Wafer crack detection device and wafer crack detection method
By combining a stage unit, a pressing unit, and a sonar probe, the problems of low accuracy and lack of quantification in wafer microcrack detection are solved, achieving efficient and accurate wafer microcrack detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XIAN ESWIN MATERIAL TECHNOLOGY CO LTD
- Filing Date
- 2022-12-26
- Publication Date
- 2026-05-29
AI Technical Summary
Existing technologies for detecting microcracks in wafers have low accuracy and cannot be quantified, while manual detection methods have poor reliability and low detection rates.
The wafer microcrack detection device, consisting of a stage unit, a pressing unit, and a control unit, controls the pressing pressure, number of times, and time through pressing parameters, and combines sonar probes to detect acoustic wave data to achieve automated detection.
It improves the accuracy and detection rate of wafer microcrack detection, realizes the quantitative detection of wafer microcracks, and reduces damage to wafers.
Smart Images
Figure CN115938968B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer microcrack detection device and a wafer microcrack detection method. Background Technology
[0002] In the semiconductor wafer manufacturing industry, microcracks are hidden, non-penetrating cracks that exist within the wafer. They are generally attributed to uneven internal thermal stress during crystal growth or stress damage during machining. Minor microcracks affect product quality and render the wafer unsuitable for high-end chip manufacturing. More severe microcracks typically cause breakage during the forming or polishing process, often leading to equipment malfunctions and requiring replacement of grinding discs and other spare parts, resulting in significant waste of production capacity and costs.
[0003] In related technologies, the following two methods are generally used to detect microcracks in wafers:
[0004] 1) Automatic detection method: This method uses a through-type microcrack camera to detect microcracks inside the wafer. However, this method has poor detection accuracy, and the relevant technical conditions are not yet fully mature and are still in the process of gradual improvement and verification. Moreover, it is not very effective for heavily doped products, and the equipment investment cost is relatively high. 2) Manual detection method: This method magnifies the microcrack damage inside the wafer by touching, pressing, or tapping, and then visually inspects the wafer surface for abnormalities such as bulges, fine cracks, and surface roughness to determine whether there are microcracks inside the wafer. However, the operation methods of this method are difficult to quantify, especially the wafer pressure value during pressing and tapping, which cannot be quantified. The overall detection results lack data support, have poor reliability, and a low detection rate. Summary of the Invention
[0005] This disclosure provides a wafer microcrack detection device and method, which can solve the problem that the existing manual wafer inspection method cannot quantitatively amplify wafer microcrack damage, improve detection accuracy, and achieve a high detection rate.
[0006] The technical solutions provided in this disclosure are as follows:
[0007] In a first aspect, embodiments of this disclosure provide a wafer microcrack detection device, comprising:
[0008] Stage unit used to support the wafer under test;
[0009] A pressing unit for performing a pressing action on the wafer under test on the stage unit, the pressing unit being located above the stage unit, the pressing unit including a pressing rod and a driving member, the pressing rod being axially perpendicular to the stage unit and movable along its own axis, the pressing unit having a pressing head at one end axially close to the stage unit, and the driving member being connected to the end of the pressing unit axially away from the stage unit; and
[0010] A control unit for controlling the working state of the pressing unit according to preset pressing parameters, wherein the preset pressing parameters include at least one of the following: pressing force, number of pressings, pressing position, and pressing time.
[0011] For example, the preset pressure parameters include pressure parameters input by the user and / or pre-stored pressure parameters.
[0012] For example, the drive unit includes a servo electric cylinder.
[0013] For example, the control unit includes:
[0014] A pressure sensor, disposed on the pressing head, is used to detect the real-time pressure value of the pressing head pressed onto the wafer under test; and
[0015] The controller is electrically connected to the pressure sensor and is used to control the working state of the drive unit based on the real-time pressure value fed back by the pressure sensor and the pressing force value in the preset pressure parameters.
[0016] For example, the stage unit includes:
[0017] The stage body for holding the wafer under test; and
[0018] A rotating mechanism is connected to the platform body and is capable of driving the platform body to perform circular motion around an axis perpendicular to the platform body.
