Wafer loading apparatus and wafer state detection method

Abstract

The application discloses a wafer loading device and a wafer state detection method. When a wafer box moves in a loading chamber, a detection device detects parameter information representing the type of wafers in the wafer box; a controller determines the type of wafers according to the parameter information; if the type of wafers is determined, it is determined that the wafers are normally placed in the wafer box and the state is normal; if the type of wafers is not determined, it is determined that the wafers are abnormally placed in the wafer box and the state is abnormal. It can be seen that the application can detect the type of wafers and determine the state of wafers, so that the loading chamber no longer has a limited requirement for the type of wafers; therefore, the same loading chamber can be used to load wafers with the same process but different types at the same time, and the same machine can be used to process the wafers at the same time, thereby reducing the number of machines, saving costs, and avoiding the problems of reduced production capacity caused by changes in loading parameters and increased equipment complexity caused by multiple loading chambers.

Description

Technical Field

[0001] The present application relates to the field of wafer processing, and in particular to a wafer loading device and a wafer status detection method. Background Art

[0002] Currently, before the wafer is transferred to the machine for processing, it is first placed in a wafer box. The wafer box has multiple slots, each slot is used to place a wafer, so multiple wafers can be placed in a wafer box; then, the wafer box is placed in a loading chamber according to a fixed position, so that the wafer can be transferred to the machine through the loading chamber.

[0003] Before the loading chamber sends the wafers into the machine, it must load the wafer box. The loading operation includes the loading chamber detecting the status of the wafers in the wafer box. The status of the wafers in the wafer box includes: the distribution status of all wafers in the wafer box; whether the wafers in the wafer box are tilted; whether there are overlapping wafers in the wafer box (that is, more than one wafer is placed in the same slot). The loading chamber will transmit the detected wafer status to the machine control system. When the machine control system detects that the status of a wafer is incorrect (the wafer is tilted or overlapped), it will control the machine to stop operating and issue a prompt.

[0004] With the continuous development of semiconductor technology, the types of wafers (materials, thicknesses, shapes, etc.) are also increasing. The existing method for detecting the status of wafers in loading chambers is as follows: the loading chambers are all set with loading parameters for fixed types of wafers in advance. These loading parameters serve as the basis for judging the status of the wafers. In this case, the type of wafer to be loaded is required to match the loading parameters set by the loading chamber, otherwise the wafer status detection cannot be successfully performed. In other words, the wafers detected in the loading chamber can only be wafers of the same type, which limits different types of wafers from being processed in the same machine. The general choice is to distinguish different types of wafers and assign them to different machines for processing.

[0005] However, some different types of wafers have the same process. In this case, assigning them to different machines for process processing will increase the number of machines, thereby increasing costs. At present, in order not to increase the number of machines, the following two solutions are usually selected: 1) When the type of wafer loaded in the loading chamber changes, the loading parameters of the loading chamber are changed to match the type of wafer to be loaded. However, each time the loading parameters of the loading chamber are changed, the machine will be shut down, which will increase the machine downtime and reduce production capacity. 2) Set up multiple loading chambers for a machine, each loading chamber corresponds to a type of wafer, that is, different types of wafers are loaded using different loading chambers. However, this will increase the complexity of the equipment. Summary of the Invention

[0006] The purpose of this application is to provide a wafer loading device and a wafer status detection method, which can detect the type of wafers in the loading chamber and determine the status of different types of wafers, so that the loading chamber no longer has restrictions on the type of wafers. Wafers with the same process but different types can be loaded simultaneously using the same loading chamber and can be processed simultaneously using the same machine, thereby reducing the number of machines, saving costs, and avoiding the problem of reduced production capacity due to changes in loading parameters and the problem of increased equipment complexity due to the setting of multiple loading chambers.

[0007] To solve the above technical problems, the present application provides a wafer loading device, comprising:

[0008] a loading chamber for loading wafers via a wafer cassette;

[0009] a detection device, configured to detect parameter information characterizing the type of the wafers in the wafer box when the wafer box in the loading chamber moves;

[0010] The controller is used to determine the type of the wafer based on parameter information characterizing the type of the wafer; if the type of the wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state; if the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state.

[0011] Optionally, the detection device includes:

[0012] a transmitter for emitting a laser beam having a fixed width;

[0013] a receiver for receiving the laser; the transmitter and the receiver are mounted relative to each other on the loading chamber, and the transmitter and the receiver are positioned in the loading chamber so that when the wafer box moves up and down in the loading chamber, all the wafers in the wafer box will pass through the laser in sequence;

[0014] The controller is specifically used to: determine the type of the wafer passing through the laser based on the changes in the laser intensity values ​​received at different laser receiving positions on the receiver when the laser is unobstructed.

[0015] Optionally, the emission direction of the laser is perpendicular to the movement direction of the wafer box in the loading chamber.

[0016] To solve the above technical problems, the present application further provides a wafer status detection method, which is applied to any of the above wafer loading devices; the wafer status detection method comprises:

[0017] When the wafer box in the loading chamber moves, obtaining parameter information characterizing the type of wafers in the wafer box detected by the detection device;

[0018] Determining the type of the wafer according to parameter information characterizing the type of the wafer;

[0019] If the type of the wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state;

[0020] If the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state.

