Wafer detection method, device and storage medium

Abstract

The present invention discloses a wafer detection method, device and storage medium. The method is used for detecting the state of wafers in a wafer boat. The wafer states include single wafers, oblique wafers and stacked wafers. The wafer boat includes a plurality of tooth grooves arranged along a first direction for wafer placement. The detection method includes scanning and detecting all wafers in the wafer boat in sequence in a first direction through a sensor on a fork; obtaining a first height value when the sensor detects each wafer and a second height value when the sensor leaves the wafer; obtaining the tooth groove number corresponding to the first height value and the second height value by matching; calculating the sensing length of a wafer according to the first height value and the second height value; and determining whether there is an abnormality in the wafer state and the tooth groove based on the range of the sensing length. When a sensor detects the state of the wafer in the wafer boat, it can also check the abnormality of the tooth groove of the wafer boat, and promptly find abnormal wafers and tooth grooves.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a wafer detection method, device and storage medium. Background Art

[0002] The safe placement and access of wafers is a very important technical indicator of semiconductor production lines. In the semiconductor production process, each production process requires a lot of wafer transfer, wafer placement and wafer retrieval, so the safety and reliability of wafer transfer, wafer placement and wafer retrieval are required to be high. The wafers will be placed in the wafer boat, and the wafers in the wafer boat will be placed and accessed by the wafer fork. Before the wafer is grabbed, the wafer fork will detect the wafers in the wafer boat to detect the tilt and stacking problems of the wafer in time, so as to improve the safety of wafer retrieval.

[0003] Commonly used wafer boats include integrated wafer boats and modular wafer boats. Integrated wafer boats are commonly made of silicon carbide wafer boats, which have high performance in terms of high temperature resistance and service life, but silicon nitride wafer boats are difficult to process and expensive. The modular wafer boat can combine the various components of the wafer boat into one by means of snaps, threads, and welding with adhesives. Since the components of the modular wafer boat can be processed first and then assembled into shape, the modular wafer boat can overcome the disadvantage of being difficult to process. After being subjected to high temperatures for many times, the modular wafer boat will deform, causing the wafer placed on it to tilt, or be judged as a stack by the sensor on the wafer fork, affecting the detection results of the wafer. Therefore, how to detect abnormalities in the wafer boat in a timely manner while detecting the wafer has become a technical problem to be solved. Summary of the invention

[0004] In order to overcome the above-mentioned shortcomings, the purpose of the present invention is to provide a wafer detection method, equipment and storage medium, in which a sensor can detect the state of the wafers in the wafer boat and at the same time check the abnormal conditions of the wafer boat grooves, and promptly discover abnormal wafers and grooves.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A wafer detection method is used for detecting the state of a wafer boat and wafers in the wafer boat, wherein the wafer state includes a single wafer, an inclined wafer, and a stacked wafer, and the wafer boat includes a plurality of tooth grooves arranged along a first direction for placing wafers, and the detection method includes:

[0007] All wafers in the wafer boat are scanned and detected in sequence in a first direction by a sensor on the wafer fork;

[0008] Obtaining a first height value when the sensor detects each wafer and a second height value when the sensor leaves the wafer;

[0009] Acquire the tooth groove number corresponding to the first height value and the second height value by matching;

[0010] Calculating a sensing length of a wafer according to the first height value and the second height value;

[0011] Based on the range of the sensing length, determine whether the wafer status and tooth groove are abnormal, including:

[0012] When the sensing length is greater than a first threshold, the wafer is a slanted wafer;

[0013] Compare the sensed length with the first threshold, the second threshold and the third threshold, and determine whether there is an abnormal tooth groove in the area where the inclined piece is located according to the comparison result;

[0014] When an abnormal tooth groove exists in the area where the inclined piece is located, the tooth groove number of the abnormal tooth groove is determined according to the deviation degree between the first height value and the second height value.

[0015] Specifically, comparing the sensing length with the first threshold, the second threshold, and the third threshold, and judging whether there is an abnormal tooth groove in the area where the inclined piece is located according to the comparison result specifically includes:

[0016] When the sensing length is greater than the second threshold, or the sensing length is greater than the first threshold and less than the third threshold, an abnormal tooth groove exists in the area where the inclined piece is located.

