Loading port device, front-end loading device, wafer processing equipment and detection method

Abstract

The invention provides a loading port device, a front-end loading device, wafer processing equipment and a detection method. The load port device includes: a main body; the loading platform horizontally protrudes from the main body and is used for placing a wafer box, and the wafer box is constructed to be used for stacking wafers at intervals in the vertical direction; the detection mechanism is movably installed on the main body and can move in the vertical direction to sequentially detect the wafers in the wafer box, and the detection mechanism comprises a warping detector and an analyzer in communication connection with the warping detector; the warpage detector is configured to send a warpage detection signal to the analyzer, and the warpage detection signal increases as the horizontal distance from the warpage detector to the wafer decreases; the analyzer is configured to determine warpage information of the wafer based on the warpage detection signal and a vertical displacement of the warpage detector. According to the technical scheme provided by the invention, the warping condition of the wafer can be quickly and accurately judged, and accurate wafer information is provided for a subsequent wafer transmission process and a subsequent wafer processing process.

Description

[0001] This application is a divisional application of the invention patent filed on February 14, 2025, with application number 2025101622950, ​​entitled "Loading Port Device, Front-End Loading Device, Wafer Processing Equipment and Testing Method". Technical Field

[0002] This application relates to the field of wafer processing technology, specifically to a loading port device, a front-end loading device, wafer processing equipment, and a testing method. Background Technology

[0003] Load ports are essential components in semiconductor equipment, providing an interactive carrier for the transfer of wafers between different processing stations. A robotic arm transfers wafers from the wafer cassette on the load port to the processing unit on the processing station. However, during actual processing, wafers may warp due to internal stress or other reasons, or the bonding wafer formed after bonding two wafers may warp. This can cause a mismatch between the wafer's position in the wafer cassette and the robotic arm's pick-up point, leading to wafer breakage due to collisions during pick-up or unstable clamping during transfer. This necessitates stopping the wafer processing equipment for cleaning and repositioning the robotic arm, impacting the equipment's effective operating time, reducing processing efficiency, and increasing maintenance costs. Summary of the Invention

[0004] This application provides a loading port device, a front-end loading device, a wafer processing equipment, and a testing method to solve or alleviate at least some of the problems mentioned above.

[0005] According to one aspect of this application, a loading port device is provided for a wafer processing apparatus, the loading port device comprising: a main body; a loading stage horizontally protruding from the main body for placing a wafer cassette, the wafer cassette being configured to stack wafers at intervals in a vertical direction; and a detection mechanism movably mounted to the main body and movable in a vertical direction to sequentially detect wafers in the wafer cassette, the detection mechanism including a warpage detector and an analyzer communicatively connected to the warpage detector; the warpage detector being configured to send a warpage detection signal to the analyzer, the warpage detection signal increasing as the horizontal distance from the warpage detector to the wafer decreases; and the analyzer being configured to determine warpage information of the wafer based on the warpage detection signal and the vertical displacement of the warpage detector.

[0006] Optionally or alternatively, the analyzer can generate a waveform image of the warpage detection signal as the warpage detector changes with the vertical displacement of the warpage detector, and determine the warpage information of the wafer based on the shape of the waveform image.

[0007] Optionally or alternatively, the warp information includes the degree of warp and / or the direction of warp.

[0008] Optionally or alternatively, the analyzer determines that the corresponding wafer is a non-warped wafer based on the convex rectangular waves in the waveform image.

[0009] Optionally or alternatively, the analyzer determines that the corresponding wafer is a warped wafer based on the convex waveform in the waveform image having a plateau region and a curved region continuous with the plateau region.

[0010] Optionally or alternatively, the analyzer determines that the warpage direction of the corresponding wafer is opposite to the vertical displacement direction of the warpage detector based on the fact that the curved region is downstream of the plateau region and the curved region gradually descends in the vertical displacement direction of the warpage detector.

[0011] Optionally or alternatively, the analyzer determines that the warpage direction of the corresponding wafer is the same as the vertical displacement direction of the warpage detector, based on the fact that the curved region is located upstream of the platform region and the curved region gradually rises in the vertical displacement direction of the warpage detector.

[0012] Optionally or alternatively, the analyzer determines the warpage of the corresponding wafer based on the total width of the platform region and the continuous curve region in the vertical displacement direction of the warpage detector. When the warpage direction is downward, the absolute value of the warpage output by the analyzer based on the same total width is lower than that when the warpage direction is upward.

[0013] Optionally or alternatively, the analyzer is further configured to determine the warpage smoothness of the wafer based on the curvature of the curved region, to determine the warpage smoothness as smooth when the curvature of the curved region is the same or changes continuously, and to determine the warpage smoothness as non-smooth when there is an abrupt change in the curvature of the curved region.

[0014] Optionally or alternatively, the analyzer is also configured to determine the wafer thickness based on the width of the plateau region of the convex waveform in the waveform image.

[0015] Optionally or alternatively, the analyzer is also configured to determine the wafer placement state based on the shape of the waveform image, the placement state including monolithic, stacked, and cross-slot states.

[0016] Optionally or alternatively, the wafer cassette has a plurality of horizontal slots arranged vertically for placing wafers, and the analyzer has a preset interval matching the vertical dimension of the horizontal slots; the analyzer determines the placement state as a single-wafer state based on the width of the protruding waveform in the waveform image being less than the preset interval and the width of the plateau region of the protruding waveform in the waveform image being less than or equal to a wafer thickness threshold; and / or the analyzer determines the placement state as a stacked state based on the width of the protruding waveform in the waveform image being less than the preset interval and the width of the plateau region of the protruding waveform in the waveform image being greater than the wafer thickness threshold; and / or the analyzer determines the placement state as a cross-slot state based on the width of the protruding waveform in the waveform image exceeding the preset interval.

[0017] Optionally or alternatively, the detection mechanism includes two or more warp detectors arranged at intervals, and the analyzer determines warp information of the wafer in the arrangement direction of the two or more warp detectors and in a direction perpendicular to the arrangement direction by analyzing the waveform images of the two or more warp detectors.