[0019] For example, the control unit is also connected to the rotating mechanism for controlling the working state of the rotating mechanism according to preset pressing parameters.
[0020] For example, the driving component includes a high-frequency pulse vibration motor capable of driving the pressing rod to perform high-frequency pulse vibration;
[0021] The pressing head is also equipped with a sonar probe, which is used to detect real-time vibration sound wave data of the surface of the wafer under test.
[0022] The control unit further includes:
[0023] A memory used to pre-store normal sound wave data;
[0024] An acoustic wave analyzer, connected to the sonar probe and the memory, is used to compare the real-time vibration acoustic wave data with the normal acoustic wave data to determine the microcrack result of the silicon wafer under test.
[0025] Secondly, this disclosure also provides a method for detecting microcracks in a wafer, applied to the wafer microcrack detection device described above, the method comprising the following steps:
[0026] The wafer to be tested is mounted on the stage unit;
[0027] The control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer under test on the stage unit. The preset pressing parameters include at least one of the following: pressing force value, number of pressing, pressing position and pressing time.
[0028] For example, the control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer under test on the stage unit, specifically including:
[0029] The user inputs the pressing parameters into the controller, or the pressing parameters are pre-stored in the controller;
[0030] Adjust the position of the wafer under test so that the first test position of the wafer under test is directly below the pressing head;
[0031] The controller controls the drive unit to start, so that the pressing rod descends and presses on the first test position;
[0032] The pressure sensor feeds back the real-time pressure value of the pressing head to the controller. When the real-time pressure value reaches the pressing force value in the preset pressing parameters, the controller controls the pressing rod to stop descending and, after holding the pressing time within the preset pressing parameters, controls the pressing rod to rise to complete one pressing action.
[0033] Repeat the above pressing action to complete multiple pressing actions on the first test location according to the number of pressing actions.
[0034] For example, the control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer under test on the stage unit, specifically including:
[0035] After multiple pressing actions are completed at the first test position, the stage body is rotated by the rotating mechanism to adjust the position of the test wafer so that the second test position of the test wafer is located directly below the pressing head.
[0036] Repeat the pressing action described above to perform multiple pressing actions on the second test location.
[0037] For example, when the control unit controls the working state of the pressing unit according to the preset pressing parameters to perform a pressing action on the wafer under test on the stage unit, the control unit controls the driving member to drive the pressing member to perform high-frequency pulse vibration on the surface of the wafer under test;
[0038] The sonar probe is used to detect real-time vibration acoustic wave data on the surface of the wafer under test.
[0039] The real-time vibration acoustic data is compared with the normal acoustic data using the acoustic analyzer to determine the microcrack result of the silicon wafer under test.
[0040] The beneficial effects of the embodiments disclosed herein are as follows:
[0041] The wafer microcrack detection device and method provided in this disclosure can quantify the pressing action, such as the pressing force, the number of pressings, and the pressing time, at a designated location on the wafer to be tested, thus solving the problem that the pressure cannot be quantified in the manual tapping detection method in the prior art. Attached Figure Description
[0042] Figure 1 This is a schematic diagram of the structure of the wafer microcrack detection device provided in the embodiments of this disclosure;
[0043] Figure 2 This is a flowchart illustrating the wafer microcrack detection method provided in the embodiments of this disclosure. Detailed Implementation
[0044] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.
[0045] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.
[0046] like Figure 1 As shown, the wafer microcrack detection device provided in this embodiment includes:
[0047] Stage unit 20 for supporting the wafer 10 under test;
[0048] A pressing unit 30 is used to perform a pressing action on the wafer 10 under test on the stage unit 20. The pressing unit 30 is located above the stage unit 20. The pressing unit 30 includes a pressing rod 31 and a driving member 32. The pressing rod 31 is axially perpendicular to the stage unit 20 and movable along its own axis. The pressing unit 30 has a pressing head 311 at one end of its axis near the stage unit 20. The driving member 32 is connected to the end of the pressing unit 30 axially away from the stage unit 20.
