Bonding force detection device and method

Abstract

A bonding force detection device and method, the bonding force detection device including: a light emitting device that irradiates light to bonding surfaces of wafers or substrates bonded to each other; an image sensing device that senses an optical image of the bonding surface with respect to the light generated in the light emitting device; and a control unit that determines a joining state of the joining surface on the basis of the optical image received from the image sensing device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0159182 filed in the Korean Intellectual Property Office on November 16, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a bonding force detection device and method, and more particularly, to a bonding force detection device and method capable of accurately detecting the bonding force of a bonding surface of a wafer or a substrate in a non-destructive manner by using an optical image utilizing infrared rays or short-wave infrared rays. Background Art

[0004] When bonding wafers to wafers, or bonding dies to wafers, there may be voids, bubbles, or foreign matter on the bonding surfaces between the bonded wafers or substrates, causing a significant decrease in the strength of the bonding surfaces.

[0005] In the past, in order to confirm the phenomenon of reduced strength of the bonding surface, destructive wafer bonding force detection devices were widely used. This device must physically destroy a part of the wafer, such as forcibly inserting a blade into the bonding surface located at the edge of the wafer to be bonded, and measuring the resistance value while destroying the bonding surface. Summary of the invention

[0006] Technical issues to be solved

[0007] However, these conventional wafer bonding force detection devices can only measure the bonding force at the edge of the wafer, and cannot measure the overall bonding force distribution of the wafer bonding surface. In addition, a separate detection device that mechanically destroys the wafer is relatively expensive, which not only increases the detection cost, but also causes the wafer to be destroyed after the detection, thus resulting in a waste of wafers. In addition, the detection takes a lot of time, which will cause a significant decrease in the detection work efficiency.

[0008] In order to solve various problems including the above problems, the object of the present invention is to provide a bonding force detection device and method, which can accurately detect the bonding force of the bonding surface of a wafer or substrate in a non-destructive manner using an optical image using infrared or short-wave infrared rays. However, such problems are exemplary and do not limit the scope of the present invention.

[0009] Solutions to technical problems

[0010] To solve the problem, according to the solution of the present invention, the joining force detection device may include: a light-emitting device, which irradiates light to the joining surfaces of wafers or substrates that are joined to each other; an image sensing device, which senses the optical image of the light generated in the light-emitting device on the joining surface; and a control unit, which determines the joining state of the joining surface based on the optical image received from the image sensing device.

[0011] Furthermore, according to the present invention, the light comprises infrared light or short-wave infrared light.

[0012] Furthermore, according to the present invention, the optical image is a two-dimensional plane image, which includes the entire area of ​​the bonding surface and is displayed as a brightness difference of the image according to the difference in partial bonding force of the bonding surface or the presence or absence of bubbles or foreign matter.

[0013] Furthermore, according to the present invention, the optical image is a three-dimensional shape image that includes the entire area of ​​the bonding surface and is displayed in three dimensions according to differences in partial surface shapes of the bonding surface or shapes of bubbles or foreign matter.

[0014] Furthermore, according to the present invention, the control unit determines whether the joining force is poor based on the standard brightness of the image and a pre-matched joining force database based on different brightnesses.

[0015] Furthermore, according to the present invention, the control unit includes an artificial intelligence model that learns an image for learning in a deep learning manner, and judges the optical image to thereby judge whether the bonding force is poor.

[0016] Furthermore, according to the present invention, the image sensing device is a transmission-type sensing device that senses light transmitted through the bonding surface, or a reflection-type sensing device that senses light reflected by the bonding surface.

[0017] Furthermore, according to the present invention, the image sensing device is an overall image sensing device, which is disposed above or below the joint surface and is capable of capturing an overall image of the joint surface.

[0018] Furthermore, according to the present invention, the image sensing device is a partial image sensing device, and the partial image sensing device takes a partial image of the joining surface by means of a scanning transport device that moves along the joining surface or is capable of moving the joining surface.

[0019] In addition, according to the present invention, the control unit receives a brightness signal from a brightness sensor arranged around the wafer or substrate, or receives a brightness signal from the optical image; in order to improve the recognition ability of the optical image, a brightness control signal for adjusting the light brightness is transmitted to the light-emitting device.