[0018] Optionally or alternatively, the warp detector is an infrared sensor.

[0019] Optionally or alternatively, the wafer cassette has a plurality of horizontal slots arranged in a vertical direction for placing wafers; the detection mechanism further includes a state detector configured to detect the placement state of the wafers in the horizontal slots, the placement state including monolithic state, stacked state, and cross-slot state.

[0020] Optionally or alternatively, the state detector is a through-beam sensor, which includes a transmitter and a receiver arranged horizontally at intervals, the receiver receiving through-beam light emitted by the transmitter; during wafer inspection, the state detector extends at least partially into the wafer cassette so that as the inspection mechanism moves vertically, the wafer in the wafer cassette passes between the transmitter and the receiver to block the through-beam light, and the through-beam sensor determines the placement state based on the time during which the receiver does not receive the through-beam light or the distance traveled during which the receiver does not receive the through-beam light.

[0021] Optionally or alternatively, the loading port device further includes a display communicatively connected to the inspection mechanism, the display being configured to receive and display wafer warpage information and placement status information.

[0022] Optionally or alternatively, the wafer cassette has a plurality of horizontal slots arranged in a vertical direction for placing wafers, the horizontal slots extending from the sidewall of the wafer cassette into the interior of the wafer cassette; the detection mechanism further includes a vision detector disposed toward the sidewall of the wafer cassette; the vision detector is configured to detect the edge of the wafer at the horizontal slot and identify the horizontal distance between the edge of the wafer and the sidewall of the wafer cassette to determine wafer warpage information.

[0023] Optionally or alternatively, identifying the horizontal distance between the edge of the wafer and the sidewall of the wafer cassette includes: the vision detector constructing a first virtual scale extending horizontally inward from the inner surface of the sidewall of the wafer cassette in its detection field of view, and reading the scale corresponding to the edge of the wafer to determine the horizontal distance; the vision detector is configured to determine that the corresponding wafer is a warped wafer when the horizontal distance is greater than a first distance threshold.

[0024] Optionally or alternatively, the vision detector is further configured to identify the vertical distance between the edge of the wafer and the horizontal slot, including: the vision detector constructs a second virtual scale extending vertically upward from the upper surface of the horizontal slot in its detection field of view, and reads the scale corresponding to the edge of the wafer to determine the vertical distance; the vision detector is configured to: determine that the warping direction of the corresponding wafer is upward warping when the horizontal distance is greater than a first distance threshold and the vertical distance is greater than a second distance threshold; and determine that the warping direction of the corresponding wafer is downward warping when the horizontal distance is greater than the first distance threshold and the vertical distance is not greater than the second distance threshold.

[0025] Optionally or alternatively, identifying the horizontal distance between the edge of the wafer and the sidewall of the wafer cassette includes: the visual detector identifying whether a wafer exists at a first distance threshold horizontally from the inner surface of the sidewall of the wafer cassette; if no wafer exists, it is determined that the horizontal distance between the wafer and the inner surface of the sidewall of the wafer cassette exceeds the first distance threshold, thereby determining that the corresponding wafer is a warped wafer.

[0026] Optionally or alternatively, the main body is configured with a window through which the detection mechanism detects wafers in the wafer cassette; the loading port device further includes a door opener mounted to the main body, the door opener being configured to open a movable door of the wafer cassette facing the window and move the movable door to expose the wafers in the wafer cassette toward the loading port device.

[0027] According to another aspect of this application, a front-end loading device is provided for a wafer processing apparatus, the front-end loading device comprising: a loading port device according to the foregoing aspect; a wafer cassette movably placed on a loading stage of the loading port device, the wafer cassette being configured to stack wafers at intervals in a vertical direction; and a front-end robot configured to pick up wafers from the wafer cassette or place wafers into the wafer cassette.

[0028] According to another aspect of this application, a front-end loading device and a wafer processing apparatus are provided. The wafer processing apparatus includes: the front-end loading device as described in the foregoing aspect; a wafer processing unit; and a wafer transfer device configured to transfer a wafer from the front-end loading device to the wafer processing unit for wafer processing.

[0029] According to another aspect of this application, a wafer inspection method is provided for a loading port device as described in the foregoing aspect, the method comprising: opening a movable door of a wafer cassette to expose a wafer in the wafer cassette toward an inspection mechanism; controlling the inspection mechanism to move vertically to sequentially inspect the wafers in the wafer cassette; and outputting the inspected wafer information.

[0030] Optionally or alternatively, controlling the detection mechanism to move vertically to sequentially detect wafers in the wafer cassette includes detecting wafer warpage information via a warpage detector.

[0031] Optionally or alternatively, controlling the detection mechanism to move vertically to sequentially detect the wafers in the wafer cassette includes: detecting the placement state of the wafers via a warp detector and / or detecting the placement state of the wafers via a state detector.

[0032] Optionally or alternatively, the wafer-picking position of the front-end robot used to pick up the wafer from the wafer cassette is adjusted based on the wafer warp information.

[0033] According to another aspect of this application, a computer storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the method described in the foregoing aspects.

[0034] According to the loading port device, front-end loading device, wafer processing equipment, and detection method of this application, by setting up a detection mechanism, automated detection of wafer warpage is achieved, avoiding errors in human visual inspection. It can quickly and accurately determine the wafer warpage condition, providing accurate wafer information for subsequent wafer transport and wafer processing processes. This facilitates timely and adaptive adjustment of the corresponding operating parameters of the wafer transport unit and wafer processing unit, or timely unloading of wafers with excessive warpage or other defects that do not meet processing requirements. This avoids wafer breakage or damage to the wafer processing equipment during processing, improves the processing efficiency of the wafer processing equipment, and increases the yield and service life of the wafer processing equipment. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0036] Figure 1 This is a schematic diagram of a wafer processing apparatus according to one embodiment of this application;

[0037] Figure 2 for Figure 1 A schematic diagram of the loading port device in the figure, showing the wafer cassette;

[0038] Figure 3 for Figure 1 A schematic diagram of the loading port device in the figure, the wafer cassette is not shown;

[0039] Figure 4 for Figure 3 A schematic diagram of the loading port device from another angle;

[0040] Figure 5 A wafer cassette according to one embodiment of this application is shown, the wafer cassette being opened;

[0041] Figure 6 It shows Figure 5 Another view of the wafer cassette, shown in the figure. Figure 2 The detection mechanism of the loading port device in the middle;

[0042] Figure 7 This diagram shows a top view of the wafer inspection process.

