CN117080144B - High-precision wafer alignment device and method - Google Patents

High-precision wafer alignment device and method Download PDF

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Publication number
CN117080144B
CN117080144B CN202311329472.7A CN202311329472A CN117080144B CN 117080144 B CN117080144 B CN 117080144B CN 202311329472 A CN202311329472 A CN 202311329472A CN 117080144 B CN117080144 B CN 117080144B
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wafer
alignment marks
alignment
coordinates
visual
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CN117080144A (en
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任潮群
王念
闫鑫
陈泳
崔国江
崔建敏
杨冬野
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Xinhui Lianxin Suzhou Technology Co ltd
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Suzhou Xinhuilian Semiconductor Technology Co ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/68—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for positioning, orientation or alignment
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/68—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for positioning, orientation or alignment
    • H01L21/681—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for positioning, orientation or alignment using optical controlling means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

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  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
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  • Microelectronics & Electronic Packaging (AREA)
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  • Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)

Abstract

The invention belongs to the field of semiconductor processing and manufacturing, and provides a high-precision wafer alignment device and a high-precision wafer alignment method, wherein the device comprises an uploading platform, a downloading platform, a visual structure, an optical structure and a control structure, wherein a first driving component is arranged on the uploading platform, and a second driving component is arranged on the downloading platform; the visual structure comprises two groups of visual components which are identical in structure and mirror symmetry, each visual component comprises a visual camera and an illumination light source, and the visual cameras obtain alignment marks on the wafer; the optical structure comprises two groups of optical components, wherein the optical components comprise a three-dimensional spectroscope and a right-angle plane reflector; the control structure is respectively communicated with the vision camera, the first driving component and the second driving component and is used for outputting an alignment instruction for driving the first driving component and/or the second driving component to move according to the alignment mark. The invention can solve the technical problem that the alignment accuracy of the upper and lower wafers is affected by the fact that the coaxial error and the motion repeatability error of the upper and lower visual components cannot be eliminated through compensation in the existing alignment method.

Description

High-precision wafer alignment device and method
Technical Field
The invention belongs to the field of semiconductor processing and manufacturing, relates to a wafer bonding technology, and in particular relates to a high-precision wafer alignment device and method.
Background
Advanced packaging techniques based on heterogeneous integration and vertical interconnect applications are rapidly evolving as the concept of surpassing moles is further widely appreciated. With the continuous maturation and perfection of the technologies such as bumping, TSV (through silicon via), RDL (redistribution layer), etc., the requirements of wafer bonding technology are also continuously increasing.
The wafer alignment bonding operation mainly combines two wafers in the vertical direction to realize signal interconnection between the two wafers, and the most important and difficult part in the wafer alignment bonding operation is how to realize high-precision alignment of the two wafers. Currently, in order to achieve high precision alignment, the common practice is:
the upper and lower wafers are respectively adsorbed on an upper and lower loading table, the upper loading table is provided with a XXYY four-direction movement mechanism for realizing translation and rotation, and the lower loading table can move along the Y direction; two groups of visual and optical components of C-shaped structures are symmetrically arranged on the left side and the right side of the upper downloading table, a group of symmetrical optical lenses are respectively arranged at the upper end part and the lower end part of the opening side of the C-shaped structures, and left and right alignment marks of upper and lower wafers can be respectively read; when the alignment operation is carried out, firstly, the downloading table is moved to an alignment position, the alignment mark of the lower wafer is moved to the visual field of the vision and optical assembly, and the position is read and recorded; secondly, the downloading table is moved out, the uploading table is moved to an alignment position, the alignment mark of the upper wafer is moved to the visual field of the vision and optical assembly, and the position is read and recorded; and finally, moving the downloading table back to the alignment position, calculating the angle and displacement deviation between the upper wafer and the lower wafer, and compensating the uploading table through rotation and displacement movement to finish the alignment.