[0020] In addition, according to the present invention, the control unit receives a frequency signal from a frequency sensor arranged around the wafer or substrate, or receives a frequency signal from the optical image; in order to improve the recognition ability of the optical image, a frequency control signal that changes the light frequency is transmitted to the light-emitting device.

[0021] In addition, according to the present invention, the control unit receives a thickness signal from a thickness measuring sensor arranged around the wafer or substrate, or receives a thickness signal from the optical image; in order to improve the recognition ability of the optical image, a thickness corresponding control signal that changes the brightness of the light or the frequency of the light is transmitted to the light-emitting device.

[0022] Furthermore, according to the present invention, the image sensing device is disposed vertically above or vertically below the bonding surface.

[0023] Furthermore, according to the present invention, the image sensing device includes a first camera, which is obliquely disposed at a first angle in a first direction with reference to a position vertically above or vertically below the joint surface.

[0024] Furthermore, according to the present invention, the image sensing device includes a second camera that is obliquely disposed at a second angle different from the first angle in the first direction with reference to vertically above or vertically below the joint surface.

[0025] Furthermore, according to the present invention, the image sensing device includes a third camera, and the third camera is obliquely arranged at a third angle in a second direction different from the first direction with reference to vertically above or vertically below the joint surface.

[0026] In addition, according to the present invention, the image sensing device includes a movable camera, and the illumination angle of the movable camera is changed by an angle moving device that moves from a fourth angle in the first direction to a fifth angle based on vertically above or vertically below the joint surface.

[0027] Furthermore, according to the present invention, the bonding force detection device further includes a rotating device, which rotates the wafers or substrates bonded to each other so as to be able to sense the optical image at different angles.

[0028] On the other hand, in order to solve the problem, the bonding force detection method according to the solution of the present invention includes: (a) a step of irradiating light onto the bonding surfaces of wafers or substrates that are bonded to each other; (b) a step of sensing the optical image of the light on the bonding surfaces; and (c) a step of judging the bonding state of the bonding surfaces based on the optical image by utilizing a past database or a learned artificial intelligence model.

[0029] On the other hand, in order to solve the above-mentioned problem, a bonding force detection device according to the solution of the present invention comprises: a light emitting device for irradiating light onto bonding surfaces of mutually bonded wafers or substrates; an image sensing device for sensing an optical image of the light generated in the light emitting device on the bonding surfaces; and a control unit for judging the bonding state of the bonding surfaces based on the optical image received from the image sensing device, wherein the light comprises infrared light or short-wave infrared light, and the optical image is a two-dimensional plane image, and the two-dimensional plane image comprises the entire area of ​​the bonding surface and is based on the partial area of ​​the bonding surface. The difference in bonding force or the presence or absence of bubbles or foreign matter is displayed as a brightness difference in the image; or the optical image is a three-dimensional shape image, which includes the entire area of ​​the bonding surface and is displayed in three dimensions according to the difference in partial surface shape of the bonding surface or the shape of bubbles or foreign matter, and the control unit judges the optical image based on the standard brightness of the image and a pre-matched bonding force database based on different brightnesses to determine whether the bonding force is poor; or the control unit includes an artificial intelligence model, which learns the image used for learning in a deep learning manner, and judges the optical image to determine whether the bonding force is poor.

[0030] Effects of the Invention

[0031] According to the multiple embodiments of the present invention as described above, the bonding force of the bonding surface between wafers or substrates can be accurately checked in a non-destructive manner using optical images using infrared or short-wave infrared, and the overall bonding force distribution, the presence or absence of pores, bubbles or foreign matter, and the position of the bonding surface between wafers or substrates can be accurately measured, and optical devices such as light-emitting devices or image detection devices are relatively easy to develop and inexpensive, so the inspection cost can be greatly reduced. Since the wafer or substrate can continue to be used after being detected in a non-destructive manner, it is very economical, and the image detection time and analysis time are short, so it has the effect of greatly improving the detection efficiency and productivity. Of course, these effects do not limit the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 FIG. 1 is a side view conceptually showing a joining force detection device according to some embodiments of the present invention.

[0033] Figure 2 FIG. 1 is a side view conceptually showing a joining force detection device according to some other embodiments of the present invention.

