Device and method for measuring eccentricity of wafer

Abstract

The invention provides a device and a method for measuring wafer eccentricity. The device comprises a plurality of ejector pin supporting seats distributed in the circumferential direction, a plurality of pressure sensors, a plurality of vacuum penetration pieces, a fixed bottom plate and a data processing module. One pressure sensor is arranged at the upper end part of each ejector pin supporting seat; the lower end part of each ejector pin supporting seat is fixed on the fixed bottom plate; the upper end portion of each vacuum through piece is connected with one pressure sensor in a sealed mode, and the lower end portion of each vacuum through piece penetrates through the fixing bottom plate and is connected to the data processing module.

Description

Technical Field

[0001] The invention relates to semiconductor equipment, and in particular to a device and method for measuring wafer eccentricity using a fixed ejector pin. Background Art

[0002] In traditional PECVD equipment, the wafer is placed on a heating plate, and the wafer can be lifted up by a pin under the heating plate to achieve wafer picking and placement. Ideally, the center of the wafer should always coincide with the center of the heating plate, so that the uniformity of thin film deposition can be guaranteed during the process.

[0003] However, in reality, due to various operational errors, the center of the wafer may deviate from the center of the heating plate, causing the two to be non-concentric. In this case, it is necessary to detect the eccentricity of the wafer and accurately detect the eccentricity angle and eccentricity distance in real time. Summary of the invention

[0004] The invention provides a device and a method for measuring wafer eccentricity, which are particularly suitable for measuring wafer eccentricity of a fixed ejector pin.

[0005] The device for measuring wafer eccentricity comprises: a plurality of ejector pin support seats distributed in the circumferential direction, a plurality of pressure sensors, a plurality of vacuum penetration pieces, a fixed bottom plate and a data processing module.

[0006] A pressure sensor is arranged at the upper end of each ejector support seat.

[0007] The lower end of each ejector support seat is fixed on the fixed bottom plate.

[0008] The upper end of each vacuum penetration piece is vacuum-tightly connected to one of the pressure sensors, and the lower end thereof penetrates through the fixed bottom plate and is connected to the data processing module.

[0009] In one embodiment, the device for measuring wafer eccentricity of the present invention further comprises:

[0010] A base having a plurality of through holes;

[0011] A plurality of ejector pins, supporting the wafer placed on the base, wherein each of the ejector pins passes through one of the through holes, and the base can move up and down relative to the ejector pins;

[0012] A plurality of weights, each of which is sleeved on the outer periphery of the lower end of one of the ejector pins.

[0013] In one embodiment, when the lower end of the ejector pin falls onto the upper end of the ejector pin support seat during the descending process, the ejector pin is supported by the ejector pin support seat and no longer moves downward. As the base continues to move downward, the ejector pin lifts up the wafer, and the pressure sensor detects the pressure exerted on it.

[0014] In one embodiment, the upper end of the ejector pin contacts the wafer, and the lower end of the ejector pin is located directly above the ejector pin support seat.

[0015] In one embodiment, the outer diameter of the upper end of the ejector pin is greater than the minimum inner diameter of the through hole, so that the upper end of the ejector pin is stuck on the upper surface of the base.

[0016] In one embodiment, the number of the plurality of ejector pins corresponds to the number of the plurality of ejector pin support seats, the plurality of pressure sensors, and the plurality of vacuum penetration members.

[0017] In one embodiment, the pressure sensor is a piezoelectric ceramic pressure sensor.

[0018] In one embodiment, the pressure sensor transmits the detected signal to the data processing module through the vacuum through-piece to determine in real time whether the wafer is eccentric, and calculates the eccentric angle and eccentric distance of the wafer after determining that the eccentricity exists.

[0019] In one embodiment, determining whether the wafer is eccentric includes:

[0020] The pressure sensor first measures the supporting force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position, and uses the measured force as a standard value;

[0021] The pressure sensor measures the supporting force of the ejector pin after the wafer is lifted up at the actual position of the wafer, and uses the measured force as the actual value;

[0022] The data processing module determines whether the difference between the standard value and the standard value is greater than a preset value. If the difference is greater than the preset value, it is determined that the wafer is eccentric.

