Optical alignment device, optical alignment method, and storage medium

Abstract

The present invention provides an optical alignment device, an optical alignment method, and a computer readable storage medium. The optical alignment device comprises a microscope objective, a first camera, a second camera, an infrared light source, and a controller. A first end of the microscope objective faces a first sample and a second sample to be aligned. The first camera is aligned with a second end of the microscope objective by means of a first semi-reflective and semi-transmissive mirror. The second camera is aligned with the second end of the microscope objective by means of a first reflecting mirror and the first semi-reflective and semi-transmissive mirror. The infrared light source is configured to provide, to the first end of the microscope objective, infrared light passing through the first sample and / or the second sample. In the present invention, a wafer is aligned with a chip by using one microscope objective, so that large horizontal movement of the chip after positioning can be avoided, and the precision of alignment between the wafer and the chip and whether bubbles are present on a bonding surface can be directly detected, so as to improve the quality of bonding between the wafer and the chip.

Description

Optical alignment device, optical alignment method and storage medium Technical Field

[0001] The present invention relates to the field of semiconductor device processing, and in particular to an optical alignment device, an optical alignment method, and a computer-readable storage medium. Background Art

[0002] During semiconductor device processing, the bonding process between wafers and chips is crucial. Prior to bonding, semiconductor processing equipment must align the wafer and chip. A common alignment method involves positioning the wafer and chip using two separate optical microscopes. However, the positioned chip still requires significant horizontal movement to complete the bonding process. Consequently, the mechanical movement involved in this method increases alignment errors and affects bonding accuracy. Furthermore, existing semiconductor processing equipment requires additional detection modules to monitor bonding accuracy and detect bubbles on the bonding surface.

[0003] In order to overcome the above-mentioned defects of the prior art, the art urgently needs an improved optical alignment device to avoid large horizontal movement of the chip after positioning, and to directly detect the alignment accuracy of the wafer and the chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and the chip.

[0004] Summary of the Invention

[0005] The following is a brief summary of one or more aspects to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceivable aspects and is neither intended to identify key or critical elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that will be provided later.

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides an optical alignment device, an optical alignment method and a computer-readable storage medium, which can align the wafer and chip by sharing a microscope objective lens, thereby avoiding large horizontal movement of the chip after positioning, and can directly detect the alignment accuracy of the wafer and chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and chip.

[0007] Specifically, the optical alignment device provided according to the first aspect of the present invention includes a microscope objective lens, a first camera, a second camera, an infrared light source, and a controller. The first end of the microscope objective lens faces the first sample and the second sample to be aligned. The first camera is aligned with the second end of the microscope objective lens via a first half-reflecting half-mirror. The second camera is aligned with the second end of the microscope objective lens via a first reflecting mirror and the first half-reflecting half-mirror. The infrared light source is used to provide infrared light that penetrates the first sample and / or the second sample to the first end of the microscope objective lens. The controller is configured to: at a first moment, focus the microscope objective lens on the first sample so that one of the first camera and the second camera can capture a first image of the first sample; at a second moment, focus the microscope objective lens on the second sample so that the other of the first camera and the second camera can capture a second image of the second sample; and determine the lateral deviation of the first sample and / or the second sample based on the planar positions of the first image and the second image.

[0008] Furthermore, in some embodiments of the present invention, a first tube lens and a second tube lens are further included. The first tube lens is disposed between the first camera and the first half-reflecting half-mirror. The controller adjusts the distance between the first tube lens and the first camera to focus the microscope objective lens on the first surface of the first sample facing the second sample; and / or a second tube lens is disposed between the second camera and the first reflecting mirror. The controller adjusts the distance between the second tube lens and the second camera to focus the microscope objective lens on the second surface of the second sample facing the first sample.

[0009] Furthermore, in some embodiments of the present invention, the microscope objective lens is disposed above the first sample and the second sample, and the infrared light source is disposed below the first sample and the second sample, and provides infrared light to the first end of the microscope objective lens through backlighting to penetrate the first sample and the second sample.