[0043] Figure 8 for Figure 6 A schematic diagram of the wafer cassette and testing mechanism from another angle;

[0044] Figure 9 for Figure 5 A cross-sectional view at point AA in the middle wafer box;

[0045] Figure 10 This is a schematic diagram of the wafer inspection process;

[0046] Figure 11 A schematic diagram of a waveform image generated by an analyzer according to one embodiment of this application is shown;

[0047] Figure 12 A schematic diagram showing another waveform image generated by an analyzer according to one embodiment of this application is illustrated;

[0048] Figure 13 A schematic diagram showing another waveform image generated by an analyzer according to one embodiment of this application is illustrated;

[0049] Figure 14 It shows Figure 5 A schematic diagram of the wafer cell from another angle;

[0050] Figure 15 It shows Figure 14 Enlarged view of point D in the image;

[0051] Figure 16 A flowchart of a wafer inspection method according to one embodiment of this application is shown;

[0052] Figure 17 The execution was shown Figure 16 This is a flowchart of information processing in a wafer inspection method.

[0053] Figure label:

[0054] Wafer processing equipment 1; front-end loading device 10; front-end robot 101; polishing unit 20; thinning unit 30; wafer transfer unit 40; loading port device 100; main body 110; window 111; door opener 112; loading stage 120; detection mechanism 130; horizontal bar 131a; vertical bar 131b; wafer box 200; horizontal slot 210; warp detector 132; status detector 133; vision detector 134; display 140; controller 150; waveform 50; plateau area 51; curve area 52; first position P1; second position P2; first virtual scale R1; second virtual scale R2; wafer W. Detailed Implementation

[0055] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0056] In the description of this application, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0057] In addition, in the description of this application, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0058] Figure 1 This is a schematic diagram of a wafer processing apparatus 1 according to one embodiment of this application. The wafer processing apparatus 1 includes a front-end loading device 10, a wafer processing unit, and a system for transferring wafers W between the front-end loading device 10 and the wafer processing unit (see [link]). Figure 5 The wafer transfer unit 40 is included. The wafer processing unit may include a thinning unit 30 for grinding and thinning the wafer W and a polishing unit 20 for surface polishing and cleaning the wafer W. It should be understood that in other embodiments, the wafer processing unit may include only one of the thinning unit 30 or the polishing unit 20, or it may include processing units that implement other processing techniques, such as a wafer edge polishing unit or a wafer edge dicing unit.

[0059] like Figure 1-4 As shown, the front-end loading device 10 may include a loading port device 100, a wafer cassette 200 movably placed on a loading stage 120 of the loading port device 100, and a front-end robotic arm 101 for picking up or placing wafers W from or into the wafer cassette 200. The wafer cassette 200 may be a FOUP (Front Open Uniformed Pod). Specifically, as... Figure 2-4The loading port device 100 mainly includes a main body 110, a loading platform 120 protruding horizontally from the main body 110, and a detection mechanism 130 movably installed on the main body 110 (see...). Figure 4 The loading stage 120 is used to place the wafer cassette 200. The main body 110 extends vertically and is equipped with a window 111. In the vertical direction, the window 111 is located above the loading stage 120, and the opening size of the window 111 matches the size of the wafer cassette 200. The inspection mechanism 130 can inspect the wafers W in the wafer cassette 200 through the window 111, and the front-end robot 101 can enter the wafer cassette 200 through the window 111 to pick up and place wafers. "Movable placement" means that the wafer cassette 200 can be placed on the loading stage 120 of the loading port device 100, for example, to supply wafers W to be processed to the wafer processing unit; it can also be removed from the loading stage 120 of the loading port device 100, for example, to remove processed wafers W received from the wafer processing unit.

[0060] Figure 5 A wafer cassette 200 according to one embodiment of this application is shown. The wafer cassette 200 is open, and for clarity, only one wafer W is shown. The wafer cassette 200 has dimensions suitable for accommodating the wafer W, and its cavity has a plurality of horizontal slots 210 arranged vertically for stacking the wafers W at intervals in the vertical direction. Figure 5 The diagram shows horizontal slots 210 formed in the form of partitions, i.e., multiple partitions are symmetrically arranged on the inner walls of both sides of the wafer cassette 200, forming horizontal slots 210 between adjacent partitions in the vertical direction. The wafer cassette 200 has a removable movable door (not shown), which faces the loading port device 100 when the wafer cassette 200 is placed on the loading stage 120 of the loading port device 100, i.e., towards... Figure 1 On the left side of the middle. The loading port device 100 may have a door opener 112 mounted to its body 110 (see also...). Figure 3 The door opener 112 can open the movable door of the wafer box 200 and move the movable door so that the movable door avoids obstructing the wafer W, so that the wafer W is exposed toward the loading port device 100, so that the detection mechanism 130 can detect the wafer W in the wafer box 200, or so that the front-end robot arm 101 can pick up and put the wafer W.

[0061] In a specific implementation, the detection mechanism 130 can be movably mounted to the main body 110 and is vertically movable to sequentially detect the wafers W in the wafer cassette 200. For example... Figure 4 ,and Figures 6 to 8 As shown, the testing mechanism 130 may include a gantry-shaped testing frame, specifically as follows: Figure 6The detection frame has a horizontally extending horizontal bar 131a and vertical bars 131b extending vertically downward from both ends of the horizontal bar 131a. The detection frame can be movably mounted to the main body 110 via a vertically extending guide rail (not shown). A detector can be mounted on the detection frame. After the wafer cassette 200 is placed on the loading stage 120 and the movable door of the wafer cassette 200 is opened, the detection frame can move vertically along the guide rail, for example, from the top to the bottom of the window 111, so that the detector scans the wafers W in the wafer cassette 200 sequentially from top to bottom, thereby detecting the placement or warping state of the wafers W. It should be understood that the width of the detection frame (i.e., the length of the horizontal bar 131a) can be longer or shorter than the width of the window 111, as long as the detector on it can detect the wafers W.