[0034] Figure 3 FIG. 1 is a side view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0035] Figure 4 FIG. 1 is a side view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0036] Figure 5 FIG. 1 is a side view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0037] Figure 6 FIG. 1 is a perspective view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0038] Figure 7 FIG. 1 is a side view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0039] Figure 8 FIG. 1 is a perspective view conceptually showing a joining force detection device according to another embodiment of the present invention.

[0040] Fig. 9 is a flow chart showing a method for detecting a joining force according to some embodiments of the present invention.

[0041] Fig.10 and Fig.11 1 is a photograph showing an example of an optical image of a joining force detection device according to some embodiments of the present invention. DETAILED DESCRIPTION

[0042] Hereinafter, with reference to the accompanying drawings, several preferred embodiments of the present invention are described in detail.

[0043] The embodiments of the present invention are provided to more completely explain the present invention to those with conventional knowledge in the technical field. The following embodiments may be transformed into a variety of different forms, and the scope of the present invention is not limited to the following embodiments. On the contrary, these embodiments are provided to make the present disclosure more substantial and complete, and to fully convey the technical concept of the present invention to those skilled in the art. In addition, for ease of description and clarity, the thickness or size of each layer in the drawings is exaggerated.

[0044] The terms used in this specification are intended to be used to describe specific embodiments and are not intended to limit the present invention. As used in this specification, unless the context clearly indicates otherwise, the singular form may include the plural form. In addition, when used in this specification, "comprise" and / or "comprising" refer to the existence of the shapes, numbers, steps, operations, parts, elements and / or these groups, and do not exclude the existence or addition of one or more other shapes, numbers, operations, parts, elements and / or these groups.

[0045] Embodiments of the present invention will be described below with reference to the accompanying drawings which briefly illustrate ideal embodiments of the present invention. In the accompanying drawings, variations in the shapes shown are expected, for example, depending on manufacturing techniques and / or tolerances. Therefore, embodiments of the present inventive concept should not be construed as limited to the specific shapes of the regions shown in this specification, but should include variations in shapes caused, for example, by manufacturing.

[0046] Figure 1 1 is a side view conceptually showing a joining force detection device (100) according to some embodiments of the present invention.

[0047] First, if Figure 1 As shown, a bonding force detection device (100) according to some embodiments of the present invention can generally include a light emitting device (10), an image sensing device (20) and a control unit (30).

[0048] The light emitting device (10) may be a lighting device that irradiates light onto a bonding surface (F) of various substrates such as mutually bonded wafers (W1) (W2), a multilayer circuit board or a display panel.

[0049] For the light emitting device (10), if Figure 1 As shown, for example, various lighting devices such as various light-emitting elements that generate light (including infrared light or short-wave infrared light), infrared light-emitting elements, infrared LEDs (Light Emitted Diodes) or infrared lamps can be used.

[0050] This infrared lighting device can detect features that cannot be identified by visible light, so the infrared light used in infrared lighting can use near infrared light (NIR, Near Infrared Ray) and short wave infrared light (SWIR, Short Wavelength Infrared Ray).

[0051] Infrared is light with a wavelength of approximately 700nm to 1mm, which is longer than the 760nm to 830nm light known as the upper limit of human vision and is almost imperceptible to humans.

[0052] The wavelength band used in the image processing of the present invention is a wavelength band called near infrared or short-wave infrared. The wavelength used can be different depending on the light receiving element of the image sensing device (20). The wavelength corresponding to the bonding surface of the wafer or substrate to be detected can be set, and the camera and lighting can be selected.

[0053] Near infrared rays are in the wavelength region of 750nm to 1000nm, and can penetrate the surface of a wafer or substrate which would otherwise hinder detection of the bonding surface of the wafer or substrate.

[0054] Short-wave infrared rays are in the wavelength region of 1000nm to 2500nm, and can penetrate not only the surface of a wafer or substrate but also the wafer or substrate depending on the wavelength band.

[0055] Short-wave infrared rays can be absorbed by water, so it is possible to determine whether there is water, pores, bubbles or other foreign matter. For example, the difference in transmittance of materials at different wavelengths can be used to determine pores, bubbles, foreign matter or water. For example, water can absorb 1450nm light and appear black in the optical image.

[0056] For the image sensing device (20), various image sensing devices such as image sensing elements, image sensing sensors, image sensing cameras, image spectrometers, etc. that are all capable of sensing the optical image of the light generated in the light-emitting device (10) on the joint surface (F) can be used.