[0017] Further, according to the deviation degree between the first height value and the second height value, determining the tooth groove number of the abnormal tooth groove specifically includes:

[0018] The first height value and the second height value are compared with the third height value and the fourth height value respectively, and when the absolute value of the difference between the first height value and the third height value and / or the absolute value of the difference between the second height value and the fourth height value is greater than or equal to a fourth threshold value, the tooth groove number corresponding to the first height value and / or the second height value is abnormal;

[0019] The third height value is the height value corresponding to the sensor signal jumping when the sensor senses the wafer when the wafer is placed obliquely in the two-layer tooth groove of the standard wafer boat corresponding to the first height value and the second height value. The fourth height value is the height value corresponding to the sensor signal jumping again when the sensor leaves the wafer when the wafer is placed obliquely in the two-layer tooth groove of the standard wafer boat corresponding to the first height value and the second height value.

[0020] Furthermore, based on the range of the sensing length, determining whether the wafer state and the tooth groove are abnormal includes:

[0021] When the sensing length is greater than a fifth threshold value and less than a sixth threshold value, the wafer is a single piece and the tooth groove where the wafer is located causes the wafer to tilt;

[0022] Determining whether the difference between the sensing length and the thickness of the wafer is greater than a fourth threshold;

[0023] If so, the tooth groove where the wafer is located is abnormal.

[0024] Furthermore, based on the range of the sensing length, determining whether the wafer state and the tooth groove are abnormal includes:

[0025] When the sensing length is greater than or equal to the sixth threshold value and less than or equal to the seventh threshold value, the first height value is compared with the fifth height value, and the fifth height value is the height value corresponding to the sensor signal jumping when the sensor senses the wafer when the wafer is set in the tooth groove corresponding to the first height value of the standard wafer boat;

[0026] If the first height value is equal to the fifth height value, the wafer is a stacked wafer. If the first height value is not equal to the fifth height value, there is an abnormality in the tooth groove corresponding to the first height value.

[0027] Further, based on the range of the sensing length, determining the state of the wafer and the state of the tooth groove also includes:

[0028] When the sensing length is greater than or equal to the thickness of the wafer and less than or equal to the fifth threshold, the wafer is a single piece and the tooth grooves corresponding to the wafer are normal.

[0029] Further, obtaining the tooth groove number corresponding to the first height value and the second height value by matching specifically includes:

[0030] Obtain a data set when a single wafer is inserted into each layer of slots in a standard wafer boat, the data set includes the slot number and the corresponding area height range;

[0031] The data set is traversed to find the area height range corresponding to the first height value and the second height value to determine the tooth groove number.

[0032] Furthermore, the sensing length is the absolute value of the difference between the first height value and the second height value.

[0033] The present invention also discloses a wafer detection device, comprising a wafer fork, on which a sensor is arranged, and the sensor sequentially scans and detects the wafers in the wafer boat in a first direction. The detection device adopts the above-mentioned wafer detection method.

[0034] The present invention also discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned wafer detection method are implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of a detection method in one embodiment of the present invention;

[0036] Figure 2 A schematic diagram of a wafer in a wafer boat according to an embodiment of the present invention;

[0037] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0038] Figure 4 for Figure 2 Enlarged view of point B in the middle;

[0039] Figure 5 for Figure 2 Enlarged view of point C in the middle;

[0040] Figure 6 A state diagram of a sensor scanning a wafer in one embodiment of the present invention;

[0041] Figure 7 Schematic diagram of the structure of a wafer inspection device in one embodiment of the present invention. DETAILED DESCRIPTION

[0042] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0043] The wafer detection method of the present invention is used to detect the tooth groove of the wafer boat 1 and the wafer state detection in the wafer boat 1. The wafer state includes single wafer, oblique wafer and stacked wafer. Figure 2 As shown, the wafer boat 1 includes a plurality of tooth grooves 11 evenly arranged along a first direction for placing wafers 2, and the wafer boat 1 includes a support portion 12, and the spacing between adjacent support portions 12 in the first direction is the same, and a tooth groove 11 is formed between adjacent support portions 12 in the first direction. Normally, only one wafer 2 can be placed in one tooth groove 11, and when the wafer 2 is inserted into the tooth groove 11, the wafer 2 is carried on a support portion 12 located below the tooth groove 11.