[0021] Optionally, the detection device includes: a transmitter for emitting a laser beam having a fixed width, and a receiver for receiving the laser beam; when the wafer box in the loading chamber moves, the wafer in the wafer box passes through the laser beam;

[0022] The acquiring of parameter information characterizing the type of wafers in the wafer box detected by the detection device; and determining the type of the wafer according to the parameter information characterizing the type of the wafer include:

[0023] Obtaining laser intensity values ​​received at different laser receiving positions on the receiver;

[0024] The type of the wafer passing through the laser is determined based on the changes in the laser intensity values ​​received at the different laser receiving positions when the laser is not blocked.

[0025] Optionally, determining the type of the wafer passing through the laser according to changes in laser intensity values ​​received at different laser receiving positions includes:

[0026] Matching the changes in the laser intensity values ​​received at the different laser receiving positions with the type judgment conditions corresponding to the different wafer types; wherein the type judgment conditions corresponding to any wafer type include: the position range of the laser receiving position where the laser intensity value changes, the time range over which the laser intensity value continuously changes, and the laser intensity range;

[0027] The type of the wafer passing through the laser is determined based on a successful matching result between the change condition and the type judgment condition.

[0028] Optionally, matching the change in the laser intensity values ​​received at the different laser receiving positions with type judgment conditions corresponding to different wafer types; and determining the type of the wafer passing through the laser according to a successful matching result between the change and the type judgment condition, includes:

[0029] Constructing a three-dimensional model corresponding to the wafers on each slot in the wafer box according to the changes in the laser intensity values ​​received at the different laser receiving positions; the three-dimensional model is composed of three-dimensional coordinate axes: a position axis representing the laser receiving position, a time axis, and an intensity axis representing the laser receiving intensity;

[0030] Matching the coordinate ranges of the three-dimensional model corresponding to the target wafer under the three coordinate axes with the type judgment conditions corresponding to different wafer types; wherein the target wafer is a wafer in any slot in the wafer box;

[0031] The type of the target wafer is determined based on a successful matching result between the coordinate values ​​and the type judgment condition.

[0032] Optionally, the emission direction of the laser is parallel to the wafer normally placed in the wafer box and without warpage; the fixed width of the laser is less than or equal to the diameter of the wafer; and the wafer in the loading chamber moves at a constant speed in a direction perpendicular to the emission direction of the laser;

[0033] When a wafer having a first thickness and a first transparency and having no warpage passes through the laser, the laser intensity values ​​received at different laser receiving positions change as follows: the laser intensity values ​​at the different laser receiving positions all change from an initial laser intensity to a first laser intensity corresponding to the first transparency, and the first laser intensity is maintained for a first time before returning to the initial laser intensity; wherein the first time = the first thickness × the movement speed of the wafer;

[0034] When a wafer having a second thickness, a second transparency and a second warp passes through the laser, the changes in the laser intensity values ​​received at the different laser receiving positions are as follows: there is a laser receiving position where the laser intensity value changes from the initial laser intensity to the second laser intensity corresponding to the second transparency, and based on the second thickness and the second warp, the laser receiving position where the laser intensity value changes gradually changes.

[0035] Optionally, if the type of the wafer cannot be determined, determining that the wafer is abnormally placed in the wafer box and is in an abnormal state specifically includes:

[0036] If the change fails to successfully match the type judgment condition corresponding to the same wafer type, the abnormal placement state of the wafer in the wafer box is determined based on the change in the laser intensity values ​​received at the different laser receiving positions.

[0037] Optionally, determining the abnormal placement state of the wafer in the wafer box according to changes in the laser intensity values ​​received at the different laser receiving positions includes:

[0038] If the change in the laser intensity values ​​received at the different laser receiving positions is that the laser receiving position where the laser intensity changes changes changes along a certain tilt direction, it is determined that the wafer passing through the laser is placed tilted in the wafer box.

[0039] Optionally, determining the abnormal placement state of the wafer in the wafer box according to changes in the laser intensity values ​​received at the different laser receiving positions includes:

[0040] If the change in the laser intensity values ​​received at the different laser receiving positions is: the time for which the laser intensity value continuously changes is greater than the time range included in the type judgment condition corresponding to any wafer type, it is determined that the wafers passing through the laser are overlapped and placed in the wafer box.

[0041] The present invention provides a wafer loading device, wherein a loading chamber is used to load wafers through a wafer box; a detection device is used to detect parameter information characterizing the type of wafers in the wafer box when the wafer box in the loading chamber moves; a controller is used to determine the type of wafer based on the parameter information characterizing the type of wafer; if the type of wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state; if the type of wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state. It can be seen that the present application can detect the type of wafer in the loading chamber and can also determine the state of different types of wafers, so that the loading chamber no longer has restrictions on the type of wafer. Then, for wafers with the same process but different types, they can be loaded simultaneously using the same loading chamber and can be processed simultaneously using the same machine, thereby reducing the number of machines, saving costs, and avoiding the problem of reduced production capacity due to changes in loading parameters and the problem of increased equipment complexity due to the provision of multiple loading chambers.

[0042] The present invention also provides a wafer status detection method, which has the same beneficial effects as the above-mentioned wafer loading device. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in this application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0044] Figure 1 A schematic structural diagram of a wafer loading device provided in an embodiment of the present application;

[0045] Figure 2 A top view of a wafer loading device provided in an embodiment of the present application;

[0046] Figure 3 A side view in direction A of a wafer loading device provided in an embodiment of the present application;

[0047] Figure 4 A side view in direction B of a wafer loading device provided in an embodiment of the present application;

[0048] Figure 5 A flowchart of a wafer status detection method provided in an embodiment of the present application;

[0049] Figure 6 A schematic diagram of constructing a three-dimensional model of a different type of wafer provided in an embodiment of the present application;

[0050] Figure 7 A schematic diagram of constructing a three-dimensional model of a tilted wafer provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] The core of this application is to provide a wafer loading device and a wafer status detection method, which can detect the type of wafers in the loading chamber and determine the status of different types of wafers, so that the loading chamber no longer has restrictions on the type of wafers. Wafers with the same process but different types can be loaded simultaneously using the same loading chamber and can be processed simultaneously using the same machine, thereby reducing the number of machines, saving costs, and avoiding the problem of reduced production capacity due to changes in loading parameters and the problem of increased equipment complexity due to the setting of multiple loading chambers.