[0057] The image sensing device (20) may use various optical components such as light receiving elements, lenses or bandpass filters of various shapes or materials to receive infrared light or short-wave infrared light.

[0058] For the control unit (30), various control devices such as various computing devices, signal processing devices, central processing units, microprocessors, semiconductor chips, integrated circuits, substrates, circuit boards, electronic components, storage devices storing programs, calculators, server calculators, personal computers, smart phones, smart tablets, smart devices, etc. can be used to judge the bonding state of the bonding surface (F) based on the optical image received from the image sensing device (20).

[0059] The optical image may be a two-dimensional plane image including a portion or the entire area of ​​the bonding surface (F) and displayed by the brightness difference of the image according to the difference in partial bonding force of the bonding surface (F) or the presence or absence of bubbles or foreign matter.

[0060] However, the optical image is not necessarily limited to this, and can be a three-dimensional shape image that includes a portion or the entire area of ​​the joining surface (F) and is displayed in three dimensions based on the difference in the partial surface shape of the joining surface (F) or the shape of bubbles or foreign matter.

[0061] The control unit (30) can judge the optical image based on the standard brightness of the image and a pre-matched database of bonding forces based on different brightnesses, thereby judging whether the bonding force is poor.

[0062] For this bonding force database based on different brightness, optical images are obtained based on different brightness of the bonding surface of a portion of the wafer or substrate, and then the obtained partial optical images are matched with the bonding force data measured by actual destructive methods.

[0063] In addition, the control unit (30) may include an artificial intelligence model, for example, the artificial intelligence model learns the image used for learning in a deep learning manner, judges the optical image and thus judges whether the bonding force is poor.

[0064] For example, in the control unit (30), the artificial intelligence model can be learned in a deep learning manner by using a database of bonding forces based on different brightnesses, thereby using an artificial intelligence model with an accuracy rate of more than 95% to judge the optical image and thus determine whether the bonding force is poor.

[0065] These artificial intelligence models can utilize various neural network algorithms that imitate the principles and structures of human neural networks, such as ANN (Artificial Neural Network), DNN (Deep Neural Network), CNN (Convolution Neural Network) and RNN (Recurrent Neural Network).

[0066] For example, the image sensing device (20) may be Figure 1 The transmissive sensing device (21) shown senses light passing through the joining surface (F).

[0067] In addition, for example, the image sensing device (20) may be Figure 1 The overall image sensing device (23) shown is arranged above the joint surface (F) and can capture the overall image of the joint surface (F).

[0068] The light emitting device (10) may be arranged vertically below the joint surface (F), and the image sensing device (20) may be arranged vertically above the joint surface (F). However, the invention is not limited thereto. For example, the light emitting device (10) may be arranged vertically above the joint surface (F), and the image sensing device (20) may be arranged vertically below the joint surface (F).

[0069] Therefore, by using the transmission sensing device (21) and the overall image sensing device (23), the light generated in the light emitting device (10) with uniform light quantity passes through the bonding surface (F) of the mutually bonded wafers (W1) (W2), and part of the light is absorbed by, for example, pores, bubbles or foreign matter, thereby generating a difference in brightness. The image sensing device (20) senses this difference in brightness through an optical image, so that the control unit (30) can judge the bonding state of the bonding surface (F) very accurately in a non-destructive manner based on the optical image, using a past database or a learned artificial intelligence model.

[0070] At the same time, if Figure 1 As shown, the control unit (30) receives a brightness signal from a brightness sensor (S1) arranged around a wafer (W1) (W2) or a substrate, or receives a brightness signal from an optical image; in order to improve the recognition ability of the optical image, a brightness control signal for adjusting the light brightness can be transmitted to the light emitting device (10).

[0071] Therefore, when the brightness signal value received by the control unit (30) from the brightness sensor (S1) is too low or too high, causing the optical image to become too dark or too bright, the recognition ability of the brightness of the optical image is significantly reduced, and the brightness of the light-emitting device (10) can be optimally adjusted based on the brightness signal of the brightness sensor (S1) or the brightness signal of the optical image.

[0072] Therefore, according to the present invention, an optical image in an optimal state can always be obtained for wafers or substrates of various materials and shapes, so that the bonding force can be determined very accurately.

