Device and method for locating wafer orientation

Abstract

The present invention belongs to the field of semiconductor technology, and discloses a device and method for locating the direction of a wafer, wherein the device for locating the direction of the wafer includes a wafer stage, a probe, a pressure component, and a detection component. The device for locating the direction of the wafer contacts the wafer through the probe, and monitors the displacement of the metal sheet on the probe through the detection component. Once the probe contacts the notch of the wafer and the metal sheet deflects, the position of the notch on the wafer can be immediately determined, and then the direction of the wafer can be located. The device has a simple structure and low cost, and can be effectively used even when facing a transparent wafer. The method for locating the direction of the wafer based on the above-mentioned device for locating the direction of the wafer uses a direct contact method to locate the notch. Compared with the photoelectric sensing detection method, it can still be effectively used when facing a transparent wafer, and the operation is simple and the positioning is accurate.

Description

Technical Field

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

[0002] In the semiconductor industry, all wafers have a "feature". On 8-inch and 12-inch wafers, this "feature" is mostly a notch. All fully automatic semiconductor equipment needs to have a device that can locate the notch or flat edge of the wafer to determine the current direction of the wafer. Such a device is called a pre-alignment device, or PA for short.

[0003] The mainstream PAs on the market currently use photoelectric sensing to detect the position of the notch and flat. The angle of the notch and flat on the wafer is determined by the signal change of the photoelectric sensor when the laser scans the notch or flat, thereby judging the current direction of the wafer. However, in order for the photoelectric sensor to receive changes in the light signal, the wafer itself must have a certain light shielding ability. In other words, when the wafer is completely transparent or partially transparent, the photoelectric sensor cannot detect obvious changes in laser intensity when the laser scans the notch, and cannot accurately find the position of the notch. Therefore, the disadvantage of this solution is that it cannot be used to locate transparent wafers. Summary of the invention

[0004] The object of the present invention is to provide a device and method for locating the direction of a wafer, so as to solve the problem that the existing photoelectric sensing detection method cannot locate the transparent wafer.

[0005] To achieve the above object, on the one hand, the present invention adopts the following technical solutions:

[0006] A device for locating a wafer direction, comprising:

[0007] The wafer stage is used to carry the wafer and drive the wafer to rotate around its own center of circle. A notch is set on the edge of the wafer.

[0008] The probe is located on one side of the wafer stage, the needle head of the probe is used to contact the edge of the wafer, and the needle tail of the probe is provided with a metal sheet;

[0009] A pressure-applying assembly, used to drive the needle tip of the probe to keep in contact with the edge of the wafer;

[0010] The detection component includes two capacitor plates arranged in parallel and spaced apart, the two capacitor plates are connected to a signal collector, and a metal sheet is arranged between the two capacitor plates. When the needle tip of the probe contacts a non-notch position on the edge of a wafer, the metal sheet is located in the middle of the two capacitor plates, and the electrical signal collected by the signal collector is constant; when the needle tip of the probe contacts a notch in the wafer, the metal sheet is deflected between the two capacitor plates, and the electrical signal collected by the signal collector changes, thereby determining the position of the notch on the wafer.

[0011] As an optional solution, the wafer carrier is driven by a rotary motor. When the electrical signal collected by the signal collector changes, the rotation angle of the rotary motor's shaft from the rotation origin is recorded to achieve positioning and adjust the direction of the wafer.

[0012] As an optional solution, the pressure-applying assembly includes an electromagnetic coil and a metal pressure piece inserted in the electromagnetic coil. The electromagnetic coil generates an axial force on the metal pressure piece to push the needle of the probe toward the wafer.

[0013] As an optional solution, a linear module is disposed on one side of the wafer carrier, a slide seat that can move relative to the wafer is disposed on the linear module, and a middle part of the probe is rotatably disposed on the slide seat.

[0014] As an optional solution, a cross spring is arranged between the probe and the slide seat, and the cross spring is used to provide elastic force to reset the probe.

[0015] The beneficial effects of the present invention are as follows: the device for locating the direction of a wafer contacts the wafer through a probe, and monitors the displacement of a metal sheet on the probe through a detection component; once the probe contacts the notch of the wafer and the metal sheet deflects, the position of the notch on the wafer can be immediately determined, thereby locating the direction of the wafer; the device has a simple structure and low cost, and can be effectively used even when facing transparent wafers.

[0016] On the other hand, the present invention adopts the following technical solutions:

[0017] A method for locating the direction of a wafer, based on the above-mentioned device for locating the direction of a wafer, comprises the steps of:

[0018] Step 1: Concentrically mount the wafer on the wafer stage;

[0019] Step 2: The pressure component applies pressure to the probe, so that the probe tip contacts the non-notch position on the edge of the wafer and the metal sheet is located in the middle of the two capacitor plates, and the signal collector collects the first electrical signal;

[0020] Step three, drive the wafer carrier to rotate, and the probe tip slides across the edge of the wafer. When the signal collector collects a second electrical signal different from the first electrical signal, the metal sheet deflects between the two capacitor plates, that is, the probe tip contacts the notch of the wafer, thereby locating the direction of the wafer.

