Wafer gap positioning device
Through the combination of light emitter, light receiver and light intensity regulator, the problem of inaccurate positioning of transparent or translucent wafers is solved, efficient wafer angle adjustment and machine error rate reduction is achieved.
Patent Information
- Application Number
- CN202422148175.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-02
AI Technical Summary
The prior art is difficult to accurately locate the gaps in transparent or translucent wafers, resulting in wafer angle adjustment errors and affecting subsequent process flow.
Using a combination of light emitter, light receiver and light intensity regulator, the wafer position is identified by adjusting the light intensity to ensure that the light receiver is turned on or off in the correct position and cannot be turned on in the wrong position.
It improves the accuracy of wafer positioning, reduces the machine error rate, and achieves accurate positioning of transparent or translucent wafers.
Smart Images
Figure CN223092849U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of semiconductors, and particularly to a wafer notch positioning device. Background Art
[0002] At present, the 8-inch machine for wafer acceptance test (WAT) in the factory needs to support the test of 6-inch silicon carbide wafers. However, the sensors used in the existing machines are infrared sensors. The infrared light source will identify the size of the wafer on the sub-chuck, and then realize the positioning of the wafer angle by rotation.
[0003] However, silicon carbide is usually a transparent or semi-transparent silicon wafer. The light source often penetrates through the wafer itself, and the receiver cannot receive the correct feedback, resulting in system errors or the wafer angle being considered to have been adjusted to the optimal state and can be transferred to the chuck for alignment. However, the actual wafer is not adjusted or misadjusted on the sub-chuck, further leading to frequent alignment errors.
[0004] Therefore, how to accurately position the notch of a transparent or semi-transparent wafer is a problem that needs to be solved at present. Summary of the Invention
[0005] The technical problem to be solved by the utility model is how to accurately position the notch of a transparent or semi-transparent wafer, and a wafer notch positioning device is provided.
[0006] To solve the above problems, the utility model provides a wafer notch positioning device. The wafer is a transparent or semi-transparent wafer with a notch, including: a wafer stage for carrying the wafer, the wafer stage having a first side and a second side arranged oppositely; a light emitter located on the first side of the wafer stage for emitting outgoing light to the wafer, the outgoing light emitted by the light emitter being able to pass through the notch when the wafer is adjusted to the correct position; a light receiver located on the second side of the wafer stage for receiving the outgoing light emitted by the light emitter, the light receiver being able to be turned on or off when the light intensity of the received outgoing light is greater than or equal to a preset threshold; a light intensity regulator located between the light emitter and the light receiver, the light intensity regulator being able to adjust the light intensity of the outgoing light so that the light intensity of the outgoing light passing through the notch of the wafer and adjusted by the light intensity regulator is greater than or equal to the preset threshold.
[0007] In some embodiments, the orthographic projections of the light emitter and the light receiver on the wafer stage coincide.
[0008] In some embodiments, the light emitter and the light receiver are a pair of infrared sensors.
[0009] In some embodiments, the light emitter and the light receiver are a pair of laser sensors.
[0010] In some embodiments, the light intensity regulator is disposed at the receiving end of the light receiver, or the light intensity regulator is disposed at the emitting end of the light emitter.
[0011] In some embodiments, the light intensity regulator is a translucent glass.
[0012] In some embodiments, the surface of the translucent glass is rough and contains impurities or bubbles inside.
[0013] In some embodiments, it further includes a jammer which can emit outgoing light different from that of the light emitter to reduce the light intensity of the outgoing light emitted by the light emitter.
[0014] In some embodiments, the notch is located at the edge of the wafer for positioning the angular position of the wafer.
[0015] In some embodiments, the wafer stage can rotate to adjust the angular position of the wafer.
[0016] In the above technical solution, by providing a light intensity regulator between the light emitter and the light receiver, the light intensity of the outgoing light passing through the light intensity regulator is weakened. When the transparent or translucent wafer rotates to the correct position, the outgoing light only passes through the light intensity regulator. Although the light intensity is weakened, it can still turn on or off the light receiver. When the transparent or translucent wafer does not rotate to the correct position, the outgoing light passes through the wafer and the light intensity regulator, and the light intensity after being weakened twice cannot turn on or off the light receiver, thereby achieving the purpose of identifying whether the transparent or translucent wafer is adjusted to the correct position.
[0017] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present invention. Technologies, methods and devices known to those of ordinary skill in the relevant field may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the authorization specification. Description of the Drawings
[0018] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following will briefly introduce the drawings required for use in the description of the specific embodiments. Obviously, the drawings in the following description are only some specific embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0019] Figure 1 It is a side view of a wafer positioning device.