[0010] Furthermore, in some embodiments of the present invention, the infrared light source is disposed on the sides of the first sample and the second sample, and is projected onto the first surface of the first sample above via a second reflector to provide infrared light that penetrates the first sample to the first end of the microscope objective lens.

[0011] Furthermore, in some embodiments of the present invention, the second reflector is a second semi-reflective half-mirror lens, which is located between the first semi-reflective half-mirror lens and the microscope objective lens to vertically project the infrared light incident from the side of the infrared light source onto the first surface of the first sample.

[0012] Furthermore, some embodiments of the present invention further include a lateral displacement mechanism connected to the first sample and / or the second sample, and configured to laterally adjust the position of the first sample and / or the second sample according to the lateral deviation to align the first sample with the second sample.

[0013] Furthermore, some embodiments of the present invention further include a longitudinal displacement mechanism for longitudinally adjusting the position of the first sample and / or the second sample after aligning the first sample and the second sample, so as to bond the first surface of the first sample to the second surface of the second sample.

[0014] Furthermore, in some embodiments of the present invention, the controller is also configured to: at a third moment after the bonding is completed, focus the microscope objective lens to the first sample, so that one of the first camera and the second camera can collect a third image of the first sample; at a fourth moment after the bonding is completed, focus the microscope objective lens to the second sample, so that the other of the first camera and the second camera can collect a fourth image of the second sample; and determine the alignment accuracy of the first sample and the second sample based on the planar positions of the third image and the fourth image.

[0015] Furthermore, in some embodiments of the present invention, the controller is further configured to: analyze the third image and / or the fourth image to determine whether there are bubbles on the bonding surface of the first sample and the second sample.

[0016] Furthermore, in some embodiments of the present invention, the first sample and the second sample are selected from wafers or integrated circuit chips.

[0017] In addition, the above-mentioned optical alignment method provided according to the second aspect of the present invention includes the following steps: at a first moment, focusing the microscope objective lens on a first sample at its first end so that a first camera at its second end can capture a first image of the first sample; at a second moment, focusing the microscope objective lens on a second sample at its first end so that a second camera can provide infrared light penetrating the first sample and / or the second sample to the first end of the microscope objective lens via an infrared light source to capture a second image of the second sample; and determining the lateral deviation of the first sample and / or the second sample based on the planar positions of the first image and the second image.

[0018] Furthermore, the computer-readable storage medium provided in accordance with the second aspect of the present invention stores computer instructions, which, when executed by a processor, implement the optical alignment method provided in accordance with the second aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above features and advantages of the present invention will be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or characteristics may have the same or similar reference numerals.

[0020] FIG1 is a schematic diagram showing the principles of an optical alignment device according to some embodiments of the present invention.

[0021] FIG2 shows a schematic structural diagram of an optical alignment device according to some embodiments of the present invention.

[0022] FIG3 is a schematic diagram showing the principles of an optical alignment device according to some embodiments of the present invention.

[0023] FIG4 shows a schematic flow chart of an optical alignment method according to some embodiments of the present invention.

[0024] FIG5 shows a schematic flow chart of a detection method according to some embodiments of the present invention.

[0025] Reference numerals: 10 infrared light source 11 microscope objective 12 first camera 13 second camera 14 first sample 15 second sample 16 first semi-reflecting half-mirror 17 first reflecting mirror 18 first tube lens 19 second tube lens 21 second semi-reflecting half-mirror DETAILED DESCRIPTION

[0026] The following specific embodiments illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. 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, the following description will include many specific details. 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.

[0027] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0028] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood to refer to the orientations depicted in that section and the accompanying drawings. These relative terms are used solely for convenience of description and do not necessarily imply that the devices described herein must be manufactured or operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0029] It will be understood that although the terms "first," "second," "third," etc. may be used herein to describe various components, regions, layers, and / or portions, these components, regions, layers, and / or portions should not be limited by these terms, and these terms are merely used to distinguish different components, regions, layers, and / or portions. Thus, a first component, region, layer, and / or portion discussed below may be referred to as a second component, region, layer, and / or portion without departing from some embodiments of the present invention.