[0052] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0053] Please refer to Figure 1 , Figure 1 A schematic structural diagram of a wafer loading device provided in an embodiment of the present application.

[0054] The wafer loading equipment includes:

[0055] A loading chamber 100 is used to load wafers 102 through a wafer cassette 101;

[0056] The detection device 200 is used to detect parameter information representing the type of wafers 102 in the wafer box 101 when the wafer box 101 moves in the loading chamber 100;

[0057] The controller 300 is used to determine the type of the wafer 102 based on the parameter information characterizing the type of the wafer 102; if the type of the wafer 102 is determined, it is determined that the wafer 102 is placed normally in the wafer box 101 and is in a normal state; if the type of the wafer 102 cannot be determined, it is determined that the wafer 102 is placed abnormally in the wafer box 101 and is in an abnormal state.

[0058] like Figure 1 As shown, the wafer loading equipment includes: a loading chamber 100, a detection device 200 and a controller 300. The detection device 200 is connected to the controller 300 via a signal cable 301 to transmit signals to the controller 300 for processing. The wafer 102 is placed in a wafer box 101. The wafer box 101 has multiple slots, each for placing a wafer. The wafer box 101 is placed in the loading chamber 100 according to a fixed position. Before the loading chamber 100 sends the wafer box 101 to the machine, the status of the wafer 102 in the wafer box 101 must be detected.

[0059] The processing procedures for different wafers in the wafer cassette 101 are the same, but there may be more than one type of wafer in the wafer cassette 101. When detecting the status of the wafers 102 in the wafer cassette 101, the wafer cassette 101 moves up and down within the loading chamber 100. Based on this, the detection principle for detecting the status of the wafers 102 is as follows: the detection device 200 can detect parameter information indicating the type of the wafers 102 in the wafer cassette 101 as the wafer cassette 101 moves within the loading chamber 100, and transmit the detected parameter information indicating the type of the wafers 102 to the controller 300. After receiving the parameter information characterizing the type of wafer 102, the controller 300 can determine the type of wafer 102 based on the parameter information characterizing the type of wafer 102. If the type of wafer 102 is determined, it is determined that wafer 102 is placed normally in wafer box 101, that is, the status of wafer 102 is normal; if the type of wafer 102 cannot be determined, it is determined that wafer 102 is placed abnormally in wafer box 101, that is, the status of wafer 102 is abnormal.

[0060] The present application provides a wafer loading device that can detect the type of wafer in the loading chamber and determine the status of different types of wafers, so that the loading chamber no longer has any restrictions on the type of wafer. Wafers with the same process but different types can be loaded simultaneously using the same loading chamber and can be processed simultaneously using the same machine, thereby reducing the number of machines, saving costs, and avoiding the problem of reduced production capacity due to changes in loading parameters and the problem of increased equipment complexity due to the provision of multiple loading chambers.

[0061] Please refer to Figure 2 , Figure 2 A top view of a wafer loading device provided in an embodiment of the present application.

[0062] As an optional embodiment, the detection device 200 includes:

[0063] The transmitter 201 is configured to emit a laser beam L having a fixed width;

[0064] The receiver 202 is configured to receive the laser light L. The transmitter 201 and the receiver 202 are mounted relative to each other on the loading chamber 100 , and the transmitter 201 and the receiver 202 are positioned in the loading chamber 100 such that when the wafer cassette 101 is raised and lowered within the loading chamber 100 , all wafers in the wafer cassette 101 will sequentially pass through the laser light L.

[0065] The controller 300 is specifically used to: determine the type of wafer passing through the laser L based on the changes in the laser intensity values ​​received at different laser receiving positions on the receiver 202 when the laser L is not blocked.

[0066] In a specific application, the detection device 200 includes a transmitter 201 and a receiver 202. The transmitter 201 and the receiver 202 are mounted relative to each other at fixed positions in the loading chamber 100. The mounting positions of the transmitter 201 and the receiver 202 must satisfy the following requirements: the transmitter 201 emits a laser beam L with a fixed width through a lens. When the wafer cassette 101 moves up and down within the loading chamber 100, all wafers in the wafer cassette 101 will sequentially pass through the laser beam L. The laser receiving position on the receiver 202 is mounted relative to the lens of the transmitter 201. The receiver 202 is used to receive the laser beam L with a fixed width emitted by the transmitter 201. The transmitter 201 and the receiver 202 are respectively connected to the controller 300 via signal cables 301 to provide real-time signal feedback to the controller 300 for processing.