[0020] Figure 2 It is a top-down developed view of the components of the wafer positioning device.
[0021] Figure 3 It is a schematic diagram of the emitted light passing through the wafer when the wafer positioning device positions a transparent or semi-transparent wafer.
[0022] Figure 4 It is a schematic structural diagram of an embodiment of the wafer notch positioning device of the present invention.
[0023] Figure 5 It is a state diagram of the emitted light passing through the wafer in an embodiment of the wafer notch positioning device of the present invention.
[0024] Figure 6 It is a schematic diagram of a transparent or semi-transparent wafer with a notch. Detailed implementation manners
[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.
[0026] Please refer to Figures 1 to 3 , wherein, Figure 1 is a side view of a wafer positioning device, Figure 2 is a top-down developed view of the components of the wafer positioning device, Figure 3 is a schematic diagram of the emitted light passing through the wafer when the wafer positioning device positions a transparent or semi-transparent wafer. As Figures 1 to 2As shown, the wafer positioning device includes a sub-chuck 11, an infrared emitter 12, and an infrared receiver 13. An opaque wafer 19 is located on the surface of the sub-chuck 11, and the opaque wafer 19 rotates under the drive of the sub-chuck 11 to adjust the angular position of the opaque wafer 19. The infrared emitter 12 is located above the sub-chuck 11, and the infrared receiver 13 is located below the sub-chuck 11 and is disposed opposite to the infrared emitter 12. When the opaque wafer 19 is adjusted to the correct angular position, the infrared light emitted by the infrared emitter 12 passes through the notch 190 of the opaque wafer 19 and is received by the infrared receiver 13, and the wafer positioning device determines that the opaque wafer 19 is located at the correct angular position; when the opaque wafer 19 is not adjusted to the correct angular position, the infrared light emitted by the infrared emitter 12 is blocked by the opaque wafer and cannot be received by the infrared receiver 13, and the wafer positioning device determines that the opaque wafer 19 needs to adjust the angular position.
[0027] However, when the wafer positioning device is used to position a transparent or semi-transparent wafer, such as Figure 3 as shown, when the transparent wafer 39 is not adjusted to the correct angular position, the infrared light emitted by the infrared emitter 12 passes through the transparent wafer 39 and is received by the infrared receiver 13, and the wafer positioning device determines that the transparent wafer 39 is located at the correct angular position, while in fact the transparent wafer 39 is not adjusted or is incorrectly adjusted, thus causing an adverse effect on subsequent processes.
[0028] In view of the above phenomenon, the researchers studied the working principle of the receiver and found that when the receiver receives the infrared light source and reaches saturation during the rotation of the wafer, the system will think that the notch has been found, and then calculate the center point according to the shape and structure of the notch and complete the fine adjustment. Therefore, the present invention proposes a wafer notch positioning device, which can appropriately weaken the light intensity of the infrared light source or increase the threshold of the receiver. When rotating to the actual notch, the receiver is normally turned on or off, and when rotating to other edges, even if the infrared light penetrates the transparent wafer, the light intensity cannot reach the threshold of the receiver and the receiver cannot be turned on or off, so that the problem of wafer offset can be solved.
[0029] Please refer to Figures 4 to 6 , in which Figure 4 is a schematic structural diagram of an embodiment of the wafer notch positioning device of the present invention, Figure 5 is a state diagram of the outgoing light of an embodiment of the wafer notch positioning device of the present invention passing through the wafer, Figure 6 is a schematic diagram of a transparent or semi-transparent wafer with a notch. Compared with Figure 5 , Figure 4 simultaneously shows the state of the outgoing light of the wafer notch positioning device of the present invention passing through the notch of the wafer. AsFigure 6 As shown, the wafer 60 is a transparent or semi-transparent wafer with a notch 61, such as Figures 4 to 5 As shown, the wafer notch positioning device includes: a wafer stage 41, a light emitter 42, a light receiver 43, and a light intensity regulator 44. The wafer stage 41 is used to carry the wafer 60, and the wafer stage 41 has a first side and a second side that are oppositely arranged. The light emitter 42 is located on the first side of the wafer stage 41 and is used to emit outgoing light to the wafer 49. The outgoing light emitted by the light emitter 42 can pass through the notch 61 when the wafer 60 is adjusted to the correct position. The light receiver 43 is located on the second side of the wafer stage 41 and is used to receive the outgoing light emitted by the light emitter 42. The light receiver 43 can be turned on or off when the light intensity of the received outgoing light is greater than or equal to a preset threshold. The light intensity regulator 44 is located between the light emitter 42 and the light receiver 43, and the light intensity regulator 44 can adjust the light intensity of the outgoing light so that the light intensity of the outgoing light passing through the notch 61 of the wafer 60 and adjusted by the light intensity regulator 44 is greater than or equal to the preset threshold.