[0030] As mentioned above, a common alignment method involves positioning the wafer and chip separately using two optical microscopes. However, the positioned chip still requires significant horizontal movement to complete the bonding process. Consequently, this mechanical movement increases alignment errors and affects bonding accuracy. Furthermore, existing semiconductor processing equipment requires additional inspection modules to monitor bonding accuracy and the presence of air bubbles.

[0031] In order to overcome the above-mentioned defects of the prior art, the present invention provides an optical alignment device, an optical alignment method and a computer-readable storage medium, which can align the wafer and chip by sharing a microscope objective lens, thereby avoiding large horizontal movement of the chip after positioning, and can directly detect the alignment accuracy of the wafer and chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and chip.

[0032] In some non-limiting embodiments, the optical alignment method provided in the second aspect of the present invention can be implemented based on the optical alignment device provided in the first aspect of the present invention. Specifically, the optical alignment device can be configured with a memory and a controller. The memory includes but is not limited to the computer-readable storage medium provided in the third aspect of the present invention, on which computer instructions are stored. The controller is connected to the memory and is configured to execute the computer instructions stored on the memory to implement the optical alignment method provided in the second aspect of the present invention.

[0033] Please refer to Figures 1 and 2 for details. Figure 1 shows a schematic diagram of the principle of an optical alignment device provided according to some embodiments of the present invention, and Figure 2 shows a schematic diagram of the structure of an optical alignment device provided according to some embodiments of the present invention.

[0034] In the embodiments shown in Figures 1 and 2, the optical alignment device provided by the first aspect of the present invention includes a microscope objective lens 11, a first camera 12, a second camera 13, an infrared light source 10, and a controller. The first end of the microscope objective lens 11 is directed toward a first sample 14 and a second sample 15 to be aligned. The first camera 12 is aligned with the second end of the microscope objective lens 11 via a first semi-reflecting mirror 16. The second camera 13 is aligned with the second end of the microscope objective lens 11 via a first reflector 17 and the first semi-reflecting mirror 16. The infrared light source 10 is configured to provide infrared light to the first end of the microscope objective lens 11 that penetrates the first sample 14 and / or the second sample 15. Here, the first sample 14 and the second sample 15 are selected from wafers or integrated circuit chips.

[0035] In addition, the optical alignment device provided by the first aspect of the present invention further includes a first tube lens 18 and a second tube lens 19. The first tube lens 18 is disposed between the first camera 12 and the first semi-reflecting mirror 16. Here, the controller can adjust the distance between the first tube lens 18 and the first camera 12 to focus the microscope objective 11 on the first surface of the first sample 14 facing the second sample 15. Similarly, the second tube lens 19 is disposed between the second camera 13 and the first reflecting mirror 17. Here, the controller can adjust the distance between the second tube lens 19 and the second camera 13 to focus the microscope objective 11 on the second surface of the first sample 14 facing the second sample 15.

[0036] Furthermore, in some embodiments, the microscope objective lens 11 is disposed above the first sample 14 and the second sample 15. The infrared light source 10 is optionally disposed below the first sample 14 and the second sample 15, and provides infrared light to the first end of the microscope objective lens 11 through backlighting to penetrate the first sample 14 and the second sample 15.

[0037] Please refer to FIG3 , which shows a schematic diagram of the principles of an optical alignment device provided according to some embodiments of the present invention.

[0038] In the embodiment shown in FIG3 , the infrared light source 10 is optionally positioned to the side of the first sample 14 and the second sample 15, projecting infrared light onto the first surface of the first sample 14 above via a second reflector, thereby providing infrared light that penetrates the first sample 14 to the first end of the microscope objective 11. Here, the second reflector can be a second semi-reflecting mirror 21. The second semi-reflecting mirror 21 is positioned between the first semi-reflecting mirror 16 and the microscope objective 11, projecting infrared light incident from the side of the infrared light source 10 perpendicularly onto the first surface of the first sample 14.