[0023] In one embodiment, the data processing module calculates the eccentricity angle and eccentricity distance of the wafer according to the following formula:

[0024]

[0025] in,

[0026]

[0027] in:

[0028] r is the radius of the shape circle where the ejector pin is located;

[0029] G is the total gravity applied to one of the pressure sensors, which is 1 / 3 of the weight of the wafer, the weight of one of the ejector pins, and the weight of a weight sleeved on the lower end of the ejector pin, assuming that there are three ejector pins;

[0030] α is the eccentricity angle;

[0031] L is the eccentric distance;

[0032] They are respectively the supporting forces of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

[0033] The present invention also provides a method for measuring wafer eccentricity, wherein the method is performed using the device for measuring wafer eccentricity of a fixed ejector as described above, and the method includes but is not limited to the following steps:

[0034] The pressure sensor first measures the supporting force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position, and uses the measured force as a standard value;

[0035] The pressure sensor measures the supporting force of the ejector pin after the wafer is lifted up at the actual position of the wafer, and uses the measured force as the actual value;

[0036] The data processing module determines whether the difference between the standard value and the standard value is greater than a preset value. If the difference is greater than the preset value, it is determined that the wafer is eccentric.

[0037] In one embodiment, the method further includes: when the data processing module determines that the wafer is eccentric, calculating the eccentric angle and eccentric distance of the wafer according to the following formula:

[0038]

[0039] in,

[0040]

[0041] in:

[0042] r is the radius of the shape circle where the ejector pin is located;

[0043] G is the total gravity applied to one of the pressure sensors, which is 1 / 3 of the weight of the wafer, the weight of one of the ejector pins, and the weight of a weight sleeved on the lower end of the ejector pin, assuming that there are three ejector pins;

[0044] α is the eccentricity angle;

[0045] L is the eccentric distance;

[0046] They are respectively the supporting forces of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

[0047] The device and method for measuring wafer eccentricity of a fixed ejector pin of the present invention uses a piezoelectric ceramic (such as PZT-5A) pressure sensor, which is fixed on a support base supporting the ejector pin and connected to a data processing module to detect in real time and accurately whether the wafer is eccentric after the ejector pin lifts the wafer, and calculate the angle and distance of the wafer eccentricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above invention content and the following specific embodiments of the present invention will be better understood when read in conjunction with the accompanying drawings. It should be noted that the accompanying drawings are only examples of the claimed invention. In the accompanying drawings, the same reference numerals represent the same or similar elements.

[0049] Figure 1 A device for measuring wafer eccentricity according to an embodiment of the present invention is shown;

[0050] Figure 2 A cross-sectional view showing a device for measuring wafer eccentricity according to an embodiment of the present invention;

[0051] Figure 3 An enlarged cross-sectional view of an ejector pin support seat according to an embodiment of the present invention is shown;

[0052] Figure 4 A general schematic diagram of a device for measuring wafer eccentricity according to an embodiment of the present invention is shown;

[0053] Figure 5A A schematic diagram showing a supporting force measured by a pressure sensor according to an embodiment of the present invention;

[0054] Figure 5B A schematic diagram showing a supporting force measured by a pressure sensor according to an embodiment of the present invention;

[0055] Fig. 6A A top view showing a wafer eccentricity according to an embodiment of the present invention is shown;

[0056] Figure 6B A schematic diagram showing the offset of the wafer center according to an embodiment of the present invention;

[0057] Figure 6C A schematic diagram showing the supporting force measured by a pressure sensor after wafer eccentricity according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0058] The detailed features and advantages of the present invention are described in detail in the specific embodiments below, and the content is sufficient to enable any person skilled in the art to understand the technical content of the present invention and implement it accordingly, and according to the description, claims and drawings disclosed in this specification, those skilled in the art can easily understand the relevant purposes and advantages of the present invention. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this embodiment. On the contrary, the purpose of introducing the invention in conjunction with the embodiment is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, many specific details will be included in the following description. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0059] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0061] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, channels, components, regions, layers and / or parts, these components, channels, components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, channels, components, regions, layers and / or parts. In addition, the terms "first", "second", "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0062] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0063] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0064] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0065] The present invention provides a device for measuring wafer eccentricity for a fixed ejector pin, comprising: a plurality of ejector pin support seats distributed circumferentially, a plurality of pressure sensors, a plurality of vacuum penetration pieces, a fixed bottom plate and a data processing module.