[0049] A control unit for controlling the working state of the pressing unit 30 according to preset pressing parameters, wherein the preset pressing parameters include at least one of the following: pressing force, number of pressings, pressing position, and pressing time.
[0050] In the above scheme, when the wafer microcrack detection device performs wafer microcrack detection, the wafer to be tested 10 can be supported on the stage unit 20. The control unit can control the pressing unit 30 to perform pressing action on the wafer to be tested 10 by preset pressing parameters, so that parameters such as pressing force, pressing number and pressing time at a specified position of the wafer to be tested 10 can be quantified, solving the problem that the pressure cannot be quantified in the manual tapping detection method in the prior art. Compared with the poor accuracy of camera detection in related technologies, it can improve detection accuracy and has a high detection rate.
[0051] As shown in the figure, in some exemplary embodiments, the preset pressing parameters include pressing parameters input by the user and / or pre-stored pressing parameters. That is, the preset pressing parameters can be pressing parameters input by the operator according to the actual testing needs each time a wafer microcrack detection is performed (for example, a display screen 70 can be set on the device to display the pressing parameters input by the user), or they can be pre-stored pressing parameters.
[0052] In some embodiments, the drive element 32 includes a servo electric cylinder. Using a servo electric cylinder to drive the pressing rod 31 allows for the slow application of pressure to the wafer 10 under test, minimizing damage to the wafer surface. It is understood that the drive element 32 is not limited to a servo electric cylinder. For example, the drive element 32 could also be a hydraulic cylinder, etc.
[0053] For example, such as Figure 1 As shown, the control unit includes:
[0054] Pressure sensor 41, disposed on the pressing head 311, is used to detect the real-time pressure value of the pressing head 311 pressing onto the wafer 10 under test; and
[0055] The controller 42 is electrically connected to the pressure sensor 41 and is used to control the working state of the drive unit based on the real-time pressure value fed back by the pressure sensor 41 and the pressing force value in the preset pressure parameters.
[0056] By employing the above solution, and by installing the pressure sensor 41 on the pressing head 311, the pressing force of the pressing head 311 can be detected in real time, so as to accurately control the pressing force for different types of silicon wafers. Furthermore, an elastic pad can also be provided on the pressing head 311 to avoid damage to the wafer surface.
[0057] In addition, for example, Figure 1 As shown, the stage unit 20 includes:
[0058] The stage body 21 for holding the wafer 10 under test; and
[0059] A rotating mechanism 22 is connected to the platform body 21 and is capable of driving the platform body 21 to perform circular motion around an axis perpendicular to the platform body 21.
[0060] Using the above scheme, the stage body 21 can perform circumferential motion under the drive of the rotating mechanism 22. In this way, when the wafer 10 to be tested is placed on the stage body 21, by rotating the stage body 21, a certain position of the wafer 10 to be tested can be located directly below the pressing head 311, which is the current test position. After the pressing action of the current test position is completed, the stage body 21 can be rotated by a predetermined angle so that the next test position of the wafer 10 to be tested is located directly below the pressing head 311 for pressing detection of the next test position, until all test positions have been pressed and detected.
[0061] The control unit is also connected to the rotating mechanism 22 and is used to control the working state of the rotating mechanism 22 according to preset pressing parameters.
[0062] Furthermore, in one exemplary embodiment, the driving element 32 includes a high-frequency pulse vibration motor capable of driving the pressing rod 31 to perform high-frequency pulse vibration; such as Figure 1 As shown, the pressing head 311 is also equipped with a sonar probe 33, which is used to detect real-time vibration sound wave data on the surface of the wafer 10 under test.
[0063] The control unit further includes:
[0064] Memory, used to pre-store normal sound wave data; and
[0065] An acoustic wave analyzer, connected to the sonar probe 33 and the memory, is used to compare the real-time vibration acoustic wave data with the normal acoustic wave data to determine the microcrack result of the silicon wafer under test.