[0067] Different wafer types are primarily distinguished based on wafer thickness, wafer warp, and wafer transparency. It can be understood that the time wafer 102 blocks laser light L when passing through laser light L can indicate the thickness of wafer 102; the laser receiving position on receiver 202 corresponding to the blocked laser light L when passing through laser light L can indicate the warp of wafer 102; and the laser intensity received at the laser receiving position on receiver 202 when passing through laser light L can indicate the transparency of wafer 102. Therefore, different types of wafers will experience different blocking times (due to different wafer thicknesses), different laser receiving positions on receiver 202 corresponding to the blocked laser light L (due to different wafer warp), and different laser intensities received at the laser receiving positions on receiver 202 (due to different wafer transparencies). Based on this, controller 300 can determine the type of wafer that has passed through laser light L based on the changes in laser intensity values ​​received at different laser receiving positions on receiver 202. Specifically, the receiver 202 sends the laser intensity values ​​received at different laser receiving positions on the receiver 202 to the controller 300. After obtaining the laser intensity values ​​received at different laser receiving positions on the receiver 202 (i.e., the parameter information characterizing the type of wafer), the controller 300 uses the laser intensity received at different laser receiving positions on the receiver 202 when the laser L is unobstructed as a reference and determines the type of wafer that has passed through the laser L based on the changes in the laser intensity values ​​received at different laser receiving positions on the receiver 202.

[0068] In addition, the detection device 200 may use a CCD (Charge-coupled Device) image sensor or a transmitter and a receiver in a laser recognition sensor to implement the above-mentioned corresponding functions.

[0069] As an optional embodiment, the emission direction of the laser L is perpendicular to the movement direction of the wafer box 101 in the loading chamber 100 .

[0070] For specific applications, please refer to Figure 3 and Figure 4 ( Figure 3 and Figure 4 In the figure, 1021: transparent wafer, 1022: warped wafer, 1023: standard wafer, 1024: thick wafer), the emission direction of the laser L is parallel to the wafers that are normally placed and have no warpage in the wafer box 101, and the emission direction of the laser L is perpendicular to the movement direction of the wafer box 101 in the loading chamber 100. As the wafer box 101 moves, all wafers in the wafer box 101 will pass through the laser L at a uniform speed in turn.

[0071] Based on the above wafer loading equipment, the embodiment of the present application provides a wafer status detection method. Figure 5 , Figure 5 A flowchart of a wafer status detection method provided in an embodiment of the present application is provided. Figure 5 The method in can be Figure 1 The controller execution in Figure 5 As shown, the method includes the following steps:

[0072] Step S101 : when a wafer box in a loading chamber moves, parameter information characterizing the type of wafers in the wafer box detected by a detection device is obtained.

[0073] Step S102: determining the type of the wafer based on parameter information characterizing the type of the wafer.

[0074] Step S103: If the type of the wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state.

[0075] Step S104: If the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state.

[0076] In a specific application, when a wafer cassette moves within a loading chamber, a detection device can detect parameter information characterizing the type of wafers in the cassette and transmit the detected parameter information characterizing the type of the wafers to a controller. After receiving the parameter information characterizing the type of the wafers, the controller can determine the type of the wafers based on the parameter information characterizing the type of the wafers. If the type of the wafers can be determined, it is determined that the wafers are properly placed within the cassette, i.e., the wafers are in a normal state. If the type of the wafers cannot be determined, it is determined that the wafers are abnormally placed within the cassette, i.e., the wafers are in an abnormal state.

[0077] The present application provides a wafer status detection method that can detect the type of wafer in a loading chamber and determine the status of different types of wafers, so that the loading chamber no longer has restrictions on the type of wafer. Wafers with the same process but different types can be loaded simultaneously using the same loading chamber and can be processed simultaneously using the same machine, thereby reducing the number of machines, saving costs, and avoiding the problem of reduced production capacity due to changes in loading parameters and the problem of increased equipment complexity due to the setting of multiple loading chambers.

[0078] As an optional embodiment, the detection device includes: a transmitter for emitting a laser beam having a fixed width, and a receiver for receiving the laser beam; when the wafer box in the loading chamber moves, the wafers in the wafer box pass through the laser beam;

[0079] Obtaining parameter information characterizing the type of wafers in the wafer box detected by the detection device; determining the type of the wafer according to the parameter information characterizing the type of the wafer, including:

[0080] Obtain the laser intensity values ​​received at different laser receiving positions on the receiver;

[0081] The laser intensity received at different laser receiving positions when the laser is not blocked is used as a benchmark, and the type of wafer passing through the laser is determined according to the change in the laser intensity values ​​received at different laser receiving positions.

[0082] In specific applications, the detection device includes a transmitter and a receiver, which are mounted relative to each other at fixed positions within the loading chamber. Their mounting positions must ensure that: the transmitter emits a fixed-width laser beam through a lens, and as the wafer cassette moves up and down within the loading chamber, all wafers within the cassette pass through the laser beam. The receiver's laser receiving position is mounted relative to the transmitter's lens and is used to receive the fixed-width laser beam emitted by the transmitter. Each transmitter and receiver is connected to a controller via signal cables, providing real-time signal feedback to the controller for processing.

[0083] Different wafer types are mainly distinguished based on three aspects: wafer thickness, wafer warpage, and wafer transparency. It can be understood that when the wafer passes through the laser, the time the laser is blocked can represent the thickness of the wafer; when the wafer passes through the laser, the laser receiving position on the receiver corresponding to the blocked laser can represent the warpage of the wafer; when the wafer passes through the laser, the laser intensity received at the laser receiving position on the receiver can represent the transparency of the wafer. Therefore, when different types of wafers pass through the laser, the time the laser is blocked (different wafer thicknesses), the laser receiving position on the receiver corresponding to the blocked laser (different wafer warpages), and the laser intensity received at the laser receiving position on the receiver (different wafer transparencies) are different. Based on this, the controller can determine the type of wafer passing through the laser according to the changes in the laser intensity values ​​received at different laser receiving positions on the receiver. Specifically, the receiver sends the laser intensity values ​​received at its own different laser receiving positions to the controller. After obtaining the laser intensity values ​​received at different laser receiving positions on the receiver (i.e., the parameter information characterizing the type of wafer mentioned above), the controller uses the laser intensity received at different laser receiving positions on the receiver when the laser is unobstructed as a reference, and determines the type of wafer passing through the laser according to the changes in the laser intensity values ​​received at different laser receiving positions on the receiver.