[0030] In the above technical solution, by providing a light intensity regulator between the light emitter and the light receiver, the light intensity of the outgoing light adjusted by the light intensity regulator is weakened. When the transparent or semi-transparent wafer rotates to the correct position, the outgoing light passes through the notch of the wafer. Only through the adjustment of the light intensity regulator, although the light intensity is weakened, the light receiver can still be turned on or off. When the transparent or semi-transparent wafer is not rotated to the correct position, the outgoing light passes through the wafer and the light intensity regulator, and the light intensity after double weakening cannot turn on or off the light receiver, thereby achieving the purpose of identifying whether the transparent or semi-transparent wafer is adjusted to the correct position.
[0031] In some embodiments, the first side of the wafer stage 41 is the side for carrying the wafer 60, that is, the side facing the wafer 60; the second side of the wafer stage 41 is the side facing away from the wafer 60. The orthographic projections of the light emitter 42 and the light receiver 43 on the wafer stage 41 coincide.
[0032] In some embodiments, the light emitter 42 and the light receiver 43 are a pair of infrared sensors, and the outgoing light is infrared light. In other embodiments, the light emitter 42 and the light receiver 43 can also be a pair of laser sensors 43.
[0033] In some embodiments, the light intensity regulator 44 is a semi-transparent glass, and the semi-transparent glass is disposed in front of the light receiver 43.
[0034] In some embodiments, the surface of the translucent glass is rough and contains impurities or bubbles inside. When infrared light passes through the translucent glass, the molecules and atoms in the translucent glass have the ability to absorb the energy of the infrared light. Although most of the infrared light can pass through the translucent glass, the impurities, bubbles and surface roughness in the translucent glass will scatter the infrared light, dispersing its energy in all directions, thereby reducing the transmission efficiency of the infrared light. The surface roughness will cause the infrared light to be reflected and scattered on the surface of the translucent glass. According to the absorption and scattering characteristics of the translucent glass for the infrared light, the light intensity is further weakened, so that the light intensity of the infrared light passing only through the translucent glass can turn on the photoreceiver 43, and the light intensity of the infrared light doubly weakened by passing through the translucent glass and the wafer 60 cannot turn on the photoreceiver 43.
[0035] As Figure 4 shown, when the wafer 60 is adjusted to the correct position, the emitted light emitted by the light emitter 41 passes vertically downward through the notch 61 and is reflected and scattered on the surface of the translucent glass. The light intensity of the emitted light passing through the translucent glass is weakened, and the light intensity of the weakened emitted light can still turn on the photoreceiver 43, thereby determining that the position of the wafer 60 is correct.
[0036] As Figure 5 shown, when the wafer 60 is not adjusted to the correct position, the emitted light emitted by the light emitter 41 passes vertically downward through the wafer 60. The light intensity of the emitted light is weakened when passing through the transparent or translucent wafer 60 and is reflected and scattered when passing through the translucent glass, further weakening the light intensity of the emitted light. The light intensity of the emitted light doubly weakened cannot turn on the photoreceiver 43, thereby determining that the wafer 60 is not adjusted to the correct position and the angular position of the wafer 61 needs to be further adjusted.
[0037] In some embodiments, a jammer (not shown) is included. The jammer can emit emitted light different from that of the light emitter 41 to reduce the light intensity of the emitted light emitted by the light emitter 41. In some embodiments, the emitted light emitted by the light emitter 41 is infrared light, and the emitted light emitted by the jammer is visible light. By using other light sources to interfere with the light intensity of the infrared light, the effect that the light intensity of the infrared light passing through the notch 61 can turn on the photoreceiver 43 and the light intensity of the infrared light passing through the wafer 60 cannot turn on the photoreceiver 43 can also be achieved. In other embodiments, the light intensity of the emitted light passing through the notch 61 can turn on the photoreceiver 43 and the light intensity of the emitted light passing through the wafer 60 cannot turn on the photoreceiver 43 can also be achieved by optimizing system parameters, reducing the receiving parameters of the photoreceiver 43 or adjusting the light-emitting parameters of the light emitter 41.
[0038] As Figure 6 shown, in some embodiments, the wafer 60 is a 6-inch silicon carbide. The notch 61 is located at the edge of the wafer 60 and is used to position the angular position of the wafer 60.