[0062] In specific implementation methods, such as Figure 6 The detection mechanism 130 may include a warpage detector 132 and an analyzer (not shown) communicatively connected to the warpage detector 132. The warpage detector 132 may be positioned at the center of the horizontal bar 131a of the detection frame. The warpage detector 132 is configured to send a warpage detection signal to the analyzer. The magnitude of the warpage detection signal is related to the horizontal distance between the warpage detector 132 and the wafer W; that is, the smaller the horizontal distance between the warpage detector 132 and the wafer W, the larger the warpage detection signal. For example, the warpage detector 132 may be an infrared sensor that emits infrared light toward the wafer W and receives the infrared light reflected by the wafer W, then converts the received infrared light into an electrical signal to obtain the warpage detection signal. The smaller the horizontal distance between the infrared sensor and the wafer W, the stronger the reflected infrared light, and thus the larger the warpage detection signal. In an alternative embodiment, the warpage detector 132 may also employ other detectors with a similar distance-signal strength relationship, such as an ultrasonic detector.

[0063] like Figure 9 It shows Figure 5 A cross-sectional view of the wafer cell 200 at point AA, showing a warped wafer W. (See image) Figure 10 The detection process for the warped wafer W is shown, in which the following is illustrated: Figure 9The portion of wafer cassette 200 and wafer W captured at point B (dashed box) undergoes a change in horizontal distance between the warp detector 132 and wafer W as the warp detector 132 moves vertically with the detection frame (e.g., from top to bottom as indicated by the arrow). This change causes variations in the strength of the warp detection signal; for example, the warp detection signal increases as the horizontal distance between the warp detector and the wafer decreases. The analyzer is configured to determine the warp information of wafer W based on the warp detection signal and the vertical displacement of the warp detector 132. Specifically, the analyzer can generate a waveform image showing the change in the warp detection signal as the warp detector 132 changes with the vertical displacement of the warp detector 132, and determine the warp information of wafer W based on the shape of the waveform image. The warp information of wafer W may include the degree of warp and / or the warp direction, etc.

[0064] Figures 11-13 The diagram illustrates three waveform images generated by an analyzer according to one embodiment of this application, where the horizontal axis represents the vertical displacement of the warp detector 132, such as the vertical displacement when moving from top to bottom, with the origin corresponding to the top position of the wafer cassette 200; the vertical axis represents the magnitude of the warp detection signal. Each figure shows three spaced-apart convex waveforms 50, representing consecutive measurements of three vertically spaced stacked wafers W.

[0065] Figure 11 In the waveform image, there is a convex rectangular wave, that is, when the warp detector 132 passes through the wafer W, the horizontal distance between the wafer W and the warp detector 132 is consistent, and the warp detection signal is consistent. Therefore, it can be determined that the wafer W is a non-warp wafer W with a warp of 0. The thickness of the wafer W can be determined based on the width of the rectangular wave, that is, the width of the plateau region 51 of the rectangular wave.

[0066] Figure 12 and Figure 13 In the waveform image, the convex waveform 50 has a plateau region 51 and a curved region 52 continuous with the plateau region 51. That is, when the warp detector 132 passes through the wafer W, the horizontal distance between the wafer W and the warp detector 132 changes, and the magnitude of the warp detection signal changes. Thus, the corresponding wafer W can be determined to be a warped wafer. Among them, the plateau region 51 represents the situation when the warp detector 132 passes through the outer peripheral end face of the wafer W. The width of the plateau region 51 can represent the thickness of the wafer W. The curved region 52 represents the curved surface portion of the warped wafer W detected by the warp detector 132. The total width of the plateau region 51 and the curved region 52 continuous with it in the horizontal axis direction can represent the warp degree of the wafer W, that is, the maximum distance that the wafer W extends in the axial direction (thickness direction) of the wafer W, for example, the maximum distance that the edge of the wafer W deviates from the center of the wafer W in the axial direction of the wafer W.

[0067] More specifically, Figure 12 One of the waveforms 50 and Figure 10When the warp detector 132 moves from the first position P1 to the second position P2, the detection results between the two dashed lines are roughly consistent. In the vertical displacement direction of the warp detector 132, the curved area 52 is located downstream of the platform area 51 and the curved area 52 gradually decreases. Therefore, it can be determined that the warp direction of the corresponding wafer W is opposite to the vertical displacement direction of the warp detector 132. For example, if the warp detector 132 moves downwards, the wafer W warps upwards, that is, the middle of the wafer W is concave. Figure 9 The warping shape shown is, for example, referred to as bowl-shaped or smiley face-shaped. And... Figure 13 In the vertical displacement direction of the warp detector 132, the curved region 52 is located upstream of the platform region 51 and gradually rises. Therefore, it can be determined that the warp direction of the corresponding wafer W is the same as the vertical displacement direction of the warp detector 132. For example, if the warp detector 132 moves downwards, the wafer W warps downwards, meaning the middle of the wafer W convexes upwards. Figure 9 The warping state shown is reversed, for example, referred to as an inverted bowl shape or a sad face shape. In other embodiments, for wafers warped in other shapes (e.g., saddle shape, irregular bowl shape, or inverted bowl shape), the specific shape of the waveform image can also be used to determine the warping.

[0068] Furthermore, since wafer W has a certain degree of elasticity and the warped wafer surface may have a certain stress, vibrations may occur during the engagement of wafer cassette 200 with the main body 110 or during the opening of the movable door of wafer cassette 200, and the wafer may be subject to gravity, causing the warping state of wafer W to change. When the warping state of wafer W is a "crying face" (a specific type of warping), the warping information (warping degree) of wafer W output by the analyzer is calculated to be 100% - n% of the actual detected warping degree, where n can be calibrated to 0 to 2 according to the material and thickness of wafer W. In other words, when the warping direction is downward, the absolute value of the warping degree output by the analyzer based on the total width of the same curve area 52 and platform area 51 is lower than when the warping is upward. When the analyzer determines that the warping direction is a downward "crying face", it amplifies the calculated warping degree to increase the safety redundancy of setting the wafer picking position of the front-end robotic arm 101.

