning microscope can be maximized, the travel distance of the ultrasonic scanning microscope can be reduced, the scanning efficiency can be improved, and resource utilization can be optimized.

[0080] In a preferred embodiment of the present invention, such as Figure 6 As shown, step S3 includes:

[0081] Step S31: The host computer compares each scanned image with the others and identifies scanned images whose differences from other scanned images exceed a set difference threshold as defective scanned images that do not meet the requirements. The host computer then determines whether each selected defective scanned image contains only one quartz wafer.

[0082] If so, proceed to step S4;

[0083] If not, proceed to step S32;

[0084] In step S32, the host computer calculates the number of second quartz wafer groups based on the size of the scanning stage and the size of the quartz wafers. Then, the operator divides all the quartz wafers corresponding to all the defect scan images into multiple second quartz wafer groups with a number of wafers equal to the number of second quartz wafer groups and places them on the scanning stage. The host computer controls the ultrasonic scanning microscope to perform penetration scanning on each second quartz wafer group to obtain the corresponding scan image, and then returns to step S31.

[0085] Specifically, in this embodiment, one scan has been completed, resulting in K C-scan images of quartz wafer groups. These K images are compared with each other. Based on this screening mode, due to the constraint of M, the number of defective quartz wafers in each group is extremely low, and the vast majority of images are good. The differences between the obtained scan images are minimal, and groups with essentially no differences are judged as good. Images with significant differences after comparison are selected as defective scan images, indicating that there are likely defective products in the corresponding quartz wafer group. The quartz wafers in these groups are then regrouped in a second-level grouping manner, that is, the number of quartz wafer groups at this time is:

[0086]

[0087] Where M new K represents the number of quartz wafers in each group after regrouping, x represents the total number of quartz wafers in the previously identified defective groups, and K represents the number of quartz wafers in each group. new M represents the number of quartz crystal groups after regrouping. new K new The number of x will be updated with each grouping. It needs to be determined based on the actual situation, taking into account the size of the workbench and the size of the quartz wafers. Assuming that the defective scan images correspond to 20 quartz wafers, and the workbench can accommodate at least 20 quartz wafers, then regrouping into 5 groups of 4 wafers each, or regrouping into 4 groups of 5 wafers each, or even into 20 groups of 1 wafer each are all possible regrouping methods.

[0088] Since it is currently unknown which quartz crystals in the quartz crystal assembly will exhibit defects, it is necessary to further analyze the K crystals after secondary grouping. new The quartz wafers were then subjected to further ultrasonic C-scan imaging, which also required the analysis of the obtained K-series scans. new By comparing the images, groups with significant differences are selected, and these groups of quartz wafers need to be further grouped. To screen out quartz wafers with internal defects, the above grouping, scanning, and screening processes need to be repeated until, after a certain grouping, each group contains only one quartz wafer. Defective quartz wafers are then identified, and the final result of the defective quartz wafers is shown in the attached figure. Figure 7 As shown.

[0089] Specifically, to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0090] If the ultrasonic scanning microscope operates at a frequency of 30MHz and has a maximum scanning depth of 3mm, and the batch of quartz wafers with a thickness of 32μm needs to be screened, then theoretically a maximum of 93.75 quartz wafers can be scanned at once, that is, the maximum number of scans P = 93.75 wafers.

[0091] If the yield rate after visual defect inspection is η = 99.3%, and the maximum stacking quantity of quartz wafers is N = 99.3 wafers per hundred wafers, this indicates that the probability of a defective wafer appearing out of 100 wafers is less than 1. In this case, the rapid screening method of this invention requires a grouping quantity of quartz wafers of [specific value missing].

[0092]

[0093] The method for determining M can be found in the appendix. Figure 2 For ease of grouping and calculation, we take M = 92 pieces. Assuming a total of 920 quartz crystals need to be inspected, and testing shows that 10 groups of quartz crystal wafers can be placed on the scanning stage for simultaneous scanning, we take K = 10. This means the ultrasonic scanning microscope scans 10 groups of quartz crystal wafers at a time, with 92 wafers in each group. Due to the method used to calculate the number of groups, the probability of a quartz crystal with internal defects in each group is very small, less than one. Therefore, the differences in the 10 images obtained from the C-scan are generally small, and the number of groups with defects is extremely small, or even nonexistent. The grouping scanning method can be found in the appendix. Figure 3 .