[0073] In addition, if Figure 1 As shown, the control unit (30) receives a frequency signal from a frequency sensor (S2) disposed around a wafer (W1) (W2) or a substrate, or receives a frequency signal from an optical image. To improve the recognition of the optical image, a frequency control signal that changes the light frequency can be transmitted to the light emitting device (10).

[0074] Therefore, when the frequency signal value received by the control unit (30) from the frequency sensor (S2) is too low or too high, causing the transmittance to vary with the frequency, thereby reducing the recognition ability of the optical image, the frequency of the light of the light-emitting device (10) can be optimally adjusted based on the frequency signal emitted by the frequency sensor (S2) or the frequency signal of the optical image.

[0075] Therefore, according to the present invention, an optical image in an optimal state can always be obtained for wafers or substrates of various materials and shapes, so that the bonding force can be determined very accurately.

[0076] In addition, if Figure 1As shown, the control unit (30) receives a thickness signal from a thickness measurement sensor (S3) arranged around a wafer (W1) (W2) or a substrate, or receives a thickness signal from an optical image; in order to improve the recognition ability of the optical image, a thickness corresponding control signal that changes the brightness of light or the frequency of light can be transmitted to the light emitting device (10).

[0077] Therefore, when the thickness signal value received by the control unit (30) from the thickness measurement sensor (S3) is too thin or too thick, resulting in a decrease in the recognition ability of the optical image, the brightness or frequency of the light of the light emitting device (10) can be optimally adjusted based on the thickness signal of the thickness measurement sensor (S3) or the thickness signal of the optical image.

[0078] Therefore, according to the present invention, an optical image in an optimal state can always be obtained for wafers or substrates of various materials and shapes, so that the bonding force can be determined very accurately.

[0079] According to the present invention, infrared light or short-wave infrared light optical images can be used to accurately detect the bonding force of the bonding surface of the wafer or substrate in a non-destructive manner, and the overall bonding force distribution of the bonding surface (F) between the wafer (W1) (W2) or the substrate, the presence and position of pores, bubbles or foreign matter, etc. can be accurately measured. Optical devices such as light-emitting devices and image sensing devices (20) are relatively easy to develop and inexpensive, which can greatly reduce the detection cost, and the wafer or substrate detected in a non-destructive manner can be used as it is, so it is very economical, and the image detection time and analysis time are short, which can greatly improve the detection efficiency and work efficiency.

[0080] Figure 2 is a side view conceptually showing a joining force detection device (200) according to some other embodiments of the present invention.

[0081] like Figure 2 As shown, the image sensing device (20) of the joining force detection device (200) according to some other embodiments of the present invention may be a reflective sensing device (22) that senses light reflected by the joining surface (F).

[0082] Therefore, the light generated by the light emitting device (10) can be reflected by the bonding surface (F) and received by the image sensing device (20), and the control unit (30) can use these reflected optical images to determine the bonding force of the bonding surface (F).

[0083] For example, the image sensing device (20) can be disposed above the bonding surface (F), but is not limited thereto. As shown by the dotted line, it can also be disposed on the side of the bonding surface (F), or it can also be disposed at a different position.

[0084] Therefore, according to the present invention, the light emitting device (10) or the image sensing device (20) etc. can be freely arranged at different positions in a transmission type or a reflection type, and is not limited by the installation space.

[0085] Figure 3 It is a side view conceptually showing a joining force detection device (300) according to another embodiment of the present invention.

[0086] like Figure 3 As shown, the image sensing device (20) of the joining force detection device (300) according to some or other embodiments of the present invention may be a partial image sensing device (24), which captures a partial image of the joining surface (F) by means of a scanning transmission device (M1) that moves along the joining surface (F) or is capable of moving the joining surface (F).

[0087] Therefore, when the partial image sensing device (24) adopts this scanning method, although some scanning transmission time is required, the resolution and accuracy of the partial optical image that can be obtained can be greatly improved.

[0088] Figure 4 It is a side view conceptually showing a joining force detection device (400) according to another embodiment of the present invention.

[0089] like Figure 4 As shown, the image sensing device (20) of the joining force detection device (400) according to another part or other embodiments of the present invention may include a first camera (C1); the first camera (C1) is tilted at a first angle (A1) in a first direction (I) with reference to vertically above or vertically below the joining surface (F).

