Optical alignment apparatus, optical alignment method, and storage medium

Abstract

The 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. The first end of the microscope objective faces a first sample and a second sample to be aligned. And the first camera is aligned with the second end of the microscope objective through the first semi-reflecting and semi-transmitting mirror. And the second camera is aligned with the second end of the microscope objective through the first reflecting mirror and the first semi-reflecting and semi-transmitting mirror. The infrared light source is used for providing infrared light penetrating through the first sample and / or the second sample to the first end of the microscope objective. According to the invention, the wafer and the chip are aligned by sharing one microscope objective, so that the chip can be prevented from greatly moving horizontally after being positioned, and the alignment precision of the wafer and the chip and whether bubbles exist on the bonding surface can be directly detected, so that the bonding quality of the wafer and the chip is improved.

Description

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] In the process of semiconductor device processing, the bonding process between wafer and chip is very critical. Before bonding, semiconductor processing equipment needs to align the wafer and chip. A common alignment method is to use two optical microscope systems to position the wafer and chip respectively. However, the positioned chip still needs to be moved horizontally to complete the bonding. Therefore, the mechanical movement of this method increases the alignment error and affects the bonding accuracy. In addition, existing semiconductor processing equipment needs to set up additional detection modules to detect the bonding accuracy and whether bubbles are generated 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 can 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. Summary of the invention

[0004] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or decisive elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0005] 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 the 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 the chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and the chip.

[0006] 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 collect 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 collect a second image of the second sample; and determine the lateral deviation of the first sample and / or the second sample according to the plane positions of the first image and the second image.

[0007] 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 so that the microscope objective lens focuses 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 so that the microscope objective lens focuses on the second surface of the second sample facing the first sample.

[0008] Furthermore, in some embodiments of the present invention, 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 by backlighting.

[0009] 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.

[0010] Furthermore, in some embodiments of the present invention, the second reflector is a second semi-reflective mirror located between the first semi-reflective 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.

[0011] Furthermore, in some embodiments of the present invention, a lateral displacement mechanism is further included. The lateral displacement mechanism is connected to the first sample and / or the second sample and is used to adjust the position of the first sample and / or the second sample laterally according to the lateral deviation to align the first sample and the second sample.

[0012] Furthermore, in some embodiments of the present invention, a longitudinal displacement mechanism is further included, wherein 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.

[0013] 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.

[0014] 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.

[0015] Furthermore, in some embodiments of the present invention, the first sample and the second sample are selected from wafers or integrated circuit chips.

[0016] 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 to a first sample at its first end so that a first camera at its second end can collect a first image of the first sample; at a second moment, focusing the microscope objective lens to 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 collect 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.

[0017] In addition, the computer-readable storage medium provided according to the second aspect of the present invention stores computer instructions, which, when executed by a processor, implement the optical alignment method provided by the second aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above features and advantages of the present invention can 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 features may have the same or similar reference numerals.

[0019] Figure 1 A schematic diagram showing the principles of an optical alignment device provided according to some embodiments of the present invention is shown.

[0020] Figure 2 A schematic structural diagram of an optical alignment device provided according to some embodiments of the present invention is shown.

[0021] Figure 3 A schematic diagram showing the principles of an optical alignment device provided according to some embodiments of the present invention is shown.

[0022] Figure 4 A schematic flow chart of an optical alignment method provided according to some embodiments of the present invention is shown.

[0023] Figure 5 A schematic flow chart of a detection method provided according to some embodiments of the present invention is shown.

[0024] Reference numerals:

[0025] 10 Infrared light source

[0026] 11 Microscope objective

[0027] 12 First Camera

[0028] 13. Second Camera

[0029] 14 First Sample

[0030] 15 Second Sample

[0031] 16 The first half-reflecting half-mirror

[0032] 17 First Reflector

[0033] 18 First tube mirror

[0034] 19 Second tube mirror

[0035] 21 The second half-reflecting half-mirror DETAILED DESCRIPTION

[0036] The following specific embodiments illustrate the implementation of the present invention, and 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 implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation 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.

[0037] 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.

[0038] 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.

[0039] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0040] As mentioned above, a common alignment method is to position the wafer and chip respectively through two optical microscope systems. However, the positioned chip still needs to be moved horizontally to complete the bonding. Therefore, the mechanical movement of this method increases the alignment error and affects the bonding accuracy. In addition, existing semiconductor processing equipment needs to be equipped with additional detection modules to detect the bonding accuracy and whether bubbles are generated.

[0041] 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 the 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 the chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and the chip.

[0042] 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.

[0043] Please refer to Figure 1 and Figure 2 , Figure 1 FIG. 1 is a schematic diagram showing a principle of an optical alignment device provided according to some embodiments of the present invention. Figure 2 A schematic structural diagram of an optical alignment device provided according to some embodiments of the present invention is shown.