The wafer alignment operation described above has the following fixed errors:
1. taking the left side alignment mark as an example, the left side alignment mark of the upper wafer is identified by the lower visual component, the left side alignment mark of the lower wafer is identified by the upper visual component, and at the moment, although the upper visual component and the lower visual component are connected through a C-shaped structure, the deviation generated by the relative motion of the upper visual component and the lower visual component can be eliminated, but the coaxial error of the installation of the upper visual component and the lower visual component cannot be completely eliminated;
pitching deflection of the C-shaped structure at different positions can lead to further expansion of coaxial errors of the upper visual component and the lower visual component;
3. after the left and right alignment marks of the lower wafer are read, the downloading table needs to be moved and withdrawn, and the downloading table is moved back after the left and right alignment marks of the upper wafer are read, so that repeatability errors exist in the front and back movement of the downloading table;
4. the calculated angle and displacement deviation between the upper and lower wafers can be compensated by the movement of the uploading table, but the alignment result after compensation cannot be identified, and the error existing in the compensation movement process of the uploading table cannot be reduced.
In general, the above alignment method has problems of an alignment error and a motion repeatability error of the upper and lower vision components, which cannot be eliminated by compensation, thereby affecting alignment accuracy between the upper and lower wafers.
Disclosure of Invention
The invention discloses a high-precision wafer alignment device and method, aiming at solving the technical problem that the alignment precision of upper and lower wafers is affected because the coaxial error and the motion repeatability error of the upper and lower visual components cannot be eliminated through compensation in the existing alignment method.
The technical scheme for realizing the aim of the invention is as follows:
the embodiment of the invention provides a high-precision wafer alignment device, which comprises:
the device comprises a carrying platform, a first driving assembly and a second driving assembly, wherein the carrying platform comprises an upper carrying platform for loading an upper wafer and a lower carrying platform for loading a lower wafer, the upper carrying platform is provided with the first driving assembly for driving the upper carrying platform to translate and rotate, and the lower carrying platform is provided with the second driving assembly for driving the lower carrying platform to translate and rotate;
the visual structure is positioned at two sides of the carrier and comprises two groups of visual components which are identical in structure and mirror symmetry, and each visual component comprises a visual camera and an illumination light source;
the optical structure and the visual structure are both positioned on the same side of the carrier, the optical structure comprises two groups of optical components which have the same structure and are in mirror symmetry, and the optical components comprise a three-dimensional spectroscope and a right-angle plane reflector; the three-dimensional spectroscope divides light emitted by the illumination light source positioned on the same side into two beams of light through transmission and reflection, one beam of transmitted light irradiates the alignment mark of the upper wafer, and the other beam of reflected light irradiates the right-angle plane mirror and irradiates the alignment mark of the lower wafer after light path conversion; the vision camera acquires the alignment marks of the upper wafer and the lower wafer displayed by the three-dimensional spectroscope;
and the control structure is respectively communicated with the vision camera, the first driving assembly and the second driving assembly and is used for outputting an alignment instruction for driving the first driving assembly and/or the second driving assembly to move according to the alignment mark.
Further, the transmittance of the stereoscopic spectroscope is 40-60%, the reflectance is 40-60%, and preferably, the transmittance and the reflectance of the stereoscopic spectroscope are both 50%.
Further, in the right angle type plane mirror, one plane mirror close to the stereoscopic spectroscope is perpendicular to the carrying platform, and one plane mirror far away from the stereoscopic spectroscope is parallel to the carrying platform.
Further, the two alignment marks of the upper wafer and the lower wafer are respectively, and the distance between the two alignment marks of the upper wafer is the same as the distance between the two alignment marks of the lower wafer, and is c;
after the upper wafer is loaded on the loading table and moved to a set position, the two alignment marks respectively fall into the visual field range of the vision camera in each group of vision components;
after the lower wafer is loaded on the downloading table and moved to a set position, the two alignment marks respectively fall into the visual field range of the vision camera in each group of vision components.