[0066] A pressure sensor is arranged at the upper end of each ejector pin support seat.

[0067] The lower end of each ejector pin supporting seat is fixed on the fixed bottom plate.

[0068] The upper end of each vacuum penetration piece is vacuum-tightly connected to a pressure sensor, and the lower end thereof penetrates through the fixed bottom plate and is connected to the data processing module.

[0069] Figure 1 FIG. 1 shows a device for measuring wafer eccentricity according to an embodiment of the present invention. The device includes a base 101, a pin 102, a weight 103, a pin support seat 104, a fixed bottom plate 105, a pressure sensor 106, a vacuum through piece ( Figure 1 Not shown, Figure 2 ), data processing module ( Figure 1 Not shown, Figure 4 ).

[0070] The base 101 is used to carry and heat the wafer 107. The base 101 has a plurality of through holes corresponding to the number of ejector pins.

[0071] In one embodiment, the base 101 is a heating plate.

[0072] The ejector pin 102 is inserted into the through hole. The outer diameter of the upper end of the ejector pin 102 is larger than the minimum inner diameter of the through hole, so that the upper end of the ejector pin 102 is stuck on the upper surface of the base 101 without falling.

[0073] The upper end of the ejector pin 102 supports the wafer placed on the susceptor 101 .

[0074] The weight 103 is sleeved on the outer periphery of the lower end of the ejector pin 102 .

[0075] The ejector pin support seat 104 is disposed directly below the ejector pin 102 and is used to support the ejector pin 102 .

[0076] The upper end of the ejector support seat 104 is fixed or integrated with a pressure sensor 106, and the lower end is fixed on the fixed bottom plate 105. When the base 101 drives the ejector 102 to descend, when the lower end of the ejector 102 falls to the upper end of the ejector support seat 104, the ejector 102 is held by the ejector support seat 104 and no longer moves downward. As the base 101 continues to move downward, the ejector 102 lifts the wafer 107, and the pressure sensor 106 can detect the pressure on it.

[0077] In one embodiment, the number of ejector pins is three, and the three ejector pins are evenly distributed along the circumferential direction.

[0078] In one embodiment, the pressure sensor 106 is a piezoelectric ceramic pressure sensor, which may be made of PZT-5A material. The advantage of piezoelectric ceramics is that they are highly sensitive and can induce more charges for a small deformation.

[0079] The pressure sensor 106 transmits the signal to a data processing module (not shown) for processing, so as to calculate the supporting force of each ejector pin after lifting the wafer in real time and accurately, thereby determining whether the wafer is eccentric and calculating the eccentric angle and eccentric distance of the wafer.

[0080] Figure 2 FIG. 2 is a cross-sectional view of a device for measuring wafer eccentricity by fixing a pin according to an embodiment of the present invention. Figure 2 As shown, the ejector pin support seat 104 is located below the ejector pin 102. A pressure sensor 106 is integrated at the upper end of the ejector pin support seat 104, and the pressure sensor 106 transmits the measured signal to the data processing module through the vacuum penetration piece 201.

[0081] Figure 3An enlarged cross-sectional view of an ejector support base according to an embodiment of the present invention is shown. The ejector support base 104 is fixed on a fixed base plate 105. A pressure sensor 106 is provided at the upper end of the ejector support base 104. The vacuum penetration piece 201 has an upper end 301 and a lower end 302. The upper end 301 is vacuum-sealed and connected to the pressure sensor 106, and the lower end 302 penetrates the fixed base plate 105 to be exposed to the atmosphere and is connected to an external data processing module through its cable.

[0082] The upper end 301 of the vacuum penetration piece 201 is connected to a high vacuum, and the lower end 302 is connected to the atmosphere. The vacuum penetration piece 201 is mainly used to introduce electrical signals into the high vacuum, while also maintaining a good seal.

[0083] Figure 4 FIG. 2 is a schematic diagram showing an overall structure of a device for measuring wafer eccentricity using a fixed ejector pin according to an embodiment of the present invention. Figure 4 As shown, the external data processing module is connected to the cable at the lower end of the vacuum feedthrough.

[0084] Figure 5A A front view of the wafer support force exerted by a ejector pin support seat measured by a pressure sensor according to an embodiment of the present invention is shown.