[0084] As an optional embodiment, determining the type of the wafer passing through the laser according to changes in laser intensity values ​​received at different laser receiving positions includes:

[0085] Matching the changes in laser intensity values ​​received at different laser receiving positions with the type judgment conditions corresponding to different wafer types; wherein the type judgment conditions corresponding to any wafer type include: the position range of the laser receiving position where the laser intensity value changes, the time range over which the laser intensity value continuously changes, and the laser intensity range;

[0086] The type of the wafer passing through the laser is determined based on the successful matching of the change situation with the type judgment conditions.

[0087] In specific applications, the controller stores in advance the type judgment conditions corresponding to different wafer types. The type judgment conditions corresponding to any wafer type are characterized by: when a wafer of this wafer type passes through the laser, the change in the laser intensity value at different laser receiving positions on the receiver. Specifically, the type judgment conditions corresponding to any wafer type include: the position range of the laser receiving position where the laser intensity value changes (as a judgment condition for the wafer warpage, different position ranges are set to correspond to different warpage types of the wafer), the time range in which the laser intensity value continuously changes (as a judgment condition for the wafer thickness, different time ranges are set to correspond to different thickness types of the wafer), and the laser intensity range (as a judgment condition for the wafer transparency, different intensity ranges are set to correspond to different transparency types of the wafer).

[0088] Based on this, after obtaining the laser intensity values ​​received by different laser receiving positions on the receiver, the controller uses the laser intensity received by different laser receiving positions on the receiver when the laser is unobstructed as a reference, and matches the changes in the laser intensity values ​​received by different laser receiving positions on the receiver with the type judgment conditions corresponding to the different stored wafer types. If the changes in the laser intensity values ​​received at different laser receiving positions successfully match the type judgment conditions corresponding to the same wafer type, the type of the wafer that has just passed through the laser is determined to be: the wafer type corresponding to the matched type judgment conditions (the wafer status is normal); if the changes in the laser intensity values ​​received at different laser receiving positions fail to successfully match the type judgment conditions corresponding to the same wafer type, the type of the wafer that has just passed through the laser cannot be determined (the wafer status is abnormal).

[0089] As an optional embodiment, the changes in the laser intensity values ​​received at different laser receiving positions are matched with type judgment conditions corresponding to different wafer types; and the type of the wafer passing through the laser is determined based on the successful matching result of the changes with the type judgment conditions, including:

[0090] Based on the changes in the laser intensity values ​​received at different laser receiving positions, a three-dimensional model corresponding to the wafers in each slot in the wafer box is constructed. The three-dimensional model consists of three dimensional coordinate axes: the position axis representing the laser receiving position, the time axis, and the intensity axis representing the laser receiving intensity.

[0091] Matching the coordinate ranges of the three-dimensional model corresponding to the target wafer on the three coordinate axes with the type judgment conditions corresponding to different wafer types; wherein the target wafer is a wafer in any slot in the wafer box;

[0092] The type of the target wafer is determined based on the successful matching result of the coordinate values ​​and the type judgment conditions.

[0093] In specific applications, the type determination criteria for any wafer type include: the position range of the laser receiving position where the laser intensity value changes, the time range over which the laser intensity value continuously changes, and the laser intensity range. A three-dimensional coordinate system consisting of three dimensional coordinate axes (position axis, time axis, and intensity axis) can be established. Based on this three-dimensional coordinate system, a three-dimensional model corresponding to the wafer can be established. Specifically, the controller constructs a three-dimensional model of the wafer in each slot of the wafer cassette within the three-dimensional coordinate system based on the changes in laser intensity values ​​received at different laser receiving positions on the receiver within the entire scanning range from the start to the end of laser detection.

[0094] Based on this, taking the wafer on any slot in the wafer box (called the target wafer) as an example, the wafer type judgment principle is explained: the controller matches the coordinate range of the three-dimensional model corresponding to the target wafer under the three-dimensional coordinate axis with the type judgment conditions corresponding to different wafer types. If the coordinate range under the three-dimensional coordinate axis is successfully matched with the type judgment condition corresponding to the same wafer type, the type of the target wafer is determined to be: the wafer type corresponding to the matched type judgment condition (the wafer status is normal); if the coordinate range under the three-dimensional coordinate axis is not successfully matched with the type judgment condition corresponding to the same wafer type, the type of the target wafer cannot be determined (the wafer status is abnormal).

[0095] As an optional embodiment, the laser emission direction is parallel to the wafers normally placed in the wafer box without warpage; the fixed width of the laser is less than or equal to the diameter of the wafer; and the wafers in the loading chamber move at a constant speed in a direction perpendicular to the laser emission direction;

[0096] When a wafer having a first thickness and a first transparency and no warpage passes through a laser, the laser intensity values ​​received at different laser receiving positions change as follows: the laser intensity values ​​at the different laser receiving positions all change from an initial laser intensity to a first laser intensity corresponding to the first transparency, and the first laser intensity is maintained for a first time before returning to the initial laser intensity; where the first time = first thickness × wafer movement speed;

[0097] When a wafer having a second thickness, a second transparency and a second warp passes through the laser, the changes in the laser intensity values ​​received at different laser receiving positions are as follows: there is a laser receiving position where the laser intensity value changes from the initial laser intensity to the second laser intensity corresponding to the second transparency, and based on the second thickness and the second warp, the laser receiving position where the laser intensity value changes gradually changes.