[0044] The wafers in this embodiment are all standard wafers, that is, in this embodiment, the warping problem of the wafer itself is not considered.

[0045] See attached Figure 1 As shown, the detection method includes:

[0046] S1 . Scan and detect all wafers in the wafer boat in sequence in a first direction through the sensor 31 on the wafer fork 3 .

[0047] The first direction is the up-down direction. The fork can scan from bottom to top or from top to bottom. The fork should be able to cover the entire wafer boat during one scanning process.

[0048] S2. Obtain a first height value when the sensor detects each wafer and a second height value when the sensor leaves the wafer.

[0049] The sensor includes a transmitting end and a receiving end, and a horizontal detection light 4 is formed between the reflecting end and the receiving end. The wafer has a certain thickness. When the wafer is detected, the detection light will be blocked, and a signal will be generated at this time. Therefore, when the sensor detects a wafer, the sensor will generate a signal jump when it just detects and leaves the wafer. According to the signal jump of the sensor, the first height value and the second height value detected by the sensor can be obtained through the Z-axis encoder. The first height value and the second height value form a data pair, and the data pair corresponds to the wafer one by one.

[0050] S3. Obtain the tooth groove number corresponding to the first height value and the second height value by matching.

[0051] Step S3 specifically includes:

[0052] S31, obtaining a data set when a single wafer is inserted into each layer of tooth slots in a standard wafer boat, the data set including a tooth slot number and a corresponding area height range.

[0053] The standard wafer boat and the wafer boat are the same type of wafer boat. The standard wafer boat needs to ensure that there is no abnormality in the tooth groove, that is, the standard wafer boat does not have uneven tooth grooves for placing the same wafer. The wafer inserted in the tooth groove is a standard wafer. The standard wafer and the wafer are the same type of wafer. The standard wafer needs to ensure that there is no abnormality such as warping. The regional height range is the height area corresponding to each layer of the tooth groove of the standard wafer boat.

[0054] The data set is acquired and stored in advance before wafer inspection. When each wafer boat of the same type is inspected, this data set can be called to search for the tooth slot number.

[0055] S32, traversing the data set, searching for the area height range corresponding to the first height value and the second height value to determine the tooth groove number.

[0056] For example, the wafer boat has 5 layers of tooth grooves, the height of each layer of tooth grooves is 10, and the height of the support portion is 5. Then the data set from the first layer of tooth grooves to the fifth layer of tooth grooves is {(0-10, first layer) (15-25, second layer), (30-40, third layer), (45-55, fourth layer), (60-70, fifth layer)}. When the first height value is 35, the tooth groove number corresponding to the first height value is 3, and when the second height value is 45, the tooth groove number corresponding to the second height value is 4.

[0057] S4. Calculate the sensing length of a wafer according to the first height value and the second height value.

[0058] The sensing length is the absolute value of the difference between the first height value and the second height value. For example, when the first height value is 35 and the second height value is 40, the sensing length corresponding to the wafer is 5.

[0059] S5. Determine whether there is any abnormality in the wafer state and the tooth groove based on the range of the sensing length.

[0060] Because the wafer boat will rise and fall with the lifting platform when in use, it is not convenient to detect the tooth grooves of the wafer boat after the wafer boat is installed on the lifting platform. However, the modular wafer boat may become unstable after being subjected to high temperatures for many times, and the tooth grooves of the wafer boat where the same wafer is placed may be uneven. Wafers placed on uneven tooth grooves will be slightly tilted, and the probability of placing the wafer in the tooth groove of the wafer boat from the wafer box will also increase. Therefore, in this embodiment, through the preset algorithm, while detecting the state of the wafer, it is possible to detect whether there is an abnormality in the tooth groove, and the abnormal tooth groove can be discovered in time, and the wafer boat can be replaced or adjusted in time.

[0061] Step S5 specifically includes:

[0062] S511: When the sensing length is greater than a first threshold, the wafer is a tilted wafer.