[0069] In a preferred embodiment, the smoothness of the warp can be determined by the curvature of the curve region 52, for example, Figure 12 and Figure 13 If the curvature of the curved region 52 is relatively consistent and basically the same, or if the curvature changes continuously without abrupt changes in curvature in other embodiments, then the warpage of the wafer can be determined to be relatively smooth, such as a smooth, regular bowl shape or inverted bowl shape; if there is an abrupt change in the curvature of the curved region 52, then the warpage can be determined to be relatively uneven, and there may be wavy warpage or bending areas.

[0070] Figure 6 and Figure 7Only one warp detector 132 is shown, directly opposite one diameter of the wafer, thus allowing detection of warp along that diameter. Figure 7 The warpage information (vertical direction) of the wafer. In a preferred embodiment, the detection mechanism may include two or more warpage detectors 132 arranged at intervals, for example, at equal intervals along the horizontal bar 131a. The analyzer can determine the warpage of the wafer in the arrangement direction of the two or more warpage detectors by analyzing and comparing the waveform images of the two or more warpage detectors 132. Figure 7 (in the left and right directions) and in the direction perpendicular to that arrangement direction (in the left and right directions) Figure 7 By analyzing the warp information (in the vertical direction) of the wafer, more accurate and comprehensive wafer warp information can be obtained, reducing detection errors and providing more accurate and effective information for subsequent transmission and processing.

[0071] According to the embodiments of this application, the warpage detector 132 and analyzer are set up in a simple manner and realize automated detection, avoiding the error of human eye detection. They can quickly and accurately determine the warpage information of wafer W, providing accurate wafer information for the subsequent wafer transfer and wafer processing processes. This facilitates timely and adaptive adjustment of the corresponding working parameters of the wafer transfer unit 40 and the wafer processing unit (e.g., the wafer picking position of the front-end robot 101), effectively preventing wafer collisions and fragmentation. It also facilitates timely unloading of wafers with excessive warpage or other defects that do not meet processing requirements, avoiding wafer breakage or damage to the wafer processing equipment during processing, improving the processing efficiency of the wafer processing equipment, and increasing the yield and service life of the wafer processing equipment.

[0072] When the warpage of wafer W output by warpage detector 132 is the unprocessed raw value, the wafer pick-up position setting of front-end robot 101 should take into account the vibration generated during the engagement of wafer cassette 200 and main body 110 or the opening of the movable door of wafer cassette 200, as well as the change in the warpage state of wafer W caused by the effect of gravity on the wafer. In particular, when the warpage state of wafer W is a sad face, the wafer pick-up position of front-end robot 101 should be lower than the actual position of wafer W after engagement, rather than just lower than the position information obtained during detection.

[0073] For example, when the warped state of wafer W is detected as a sad face, the wafer pick-up position of the front-end robot 101 should take the warped degree into account as X*(1+n)%, where X is the actual warped degree detected, and n can be set to 0 to 2 according to the material and thickness of wafer W.

[0074] In a preferred embodiment, the analyzer can also determine the placement state of wafer W based on waveform images. The placement state includes monolithic, stacked, and cross-slot states. The analyzer can be set with a wafer thickness threshold, for example, the actual wafer thickness might be 775 micrometers, 750 micrometers, or 725 micrometers, etc. The wafer thickness threshold can be slightly larger than these thicknesses, for example, 780 micrometers, 755 micrometers, 730 micrometers, etc., or for bonded wafers, its thickness can be twice these values. Furthermore, the analyzer can be set with a preset interval matching the vertical dimension of the horizontal slot 210 (i.e., the opening size of the horizontal slot 210 in the vertical direction). The method for determining the placement state is as follows:

[0075] The analyzer determines that the placement state is a single wafer state based on the fact that the width of the protruding waveform 50 in the waveform image is less than the preset interval, and the width of the platform area 51 of the protruding waveform 50 in the waveform image is less than or equal to the wafer thickness threshold, that is, the wafer W is in a horizontal slot 210 and only the thickness of one wafer W is identified.

[0076] The analyzer determines that the placement state is a stacked state, i.e., two or more wafers are placed in a horizontal slot 210, based on the fact that the width of the protruding waveform 50 in the waveform image is less than the preset interval and the width of the platform area 51 of the protruding waveform 50 in the waveform image is greater than the wafer thickness threshold.

[0077] The analyzer determines that the placement state is a slot-crossing state based on the fact that the width of the convex waveform 50 in the waveform image exceeds a preset interval, i.e., the wafer W crosses at least two horizontal slots 210.

[0078] According to the embodiments of this application, by integrating the detection of the placement state into the analyzer, the detection function of the detection mechanism 130 is further increased, the effectiveness of its detection of abnormal wafer states is improved, and abnormal wafers W are further prevented from entering subsequent processing flows, thereby improving the effectiveness and yield of wafer processing.

[0079] In addition, the analyzer can also detect the presence or absence of a wafer based on the waveform image. For example, if the waveform image does not show a protruding waveform 50 within a preset interval, it can be determined that no wafer is placed in the corresponding horizontal slot 210.

[0080] In a preferred embodiment, such as Figure 6 , Figure 7As shown, the detection mechanism 130 may further include a state detector 133 disposed on the horizontal bar 131a, configured to detect the placement state of the wafer in the horizontal slot 210. By adding the state detector 133, both the warpage detector 132 and the state detector 133 can perform placement state detection, thereby forming dual detection and reducing the error rate of the detection results. The state detector 133 may have a separate analyzer for data analysis, or it may share an analyzer with the warpage detector 132.