[0098] In specific applications, the fixed width of the laser is less than or equal to the diameter of the wafer in the wafer box, the emission direction of the laser is parallel to the wafer that is normally placed and has no warping in the wafer box, and the emission direction of the laser is perpendicular to the movement direction of the wafer box in the loading chamber. As the wafer box moves, all wafers in the wafer box will pass through the laser in the fixed position in turn at a uniform speed (specifically: the laser is emitted in the horizontal direction, and the wafer box in the loading chamber moves at a uniform speed from top to bottom).

[0099] Based on this, an example of constructing a wafer 3D model is given. If a wafer cassette contains four slots, and the four slots are placed with thick wafers, standard wafers, downward warped wafers, and transparent wafers (thick wafers, standard wafers, and transparent wafers are all free of warpage), then the construction principle of the 3D model corresponding to the wafers placed in this wafer cassette is as follows:

[0100] Please refer to Figure 6 Since the spacing between adjacent slots in the wafer box is the same and the wafer box moves at a constant speed in the loading chamber, each slot in the wafer box can be expressed using a fixed time range. Figure 6 The a1, a2, a3, and a4 (a1=a2=a3=a4) in the figure are the time ranges corresponding to the slots in the wafer box. The controller maps the slots of the wafer box to the time ranges in sequence. The wafers placed in the slots of the wafer box are constructed into a three-dimensional model according to the following process ( Figure 6 Where c is the position width of the laser, and b is the laser intensity received at the laser receiving position on the receiver when no wafer passes through the laser):

[0101] Construction of the thick wafer model: When the thick wafer passes through the laser at a constant speed, the thick wafer blocks the laser, preventing the laser from entering the receiver. The laser intensity value received at the laser receiving position on the receiver changes from b to h1. Since the thick wafer has no warpage, when the thick wafer passes through the laser, the thick wafer will block the entire width of the laser at the same time. On the same time scale, the laser intensity value at each laser receiving position within the width of the laser on the position axis is the same. As the wafer box moves at a constant speed, the thick wafer will continue to block the laser. After the thick wafer passes through the laser, the laser intensity value received at the laser receiving position on the receiver will change from h1 back to b. When the laser intensity is h1, the time t1 that passes on the time axis is the time it takes for the thick wafer to pass through the laser. Figure 6 In the middle, "d" represents the three-dimensional model constructed by the controller through calculation when the thick wafer passes through the laser.

[0102] Construction of the standard wafer model: When the standard wafer passes through the laser at a constant speed, the laser cannot enter the receiver because the standard wafer blocks the laser. The laser intensity value received at the laser receiving position on the receiver changes from b to h2. Since the standard wafer has no warpage, when the standard wafer passes through the laser, the standard wafer will simultaneously block the entire width of the laser. On the same time scale, the laser intensity value at each laser receiving position within the width of the laser on the position axis is the same. As the wafer box moves at a constant speed, the standard wafer will continue to block the laser. After the standard wafer passes through the laser, the laser intensity value received at the laser receiving position on the receiver will change from h2 back to b. When the laser intensity is h2, the time t2 elapsed on the time axis is the time it takes for the standard wafer to pass through the laser. Figure 6 In the figure e, the controller constructs a three-dimensional model through calculation when the standard wafer passes through the laser.

[0103] Constructing a downward warped wafer model: When a downward-warped wafer passes through a laser beam at a constant speed, the warped portions of the wafer initially block the laser beam from the top to the bottom. At this point, the laser intensity at the receiver's receiving locations on both sides of the laser beam changes from b to h3, while the laser intensity at the unblocked laser beam remains at b. As the downward-warped wafer moves, it gradually shifts from blocking the laser beam to the center of the laser beam. During this process, the laser intensity at the receiver's receiving locations also gradually changes. When the downward-warped wafer finally passes through the laser beam, the laser intensity at all receiving locations returns to b. Over time, the intensity at different laser receiving locations forms a circular curve consistent with the wafer's warp. This circular curve spans time t3. Figure 6 In the middle, f is the three-dimensional model constructed by the controller through calculation when the downward-warped wafer passes through the laser.

[0104] Construction of a transparent wafer model: When a transparent wafer passes through a laser beam at a constant speed, it cannot completely block the laser beam, resulting in a significant amount of laser light being received by the receiver. Consequently, the intensity on the intensity axis is significantly higher than that of an opaque wafer. As the transparent wafer passes through the laser beam, the laser intensity at the laser receiving position on the receiver changes from b to h4. Because the transparent wafer has no warpage, it simultaneously blocks the entire width of the laser beam as it passes through the laser beam. On the same time scale, the laser intensity at each laser receiving position within the laser beam width on the position axis is the same. As the wafer cassette moves at a constant speed, the transparent wafer continues to block the laser beam. After the transparent wafer passes through the laser beam, the laser intensity at the laser receiving position on the receiver changes from h4 back to b. When the laser intensity is h4, the time t4 elapsed on the time axis represents the time it took the transparent wafer to pass through the laser beam. Figure 6 In the middle, g is the three-dimensional model constructed by the controller through calculation when the transparent wafer passes through the laser.