[0094] In this example, if the scanned images of two groups of quartz wafers differ significantly and may indicate a defect, then to identify the specific defective wafer, it is necessary to further regroup these two groups of 184 quartz wafers. Considering the number of quartz wafers, let's assume that this (second level) regrouping involves 8 groups, with 23 wafers in each group.

[0095] If, after regrouping and scanning, the ultrasound C-scan images reveal two groups of quartz wafers that may have internal defects, these two groups (46 wafers in total) need to be regrouped and scanned again. Let's assume this (level 3) regrouping involves 10 groups, with 4 groups containing 4 wafers and the other 6 groups containing 5 wafers. If the ultrasound C-scan images reveal two groups of 4 wafers that may have internal defects, then these two groups (8 wafers in total) need to be regrouped a final time, resulting in 8 groups of one wafer per group. At this point, ultrasound C-scans can then be performed to screen out the defective wafers. If three images show abnormalities, the corresponding three wafers can be selected. For instructions on screening quartz wafers with internal defects, please refer to the appendix. Figure 7 .

[0096] This invention also provides a rapid quartz wafer screening system using ultrasound imaging, applying the rapid quartz wafer screening method described above, such as... Figure 8 As shown, it includes a host computer 300 and an ultrasonic scanning microscope 100 connected to the host computer 300;

[0097] Initial grouping module 1 is used to determine the maximum scanning depth of the ultrasonic scanning microscope, and then determine the number of the first quartz wafer group as the first grouping method based on the maximum scanning depth, the thickness of the quartz wafer to be tested, and the yield rate.

[0098] The penetration scanning module 2 is connected to the initial grouping module 1. It is used to notify the operator to divide all the quartz crystals to be tested into multiple first quartz crystal groups according to the first grouping method and place them on the scanning stage. Then, the ultrasonic scanning microscope is controlled to perform penetration scanning on each first quartz crystal group to obtain the corresponding scanning image.

[0099] The repeat scanning module 3, connected to the penetration scanning module 2, is used to filter out defective scanning images that do not meet the requirements from each scanning image. Then, the operator is notified to regroup all the quartz wafers corresponding to all defective scanning images into multiple second quartz wafer groups according to the second grouping method obtained based on the size of the scanning stage, and place them on the scanning stage for penetration scanning. Then, the second grouping method is repeated multiple times to obtain the corresponding scanning images and filter out the defective scanning images that do not meet the requirements until the filtered defective scanning images contain only one quartz wafer.

[0100] The screening module 4 is connected to the repeat scanning module 3. After the scanning stops, it screens out all quartz wafers corresponding to the defective scan image as defective quartz wafers and retains the remaining quartz wafers as qualified quartz wafers.

[0101] In a preferred embodiment of the present invention, the ultrasonic scanning microscope includes a transducer, such as... Figure 8 As shown, the initial grouping module 1 includes:

[0102] The scanning depth calculation unit 11 is used to obtain the maximum scanning depth based on the operating frequency of the transducer.

[0103] The maximum quantity calculation unit 12 is used to calculate the maximum number of scans based on the maximum scanning depth and the thickness of the quartz wafer to be inspected, and to obtain the maximum stacking quantity based on the yield rate.

[0104] Grouping unit 13, connected to scanning depth calculation unit 11 and maximum quantity calculation unit 12, is used to select the minimum value between maximum scanning quantity and maximum stacking quantity and round it down as the first quartz wafer group quantity as the first grouping method.

[0105] In a preferred embodiment of the present invention, such as Figure 8 As shown, the penetration scanning module 2 includes:

[0106] The scanning unit 21 is used to notify the operator to divide all the quartz crystals to be tested into multiple first quartz crystal groups with the same number of crystals as the first quartz crystal group and place them on the scanning stage. Each first quartz crystal group is located within the scanning range of the ultrasonic scanning microscope. Then, the ultrasonic scanning microscope is controlled to perform a C-scan to sequentially scan each group of quartz crystals to obtain the corresponding scan image.