[0081] exist Figure 6 and Figure 7 In the illustrated embodiment, the state detector 133 is a through-beam sensor, which may include a transmitter and a receiver arranged horizontally at an interval, the receiver receiving the through-beam light emitted by the transmitter. A warp detector 132 may be disposed between the transmitter and the receiver. During wafer inspection, the inspection frame of the inspection mechanism 130 may move a distance through the window 111 toward the wafer cassette 200, causing the state detector 133 to at least partially extend into the wafer cassette 200 (e.g., ...). Figure 7 As the detection mechanism 130 moves vertically, the wafer W in the wafer cassette 200 passes between the transmitter and receiver to block the transmitted light. The through-beam sensor determines the placement state of the wafer W based on the time the receiver does not receive the transmitted light or the distance it moves during that time. The determination method of the through-beam sensor is, for example:

[0082] The through-beam sensor can determine that the placement state is a slot-crossing state if the distance moved when no through-beam light is received exceeds a preset interval.

[0083] The through-beam sensor can determine that the placement state is a single-wafer state based on the fact that the distance moved when no through-beam light is received is less than or equal to the wafer thickness threshold.

[0084] The through-beam sensor determines the wafer placement state as a stacked state based on the fact that the distance traveled when no through-beam light is received is greater than the wafer thickness threshold but less than a preset interval. It should be understood that for through-beam sensors without wafer warpage detection, when the wafer warpage is small and close to the wafer thickness during stacking, the sensor may have difficulty determining whether the "distance traveled when no through-beam light is received is greater than the wafer thickness threshold but less than the preset interval" is caused by stacking or wafer warpage. It may uniformly classify it as a stacked state. In this case, the through-beam sensor can serve as a preliminary judgment of the wafer placement state, and in further judgment, it can be used in conjunction with the warpage detector 132 for accurate determination.

[0085] Since time is directly proportional to the distance traveled, the method of determining the time based on the receiver not receiving the transmitted light is similar to the one described above, and will not be repeated here.

[0086] Alternatively, in an alternative implementation, the state detector 133 may take the form of other sensors, such as a vision sensor, which can accurately determine the wafer placement state through visual image detection. In this case, it can accurately distinguish between stacked wafer states and wafer warping, and can accurately distinguish between single-wafer states without warping and single-wafer states with warping.

[0087] In terms of execution steps, the wafer placement status detection by the state detector 133 can be performed before the warp detection by the warp detector 132. This allows for the elimination of at least one abnormal state, such as cross-slot or stacked wafers, before performing warp detection, thereby improving detection efficiency. Furthermore, in the event of an abnormal placement status, it can promptly provide feedback on abnormal information or alarms, reminding operators to take timely and appropriate countermeasures to prevent damage to processing equipment or personnel. Alternatively, in an optional embodiment, the wafer placement status detection by the state detector 133 can be performed synchronously with the warp detection and / or placement status detection by the warp detector 132, enabling dual detection and improving detection accuracy while reducing false alarms.

[0088] By setting up a state detector 133 and a warpage detector 132, the two can complement each other to perform dual detection and judgment on the placement state of the wafer, reduce detection errors, and improve detection accuracy.

[0089] In a preferred embodiment, the loading port device 100 further includes a display 140 (see [link to display]) that is communicatively connected to the detection mechanism 130. Figure 17 The display 140 is configured to receive and display wafer warpage information and wafer placement status information to provide relevant information to the operator, or to warn of abnormalities of the wafer W in the wafer cassette 200, such as wafer stacking, cross-slotting, or excessive warpage, using prominent graphic symbols. Optionally, the display 140 may be equipped with an audio output device to alert the wafer cassette 200 of abnormalities via audible alarms.

[0090] In a further embodiment, the inspection mechanism 130 may further include a vision detector 134, which is disposed toward the sidewall of the wafer cassette 200 such that its field of view can at least include the sidewall of the wafer cassette 200 and at least one horizontal slot 210 at the sidewall, such as... Figure 6 As shown, the vision detector 134 can be positioned at a corner of the detection frame, i.e., one end of the horizontal bar 131a or the top of the vertical bar 131b, or at any suitable location on the vertical bar 131b. The vision detector 134 can be configured to detect the edge of the wafer W at the horizontal slot 210 of the wafer cassette 200 and identify the horizontal distance between the edge of the wafer W and the sidewall of the wafer cassette 200 to determine wafer warpage information. Figure 14 It shows from Figure 5The simplified schematic diagram of the wafer cell 200 is shown in the direction of arrow C, where the dashed box D indicates the detection field of the vision detector 134. It should be understood that, in alternative embodiments, the detection field may be larger or smaller.

[0091] Figure 15 An enlarged view of the area within the dashed box D is shown. The vision detector 134 can construct a first virtual scale R1 extending horizontally inward from the inner surface of the wafer cassette's sidewall within its detection field of view, and read the scale corresponding to the wafer's edge to determine the horizontal spacing. Since a warped wafer is farther from the sidewall of the wafer cassette 200 than a non-warped wafer, the vision detector 134 can be configured to determine that the corresponding wafer is a warped wafer when the horizontal spacing is greater than a preset first spacing threshold. This allows it to transmit wafer warping information to the controller 150, guiding the front-end robot 101 to adjust its wafer pickup position (e.g., the height of the front-end robot 101 during pickup). The first spacing threshold can be approximately the horizontal distance between the non-warped wafer and the sidewall of the wafer cassette 200.

[0092] Furthermore, the vision detector 134 is also configured to identify the vertical distance between the edge of the wafer and the horizontal slot 210. Specifically, the vision detector 134 constructs a second virtual scale R2 extending vertically upward from the upper surface of the horizontal slot 210 in its detection field of view, and reads the scale corresponding to the edge of the wafer W to determine the vertical distance. When the wafer warps upward, i.e., in a bowl shape or smiley face shape, the edge of the wafer W will move away from the horizontal slot 210; when the wafer warps downward, i.e., in an inverted bowl shape or sad face shape, the edge of the wafer W will be close to the horizontal slot 210. Thus, the vision detector is configured to: determine the warping direction of the corresponding wafer as upward warping when the horizontal distance is greater than a first distance threshold and the vertical distance is greater than a preset second distance threshold; and determine the warping direction of the corresponding wafer as downward warping when the horizontal distance is greater than the first distance threshold and the vertical distance is not greater than the second distance threshold. The second spacing threshold can be approximately the vertical distance between the wafer and the horizontal slot 210 when the wafer is a non-warped wafer. The second spacing threshold can be a small value that is adapted to the slight warping of the wafer allowed when the front-end robot 101 picks up the wafer.