[0039] In some embodiments, the carrier stage 41 can rotate to adjust the angular position of the wafer 60. In this embodiment, the carrier stage 41 is a sub-chuck. After the wafer 60 is adjusted to the correct position, it is transferred to the chuck for alignment.
[0040] As described above, the present utility model weakens the light intensity by adding a light intensity regulator, which has been basically achieved in actual operation. The error reporting rate of the machine tool has been reduced by about 90%, and the 8-inch machine tool can be used to test the 6-inch silicon carbide.
[0041] It should be noted that in the specification, the reference to "an embodiment", "embodiment", "exemplary embodiment", "some embodiments", etc. indicates that the described embodiment may include specific features, structures or characteristics, but each embodiment may not necessarily include the specific feature, structure or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure or characteristic is described in connection with an embodiment, whether or not explicitly described, implementing such a feature, structure or characteristic in combination with other embodiments is within the knowledge of those skilled in the relevant art.
[0042] Generally, the meaning of a term can be at least partially understood from its usage in context. For example, as used herein, the term "one or more" depends at least in part on context and can be used to describe any feature, structure or characteristic in a singular sense or can be used to describe a combination of features, structures or characteristics in a plural sense. Similarly, depending at least in part on context, terms such as "a", "certain" or "the" can also be understood to express a singular usage or a plural usage. Additionally, the term "based on" can be understood to not necessarily be intended to express a set of exclusive factors, but rather can alternatively, also depending at least in part on context, allow for the existence of other factors that may not be explicitly described. It should also be noted in this specification that "connected / coupled" not only refers to a component being directly coupled to another component, but also refers to a component being indirectly coupled to another component through an intermediate component.
[0043] It should be noted that the terms "including" and "having" and their variants involved in the documents of the present utility model are intended to cover non-exclusive inclusion. The terms "first", "second", etc. are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. Unless clearly indicated in the context, it should be understood that the data used in this way can be interchanged under appropriate circumstances. In addition, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other. Furthermore, in the above description, the description of well-known components and technologies is omitted to avoid unnecessarily confusing the concept of the present utility model. In each of the above embodiments, the key point of each embodiment is to illustrate the differences from other embodiments. For the same / similar parts between the embodiments, reference can be made to each other.
[0044] The above is only the preferred embodiment of the present utility model. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present utility model.
Claims
1. A wafer notch positioning device, wherein the wafer is a transparent or semi-transparent wafer with a notch, characterized in that, Comprising: A wafer stage for holding the wafer, the wafer stage having a first side and a second side disposed opposite to each other; An optical emitter located on the first side of the wafer stage for emitting outgoing light towards the wafer, the outgoing light emitted by the optical emitter being capable of passing through the notch when the wafer is adjusted to the correct position; An optical receiver located on the second side of the wafer stage for receiving the outgoing light emitted by the optical emitter, the optical receiver being capable of being turned on or off when the light intensity of the received outgoing light is greater than or equal to a preset threshold; An optical intensity regulator located between the optical emitter and the optical receiver, the optical intensity regulator being capable of adjusting the light intensity of the outgoing light so that the light intensity of the outgoing light passing through the notch of the wafer and adjusted by the optical intensity regulator is greater than or equal to the preset threshold.
2. The wafer notch positioning device according to claim 1, wherein The orthographic projections of the optical emitter and the optical receiver on the wafer stage coincide.
3. The wafer notch positioning device according to claim 1, wherein The optical emitter and the optical receiver are a pair of infrared sensors.
4. The wafer notch positioning device according to claim 1, wherein The optical emitter and the optical receiver are a pair of laser sensors.
5. The wafer notch positioning device according to claim 1, characterized in that, The optical intensity regulator is disposed at the receiving end of the optical receiver, or the optical intensity regulator is disposed at the emitting end of the optical emitter.
6. The wafer notch positioning device according to claim 1, wherein The optical intensity regulator is a translucent glass.
7. The wafer notch positioning device according to claim 6, characterized in that, The surface of the translucent glass is rough and contains impurities or bubbles inside.
8. The wafer notch positioning device according to claim 1, characterized in that, Further comprising a jammer capable of emitting outgoing light different from that of the optical emitter to reduce the light intensity of the outgoing light emitted by the optical emitter.
9. The wafer notch positioning device according to claim 1, wherein The notch is located at the edge of the wafer for positioning the angular position of the wafer.
10. The wafer notch positioning device according to claim 9, characterized in that, The wafer stage is capable of rotating to adjust the angular position of the wafer.