[0066] Using the above scheme, the control unit sends a high-frequency pulse command to the drive component 32 to control the pressing rod 31 to vibrate the surface of the wafer 10 to be tested at high frequency. Since normal wafers and microcracked wafers have different absorption degrees of sound waves, the microcrack situation of the wafer can be identified by analyzing the difference in sound waves, thus realizing the automatic detection function and solving the problem of low efficiency of manual detection.
[0067] Furthermore, as a specific embodiment, such as Figure 1 As shown, the overall architecture of the wafer microcrack detection device may also include: a base 50 and a body 60, wherein the stage unit 20 may be disposed on the base 50, and the body 60 is fixed on the base 50. As shown, the pressing rod 31 and the driving component 32 may be installed on the body 60, and the body 60 may include a transparent protective cover 61 to facilitate maintenance of the pressing unit 30, etc.
[0068] Secondly, this disclosure also provides a method for detecting microcracks in wafers, applied to the wafer microcrack detection device provided in this disclosure, such as... Figure 2 As shown, the method includes the following steps:
[0069] Step S01: Place the wafer 10 to be tested onto the stage unit 20;
[0070] Step S02: The control unit controls the working state of the pressing unit 30 according to the preset pressing parameters to perform a pressing action on the wafer 10 to be tested on the stage unit 20. The preset pressing parameters include at least one of the following: pressing force value, number of pressing, pressing position and pressing time.
[0071] For example, step S02 above specifically includes:
[0072] Step S021: The user inputs pressing parameters into the controller 42, or the controller 42 stores pressing parameters in advance;
[0073] Step S022: Adjust the position of the wafer to be tested 10 so that the first test position of the wafer to be tested 10 is directly below the pressing head 311;
[0074] Step S023: The controller 42 controls the drive component 32 to start, so that the pressing rod 31 descends and presses on the first test position;
[0075] Step S024: The pressure sensor 41 feeds back the real-time pressure value of the pressing head 311 to the controller 42. When the real-time pressure value reaches the pressing force value in the preset pressing parameters, the pressing rod 31 is controlled to stop descending and stay within the pressing time in the preset pressing parameters before the pressing rod 31 is controlled to rise to complete one pressing action.
[0076] Step S025: Repeat the above pressing action (i.e., steps S023 to S024) to complete multiple pressing actions on the first test position according to the number of pressing actions.
[0077] For example, step S01 above specifically includes:
[0078] Step S026: After completing multiple pressing actions on the first test position, the stage body 21 is rotated by the rotating mechanism 22 to adjust the position of the test wafer 10 so that the second test position of the test wafer 10 is located directly below the pressing head 311.
[0079] Step S027: Repeat the above pressing action (i.e., steps S023 to S024) to complete multiple pressing actions on the second test position.
[0080] For example, step S02 specifically includes:
[0081] When the control unit controls the working state of the pressing unit 30 according to the preset pressing parameters to perform a pressing action on the wafer 10 to be tested on the stage unit 20, the control unit controls the driving member 32 to drive the pressing member to perform high-frequency pulse vibration on the surface of the wafer 10 to be tested.
[0082] The real-time vibration acoustic wave data of the surface of the wafer 10 under test is detected by the sonar probe 33.
[0083] The acoustic wave analyzer 44 compares the real-time vibration acoustic wave data with the normal acoustic wave data to determine the microcrack result of the silicon wafer under test.
[0084] The following points need to be explained:
[0085] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.
[0086] (2) For clarity, the thickness of layers or regions is enlarged or reduced in the drawings used to describe embodiments of the present disclosure, i.e., these drawings are not drawn to actual scale. It will be understood that when an element such as a layer, film, region or substrate is referred to as being “above” or “below” another element, the element may be “directly” located “above” or “below” the other element or there may be intermediate elements.
[0087] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.
[0088] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure shall be determined by the scope of the claims.