[0105] It should be noted that the principles of constructing a three-dimensional wafer model for other types of wafers that are different from the wafers in the above-mentioned embodiment in thickness, transparency, and warpage are similar to those of the wafers in the above-mentioned embodiment, and this application will not describe them one by one here.

[0106] As an optional embodiment, if the type of the wafer cannot be determined, determining that the wafer is abnormally placed in the wafer box and is in an abnormal state includes:

[0107] If the change does not successfully match the type judgment condition corresponding to the same wafer type, the abnormal placement state of the wafer in the wafer box is determined based on the change in the laser intensity values ​​received at different laser receiving positions.

[0108] In specific applications, when the changes in the laser intensity values ​​received by the controller at different laser receiving positions on the receiver fail to successfully match the type judgment conditions corresponding to the same wafer type, the type of wafer passing through the laser cannot be determined (the wafer status is abnormal). At this time, the specific abnormal placement status of the wafer in the wafer box can be determined based on the changes in the laser intensity values ​​received at different laser receiving positions on the receiver.

[0109] As an optional embodiment, determining an abnormal placement state of a wafer in a wafer box based on changes in laser intensity values ​​received at different laser receiving positions includes:

[0110] If the laser intensity values ​​received at different laser receiving positions change as follows: the laser receiving position where the laser intensity changes changes along a certain tilt direction, it is determined that the wafer passing through the laser is placed tilted in the wafer box.

[0111] In specific applications, abnormal wafer placement within the cassette includes tilted wafers, which are called tilted wafers. A tilted wafer is identified as such if the laser intensity changes at the receiver's position along a specific tilted direction when the wafer passes through the laser.

[0112] Based on this, when the change in the laser intensity value received by the controller at different laser receiving positions on the receiver fails to successfully match the type judgment condition corresponding to the same wafer type, if the laser receiving position on the receiver where the laser intensity changes changes changes along a certain tilt direction, it is determined that the wafer that has just passed through the laser is placed tilted in the wafer box.

[0113] Specifically, in the wafer 3D model, wafer tilt can be determined by the time axis and position axis. Figure 7 When the tilted wafer passes through the laser at a constant speed, since the tilted wafer is not parallel to the laser, when the tilted wafer passes through the laser at a constant speed from top to bottom, the downward-tilted side of the tilted wafer will first block the laser. At this time, the laser intensity value received by the receiver at the laser receiving position for the blocked laser position changes from b to h3, while the laser intensity received by the receiver at the laser receiving position for the unblocked laser position remains b. As the tilted wafer moves, the position where the tilted wafer blocks the laser will gradually move from the downward-tilted side to the other side of the tilted wafer. During this process, the laser receiving position at which the laser intensity value received on the receiver changes also gradually changes. When the tilted wafer finally passes completely through the laser, the laser intensity at all laser receiving positions received by the receiver returns to b. In this way, as time changes, the intensity of different laser receiving positions forms a model consistent with the tilt direction of the tilted wafer. The time spent on the time axis for this tilted model is the entire time in the range a5. Figure 7 Where k is the three-dimensional model constructed by the controller through calculation when the tilted wafer passes through the laser.

[0114] As an optional embodiment, determining an abnormal placement state of a wafer in a wafer box based on changes in laser intensity values ​​received at different laser receiving positions includes:

[0115] If the change in the laser intensity values ​​received at different laser receiving positions is: the time for which the laser intensity values ​​continuously change is greater than the time range included in the type judgment condition corresponding to any wafer type, it is determined that the wafers passing through the laser are overlapped and placed in the wafer box.

[0116] In specific applications, abnormal wafer placement within a cassette also includes overlapping wafers (i.e., more than one wafer is placed in the same slot). These wafers are referred to as overlapping wafers. Overlapping wafers are identified (based on a timeline): if the laser intensity values ​​at different laser receiving locations on the receiver continuously change for a period greater than the time range specified by the wafer type determination criteria when the wafer passes through the laser beam, the wafer is considered an overlapping wafer.

[0117] Based on this, when the changes in the laser intensity values ​​received by the controller at different laser receiving positions on the receiver fail to successfully match the type judgment conditions corresponding to the same wafer type, if the time for which the laser intensity values ​​received at different laser receiving positions on the receiver continuously change is greater than the time range included in the type judgment conditions corresponding to any wafer type, it is determined that the wafers that have just passed through the laser are overlapped and placed in the wafer box.

[0118] In summary, the wafer status detection method of the present application solves the problem in the prior art that the loading chamber cannot simultaneously detect different types of wafers in the same loading chamber, resulting in increased machine costs, reduced production capacity and increased equipment complexity when different types of wafers need to undergo the same process.

[0119] Those skilled in the art will appreciate that, with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0120] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, and this is merely a way of distinguishing the objects of the same attributes when describing them in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A wafer loading device, characterized in that: include: a loading chamber for loading wafers via a wafer cassette; a detection device, configured to detect parameter information characterizing the type of the wafers in the wafer cassette when the wafer cassette in the loading chamber moves, wherein the type of the wafer is based on the following three aspects: wafer thickness, wafer warpage, and wafer transparency; The controller is used to determine the type of the wafer based on parameter information characterizing the type of the wafer; if the type of the wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state; if the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state.