[0063] The sensing length is L, and the first threshold is (h1+2d)*λ, that is, when L> When , the detected wafer is a tilted wafer. Where d is the thickness of the wafer, h1 is the thickness of the support part, and λ is the position proportional coefficient of the sensor. , see attached Figure 6 As shown, is the radius of the wafer, and S is the vertical distance from the center o of the wafer to the detection light.

[0064] When the wafer is a bevel, the bevel will span two adjacent tooth grooves in the up and down directions, so the detected sensing length will be larger. The bevel has at least a thickness of d in the tooth groove, and the bevel is exposed for at least a thickness of d, so the value h1+2d is selected as a reference. However, h1+2d is the inclination of the position corresponding to a diameter of the wafer, but the incident light does not pass through the center of the wafer, but deviates a certain distance from the center of the wafer in the front and back directions toward the opening of the wafer boat, so the proportional coefficient needs to be calculated. When the sensing length is greater than (h1+2d)*λ, this wafer state must be a bevel.

[0065] S512: Compare the sensing length with the first threshold, the second threshold, and the third threshold, and determine whether there is an abnormal tooth groove in the area where the inclined piece is located according to the comparison result.

[0066] After judging whether the wafer is beveled, it may be that only the wafer is beveled, or there may be abnormalities in the tooth grooves while beveled, so further judgment is required.

[0067] The comparison of the sensing length with the first threshold, the second threshold and the third threshold is to obtain the degree of inclination of the bevel relative to the standard bevel, which is the bevel inserted into the standard wafer boat. When the bevel is tilted too much or too little, there are abnormal teeth in the area where the bevel is located.

[0068] S513: When there is an abnormal tooth groove in the area where the inclined piece is located, determine the tooth groove number of the abnormal tooth groove according to the deviation degree between the first height value and the second height value.

[0069] Through step S512, it can only be determined that the region where the oblique sheet is located has abnormal tooth grooves, but the oblique sheet spans two tooth grooves, so it is necessary to further determine which layer of tooth grooves has the abnormality.

[0070] Through steps S511-S513, the abnormality of the tooth groove can be judged while the inclined piece is judged, and the abnormal tooth groove number can be found in time. This process is completed during the sensor performing a detection scan, and no additional detection mechanism is required.

[0071] Step S512 specifically includes:

[0072] When the sensing length is greater than the second threshold, or the sensing length is greater than the first threshold and less than the third threshold, an abnormal tooth groove exists in the area where the inclined piece is located.

[0073] The second threshold is (h1+h2+ε+ξ1)*λ, and the third threshold is (h1+h2+ε-ξ2)*λ, see Appendix Figure 3 As shown, h2 is the height of the tooth groove, ε is the lowest height of the wafer exposed in the tooth groove of the standard wafer boat when it is placed obliquely, and ξ1 is the threshold value for the support part contacting the upper end of the inclined plate to move upward or the support part contacting the lower end of the inclined plate to move downward ( Figure 3 The support part with the middle dotted line is the offset support part), ξ2 is the threshold value for the support part in contact with the upper end of the inclined plate to move downward or the support part in contact with the lower end of the inclined plate to move upward, if ξ1 or ξ2 is exceeded, at least one of the two support parts in contact with the inclined plate is abnormal, the values ​​of ξ1 and ξ2 can be the same, both are ξ, ξ is the offset distance threshold of the support part relative to the standard position in the first direction, ξ1 and ξ2 can also be different, which are set artificially.

[0074] In this embodiment, ε, ξ1 and ξ2 are collected in advance, and by comparing with the ideal situation, it is determined whether there are abnormal tooth grooves in the area where the bevel is located. When L>(h1+h2+ε+ξ1)*λ, it means that the inclination of the bevel is greater than the inclination of the standard bevel in the standard wafer boat. At this time, there is a situation where the support part against the upper part of the wafer moves up or / and the support part against the lower part of the wafer moves down. When (h1+2d)*λ<L<(h1+h2+ε-ξ2)*λ, it means that the inclination of the bevel is less than the inclination of the standard bevel in the standard wafer boat. At this time, there is a situation where the support part against the upper part of the wafer moves down or / and the support part against the lower part of the wafer moves up. In both cases, there are abnormal tooth grooves in the area where the bevel is located.