[0085] Under normal conditions, the wafer is concentric with the heating plate, and the wafer is adsorbed on the heating plate through electrostatic adsorption, and the overall weight of the ejector pin and the wafer carried by the ejector pin is borne by the ejector pin support seat below.

[0086] In the embodiment of this case, there are three ejector pins: P1, P2, and P3. At this time, the piezoelectric ceramic pressure sensors corresponding to the three ejector pins (P1, P2, and P3) measure the support force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position (i.e., the center of the wafer is concentric with the center of the substrate), and the force is used as the standard value, which is F_P1, F_P2, and F_P3 respectively.

[0087] Figure 5B FIG. 2 shows a cross-sectional view of the support force of the ejector pin support seat on the wafer measured by a pressure sensor according to an embodiment of the present invention. Figure 5B As shown, at this time, the supporting forces after the ejector pins lift up the wafer are measured when the wafer is in a non-eccentric position (that is, the center of the wafer is concentric with the center of the substrate), and are F_P1, F_P2, and F_P3 respectively.

[0088] Fig. 6A FIG. 2 shows a top view of a wafer eccentricity according to an embodiment of the present invention. Fig. 6A As shown, the wafer is still supported by three pins P1, P2, and P3, but the center of the wafer is offset from the normal point O1 to point O2. The enlarged diagram of the offset at the center 601 is shown in Figure 6B shown.

[0089] Figure 6B FIG. 4 is a schematic diagram showing the offset of the wafer center according to an embodiment of the present invention.

[0090] When the wafer is eccentric, for example, its center position is offset from the normal point O1 to the point O2, the offset angle is α (that is, it is rotated by an angle α in the same horizontal plane), and the offset distance is L.

[0091] Figure 6C A schematic diagram showing the supporting force of a wafer on a pin support seat measured by a pressure sensor after the wafer is eccentric according to an embodiment of the present invention.

[0092] In the eccentric state, the supporting forces corresponding to the three ejector pins P1, P2, and P3 are changed from F_P1, F_P2, and F_P3 to F_P1', F_P2', and F_P3', and the changes in the supporting forces corresponding to the three ejector pins are Δ1, Δ2, and Δ3, respectively.

[0093] in:

[0094] Δ1=F_P1'-F_P1,;

[0095] Δ2 = F_P2'-F_P2;

[0096] Δ3 = F_P3'-F_P3;

[0097] When the absolute value of any of the supporting force changes corresponding to the three ejector pins exceeds a certain threshold, such as 1g, it is determined that the wafer has an eccentricity problem.

[0098] Among them, F_P1, F_P2, F_P3; F_P1', F_P2', F_P3' are measured by the pressure sensor, and the calculation and judgment of Δ1, Δ2, Δ3 can be executed by the data processing module.

[0099] According to the moment balance equation, we have:

[0100]

[0101] in:

[0102] r is the radius of the shape circle where the ejector pin is located.

[0103] G is the total gravity applied to a pressure sensor, where the total gravity is 1 / 3 of the wafer weight, the weight of a pin, and the weight of a weight;

[0104] α is the eccentricity angle of the wafer;

[0105] L is the eccentric distance L of the wafer;

[0106] They are respectively the supporting force of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

[0107] According to the above moment balance equation, it can be calculated:

[0108]

[0109] in:

[0110]

[0111] Thus, the eccentricity angle α and eccentricity distance L of the wafer can be obtained.

[0112] In one embodiment, the calculation of the eccentricity angle α and the eccentricity distance L of the wafer may be performed by a data processing module.

[0113] The present invention also provides a method for measuring wafer eccentricity using a fixed ejector pin, the method including but not limited to the following steps:

[0114] The pressure sensor first measures the supporting force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position, and uses the measured force as a standard value;

[0115] The pressure sensor measures the supporting force of the ejector pin after the wafer is lifted up at the actual position of the wafer, and uses the measured force as the actual value;

[0116] The data processing module determines whether the difference between the standard value and the standard value is greater than a preset value, and if it is greater than the preset value, it is determined that the wafer is eccentric;

[0117] When the data processing module determines that the wafer is eccentric, the eccentric angle and eccentric distance of the wafer are calculated according to the following formula:

[0118]

[0119] in,

[0120]