[0021] As an option, the distance from the probe to the wafer stage is adjustable to accommodate wafers of different sizes.

[0022] Beneficial effects of the present invention: The method for locating the direction of the wafer uses a direct contact method to locate the notch. Compared with the photoelectric sensing detection method, it can still be effectively used when facing a transparent wafer, is simple to operate, and has accurate positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of a device for locating the direction of a wafer provided by an embodiment of the present invention.

[0024] Figure 2 It is a top view of a device for locating the direction of a wafer provided by an embodiment of the present invention.

[0025] In the attached figure:

[0026] 1. Wafer stage; 11. Rotating motor;

[0027] 2. Probe; 21. Metal sheet;

[0028] 3. Pressure component; 31. Electromagnetic coil; 32. Metal pressure piece;

[0029] 4. Detection component; 41. Capacitor plate;

[0030] 5. Linear module; 51. Slide seat;

[0031] 6. Cross spring;

[0032] 7. Wafer; 71. Notch. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0037] See also Figure 1 and Figure 2 As shown, this preferred embodiment provides a device for locating the direction of a wafer, comprising a wafer stage 1, a probe 2, a pressure component 3 and a detection component 4, wherein:

[0038] The wafer stage 1 is used to carry the wafer 7 and drive the wafer 7 to rotate around its own center. A notch 71 is provided on the edge of the wafer 7. It should be noted that the notch 71 here is a positioning mark of the wafer 7, not a defect;

[0039] The probe 2 is located at one side of the wafer stage 1, the needle head of the probe 2 is used to contact the edge of the wafer 7, and the needle tail of the probe 2 is provided with a metal sheet 21;

[0040] The pressure-applying component 3 is used to drive the needle tip of the probe 2 to keep in contact with the edge of the wafer 7;

[0041] The detection component 4 includes two capacitor plates 41 arranged in parallel and spaced apart from each other. The two capacitor plates 41 are connected to a signal collector, and the metal sheet 21 is disposed between the two capacitor plates 41 .

[0042] When the needle tip of the probe 2 contacts the non-notch position on the edge of the wafer 7, the metal sheet 21 is located in the middle of the two capacitor plates 41, and the electrical signal collected by the signal collector is constant;

[0043] When the needle tip of the probe 2 contacts the notch 71 of the wafer 7 , the metal sheet 21 is deflected between the two capacitor plates 41 , and the electrical signal collected by the signal collector changes, thereby determining the position of the notch 71 on the wafer 7 .

[0044] Therefore, the probe 2 contacts the wafer 7, and the detection component 4 monitors the displacement of the metal sheet 21 on the probe 2. Once the probe 2 contacts the notch 71 of the wafer 7, the metal sheet 21 deflects, and the position of the notch 71 on the wafer 7 can be immediately determined, thereby locating the direction of the wafer 7. The device has a simple structure and low cost, and can be effectively used even when facing a transparent wafer 7.

[0045] Optionally, the wafer carrier 1 is driven to rotate by a rotating motor 11. When the electrical signal collected by the signal collector changes, the rotation angle of the rotating motor 11 from the rotation origin is recorded to achieve positioning and adjust the direction of the wafer 7.

[0046] Optionally, the pressure component 3 includes an electromagnetic coil 31 and a metal pressure piece 32 inserted in the electromagnetic coil 31. The metal pressure piece 32 generates an axial force from the electromagnetic coil 31 to push the needle of the probe 2 toward the wafer 7. The metal pressure piece 32 generates a thrust under the action of the electromagnetic force, and the direction is Figure 2 The probe 2 is pushed to the right, and the metal sheet 21 is deflected to the left until the needle tip of the probe 2 is stably in contact with the edge of the wafer 7. The needle tip of the probe 2 is subjected to a leftward force and is balanced with the thrust of the metal pressure piece 32, and the position of the metal sheet 21 is also stabilized.

[0047] Optionally, a linear module 5 is provided on one side of the wafer stage 1, and a slide 51 is provided on the linear module 5 that can move relative to the wafer 7, and the middle part of the probe 2 is rotatably provided on the slide 51. Since the driving displacement of the probe 2 by the pressure component 3 is small, when facing wafers 7 of different sizes, a large displacement of the probe 2 is achieved through the linear module 5, so that no matter the size of the wafer 7 is 12 inches, 8 inches, 6 inches, 4 inches or other non-standard sizes, the device can be compatible, and there is no need to select the size of the wafer 7 in advance.

[0048] Optionally, a cross spring 6 is provided between the probe 2 and the slide 51, and the cross spring 6 is used to provide elastic force to reset the probe 2. The cross spring 6 realizes a function similar to a bearing, and while realizing the rotation connection of the probe 2, it gives a certain force to the probe 2, and drives the probe 2 to reset when the probe 2 is not in contact with the wafer 7 and the electromagnetic coil 31 is powered off, and at this time the metal sheet 21 is also reset to the center.