[0075] When (h1+h2+ε-ξ2)*λ≤L≤(h1+h2+ε+ξ1)*λ, there are no abnormal teeth in the area where the oblique piece is located.

[0076] The inclined plate spans two tooth grooves, and the tooth groove numbers of the layers where the lower and upper parts of the inclined plate are located can be determined according to the first height value and the second height value. At this time, the two tooth groove numbers are different. However, after step S512, which of the two tooth grooves where the inclined plate is located has a problem needs to be further determined.

[0077] Step S513 specifically includes:

[0078] The first height value and the second height value are compared with the third height value and the fourth height value respectively. When the absolute value of the difference between the first height value and the third height value and / or the absolute value of the difference between the second height value and the fourth height value is greater than or equal to the fourth threshold value, the tooth groove number corresponding to the first height value and / or the second height value is abnormal. The third height value is the height value corresponding to the sensor signal jumping when the sensor senses the wafer when the wafer is placed obliquely in the two layers of tooth grooves corresponding to the first height value and the second height value of the standard wafer boat, and the fourth height value is the height value corresponding to the sensor signal jumping again when the sensor leaves the wafer when the wafer is placed obliquely in the two layers of tooth grooves corresponding to the first height value and the second height value of the standard wafer boat.

[0079] That is, see Appendix Figure 4 As shown, Figure 4 The placement part of the middle dotted line is an abnormal placement part. After a standard bevel is placed on the two tooth grooves corresponding to the first height value and the second height value of the standard wafer boat (solid line placement part), the third height value is the height value when the sensor senses the standard bevel wafer and causes the sensor signal to jump, and the fourth height value is the height value when the sensor leaves the standard bevel wafer and causes the sensor signal to jump. The third height value and the fourth height value are acquired and stored in advance, and are the height values ​​of the ideal bevel state.

[0080] The fourth threshold is nλ*ξ, where n∈(0, 1], illustratively, n=0.5, and the fourth threshold is 0.5λ*ξ. When the absolute value of the difference between the first height value and the third height value is ≥ the fourth threshold, it means that the lower part of the bevel is too far away from the layer, which exceeds the tolerance of the bevel in the corresponding layer in the standard wafer boat, and therefore the tooth groove corresponding to the first height value must be abnormal. Similarly, when the absolute value of the difference between the second height value and the fourth height value is ≥ the fourth threshold, it means that the upper part of the bevel is too far away from the layer, which exceeds the tolerance of the bevel in the corresponding layer in the standard wafer boat, and therefore the tooth groove corresponding to the second height must be abnormal.

[0081] Exemplarily, the tooth groove number corresponding to the tooth groove where the lower half of the inclined plate is located is N, and the tooth groove number corresponding to the tooth groove where the upper half is located is N+1. When the absolute value of the difference between the first height value and the third height value of the Nth layer is less than 0.5λ*ξ, the layer where the lower half of the inclined plate is located is normal, that is, the tooth groove of the Nth layer is normal, otherwise it is abnormal. When the absolute value of the difference between the second height value and the fourth height value of the N+1th layer is ≥0.5λ*ξ, the tooth groove where the upper half of the inclined plate is located is abnormal, that is, the tooth groove of the N+1th layer is abnormal, otherwise it is normal.

[0082] In one embodiment, step S5, determining the wafer state and whether the tooth groove is abnormal based on the range of the sensing length, further includes:

[0083] S521, when the sensing length is greater than the fifth threshold value and less than the sixth threshold value, the wafer is a single piece and the tooth groove where the wafer is located makes the wafer tilted. At this time, the wafer and the tooth groove refer to the attached Figure 5 shown.

[0084] The fifth threshold is d+δ, and the sixth threshold is 2d, where δ is the sum of the processing error of the tooth groove and the processing error of the wafer. The normal error δ value is relatively small and will not exceed a thickness of d, such as 0.5d. When d+δ<L<2d, the sensing length exceeds the sum of the wafer, the wafer error and the tooth groove error. The wafer does not cross the tooth groove to form a bevel, but there is still a tilt phenomenon in a tooth groove.

[0085] S522: Determine whether the difference between the sensing length and the thickness of the wafer is greater than a fourth threshold.