[0093] The greater the horizontal spacing between the wafer and the sidewall of the wafer cassette 200, the greater the wafer warpage; similarly, the greater the vertical spacing between the wafer and the horizontal slot 210, the greater the wafer warpage. Therefore, the degree of wafer warpage can be determined based on the horizontal and / or vertical spacing. When the warpage is determined to be significant and exceeds the wafer pick-up position tolerance of the front-end robot 101, the wafer pick-up position of the front-end robot 101 can be adjusted to ensure accurate and stable wafer pick-up, preventing risks such as wafer fragmentation due to impact.

[0094] By setting up a vision detector 134, warpage detection can be performed at the edge of the wafer, and warpage information can be easily and quickly obtained by reading the scale. The vision detector 134 can cooperate with the aforementioned warpage detector 132 to perform dual detection and verification of warpage information, reducing false positives. Furthermore, for wafers with metals in the device area that are susceptible to photo-etching, the vision detector 134 detects the edge of the wafer without requiring strong light irradiation of the central device area, thus avoiding optical damage to the device area and reducing the wafer damage rate.

[0095] In an optional implementation, besides setting a virtual scale, the visual detector 134 can be configured to identify whether a wafer is present at a horizontal distance of a first spacing threshold from the inner surface of the sidewall of the wafer cassette 200. If no wafer is present, it is determined that the horizontal distance between the wafer and the inner surface of the sidewall of the wafer cassette exceeds the first spacing threshold, thereby determining that the corresponding wafer is a warped wafer. If a wafer is detected, it is determined that the horizontal distance between the wafer and the inner surface of the sidewall of the wafer cassette does not exceed the first spacing threshold, thereby determining that the corresponding wafer is a non-warped wafer. This identification method is simple and convenient, and can improve wafer inspection efficiency.

[0096] In a preferred embodiment, two vision detectors 134 can be provided, which perform wafer detection at two opposite sidewalls of the wafer cassette 200, thereby improving detection accuracy and reducing misjudgments caused by horizontal wafer displacement. Alternatively, more than two vision detectors 134 can be provided.

[0097] Figure 16 A flowchart of a wafer inspection method according to one embodiment of this application is shown. The method includes:

[0098] S1: Open the movable door of the wafer box 200 so that the wafer W in the wafer box 200 is exposed toward the inspection mechanism 130;

[0099] S2: Control the detection mechanism 130 to move vertically to sequentially detect the wafers W in the wafer cassette 200;

[0100] S3: Output the detected wafer information.

[0101] Specifically, step S2 may include: detecting warpage information of wafer W via warpage detector 132. Alternatively, step S2 may also include: detecting the placement state of wafer W via warpage detector 132 and / or detecting the placement state of wafer W via state detector 133.

[0102] In one embodiment, the method may further include: adjusting the wafer-picking position of the front-end robot 101 used to pick up the wafer from the wafer cassette 200 based on wafer warpage information. For example, the wafer-picking height of the front-end robot 101 may be reduced based on the wafer being upwardly warped (with a concave portion), or the wafer-picking height of the front-end robot 101 may be increased based on the wafer being downwardly warped (with a convex portion). The specific adjustment value of the wafer-picking height may be further determined based on the wafer warpage. This avoids the front-end robot 101 from impacting the warped wafer, reducing the risk of wafer fragmentation.

[0103] Additionally, in a preferred embodiment, step S3 may include sending an instruction to controller 150 (see...). Figure 17 The system outputs the detected wafer W information and controls the display 140 via the controller 150 to output alarm prompt signals in the form of graphic icons or alarm sounds.

[0104] Figure 17 The execution was shown Figure 16 This is a flowchart illustrating an information processing step in a wafer inspection method. First, information is collected as the inspection mechanism 130 moves vertically. Then, the placement state of the wafer W is determined. If it is determined to be in a stacked or cross-slot state, the signal is transmitted to the controller 150 and further to the display 140. If it is determined to be in a single-wafer state, warpage information detection is performed, and the warpage information is transmitted to the controller 150 and further to the display 140. Warpage information detection can be performed by a warpage detector 132, while placement state detection can be performed by either the warpage detector 132 or the state detector 133. Figure 17 The information processing order shown is merely an example. Depending on the actual situation, some information processing orders may be executed synchronously or in reverse order.

[0105] This application also provides a computer storage medium storing a computer program that, when executed by a processor, implements the aforementioned wafer inspection method. Specifically, a system or apparatus equipped with a storage medium may be provided, on which software program code implementing the functions of any of the embodiments described above is stored, and the computer (or CPU or MPU) of the system or apparatus reads and executes the program code stored in the storage medium. In this case, the program code read from the storage medium itself can implement the functions of any of the embodiments described above; therefore, the program code and the storage medium storing the program code constitute a part of this application. Embodiments of storage media for providing program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, the program code can be downloaded from a server computer via a communication network.

[0106] The above embodiments are only used to illustrate the embodiments of this application, and are not intended to limit the embodiments of this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of this application. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of this application, and the patent protection scope of the embodiments of this application should be defined by the claims.

Claims

1. A loading port device for wafer processing equipment, characterized in that, The loading port device includes: main body; A loading stage protruding horizontally from the main body is used to place wafer cassettes. The wafer cassettes are used to stack wafers at intervals along a vertical direction. Each wafer cassette has a plurality of horizontal slots arranged vertically, extending from the sidewall of the wafer cassette into its interior. An inspection mechanism is movably mounted to the main body and is vertically movable to sequentially inspect wafers in the wafer cassette, the inspection mechanism including a vision detector disposed toward the sidewall; The visual detector is configured to: construct a first virtual scale extending horizontally inward from the inner surface of the sidewall in its detection field of view, and read the scale corresponding to the edge of the wafer to determine the horizontal distance between the edge of the wafer and the sidewall; and construct a second virtual scale extending vertically upward from the upper surface of the horizontal slot in its detection field of view, and read the scale corresponding to the edge of the wafer to determine the vertical distance between the edge of the wafer and the horizontal slot. When the horizontal spacing is greater than a first spacing threshold, the corresponding wafer is determined to be a warped wafer; when the horizontal spacing is greater than the first spacing threshold and the vertical spacing is greater than a second spacing threshold, the warping direction of the corresponding wafer is determined to be upward warping; when the horizontal spacing is greater than the first spacing threshold and the vertical spacing is not greater than the second spacing threshold, the warping direction of the corresponding wafer is determined to be downward warping; the degree of wafer warping is determined based on the horizontal spacing and / or the vertical spacing.