Further, the distances of the visual field coordinate centers of the two visual cameras in the world coordinate system include a distance a in the X direction and a distance b in the Y direction, wherein a 2 +b 2 =c 2 。
Further, the first driving assembly comprises a group of XXY-direction first macro motors and a group of XXYY-direction micro motors, and the group of XXY-direction first macro motors and the group of XXYY-direction micro motors drive the uploading platform to horizontally translate and rotate;
the second driving assembly comprises a group of XXY-direction second macro motors and a group of Z-direction motors, the group of XXY-direction second macro motors drive the downloading table to translate and rotate left and right, and the group of Z-direction motors drive the downloading table to translate up and down.
Still further, the group of Z-direction motors is composed of at least 3 motors arranged circumferentially on the downloading table, and the uploading table is provided with laser ranging sensors in one-to-one correspondence with the motors.
The embodiment of the invention also provides a high-precision wafer alignment method, which comprises the following steps:
s1, loading an upper wafer on an upper loading table and loading a lower wafer on a lower loading table;
s2, horizontally moving and rotating the uploading table to enable the two alignment marks of the upper wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks, and respectively recording the coordinates of the two alignment marks of the upper wafer through the vision camera;
s3, translating the downloading table to a direction close to the uploading table, translating and rotating the downloading table left and right to enable the two alignment marks of the lower wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks of the lower wafer respectively, and recording the coordinates of the two alignment marks of the wafer respectively through the vision camera;
s4, outputting a compensation angle Rz between the upper wafer and the lower wafer according to the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, enabling the upper carrier to horizontally rotate by the compensation angle Rz, and acquiring the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer again;
s5, according to the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer, respectively obtaining an X-direction compensation distance delta X and a Y-direction compensation distance delta Y of the upper wafer and the lower wafer, horizontally translating the upper wafer by the X-direction compensation distance delta X and the Y-direction compensation distance delta Y, and obtaining the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer again;
s6, repeating the steps S4 and S5 until the deviation between the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer is within the preset deviation, and completing the alignment operation of the upper wafer and the lower wafer.
Further, in steps S2 to S6, the method for acquiring the coordinates of the alignment mark includes:
illuminating light through the illumination source of the visual structure onto the optical structure;
the three-dimensional spectroscope of the optical structure transmits and reflects the received light, the transmitted light irradiates the alignment mark of the upper wafer, the reflected light irradiates the right-angle plane mirror of the optical structure and irradiates the alignment mark of the lower wafer after the light path is changed;
and the vision camera of the vision structure acquires images of the alignment marks of the upper wafer and the lower wafer displayed by the three-dimensional spectroscope, and then the coordinates of the alignment marks are obtained.
Further, in step S4, a compensation angle Rz between the upper wafer and the lower wafer is output according to the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, including;
the coordinates of the two alignment marks of the upper wafer are (X1 l, Y1 l) and (X1 r, Y1 r), respectively, defining an angle α=arctan ((Y1 r-y1l+b)/(X1 r-x1l+a)) of the upper wafer;
the coordinates of the two alignment marks of the lower wafer are (X2 l, Y2 l) and (X2 r, Y2 r) respectively, and an angle beta=arctan ((Y2 r-Y2 l+b)/(X2 r-X2 l+a)) of the lower wafer is defined, wherein a is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the X direction in the world coordinate system, b is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the Y direction in the world coordinate system, X1l and X1r are the coordinates of the two alignment marks of the upper wafer in the X direction respectively, Y1l and Y1r are the coordinates of the two alignment marks of the upper wafer in the Y direction respectively, and X2l and X2r are the coordinates of the two alignment marks of the lower wafer in the X direction respectively;
and obtaining the compensation angle Rz between the upper wafer and the lower wafer according to the formula beta-alpha.
Further, in step S3, the distance between the upper stage and the lower stage is measured by a plurality of laser ranging sensors circumferentially arranged on the upper stage, and the lower stage is translated in a direction approaching the upper stage, so that the upper wafer and the lower wafer are parallel.