[0039] In addition, the optical alignment device provided by the first aspect of the present invention further includes a lateral displacement mechanism. The lateral displacement mechanism is connected to the first sample 14 and / or the second sample 15 and is configured to laterally adjust the position of the first sample 14 and / or the second sample 15 according to the lateral deviation to align the first sample 14 and the second sample 15.

[0040] In addition, the optical alignment device provided in the first aspect of the present invention further includes a longitudinal displacement mechanism for longitudinally adjusting the position of the first sample 14 and / or the second sample 15 after alignment of the first sample 14 and the second sample 15, so as to bond the first surface of the first sample 14 to the second surface of the second sample 15.

[0041] The following describes the operating principles of the optical alignment device described above, using examples of several optical alignment methods. Those skilled in the art will appreciate that these alignment method examples are merely non-limiting implementations of the present invention, intended to clearly illustrate the main concepts of the present invention and provide specific solutions that facilitate implementation by the public, rather than limiting the full functionality or operating methods of the optical alignment device. Similarly, the optical alignment device is merely a non-limiting implementation of the present invention and does not limit the execution entities or execution order of the steps in these optical alignment methods.

[0042] Please refer to FIG. 4 for details, which shows a schematic flow chart of an optical alignment method according to some embodiments of the present invention.

[0043] As shown in FIG4 , at a first moment, the controller can first adjust the distance between the first tube lens 18 and the first camera 12 to focus the microscope objective lens 11 on the first sample 14, allowing one of the first camera 12 and the second camera 13 to capture a first image of the first sample 14. Then, at a second moment, the controller can adjust the distance between the second tube lens 19 and the second camera 13 to focus the microscope objective lens 11 on the second sample 15, allowing the other of the first camera 12 and the second camera 13 to capture a second image of the second sample 15. The controller can then determine the lateral deviation of the first sample 14 and / or the second sample 15 based on the planar positions of the first and second images.

[0044] Afterwards, the controller of the optical alignment device may control the lateral displacement mechanism to laterally adjust the position of the first sample 14 and / or the second sample 15 according to the lateral deviation, so as to align the first sample 14 and the second sample 15 .

[0045] Thereafter, the controller of the optical alignment device may continue to control the longitudinal displacement mechanism to longitudinally adjust the positions of the first sample 14 and / or the second sample 15 to bond the first surface of the first sample 14 to the second surface of the second sample 15 .

[0046] Please refer to FIG5 , which shows a flow chart of a detection method according to some embodiments of the present invention.

[0047] As shown in FIG5 , the optical alignment device provided by the first aspect of the present invention can also detect the alignment accuracy of the first sample 14 and the second sample 15. At a third moment after bonding is completed, the controller can again adjust the distance between the first tube lens 18 and the first camera 12 to focus the microscope objective lens 11 on the first sample 14, allowing one of the first camera 14 and the second camera 14 to capture a third image of the first sample 14. Then, at a fourth moment after bonding is completed, the controller can adjust the distance between the second tube lens 19 and the second camera 13 to focus the microscope objective lens 11 on the second sample 15, allowing the other of the first camera 12 and the second camera 13 to capture a fourth image of the second sample 15. Finally, the controller can determine the alignment accuracy of the first sample 14 and the second sample 15 based on the planar positions of the third and fourth images.

[0048] Furthermore, the controller of the optical alignment device may also analyze the third image and / or the fourth image to determine whether there are bubbles on the bonding surfaces of the first sample 14 and the second sample 15 .

[0049] In summary, the above-mentioned optical alignment device, optical alignment method and computer-readable storage medium provided by the present invention can align the wafer and chip by sharing a microscope objective lens, thereby avoiding large horizontal movement of the chip after positioning, and can directly detect the alignment accuracy of the wafer and chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and chip.

[0050] Although the above methods are illustrated and described as a series of acts for simplicity of explanation, it is to be understood and appreciated that these methods are not limited by the order of the acts, as some acts may occur in a different order and / or concurrently with other acts from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art according to one or more embodiments.