[0107] Specifically, the process of placing each quartz crystal wafer group on the scanning stage can be done using a robotic arm controlled by a host computer. However, considering the thickness, hardness, and size of the quartz wafers, it is safer to use a manual grouping method.

[0108] In a preferred embodiment of the present invention, such as Figure 8 As shown, the repeat scan module 3 includes:

[0109] The defect screening unit 31 is used to compare the scanned images with each other and to identify the scanned images whose differences from other scanned images exceed a set difference threshold as defective scanned images that do not meet the requirements.

[0110] The judgment unit 32, connected to the defect screening unit 31, is used to calculate the number of second quartz wafer groups based on the size of the scanning stage and the size of the quartz wafers when the quartz wafer group corresponding to the defective scan image contains more than one quartz wafer. Then, it notifies the operator to divide all the quartz wafers corresponding to all defective scan images into multiple second quartz wafer groups with the same number of wafers as the number of second quartz wafer groups, and place them on the scanning stage for transmission scanning to obtain the corresponding scan images. The defective scan images that do not meet the requirements are then screened out. The second grouping method is then repeated multiple times and transmission scanning is performed until the screened defective scan images contain only one quartz wafer.

[0111] The above are merely preferred embodiments of the present invention and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should recognize that any equivalent substitutions and obvious changes made using the content of this specification and illustrations should be included within the protection scope of the present invention.

Claims

1. A method for rapid screening of quartz wafers using ultrasonic imaging, characterized in that: include: Step S1, the host computer determines the maximum scanning depth of the ultrasonic scanning microscope, and then determines the number of the first quartz wafer group as the first grouping method according to the maximum scanning depth and the thickness and yield rate of the quartz wafer to be detected; Step S2, the operator divides all the quartz wafers to be inspected into a plurality of first quartz wafer groups according to the first grouping method and places them on a scanning table, and the host computer controls the ultrasonic scanning microscope to perform penetration scanning on each of the first quartz wafer groups to obtain a corresponding scanning image; Step S3, the host computer screens out defective scanning images that do not meet the requirements from each of the scanning images, and then the operator re-divides all the quartz wafers corresponding to all the defective scanning images into multiple second quartz wafer groups according to the second grouping method obtained according to the size of the scanning table and places them on the scanning table, and the host computer controls the ultrasonic scanning microscope to perform penetration scanning on each of the second quartz wafer groups to obtain the corresponding scanning images, and repeats step S3 until each of the defective scanning images contains only one quartz wafer; Step S4, after stopping scanning, the host computer screens out all quartz wafers corresponding to the defective scanning image as defective quartz wafers, and retains the remaining quartz wafers as qualified quartz wafers.

2. The quartz wafer rapid screening method according to claim 1, wherein the ultrasonic scanning microscope comprises a transducer, characterized in that: The step S1 comprises: Step S11, the host computer obtains the maximum scanning depth according to the operating frequency of the transducer; Step S12, the host computer calculates the maximum scanning quantity according to the maximum scanning depth and the thickness of the quartz wafer to be detected, and obtains the maximum stacking quantity according to the yield rate; Step S13, the host computer selects the minimum value between the maximum scanning quantity and the maximum stacking quantity and rounds it down to obtain the first quartz wafer group quantity as a first grouping method.

3. The quartz wafer rapid screening method according to claim 1, characterized in that: The step S2 comprises: Step S21, the operator divides all the quartz wafers to be inspected into a plurality of first quartz wafer groups whose number of wafers is equal to the number of the first quartz wafer groups and places them on a scanning table, and each of the first quartz wafer groups is located within the scanning range of the ultrasonic scanning microscope; Step S22: the host computer controls the ultrasonic scanning microscope to perform penetration scanning on each of the first quartz wafer groups in sequence using a C scanning mode to obtain corresponding scanning images.