Compared with the prior art, the beneficial effects that above-mentioned at least one technical scheme that this description embodiment adopted can reach include at least:
1. in the wafer alignment device designed by the invention, the coordinates of the alignment marks on the upper wafer and the lower wafer can be obtained simultaneously through the visual components and the optical components which are positioned on the same side of the carrier, and the coaxial deviation of the alignment mode of respectively reading the alignment marks by the upper and lower visual components in the traditional structure can be eliminated;
2. in the wafer alignment device designed by the invention, the visual structure does not need to move, so that the deviation of pitching deflection and the like caused by the movement of the visual component in the traditional structure is greatly reduced;
3. in the wafer alignment device designed by the invention, when the angle Rz between the upper wafer and the lower wafer, the X-direction compensation distance delta X and the Y-direction compensation distance delta Y are compensated only by horizontally moving and rotating the upper stage, the repeated positioning error caused by the motion of the lower stage in the traditional structure can be eliminated without the motion of the lower stage.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a high-precision wafer alignment apparatus according to an embodiment of the present invention;
FIG. 2 is a flow chart of a high precision wafer alignment method according to an embodiment of the present invention;
1, an uploading table; 2. a downloading table; 3. a vision component; 4. an optical component; 41. a three-dimensional spectroscope; 42. a right angle planar mirror; 11. a wafer is arranged on the upper wafer; 12. and (5) lower wafer.
Detailed Description
Embodiments of the present application are described in detail below with reference to the accompanying drawings.
Other advantages and effects of the present application will become apparent to those skilled in the art from the present disclosure, when the following description of the embodiments is taken in conjunction with the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. The present application may be embodied or carried out in other specific embodiments, and the details of the present application may be modified or changed from various points of view and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features of the embodiments may be combined with each other without conflict. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.
The embodiment of the invention provides a high-precision wafer alignment device, which comprises: stage, visual structure, optical structure and control structure.
Referring to fig. 1, the carrier comprises an upper carrier 1 for loading an upper wafer 11 and a lower carrier 2 for loading a lower wafer 12, wherein a first driving component for driving the upper carrier 1 to translate and rotate is arranged on the upper carrier 1, and a second driving component for driving the lower carrier 2 to translate and rotate is arranged on the lower carrier 2. In practice, the upper wafer 11 may be loaded on the lower surface of the upper stage 1 by adsorption, and the lower wafer 12 may be loaded on the upper surface of the lower stage 2 by adsorption. Meanwhile, in order to prevent the upper wafer 11 and the lower wafer 12 from falling off from the respective carriers or from moving relatively in position during movement, a structure such as a limit groove, a clamping member, etc. may be provided on the carriers.
In a specific implementation, the two alignment marks of the upper wafer 11 and the lower wafer 12 are both two, and the distance between the two alignment marks of the upper wafer 11 is the same as the distance between the two alignment marks of the lower wafer, which is c.
In one embodiment, not shown in the drawings, the first driving assembly includes a set of first macro motors in the XXY direction and a set of micro motors in the XXY direction, and the set of first macro motors in the XXY direction and the set of micro motors in the XXY direction both drive the uploading platform to translate and rotate left and right. In particular, a group of XXY-direction first macro motors may be 3 first macro motors, where two first macro motors are disposed in the X direction of the upper stage 1, and 1 macro motor is disposed in the Y direction, and the first macro motors are mainly used to move and rotate the upper stage 1 left and right to perform coarse adjustment on the position of the upper wafer 11. A group of XXYY direction micro motors can select 4 micro motors, two micro motors are respectively arranged in the X direction and the Y direction of the upper carrying platform 1, and the micro motors are mainly used for horizontally moving and rotating the upper carrying platform 1 to finely adjust the position of the upper wafer 11.
The second driving assembly comprises a group of XXY-direction second macro motors and a group of Z-direction motors, the group of XXY-direction second macro motors drive the downloading table to translate and rotate left and right, and the group of Z-direction motors drive the downloading table to translate up and down. In particular, 3 second macro motors may be selected as a set of the second macro motors in the XXY direction, two second macro motors are disposed in the X direction of the downloading table 2, and 1 second macro motor is disposed in the Y direction, and the second macro motors are mainly used for moving the downloading table 2 to perform coarse adjustment on the position of the lower wafer 12.