[0121] in:

[0122] r is the radius of the shape circle where the ejector pin is located;

[0123] G is the total gravity applied to one of the pressure sensors, which is 1 / 3 of the weight of the wafer, the weight of one of the ejector pins, and the weight of a weight sleeved on the lower end of the ejector pin, assuming that there are three ejector pins;

[0124] α is the eccentricity angle;

[0125] L is the eccentric distance;

[0126] They are respectively the supporting forces of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

[0127] Those skilled in the art will appreciate that the various illustrative components, modules, blocks, units, circuits, systems, and steps described in conjunction with the embodiments disclosed herein may be implemented by hardware, software (including firmware, resident software, microcode, etc.), or a combination of the two. To clearly illustrate this interchangeability of hardware and software, various illustrative components, modules, blocks, units, circuits, systems, and steps are described above in general terms in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. The technician may implement the described functionality in different ways for each specific application, but such implementation decisions should not be interpreted as resulting in a departure from the scope of the present invention.

[0128] Flowcharts are used in the present application to illustrate the operations or steps performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations or steps are not necessarily performed accurately in order. On the contrary, various operations or steps may be processed in reverse order or simultaneously. At the same time, other operations or steps may be added to these processes, or one or more operations or steps may be removed from these processes.

[0129] Unless explicitly stated in the claims, the order of the processing elements and sequences, the use of alphanumeric characters, or the use of other names described in the present application are not intended to limit the order of the processes and methods of the present application.

[0130] Furthermore, aspects of the present application may take the form of a computer product embodied in one or more computer-readable media including computer-readable program code.

[0131] A computer readable signal medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of forms, including electromagnetic, optical, etc., or a suitable combination. A computer readable signal medium may be any computer readable medium other than a computer readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer readable signal medium may be propagated through any suitable medium, including radio, cable, fiber optic cable, RF, or similar media, or any combination of the above media.

[0132] The computer program coding required for the operation of each part of the application can be written in any one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python, etc., conventional procedural programming languages ​​such as C language, Visual Basic, Fortran 2003, Perl, COBOL 2002, PHP, ABAP, dynamic programming languages ​​such as Python, Ruby and Groovy, or other programming languages, etc. The program coding can be run completely on the user's computer, or run on the user's computer as an independent software package, or run partly on the user's computer and partly on the remote computer, or run completely on the remote computer or server. In the latter case, the remote computer can be connected to the user's computer through any network form, such as a local area network (LAN) or a wide area network (WAN), or connected to an external computer (e.g., via the Internet), or in a cloud computing environment, or used as a service such as software as a service (SaaS).

[0133] Those skilled in the art will appreciate that information, signals, and data may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips cited throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0134] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium may be integrated into a processor. In an alternative, a processor and a storage medium may reside in a user terminal as discrete components.

[0135] In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented as a computer program product in software, each function may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one place to another. Storage media may be any available medium that can be accessed by a computer. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, a server, or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of the medium. Disk and disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, wherein disk often reproduces data magnetically, while disc reproduces data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0136] The terms and expressions used above are for descriptive purposes only, and the present invention should not be limited to these terms and expressions. The use of these terms and expressions does not mean to exclude any equivalent features of the illustrations and descriptions (or parts thereof), and it should be recognized that various modifications that may exist should also be included in the scope of the claims. Other modifications, changes and substitutions may also exist. Accordingly, the claims should be deemed to cover all such equivalents.

[0137] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus facilitate the understanding of one or more embodiments of the invention, in the foregoing description of the embodiments of this application, multiple features are sometimes combined into one embodiment, drawing or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims.

[0138] Similarly, it should be pointed out that although the present invention has been described with reference to the current specific embodiments, ordinary technicians in this technical field should realize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions may be made without departing from the spirit of the present invention. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present invention, they will fall within the scope of the claims of this application.

Claims

1. A device for measuring wafer eccentricity, characterized in that: include: Multiple ejector support seats, multiple pressure sensors, multiple vacuum penetration parts, a fixed base plate and a data processing module distributed in the circumferential direction; A pressure sensor is disposed at the upper end of each ejector support seat; The lower end of each ejector support seat is fixed to the fixed bottom plate; The upper end of each vacuum penetration piece is vacuum-tightly connected to one of the pressure sensors, and the lower end thereof penetrates through the fixed bottom plate and is connected to the data processing module.