2. The wafer loading device according to claim 1, wherein: The detection device comprises: a transmitter for emitting a laser beam having a fixed width; a receiver for receiving the laser; the transmitter and the receiver are mounted relative to each other on the loading chamber, and the transmitter and the receiver are positioned in the loading chamber so that when the wafer box moves up and down in the loading chamber, all the wafers in the wafer box will pass through the laser in sequence; The controller is specifically used to: determine the type of the wafer passing through the laser based on the changes in the laser intensity values ​​received at different laser receiving positions on the receiver when the laser is unobstructed.

3. The wafer loading device according to claim 2, wherein: The emission direction of the laser is perpendicular to the movement direction of the wafer box in the loading chamber.

4. A wafer status detection method, characterized in that: Applicable to the wafer loading equipment according to any one of claims 1 to 3; The wafer status detection method includes: When a wafer cassette in a loading chamber moves, parameter information characterizing a type of wafer in the wafer cassette detected by a detection device is obtained, wherein the type of the wafer is based on the following three aspects: wafer thickness, wafer warpage, and wafer transparency; Determining the type of the wafer according to parameter information characterizing the type of the wafer; If the type of the wafer is determined, it is determined that the wafer is normally placed in the wafer box and is in a normal state; If the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state.

5. The wafer status detection method according to claim 4, wherein: The detection device includes: a transmitter for emitting a laser beam having a fixed width, and a receiver for receiving the laser beam; when the wafer box in the loading chamber moves, the wafer in the wafer box passes through the laser beam; The acquiring of parameter information characterizing the type of wafers in the wafer box detected by the detection device; and determining the type of the wafer according to the parameter information characterizing the type of the wafer include: Obtaining laser intensity values ​​received at different laser receiving positions on the receiver; The type of the wafer passing through the laser is determined based on the changes in the laser intensity values ​​received at the different laser receiving positions when the laser is not blocked.

6. The wafer status detection method according to claim 5, wherein: The determining the type of the wafer passing through the laser according to changes in the laser intensity values ​​received at different laser receiving positions includes: Matching the changes in the laser intensity values ​​received at the different laser receiving positions with the type judgment conditions corresponding to the different wafer types; wherein the type judgment conditions corresponding to any wafer type include: the position range of the laser receiving position where the laser intensity value changes, the time range over which the laser intensity value continuously changes, and the laser intensity range; The type of the wafer passing through the laser is determined based on a successful matching result between the change condition and the type judgment condition.

7. The wafer status detection method according to claim 6, wherein: The step of matching the changes in the laser intensity values ​​received at the different laser receiving positions with the type judgment conditions corresponding to the different wafer types; and determining the type of the wafer passing through the laser according to a successful matching result between the changes and the type judgment conditions, includes: Constructing a three-dimensional model corresponding to the wafers on each slot in the wafer box according to the changes in the laser intensity values ​​received at the different laser receiving positions; the three-dimensional model is composed of three-dimensional coordinate axes: a position axis representing the laser receiving position, a time axis, and an intensity axis representing the laser receiving intensity; Matching the coordinate ranges of the three-dimensional model corresponding to the target wafer under the three coordinate axes with the type judgment conditions corresponding to different wafer types; wherein the target wafer is a wafer in any slot in the wafer box; The type of the target wafer is determined based on a successful matching result between the coordinate range and the type judgment condition.

8. The wafer status detection method according to claim 6, wherein: The emission direction of the laser is parallel to the wafer that is normally placed and has no warpage in the wafer box; the fixed width of the laser is less than or equal to the diameter of the wafer; the wafer in the loading chamber moves at a constant speed in a direction perpendicular to the emission direction of the laser; When a wafer having a first thickness and a first transparency and having no warpage passes through the laser, the changes in the laser intensity values ​​received at the different laser receiving positions are as follows: the laser intensity values ​​at the different laser receiving positions all change from the initial laser intensity to the first laser intensity corresponding to the first transparency, and the first laser intensity is maintained for a first time before returning to the initial laser intensity; wherein the first time = the first thickness ÷ the movement speed of the wafer; When a wafer having a second thickness, a second transparency and a second warp passes through the laser, the changes in the laser intensity values ​​received at the different laser receiving positions are as follows: there is a laser receiving position where the laser intensity value changes from the initial laser intensity to the second laser intensity corresponding to the second transparency, and based on the second thickness and the second warp, the laser receiving position where the laser intensity value changes gradually changes.

9. The wafer status detection method according to claim 6, wherein: If the type of the wafer cannot be determined, it is determined that the wafer is abnormally placed in the wafer box and is in an abnormal state, specifically including: If the change fails to successfully match the type judgment condition corresponding to the same wafer type, the abnormal placement state of the wafer in the wafer box is determined based on the change in the laser intensity values ​​received at the different laser receiving positions.

10. The wafer status detection method according to claim 9, wherein: The determining, based on changes in laser intensity values ​​received at different laser receiving positions, that the abnormal placement state of the wafer in the wafer box is abnormal, includes: If the change in the laser intensity values ​​received at the different laser receiving positions is that the laser receiving position where the laser intensity changes changes changes along a certain tilt direction, it is determined that the wafer passing through the laser is placed tilted in the wafer box.

11. The wafer status detection method according to claim 9, wherein: The determining, based on changes in laser intensity values ​​received at different laser receiving positions, that the abnormal placement state of the wafer in the wafer box is abnormal, includes: If the change in the laser intensity values ​​received at the different laser receiving positions is: the time for which the laser intensity value continuously changes is greater than the time range included in the type judgment condition corresponding to any wafer type, it is determined that the wafers passing through the laser are overlapped and placed in the wafer box.

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