Wherein, a group of Z-direction motors mainly move the downloading table 2 up and down along the direction approaching to or separating from the uploading table 1. Still further, the group of Z-direction motors is composed of at least 3 motors circumferentially arranged on the downloading table 2, and the uploading table 1 is provided with laser ranging sensors in one-to-one correspondence with the motors. In the implementation, the motors at different positions work to enable the uploading platform 1 to translate upwards or downwards, and the laser ranging sensor can monitor the distance between the uploading platform 1 and the downloading platform 2 in real time, so that the motors are mutually matched to ensure that the uploading platform 1 and the downloading platform 2 are kept parallel.
Referring to fig. 1, the vision structure is located at two sides of the carrier, and includes two groups of vision components 3 with identical structures and mirror symmetry, which may be named as a left side vision component and a right side vision component, respectively. The vision assembly 3 comprises a vision camera and an illumination light source. The vision camera is used to capture the alignment marks of the upper wafer 11 and the lower wafer 12 displayed on the stereo beam splitter 41 of the optical assembly 4 described below, resulting in coordinates. The illumination light source is used to emit light, and irradiates alignment marks of the upper wafer 11 and the lower wafer 12 after being transmitted and reflected by the optical assembly 4 described below.
Preferably, the vision assembly 3 further includes an objective lens, which is disposed between the illumination light source and a stereo spectroscope 41 of the optical assembly 4 described below, and can amplify an alignment mark displayed on the stereo spectroscope 41, so as to ensure that the vision camera accurately acquires coordinates in an image.
In practice, after the upper wafer 11 is assembled to the upper stage 1 and moved to a set position, it is necessary to ensure that two alignment marks fall within the field of view of the vision cameras in each group of the vision components 3. Similarly, after the lower wafer 12 is assembled to the downloading table 2 and moved to a set position, the two alignment marks need to fall within the field of view of the vision cameras in each group of the vision components 3.
In particular, the distances between the visual field coordinate centers of the two vision cameras in the world coordinate system include a distance a in the X direction and a distance b in the Y direction, wherein a 2 +b 2 =c 2 。
Referring to fig. 1, the optical structure and the vision structure are both located on the same side of the stage, and the optical structure includes two groups of optical components 4 that are identical in structure and mirror symmetry, which may be respectively named as a left-side optical component and a right-side optical component. The optical assembly 4 includes a stereo beam splitter 41 and a right angle planar mirror 42.
In specific implementation, referring to fig. 1, the illumination light source is configured to emit light to the stereo beam splitter 41, the stereo beam splitter 41 divides the light emitted by the illumination light source on the same side into two beams of light through transmission and reflection, one beam of light irradiates the alignment mark of the upper wafer 11, and the other beam of reflected light irradiates the alignment mark of the lower wafer 12 after the light path conversion on the right angle plane mirror 42; meanwhile, the vision camera collects alignment marks of the upper wafer 11 and the lower wafer 12 displayed through the stereoscopic spectroscope.
In practice, the transmittance of the stereo beam splitter 41 may be selected to be 40-60%, the reflectance is 40-60%, preferably, the transmittance and the reflectance of the stereo beam splitter 41 are both 50%, that is, the transmittance/reflectance ratio is 50/50, and the brightness of the alignment marks of the upper wafer 11 and the lower wafer 12 obtained by the vision camera may be kept substantially the same by performing 1:1 transmission and reflection of the light emitted by the illumination light source.
In the implementation, referring to fig. 1, one of the right-angle planar mirrors 42, which is close to the stereo beam splitter 41, is perpendicular to the carrier, and one of the right-angle planar mirrors, which is far from the stereo beam splitter 41, is parallel to the carrier.
In a specific implementation, the control structure is respectively communicated with the vision camera, the first driving component and the second driving component and is used for outputting an alignment instruction for driving the first driving component and/or the second driving component to move according to the alignment mark.