2. The loading port device according to claim 1, characterized in that, The greater the horizontal spacing and / or the greater the vertical spacing, the greater the degree of warpage the visual detector determines in the wafer.

3. The loading port device according to claim 1, characterized in that, The vision detector is configured to identify the horizontal distance between the edge of the wafer and the sidewall of the wafer cassette to determine wafer warpage information, including: the vision detector identifies whether a wafer is present at a horizontal distance of a first distance threshold from the inner surface of the sidewall of the wafer cassette; if no wafer is present, it is determined that the horizontal distance between the wafer and the inner surface of the sidewall of the wafer cassette exceeds the first distance threshold, thereby determining that the corresponding wafer is a warped wafer.

4. The loading port device according to claim 1, characterized in that, The detection mechanism further includes a warpage detector and an analyzer communicatively connected to the warpage detector. The warpage detector is configured to send a warpage detection signal to the analyzer, the warpage detection signal increasing as the horizontal distance from the warpage detector to the wafer decreases. The analyzer is configured to determine the warpage information of the wafer based on the warpage detection signal and the vertical displacement of the warpage detector.

5. The loading port device according to claim 4, characterized in that, The analyzer can generate a waveform image of the warpage detection signal as the vertical displacement of the warpage detector changes, and determine the warpage information of the wafer based on the shape of the waveform image, the warpage information including the degree of warpage and / or the warpage direction.

6. The loading port device according to claim 5, characterized in that, The analyzer determines that the corresponding wafer is a non-warped wafer based on the convex rectangular wave in the waveform image; the analyzer determines that the corresponding wafer is a warped wafer based on the convex waveform in the waveform image having a plateau region and a curved region continuous with the plateau region.

7. The loading port device according to claim 6, characterized in that, The analyzer determines that the warpage direction of the corresponding wafer is opposite to the vertical displacement direction of the warpage detector based on the fact that the curved region in the vertical displacement direction of the warpage detector is downstream of the plateau region and the curved region gradually descends; the analyzer also determines that the warpage direction of the corresponding wafer is the same as the vertical displacement direction of the warpage detector based on the fact that the curved region in the vertical displacement direction of the warpage detector is upstream of the plateau region and the curved region gradually rises.

8. The loading port device according to claim 6, characterized in that, The analyzer determines the warpage of the corresponding wafer based on the total width of the platform region and the continuous curve region in the vertical displacement direction of the warpage detector. When the warpage direction is downward, the absolute value of the warpage output by the analyzer based on the same total width is lower than that when the warpage is upward.

9. The loading port device according to claim 6, characterized in that, The analyzer is also configured to determine the warpage smoothness of the wafer based on the curvature of the curve region, to determine the warpage smoothness as smooth when the curvature of the curve region is the same or changes continuously, and to determine the warpage smoothness as non-smooth when there is an abrupt change in the curvature of the curve region.

10. The loading port device according to any one of claims 4-9, characterized in that, The analyzer is also configured to determine the wafer placement state based on the shape of the waveform image, the placement state including monolithic state, stacked state, and cross-slot state.

11. The loading port device according to claim 10, characterized in that, The wafer cassette has multiple horizontal slots arranged in a vertical direction for placing wafers, and the analyzer has a preset interval that matches the vertical dimension of the horizontal slots. The analyzer determines the placement state as a monolithic state based on the fact that the width of the convex waveform in the waveform image is less than the preset interval, and the width of the plateau region of the convex waveform in the waveform image is less than or equal to the wafer thickness threshold; and / or The analyzer determines the placement state as a stacked state based on the fact that the width of the convex waveform in the waveform image is less than the preset interval, and the width of the plateau region of the convex waveform in the waveform image is greater than the wafer thickness threshold; and / or The analyzer determines that the placement state is a slot-crossing state based on the fact that the width of the protruding waveform in the waveform image exceeds the preset interval.

12. The loading port device according to any one of claims 4-9, characterized in that, The detection mechanism includes two or more warp detectors arranged at intervals. The analyzer determines the warp information of the wafer in the arrangement direction of the two or more warp detectors and in the direction perpendicular to the arrangement direction by analyzing the waveform images of the two or more warp detectors.

13. A front-end loading device for wafer processing equipment, characterized in that, The front-end loading device includes: The loading port device according to any one of claims 1-12; A wafer cassette, which is movably placed onto the loading stage of the loading port device, the wafer cassette being configured to stack wafers at intervals in a vertical direction; A front-end robotic arm configured to pick up a wafer from or place a wafer into the wafer cassette, wherein the front-end loading device is configured to adjust the wafer picking position of the front-end robotic arm when the wafer warpage exceeds the wafer picking position tolerance of the front-end robotic arm.

14. A wafer processing equipment, characterized in that, The wafer processing equipment includes: The front-end loading device according to claim 13; Wafer processing unit; and A wafer transport device configured to transport a wafer from the front-end loading device to the wafer processing unit for wafer processing.

15. A wafer inspection method for use in a loading port device as described in any one of claims 1-12, characterized in that, The method includes: Open the movable door of the wafer cassette to expose the wafers inside the cassette toward the inspection mechanism; The detection mechanism is controlled to move vertically to sequentially detect the wafers in the wafer cassette; Output the detected wafer information.

16. The wafer inspection method according to claim 15, characterized in that, The method further includes: The wafer pick-up position of the front-end robot used to pick up the wafer from the wafer cassette is adjusted based on the wafer warp information.

Images