[0086] Even if the wafer is tilted at this time, some deviation of the tooth groove is acceptable, so it is necessary to compare the deviation degree of the wafer at this time with the fourth threshold to determine the deviation degree of the corresponding tooth groove.

[0087] S523: If yes, the tooth groove where the wafer is located is abnormal.

[0088] When Ld≥0.5λ*ξ, the deviation of the tooth groove is too large, and it is judged that the tooth groove where the wafer is located is abnormal, otherwise the tooth groove where the wafer is located is normal.

[0089] Through steps S521 - S523 , while determining whether the wafer is single, it is possible to check whether the corresponding tooth groove has an abnormality.

[0090] In one embodiment, step S5, determining the wafer state and whether the tooth groove is abnormal based on the range of the sensing length, further includes:

[0091] S531, when the sensing length is greater than or equal to the sixth threshold and less than or equal to the seventh threshold, the first height value is compared with the fifth height value. The fifth height value is the height value corresponding to the sensor signal jumping when the sensor senses the wafer and sets the wafer in the tooth groove corresponding to the first height value of the standard wafer boat.

[0092] The sixth threshold is 2d, the seventh threshold is 2d+2δ, and when 2d≤L≤2d+2δ, the scanned wafer may be a stacked wafer or the wafer may be skewed due to tooth groove abnormality. Therefore, it is necessary to compare the first height value with the fifth height value for further judgment.

[0093] S532: If the first height value is equal to the fifth height value, the wafer is a stacked wafer; if the first height value is not equal to the fifth height value, the tooth groove corresponding to the first height value is abnormal.

[0094] Because if the wafer is stacked, the wafer is not tilted, and the first height value and the fifth height value are equal. If there is an abnormality in the tooth groove, the wafer will tilt, and the first height value and the fifth height value are not equal.

[0095] Wafers placed on uneven tooth grooves will tilt slightly, and the wafers are easily judged as stacked when detected by sensors. Through steps S531-S532, wafer tilt caused by the tooth grooves and stacking are distinguished, avoiding the situation where wafer tilt caused by wafer boat deformation is misjudged as stacking, thereby improving detection accuracy and timely discovering problems with the wafer boat.

[0096] In one embodiment, step S5, determining the state of the wafer and the state of the tooth groove based on the range of the sensing length, further includes:

[0097] S541. When the sensing length is greater than or equal to the thickness of the wafer and less than or equal to the fifth threshold, the wafer is a single piece and the tooth grooves corresponding to the wafer are normal.

[0098] The fifth threshold is d+δ. When d≤L≤d+δ, the wafer is within the allowable error range of processing. At this time, it can be determined that the wafer is a single piece and the corresponding tooth groove is normal.

[0099] In this embodiment, a sensor determines the single, stacked and oblique states of the wafer by acquiring the first height value and the second height value of each wafer during the process of scanning the wafer boat in the up and down directions. It can also determine whether there are abnormalities in the tooth grooves of the wafer boat and accurately find the abnormal tooth grooves.

[0100] When all wafers in the wafer boat are inspected, the movement of the fork during transport can be compensated or the wafer position can be corrected according to the inspection structure to ensure that the fork can accurately transport the wafer and avoid wafer damage.

[0101] The present invention also discloses a wafer inspection device, see the attached Figure 7 As shown, the wafer detection device includes a fork, on which a sensor is arranged. The sensor sequentially scans and detects the wafers in the wafer boat in a first direction. The detection device also includes a controller, which adopts the above-mentioned wafer detection method.

[0102] The slice fork is a single-piece slice fork or a multi-piece slice fork controlled in an integrated manner.

[0103] The present invention also discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned wafer detection method are implemented.