[0090] Therefore, the first angle (A1) as the setting angle of the first camera (C1) as described above can be fixedly set at an angle with optimal recognition ability, that is, it can be fixedly set at an angle with optimal recognition ability for various pores, bubbles or foreign objects that may exist on the bonding surface (F) according to wafers (W1) (W2) or substrates under different materials and environments.

[0091] Therefore, operators can set the optimal first angle (A1) according to different types and shapes of wafers or substrates, thereby significantly improving the recognition and resolution of optical images.

[0092] Figure 5 It is a side view conceptually showing a joining force detection device (500) according to another embodiment of the present invention.

[0093] like Figure 5As shown, the image sensing device (20) of the joining force detection device (400) according to another part or other embodiments of the present invention may include a first camera (C1) and a second camera (C2); the first camera (C1) is tilted at a first angle (A1) in a first direction (I) with reference to vertically above or vertically below the joining surface (F); the second camera (C2) is tilted at a second angle (A2) different from the first angle (A1) in the first direction (I) with reference to vertically above or vertically below the joining surface (F).

[0094] Therefore, the first angle (A1) and the second angle (A2) as the setting angles of the first camera (C1) and the second camera (C2) as described above can be fixedly set at an angle with optimal recognition ability, that is, according to the wafer (W1) (W2) or substrate under different materials and environments, the angle with optimal recognition ability for various pores, bubbles or foreign objects that may exist on the bonding surface (F) can be fixedly set.

[0095] Therefore, the operator can set the optimal first angle (A1) and second angle (A2) according to different types and shapes of wafers or substrates, thereby greatly improving the recognition and resolution of optical images at different angles.

[0096] Figure 6 is a perspective view conceptually showing a joining force detection device (600) according to another embodiment of the present invention.

[0097] like Figure 6 As shown, the image sensing device (20) of the joining force detection device (600) according to another part or other embodiments of the present invention may include a first camera (C1) and a third camera (C3); the first camera (C1) is tilted at a first angle (A1) in a first direction (I) with reference to vertically above or vertically below the joining surface (F); the third camera (C3) is tilted at a third angle (A3) in a second direction (II) different from the first direction (I) with reference to vertically above or vertically below the joining surface (F).

[0098] Therefore, the first angle (A1) and the third angle (A3) serving as the setting angles of the first camera (C1) and the third camera (C3) can be fixedly set at an angle with optimal recognition ability, that is, according to the wafer (W1) (W2) or substrate under different materials and environments, the angle with optimal recognition ability for various pores, bubbles or foreign objects that may exist on the bonding surface (F) can be fixedly set.

[0099] For example, in order to improve the recognition and resolution of the optical image from different angles, the first direction (I) may be the X-axis direction, and the second direction (II) may be the Y-axis direction. However, this is not limited, and the first direction (I) and the second direction (II) may be completely different directions.

[0100] Therefore, regardless of the pattern, etc., the operator can set the optimal first angle (A1) and third angle (A3) according to different types and shapes of wafers or substrates, thereby greatly improving the recognition and resolution of optical images at different angles.

[0101] Figure 7 It is a side view conceptually showing a joining force detection device (700) according to another embodiment of the present invention.

[0102] like Figure 7 As shown, the image sensing device (20) of the joining force detection device (400) according to another part or other embodiments of the present invention may include a movable camera (C4); with the vertical above or vertical below the joining surface (F) as a reference, the illumination angle of the movable camera (C4) is changed by an angle moving device (M2) that moves from the fourth angle of the first direction (I) to the fifth angle.

[0103] Therefore, by utilizing the continuous angle conversion function of the movable camera (C4), it is possible to receive optical images or three-dimensional optical images with optimal recognition capabilities; that is, according to the wafer (W1) (W2) or substrate under different materials and environments, it is possible to receive optical images or three-dimensional optical images with optimal recognition capabilities of various pores, bubbles or foreign objects that may exist on the bonding surface (F).

[0104] Therefore, regardless of the type and shape of wafers or substrates, the recognition and resolution of 2D or 3D optical images can always be significantly improved according to the optimal angle.

[0105] Figure 8 is a perspective view conceptually showing a joining force detection device (800) according to another embodiment of the present invention.