2. The device for measuring wafer eccentricity according to claim 1, characterized in that: Also includes: A base having a plurality of through holes; A plurality of ejector pins, supporting the wafer placed on the base, wherein each of the ejector pins passes through one of the through holes, and the base can move up and down relative to the ejector pins; A plurality of weights, each of which is sleeved on the outer periphery of the lower end portion of one of the ejector pins.

3. The device for measuring wafer eccentricity according to claim 2, characterized in that: When the base drives the ejector pin to descend, when the lower end of the ejector pin falls to the upper end of the ejector pin support seat, the ejector pin is supported by the ejector pin support seat and no longer moves downward. As the base continues to move downward, the ejector pin lifts up the wafer, and the pressure sensor detects the pressure exerted on it.

4. The device for measuring wafer eccentricity according to claim 2, characterized in that: The upper end of the ejector pin contacts the wafer, and the lower end of the ejector pin is located directly above the ejector pin supporting seat.

5. The device for measuring wafer eccentricity according to claim 2, characterized in that: The outer diameter of the upper end of the ejector pin is greater than the minimum inner diameter of the through hole, so that the upper end of the ejector pin is stuck on the upper surface of the base.

6. The device for measuring wafer eccentricity according to claim 2, characterized in that: The number of the plurality of ejector pins corresponds to the number of the plurality of ejector pin support seats, the plurality of pressure sensors, and the plurality of vacuum penetration pieces.

7. The device for measuring wafer eccentricity according to claim 1, characterized in that: The pressure sensor is a piezoelectric ceramic pressure sensor.

8. The device for measuring wafer eccentricity according to claim 1, characterized in that: The pressure sensor transmits the detected signal to the data processing module through the vacuum through-piece to determine in real time whether the wafer is eccentric, and calculates the eccentric angle and eccentric distance of the wafer after determining that the eccentricity exists.

9. The device for measuring wafer eccentricity according to claim 8, characterized in that: Determining whether the wafer is eccentric includes: The pressure sensor first measures the supporting force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position, and uses the measured force as a standard value; The pressure sensor measures the supporting force of the ejector pin after the wafer is lifted up at the actual position of the wafer, and uses the measured force as the actual value; The data processing module determines whether the difference between the standard value and the standard value is greater than a preset value. If the difference is greater than the preset value, it is determined that the wafer is eccentric.

10. The device for measuring wafer eccentricity according to claim 8, characterized in that: The data processing module calculates the eccentricity angle and eccentricity distance of the wafer according to the following formula: in, in: r is the radius of the shape circle where the ejector pin is located; G is the total gravity applied to one of the pressure sensors, which is 1 / 3 of the weight of the wafer, the weight of one of the ejector pins, and the weight of a weight sleeved on the lower end of the ejector pin, assuming that there are three ejector pins; α is the eccentricity angle; L is the eccentric distance; They are respectively the supporting forces of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

11. A method for measuring wafer eccentricity, characterized in that: The method is performed using the device for measuring wafer eccentricity as claimed in claim 1, and the method comprises: The pressure sensor first measures the supporting force of the ejector pin after the wafer is lifted up when the wafer is in a non-eccentric position, and uses the measured force as a standard value; The pressure sensor measures the supporting force of the ejector pin after the wafer is lifted up at the actual position of the wafer, and uses the measured force as the actual value; The data processing module determines whether the difference between the standard value and the standard value is greater than a preset value. If the difference is greater than the preset value, it is determined that the wafer is eccentric.

12. The method for measuring wafer eccentricity according to claim 11, characterized in that: Also includes: When the data processing module determines that the wafer is eccentric, the eccentric angle and eccentric distance of the wafer are calculated according to the following formula: in, in: r is the radius of the shape circle where the ejector pin is located; G is the total gravity applied to one of the pressure sensors, which is 1 / 3 of the weight of the wafer, the weight of one of the ejector pins, and the weight of a weight sleeved on the lower end of the ejector pin, assuming that there are three ejector pins; α is the eccentricity angle; L is the eccentric distance; They are respectively the supporting forces of the ejector pin after the wafer is lifted up, measured by the pressure sensor at the actual position of the wafer.

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