[0044] exist Figure 1 and Figure 2 In the illustrated embodiment, the optical alignment device provided by the first aspect of the present invention comprises 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 faces the first sample 14 and the second sample 15 to be aligned. The first camera 12 is aligned with the second end of the microscope objective lens 11 via the first semi-reflecting half-mirror 16. The second camera 13 is aligned with the second end of the microscope objective lens 11 via the first reflecting mirror 17 and the first semi-reflecting half-mirror 16. The infrared light source 10 is used to provide infrared light that penetrates the first sample 14 and / or the second sample 15 to the first end of the microscope objective lens 11. Here, the first sample 14 and the second sample 15 are selected from wafers or integrated circuit chips.

[0045] 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-reflective mirror 16. Here, the controller can focus the microscope objective lens 11 on the first surface of the first sample 14 facing the second sample 15 by adjusting the distance between the first tube lens 18 and the first camera 12. Similarly, the second tube lens 19 is disposed between the second camera 13 and the first reflective mirror 17. Here, the controller can focus the microscope objective lens 11 on the second surface of the second sample 15 facing the first sample 14 by adjusting the distance between the second tube lens 19 and the second camera 13.

[0046] Further, 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 penetrating the first sample 14 and the second sample 15 to the first end of the microscope objective lens 11 by backlighting.

[0047] Please refer to Figure 3 , Figure 3 A schematic diagram showing the principles of an optical alignment device provided according to some embodiments of the present invention is shown.

[0048] exist Figure 3 In the illustrated embodiment, the infrared light source 10 is optionally disposed on the side of the first sample 14 and the second sample 15, and is projected onto the first surface of the first sample 14 above via the second reflector, so as to provide infrared light penetrating the first sample 14 to the first end of the microscope objective lens 11. Here, the second reflector can be a second semi-reflective mirror 21. The second semi-reflective mirror 21 is located between the first semi-reflective mirror 16 and the microscope objective lens 11, so as to vertically project the infrared light incident from the side of the infrared light source 10 onto the first surface of the first sample 14.

[0049] In addition, the optical alignment device provided in 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 used to adjust the position of the first sample 14 and / or the second sample 15 laterally according to the lateral deviation amount, so as to align the first sample 14 and the second sample 15.

[0050] In addition, the optical alignment device provided in the first aspect of the present invention further includes a longitudinal displacement mechanism. The longitudinal displacement mechanism is used to longitudinally adjust the position of the first sample 14 and / or the second sample 15 after aligning 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.

[0051] The working principle of the above optical alignment device will be described below in conjunction with some embodiments of the optical alignment method. Those skilled in the art will understand that the embodiments of these alignment methods are only some non-limiting implementation methods provided by the present invention, which are intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than limiting all functions or all working modes of the optical alignment device. Similarly, the optical alignment device is also only a non-limiting implementation method provided by the present invention, and does not constitute a limitation on the execution subject and execution order of each step in these optical alignment methods.

[0052] Please refer to Figure 4 , Figure 4 A schematic flow chart of an optical alignment method provided according to some embodiments of the present invention is shown.

[0053] like Figure 4 As shown, 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, so that one of the first camera 12 and the second camera 13 can collect 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, so that the other of the first camera 12 and the second camera 13 can collect a second image of the second sample 15. Then, the controller can determine the lateral deviation of the first sample 14 and / or the second sample 15 according to the plane positions of the first image and the second image.

[0054] 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 .

[0055] Thereafter, the controller of the optical alignment device may continue to control the longitudinal displacement mechanism to longitudinally adjust the position 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 .

[0056] Please refer to Figure 5 , Figure 5 A schematic flow chart of a detection method provided according to some embodiments of the present invention is shown.

[0057] like Figure 5As shown, 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 the third moment after the bonding is completed, the controller can focus the microscope objective lens 11 on the first sample 14 by adjusting the distance between the first barrel lens 18 and the first camera 12 again, so that one of the first camera 14 and the second camera 14 can collect the third image of the first sample 14. Then, at the fourth moment after the bonding is completed, the controller can focus the microscope objective lens 11 on the second sample 15 by adjusting the distance between the second barrel lens 19 and the second camera 13, so that the other of the first camera 12 and the second camera 13 can collect the 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 according to the plane positions of the third image and the fourth image.

[0058] 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 .

[0059] 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 the 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 the chip and whether there are bubbles on the bonding surface, so as to improve the bonding quality of the wafer and the chip.

[0060] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0061] 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 should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An optical alignment device, It is 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, It is 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, It is 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, It is 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, It is 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, It is characterized in that 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, It is 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, It is 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, It is 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, It is characterized in that The first sample and the second sample are selected from wafers or integrated circuit chips.

11. An optical alignment method, It is 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, It is 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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