[0051] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An optical alignment device, characterized in that: include: A microscope objective lens, a first end of which faces the first sample and the second sample to be aligned; A first camera, aligned with the second end of the microscope objective lens via a first semi-reflective semi-mirror lens; A second camera is aligned with the second end of the microscope objective lens via the first reflecting mirror and the first semi-reflecting semi-mirror lens; an infrared light source, used for providing infrared light penetrating the first sample and / or the second sample to the first end of the microscope objective lens; as well as A controller is configured to: at a first moment, focus the microscope objective lens on the first sample so that one of the first camera and the second camera can capture a first image of the first sample; At a second moment, focusing the microscope objective lens onto the second sample so that the other of the first camera and the second camera can acquire a second image of the second sample; And according to the plane positions of the first image and the second image, the lateral deviation of the first sample and / or the second sample is determined.

2. The optical alignment device according to claim 1, characterized in that: Also includes: a first tube lens disposed between the first camera and the first semi-reflective and semi-transmissive mirror, wherein the controller adjusts the distance between the first tube lens and the first camera to make the microscope objective lens focus on a first surface of the first sample facing the second sample; and / or The second tube lens is disposed between the second camera and the first reflector, wherein the controller adjusts the distance between the second tube lens and the second camera to make the microscope objective lens focus on the second surface of the second sample facing the first sample.

3. The optical alignment device according to claim 1, characterized in that: The microscope objective lens is disposed above the first sample and the second sample. The infrared light source is disposed below the first sample and the second sample, and provides infrared light penetrating the first sample and the second sample to the first end of the microscope objective lens in a back-illumination manner.

4. The optical alignment device according to claim 1, characterized in that: The infrared light source is disposed on the side of the first sample and the second sample, and is projected onto the first surface of the first sample above via the second reflector, so as to provide infrared light penetrating the first sample to the first end of the microscope objective lens.

5. The optical alignment device according to claim 4, characterized in that: The second reflector is a second semi-reflective and semi-mirror, wherein the second semi-reflective and semi-mirror is located between the first semi-reflective and semi-mirror and the microscope objective lens to vertically project the infrared light incident from the side of the infrared light source onto the first surface of the first sample.

6. The optical alignment device according to claim 1, wherein: Also includes: A lateral displacement mechanism is connected to the first sample and / or the second sample and is used to laterally adjust the position of the first sample and / or the second sample according to the lateral deviation to align the first sample and the second sample.

7. The optical alignment device according to claim 6, characterized in that: Also includes: The longitudinal displacement mechanism is used to longitudinally adjust the position of the first sample and / or the second sample after aligning the first sample and the second sample, so as to bond the first surface of the first sample to the second surface of the second sample.

8. The optical alignment device according to claim 7, characterized in that: The controller is also configured to: At a third moment after the bonding is completed, focusing the microscope objective lens onto the first sample so that the one of the first camera and the second camera can acquire a third image of the first sample; At a fourth moment after the bonding is completed, focusing the microscope objective lens onto the second sample so that the other of the first camera and the second camera can acquire a fourth image of the second sample; as well as The alignment accuracy between the first sample and the second sample is determined according to the plane positions of the third image and the fourth image.

9. The optical alignment device according to claim 8, characterized in that: The controller is also configured to: The third image and / or the fourth image are analyzed to determine whether there are bubbles on the bonding surface of the first sample and the second sample.

10. The optical alignment device according to claim 1, wherein: The first sample and the second sample are selected from wafers or integrated circuit chips.

11. An optical alignment method, characterized in that: The following steps are involved: At a first moment, focusing the microscope objective lens onto a first sample at a first end thereof, so that a first camera at a second end thereof can capture a first image of the first sample; At a second moment, the microscope objective lens is focused on a second sample at a first end thereof, so that a second camera provides infrared light penetrating the first sample and / or the second sample to the first end of the microscope objective lens via an infrared light source, and collects a second image of the second sample; as well as The lateral deviation of the first sample and / or the second sample is determined according to the plane positions of the first image and the second image.

12. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the optical alignment method according to claim 11 is implemented.

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