[0049] In this regard, this embodiment further provides a method for locating the direction of a wafer, based on the above-mentioned device for locating the direction of a wafer, comprising the steps of:

[0050] Step 1: Concentrically mount the wafer 7 on the wafer stage 1;

[0051] Step 2, the pressure component 3 applies pressure to the probe 2, specifically, the electromagnetic coil 31 is energized to give electromagnetic force to the metal pressure piece 32, and the metal pressure piece 32 pushes the probe 2 so that the needle tip of the probe 2 contacts the non-notch position on the edge of the wafer 7. At this time, the force on the contact surface of the probe 2 is balanced with the thrust of the metal pressure piece 32, the probe 2 remains stable, and the metal sheet 21 is located in the middle of the two capacitor plates 41. At this time, the signal collector collects a constant first electrical signal;

[0052] Step 3: Drive the wafer stage 1 to rotate, and the needle tip of the probe 2 passes over the edge of the wafer 7. When the signal collector collects a second electrical signal different from the first electrical signal, the metal sheet 21 deflects between the two capacitor plates 41, indicating that the needle tip of the probe 2 is in contact with the notch 71 of the wafer 7. The reason is that when the probe 2 is scratched at the notch 71, the contact force on the needle tip of the probe 2 becomes smaller, and loses balance with the thrust of the metal pressure piece 32, and then the metal sheet 21 deflects (in the direction of Figure 2 The position of the different electrical signals is the position of the notch 71 on the wafer 7, thereby locating the direction of the wafer 7.

[0053] Therefore, the notch 71 of the wafer 7 is positioned by direct contact. Compared with the photoelectric sensing detection method, it can still be effectively used when facing a transparent wafer 7, and has simple operation and accurate positioning.

[0054] Optionally, the distance between the probe 2 and the wafer stage 1 is adjustable to be suitable for wafers 7 of different sizes, which is specifically achieved by adding a linear module 5 .

[0055] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A device for locating the direction of a wafer, characterized in that: include: A wafer carrier (1) is used for carrying a wafer (7) and driving the wafer (7) to rotate around its own center of circle, and a notch (71) is provided on the edge of the wafer (7); A probe (2) is located on one side of the wafer carrier (1); the needle head of the probe (2) is used to contact the edge of the wafer (7); and the needle tail of the probe (2) is provided with a metal sheet (21); A pressure-applying component (3) for driving the needle tip of the probe (2) to maintain contact with the edge of the wafer (7); The detection component (4) comprises two capacitor plates (41) arranged in parallel and spaced apart, the two capacitor plates (41) being connected to a signal collector, the metal sheet (21) being arranged between the two capacitor plates (41), and when the needle tip of the probe (2) contacts a non-notch position on the edge of the wafer (7), the metal sheet (21) is located in the middle of the two capacitor plates (41), and the electrical signal collected by the signal collector is constant; when the needle tip of the probe (2) contacts the notch (71) of the wafer (7), the metal sheet (21) is deflected between the two capacitor plates (41), and the electrical signal collected by the signal collector changes, thereby determining the position of the notch (71) on the wafer (7).

2. The device for locating the direction of a wafer according to claim 1, characterized in that: The wafer carrier (1) is driven to rotate by a rotating motor (11); when the electrical signal collected by the signal collector changes, the rotation angle of the rotating shaft of the rotating motor (11) from the rotation origin is recorded to achieve positioning and adjust the direction of the wafer (7).

3. The device for locating the direction of a wafer according to claim 1, characterized in that: The pressure-applying assembly (3) comprises an electromagnetic coil (31) and a metal pressure-applying member (32) inserted into the electromagnetic coil (31); the metal pressure-applying member (32) is driven by an axial force generated by the electromagnetic coil (31) to push the needle of the probe (2) toward the wafer (7).

4. The device for locating the direction of a wafer according to claim 1, characterized in that: A linear module (5) is arranged on one side of the wafer carrier (1); a slide seat (51) movable relative to the wafer (7) is arranged on the linear module (5); and a middle part of the probe (2) is rotatably arranged on the slide seat (51).

5. The device for locating the direction of a wafer according to claim 4, characterized in that: A cross spring (6) is provided between the probe (2) and the slide seat (51), and the cross spring (6) is used to provide an elastic force for resetting the probe (2).

6. A method for locating the direction of a wafer, based on the device for locating the direction of a wafer according to any one of claims 1 to 5, characterized in that: Includes steps: Step 1: concentrically mounting the wafer (7) on the wafer carrier (1); Step 2, the pressure-applying component (3) applies pressure to the probe (2), so that the needle tip of the probe (2) contacts the non-notch position on the edge of the wafer (7), and the metal sheet (21) is located in the middle of the two capacitor plates (41), and at this time, the signal collector collects a first electrical signal; Step three, drive the wafer carrier (1) to rotate, and the needle tip of the probe (2) passes over the edge of the wafer (7). When the signal collector collects a second electrical signal different from the first electrical signal, the metal sheet (21) is deflected between the two capacitor plates (41), that is, the needle tip of the probe (2) contacts the notch (71) of the wafer (7), thereby locating the direction of the wafer (7).

7. The method for locating the direction of a wafer according to claim 6, characterized in that: The distance between the probe (2) and the wafer carrier (1) is adjustable to be suitable for wafers (7) of different sizes.

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