[0106] like Figure 8 As shown, the bonding force detection device (800) according to another part or other embodiments of the present invention may also include a rotating device (M3), which rotates the wafers (W1) (W2) or substrates bonded to each other so that the optical image can be sensed at different angles.

[0107] Therefore, when the wafer (W1) (W2) or substrate is rotated by using the rotating device (M3), the optical image is received at different angles by the first camera (C1) and the third camera (C3), so that according to the wafer (W1) (W2) or substrate under different materials and environments, an optical image or a three-dimensional optical image with the best recognition ability for various pores, bubbles or foreign objects that may exist on the bonding surface (F) can be received.

[0108] Therefore, regardless of the type and shape of wafers or substrates, the recognition and resolution of 2D or 3D optical images can always be significantly improved according to the optimal angle.

[0109] Fig. 9 is a flow chart showing a method for detecting a joining force according to some embodiments of the present invention.

[0110] like Figures 1 to 9 As shown, the bonding force detection method according to some embodiments of the present invention includes the following steps: (a) a step of irradiating light onto the bonding surfaces of mutually bonded wafers (W1) (W2) or substrates; (b) a step of sensing the optical image of light on the bonding surface (F); and (c) a step of judging the bonding state of the bonding surface (F) based on the optical image by utilizing a past database or a learned artificial intelligence model.

[0111] Among them, as for light, infrared light or short-wave infrared light can be used to pass through the wafer or substrate.

[0112] Fig.10 and Fig.11 1 is a photograph showing an example of an optical image of a bonding detection device (100) according to some embodiments of the present invention.

[0113] like Figures 1 to 10 As shown, according to the present invention, Fig.10 As shown in the left photo of the , the optical image of the visible light state cannot identify the bonding surface (F), while Fig.10 As shown in the photo on the right, optical images using infrared light or short-wave infrared light can identify the bonding force of the bonding surface (F) by the brightness.

[0114] And, if Fig.11 As shown, partial cutting can be used Fig.10 The bonding strength is measured by the ratio, contrast or pattern of the total bright or dark area in the photo on the right.

[0115] However, in the joining force detection device and method of the present invention, obtainable optical images are not limited to these two-dimensional optical images, and various optical images such as three-dimensional images like three-dimensional ultrasonograms may be used.

[0116] Although the present invention has been described with reference to the embodiments shown in the accompanying drawings, this is merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be determined by the technical concept of the appended claims.

[0117] Reference numerals

[0118] W1, W2: Wafer F: Bonding surface

[0119] 10: Light emitting device 20: Image sensing device

[0120] 21: Transmissive sensing device 22: Reflective sensing device

[0121] 23: Overall image sensing device 24: Partial image sensing device

[0122] M1: Scanning transmission device I: First direction

[0123] II: Second direction III: Third direction

[0124] C1: First camera A1: First angle

[0125] C2: Second camera A2: Second angle

[0126] C3: Third Camera A3: Third Angle

[0127] C4: Movable Camera A4: Fourth Angle

[0128] A5: Fifth angle M2: Angle moving device

[0129] M3: Rotating device 30: Control unit

[0130] S1: Brightness sensor S2: Frequency sensor

[0131] S3: Thickness measurement sensor 100-800: Joining force detection device

Claims

1. A joining force detection device, comprising: A light emitting device that irradiates light onto the bonding surfaces of mutually bonded wafers or substrates; an image sensing device, the image sensing device sensing an optical image of the light generated by the light emitting device on the bonding surface; as well as A control unit determines a bonding state of the bonding surface based on the optical image received from the image sensing device.

2. The joining force detection device according to claim 1, wherein: The light includes infrared light or short-wave infrared light.

3. The joining force detection device according to claim 1, wherein: The optical image is a two-dimensional plane image that includes the entire area of ​​the bonding surface and is displayed as a brightness difference of the image according to the difference in partial bonding forces of the bonding surface or the presence or absence of bubbles or foreign matter.

4. The bonding force detection device according to claim 1, wherein: The optical image is a three-dimensional shape image that includes the entire region of the bonding surface and is displayed in three dimensions according to differences in partial surface shapes of the bonding surface or shapes of bubbles or foreign matter.