Claims
1. A wafer microcrack detection device, characterized in that, include: Stage unit used to support the wafer under test; A pressing unit for performing a pressing action on the wafer under test on the stage unit, the pressing unit being located above the stage unit, the pressing unit including a pressing rod and a driving member, the pressing rod being axially perpendicular to the stage unit and movable along its own axis, the pressing unit having a pressing head at one end axially close to the stage unit, and the driving member being connected to the end of the pressing unit axially away from the stage unit; and A control unit for controlling the working state of the pressing unit according to preset pressing parameters, wherein the preset pressing parameters include at least one of the following: pressing force, number of pressings, pressing position, and pressing time; The driving component includes a high-frequency pulse vibration motor capable of driving the pressing rod to perform high-frequency pulse vibration; the pressing head is also equipped with a sonar probe, which is used to detect real-time vibration sound wave data of the surface of the wafer under test. The control unit further includes: A memory used to pre-store normal sound wave data; An acoustic wave analyzer is connected to the sonar probe and the memory, respectively, and is used to compare the real-time vibration acoustic wave data with the normal acoustic wave data to determine the microcrack result of the wafer under test. When the control unit controls the working state of the pressing unit according to the preset pressing parameters to perform a pressing action on the wafer under test on the stage unit, the control unit controls the driving component to drive the pressing unit to perform high-frequency pulse vibration on the surface of the wafer under test.
2. The wafer microcrack detection device according to claim 1, characterized in that, The preset pressure parameters include pressure parameters input by the user and / or pre-stored pressure parameters.
3. The wafer microcrack detection device according to claim 1, characterized in that, The control unit includes: A pressure sensor, disposed on the pressing head, is used to detect the real-time pressure value of the pressing head pressed onto the wafer under test; and The controller is electrically connected to the pressure sensor and is used to control the working state of the drive component based on the real-time pressure value fed back by the pressure sensor and the pressing force value in the preset pressing parameters.
4. The wafer microcrack detection device according to claim 1, characterized in that, The platform unit includes: The stage body for holding the wafer under test; and A rotating mechanism is connected to the platform body and is capable of driving the platform body to perform circular motion around an axis perpendicular to the platform body. The control unit is also connected to the rotating mechanism and is used to control the working state of the rotating mechanism according to preset pressing parameters.
5. A method for detecting microcracks in a wafer, characterized in that, The method, applied to the wafer microcrack detection apparatus as described in any one of claims 1 to 4, comprises the following steps: The wafer to be tested is mounted on the stage unit; The control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer under test on the stage unit. The preset pressing parameters include at least one of the following: pressing force value, number of pressing, pressing position and pressing time. When the control unit controls the working state of the pressing unit according to the preset pressing parameters to perform a pressing action on the wafer under test on the stage unit, the control unit controls the driving component to drive the pressing unit to perform high-frequency pulse vibration on the surface of the wafer under test; The sonar probe is used to detect real-time vibration acoustic wave data on the surface of the wafer under test. The real-time vibration acoustic data is compared with the normal acoustic data using the acoustic analyzer to determine the microcrack result of the wafer under test.
6. The wafer microcrack detection method according to claim 5, characterized in that, When applied to the wafer microcrack detection device as described in claim 3, the control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer to be tested on the stage unit, specifically including: The user inputs the pressing parameters into the controller, or the pressing parameters are pre-stored in the controller; Adjust the position of the wafer under test so that the first test position of the wafer under test is directly below the pressing head; The controller controls the drive unit to start, so that the pressing rod descends and presses against the first test position; The pressure sensor feeds back the real-time pressure value of the pressing head to the controller. When the real-time pressure value reaches the pressing force value in the preset pressing parameters, the controller controls the pressing rod to stop descending and, after holding the pressing time within the preset pressing parameters, controls the pressing rod to rise to complete one pressing action. Repeat the above pressing action to complete multiple pressing actions on the first test location according to the number of pressing actions.
7. The wafer microcrack detection method according to claim 5, characterized in that, When applied to the wafer microcrack detection device as described in claim 4, the control unit controls the working state of the pressing unit according to preset pressing parameters to perform a pressing action on the wafer to be tested on the stage unit, specifically including: After multiple pressing actions are completed at the first test position of the wafer under test, the stage body is rotated by the rotating mechanism to adjust the position of the wafer under test so that the second test position of the wafer under test is directly below the pressing head. Repeat the pressing action described above to perform multiple pressing actions on the second test location.