4. The quartz wafer rapid screening method according to claim 1, characterized in that: The step S3 comprises: Step S31, the host computer compares the scanned images with each other, and regards the scanned images whose difference with other scanned images exceeds the set difference threshold as the defective scanned images that do not meet the requirements, and then the host computer determines whether each of the screened defective scanned images contains only one quartz wafer: If yes, go to step S4; If not, go to step S32; Step S32, the host computer calculates the number of second quartz wafer groups according to the size of the scanning platform and the size of the quartz wafer, and then the operator divides all quartz wafers corresponding to all defect scanning images into multiple second quartz wafer groups with a number of wafers equal to the number of second quartz wafer groups and places them on the scanning platform, and the host computer controls the ultrasonic scanning microscope to perform penetration scanning on each of the second quartz wafer groups to obtain a corresponding scanning image, and then returns to step S31.

5. A quartz wafer rapid screening system using ultrasonic imaging, characterized in that: A quartz wafer rapid screening method according to any one of claims 1 to 4 is applied, comprising a host computer and an ultrasonic scanning microscope connected to the host computer; The host computer comprises: An initial grouping module, used to determine a maximum scanning depth of the ultrasonic scanning microscope, and then determine the number of first quartz wafer groups as a first grouping method according to the maximum scanning depth and the thickness and yield rate of the quartz wafer to be detected; a penetration scanning module, connected to the initial grouping module, for notifying an operator to divide all the quartz wafers to be inspected into a plurality of first quartz wafer groups according to the first grouping method and place the groups on a scanning table, and then controlling the ultrasonic scanning microscope to perform penetration scanning on each of the first quartz wafer groups to obtain a corresponding scanning image; a repeated scanning module, connected to the penetration scanning module, for screening out defective scanning images that do not meet the requirements from each of the scanning images, and then notifying the operator to re-divide all quartz wafers corresponding to all the defective scanning images into a plurality of second quartz wafer groups according to a second grouping method obtained according to the size of the scanning table and place the second quartz wafer groups on the scanning table for penetration scanning, and then repeatedly performing the second grouping method grouping and penetration scanning to obtain corresponding scanning images to screen out defective scanning images that do not meet the requirements, until each of the defective scanning images contains only one quartz wafer; A screening module is connected to the repeated scanning module and is used to screen out all quartz wafers corresponding to the defective scanning image as defective quartz wafers after stopping scanning, and retain the remaining quartz wafers as qualified quartz wafers.

6. The quartz wafer rapid screening system according to claim 5, wherein the ultrasonic scanning microscope comprises a transducer, characterized in that: The initial grouping module comprises: A scanning depth calculation unit, used to obtain the maximum scanning depth according to the operating frequency of the transducer; A maximum number calculation unit, used for calculating the maximum scanning number according to the maximum scanning depth and the thickness of the quartz wafer to be detected, and obtaining the maximum stacking number according to the yield rate; A grouping unit is connected to the scanning depth calculation unit and the maximum number calculation unit, and is used to select a minimum value between the maximum scanning number and the maximum stacking number and round it down to obtain the first quartz wafer group number as the first grouping method.

7. The quartz wafer rapid screening system according to claim 5, characterized in that: The penetration scanning module comprises: The scanning unit is used to notify the operator to divide all the quartz wafers to be inspected into a plurality of first quartz wafer groups whose number of wafers is equal to the number of the first quartz wafer groups and place them on a scanning table, and each of the first quartz wafer groups is located within the scanning range of the ultrasonic scanning microscope, and then control the ultrasonic scanning microscope to use a C scanning mode to perform penetration scanning on each of the quartz wafer groups in turn to obtain a corresponding scanning image.

8. The quartz wafer rapid screening system according to claim 5, characterized in that: The repeated scanning module comprises: A defect screening unit, used for comparing the scanned images with each other, and treating the scanned images whose difference with other scanned images exceeds a set difference threshold as defective scanned images that do not meet the requirements; A judgment unit connected to the defect screening unit is used for calculating the number of second quartz wafer groups according to the size of the scanning platform and the size of the quartz wafer when judging that the defect scanning image contains more than one quartz wafer, and then notifying the operator to divide all quartz wafers corresponding to all the defect scanning images into multiple second quartz wafer groups with the number of wafers equal to the number of the second quartz wafer groups and place them on the scanning platform, and then performing a penetration scan to obtain the corresponding scanning image to screen out the defect scanning image that does not meet the requirements, and then repeatedly performing the second grouping method grouping and performing the penetration scan until the screened defect scanning image contains only one quartz wafer.

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