5. The joining force detection device according to claim 1, wherein: The control unit determines whether the bonding force is defective by judging the optical image based on a standard brightness of the image and a pre-matched bonding force database based on different brightnesses.

6. The joining force detection device according to claim 1, wherein: The control unit includes an artificial intelligence model that learns an image for learning in a deep learning manner and judges the optical image to determine whether the bonding force is defective.

7. The joining force detection device according to claim 1, wherein: The image sensing device is a transmission-type sensing device that senses light that passes through the joint surface, or a reflection-type sensing device that senses light that is reflected by the joint surface.

8. The joining force detection device according to claim 1, wherein: The image sensing device is an overall image sensing device, which is disposed above or below the joint surface and is capable of capturing an overall image of the joint surface.

9. The joining force detection device according to claim 1, wherein: The image sensing device is a partial image sensing device, which takes a partial image of the joining surface by means of a scanning transport device that moves along the joining surface or is capable of moving the joining surface.

10. The joining force detection device according to claim 1, wherein: The control unit receives a brightness signal from a brightness sensor disposed around the wafer or substrate, or receives a brightness signal from the optical image; in order to improve the recognition power of the optical image, a brightness control signal for adjusting the light brightness is transmitted to the light emitting device.

11. The joining force detection device according to claim 1, wherein: The control unit receives a frequency signal from a frequency sensor disposed around the wafer or substrate, or receives a frequency signal from the optical image; in order to improve the recognition power of the optical image, a frequency control signal that changes the light frequency is transmitted to the light emitting device.

12. The joining force detection device according to claim 1, wherein: The control unit receives a thickness signal from a thickness measurement sensor disposed around the wafer or substrate, or receives a thickness signal from the optical image; In order to improve the recognition of the optical image, a control signal corresponding to the thickness of the light brightness or the frequency of the light is transmitted to the light emitting device.

13. The joining force detection device according to claim 1, wherein: The image sensing device is disposed vertically above or vertically below the bonding surface.

14. The bonding force detection device according to claim 1, wherein: The image sensing device includes a first camera, which is tilted at a first angle in a first direction with reference to a position vertically above or vertically below the joint surface.

15. The joining force detection device according to claim 14, wherein: The image sensing device includes a second camera, which is tilted at a second angle different from the first angle in the first direction, with reference to vertically above or vertically below the joint surface.

16. The joining force detection device according to claim 14, wherein: The image sensing device includes a third camera, and the third camera is obliquely arranged at a third angle in a second direction different from the first direction with reference to a direction vertically above or vertically below the joint surface.

17. The joining force detection device according to claim 1, wherein: The image sensing device includes a movable camera, and the illumination angle of the movable camera is changed by an angle moving device that moves from a fourth angle in the first direction to a fifth angle based on vertically above or vertically below the joint surface.

18. The joining force detection device according to claim 1, wherein: The bonding force detection device further includes a rotating device that rotates the wafers or substrates bonded to each other so as to sense the optical image at different angles.

19. A method for detecting a joining force, the method comprising: (a) irradiating light onto the bonding surfaces of wafers or substrates bonded to each other; (b) a step of sensing an optical image of the light at the bonding surface; as well as (c) A step of determining the bonding state of the bonding surface based on the optical image using a past database or a learned artificial intelligence model.

20. A joining force detection device, comprising: A light emitting device that irradiates light onto the bonding surfaces of mutually bonded wafers or substrates; an image sensing device, the image sensing device sensing an optical image of the light generated by the light emitting device on the bonding surface; as well as a control unit that determines a bonding state of the bonding surface based on the optical image received from the image sensing device, The light comprises infrared light or short-wave infrared light, The optical image is a two-dimensional plane image, which includes the entire area of ​​the bonding surface and is displayed in a brightness difference of the image according to the difference in partial bonding force of the bonding surface or the presence or absence of bubbles or foreign matter; or the optical image is a three-dimensional shape image, which includes the entire area of ​​the bonding surface and is displayed in three dimensions according to the difference in partial surface shape of the bonding surface or the shape of bubbles or foreign matter, The control unit judges the optical image based on the standard brightness of the image and according to a pre-matched database of bonding forces based on different brightnesses, thereby determining whether the bonding force is poor; or the control unit includes an artificial intelligence model, which learns the image for learning in a deep learning manner, and judges the optical image to determine whether the bonding force is poor.

Images