[0104] Based on such understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing related hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of each of the above-mentioned method embodiments when executed by a processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0105] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A wafer detection method, characterized in that: Used for detecting the state of a wafer boat and wafers in the wafer boat, the wafer states include single wafer, oblique wafer and stacked wafer, the wafer boat includes a plurality of tooth grooves arranged along a first direction for placing the wafers, and the detection method includes: Scan and detect all the wafers in the wafer boat in sequence in a first direction by using a sensor on the wafer fork; Acquire a first height value when the sensor detects each wafer and a second height value when the sensor leaves the wafer; Acquire the tooth groove number corresponding to the first height value and the second height value by matching; Calculate a sensing length of the wafer according to the first height value and the second height value; Determining whether the wafer state and the tooth groove are abnormal based on the range of the sensing length specifically includes: When the sensing length is greater than a first threshold, the wafer is a bevel wafer; Compare the sensing length with the first threshold, the second threshold and the third threshold, and determine whether there is an abnormal tooth groove in the area where the inclined sheet is located according to the comparison result; When an abnormal tooth groove exists in the area where the inclined piece is located, the tooth groove number of the abnormal tooth groove is determined according to the deviation degree between the first height value and the second height value.

2. The wafer detection method according to claim 1, characterized in that: Comparing the sensing length with the first threshold, the second threshold, and the third threshold, and judging whether there is an abnormal tooth groove in the area where the inclined piece is located according to the comparison result specifically includes: When the sensing length is greater than the second threshold, or the sensing length is greater than the first threshold and less than the third threshold, the abnormal tooth groove exists in the area where the inclined piece is located.

3. The wafer detection method according to claim 1, characterized in that: Determining the tooth groove number of the abnormal tooth groove according to the deviation degree between the first height value and the second height value specifically includes: Compare the first height value and the second height value with the third height value and the fourth height value respectively, and when the absolute value of the difference between the first height value and the third height value and / or the absolute value of the difference between the second height value and the fourth height value is greater than or equal to a fourth threshold, the tooth groove number corresponding to the first height value and / or the second height value is abnormal; The third height value is the height value corresponding to a jump in the sensor signal caused by the sensor sensing the wafer when the wafer is placed obliquely in the two layers of the tooth grooves corresponding to the first height value and the second height value of the standard wafer boat, and the fourth height value is the height value corresponding to a jump again caused by the sensor leaving the wafer when the wafer is placed obliquely in the two layers of the tooth grooves corresponding to the first height value and the second height value of the standard wafer boat.

4. The wafer detection method according to claim 1, characterized in that: Based on the range of the sensing length, determining the state of the wafer and whether the tooth groove is abnormal, further comprising: When the sensing length is greater than a fifth threshold value and less than a sixth threshold value, the wafer is a single piece and the tooth groove where the wafer is located causes the wafer to tilt; Determining whether a difference between the sensing length and the thickness of the wafer is greater than a fourth threshold; If so, the tooth groove where the wafer is located is abnormal.

5. The wafer detection method according to claim 1, characterized in that: Based on the range of the sensing length, determining the state of the wafer and whether the tooth groove is abnormal, further comprising: When the sensing length is greater than or equal to the sixth threshold value and less than or equal to the seventh threshold value, the first height value is compared with the fifth height value, and the fifth height value is the height value corresponding to the sensor signal jumping when the sensor senses the wafer and the wafer is placed in the tooth groove corresponding to the first height value of the standard wafer boat; If the first height value is equal to the fifth height value, the wafer is a stacked wafer; if the first height value is not equal to the fifth height value, the tooth groove corresponding to the first height value is abnormal.

6. The wafer detection method according to claim 1, characterized in that: Based on the range of the sensing length, determining the state of the wafer and the state of the tooth groove also includes: When the sensing length is greater than or equal to the thickness of the wafer and less than or equal to a fifth threshold, the wafer is a single piece, and the tooth grooves corresponding to the wafer are normal.

7. The wafer detection method according to any one of claims 1 to 6, characterized in that: Acquiring the tooth groove number corresponding to the first height value and the second height value by matching specifically includes: Acquire a data set when a single wafer is inserted into each layer of the tooth slot in a standard wafer boat, the data set including the tooth slot number and the corresponding area height range; The data set is traversed to find the area height range corresponding to the first height value and the second height value to determine the tooth groove number.

8. The wafer detection method according to any one of claims 1 to 6, characterized in that: The sensing length is the absolute value of the difference between the first height value and the second height value.

9. A wafer inspection device, characterized in that: It comprises a fork, on which a sensor is arranged, and the sensor sequentially scans and detects the wafers in the wafer boat in a first direction, and the detection equipment adopts the wafer detection method according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the wafer detection method according to any one of claims 1 to 8 are implemented.

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