The wafer alignment device in the embodiment of the invention has the following advantages:
1. the alignment mark coordinates on the upper wafer and the lower wafer can be obtained simultaneously through the visual components and the optical components which are positioned on the same side of the carrier, so that the coaxial deviation of the alignment mark alignment mode of the upper and lower visual components respectively read in the traditional structure can be eliminated;
2. the visual structure does not need to move, so that the deviation of pitching deflection and the like caused by movement of the visual component in the traditional structure is greatly reduced;
3. when the angle Rz, the X-direction compensation distance delta X and the Y-direction compensation distance delta Y between the upper wafer 11 and the lower wafer 12 are compensated only by horizontally moving and rotating the upper loading table 1, the repeated positioning error caused by the movement of the loading table 2 in the traditional structure can be eliminated without the movement of the loading table 2;
4. by setting a group of Z-direction motors and laser ranging sensors, parallelism between the uploading table 1 and the downloading table 2 can be ensured, and alignment accuracy is improved.
The embodiment of the invention also provides a high-precision wafer alignment method, which is shown in fig. 2 and comprises the following steps:
s1, loading an upper wafer on an upper stage, and loading a lower wafer on a lower stage, wherein the upper wafer and the lower wafer can be arranged on the respective stages in a manner of adsorption, clamping and the like when the method is concretely implemented.
S2, translating and rotating the uploading table left and right, enabling the two alignment marks of the upper wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks, and recording the coordinates of the two alignment marks of the upper wafer through the vision camera.
And S3, translating the downloading table to a direction close to the uploading table, translating and rotating the downloading table left and right, enabling the two alignment marks of the lower wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks, and recording the coordinates of the two alignment marks of the wafer through the vision camera.
In specific implementation, the high-precision wafer alignment device can be used for enabling an alignment mark on a wafer to fall into the visual field of a vision camera by firstly using a first macro motor in the XXY direction to horizontally move an uploading table (or a second macro motor in the XXY direction to horizontally move a downloading table); and then horizontally rotating the uploading platform by using the first macro motor in the XXY direction (or rotating the downloading platform by using the second macro motor in the XXY direction) so that another alignment mark on the wafer falls into the visual field of the vision camera.
In specific implementation, the method for judging whether the alignment mark is in the visual field of the vision camera comprises the following steps: the light emitted by the illumination light source irradiates the alignment mark after passing through the optical structure, the light-passing path can be collected by the vision camera and returned to the alignment mark on the optical structure, when the light can be collected, the light is indicated to be in the visual field range of the vision camera, and when the light cannot be collected, the light is indicated to be outside the visual field range of the vision camera, and the position of the carrier is required to be adjusted.
And S4, outputting a compensation angle Rz between the upper wafer and the lower wafer according to the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, enabling the upper carrier to horizontally rotate by the compensation angle Rz, and acquiring the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer again.
When the coordinates of the two alignment marks of the upper wafer and the lower wafer are obtained respectively, an included angle alpha between the connecting line of the two alignment marks of the upper wafer and the horizontal direction in the image and an included angle beta between the connecting line of the two alignment marks of the lower wafer and the horizontal direction in the image can be obtained, a compensation angle Rz required to be rotated by the upper wafer can be obtained through the difference value of the two included angles, the upper loading platform can be rotated according to the compensation angle Rz by using the micro motor, and when the connecting line of the two alignment marks of the upper wafer and the lower wafer are parallel to each other after rotation, the following step S5 is needed to enable the two connecting lines to coincide, and alignment between the upper wafer and the lower wafer can be realized after the two connecting lines coincide.
S5, according to the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer, the X-direction compensation distance delta X and the Y-direction compensation distance delta Y of the upper wafer and the lower wafer are obtained respectively, the upper wafer horizontally translates the X-direction compensation distance delta X and the Y-direction compensation distance delta Y, and the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer are obtained again.
In the implementation, the translation amounts of the upper wafer in the X direction and the Y direction can be calculated through the coordinates of the 4 alignment marks, and then the upper loading platform is translated through the micro motor according to the compensation distance delta Y and the compensation distance delta X, so that the connecting line of the two alignment marks of the upper wafer and the lower wafer are preliminarily overlapped.
S6, repeating the steps S4 and S5 until the deviation between the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer is within a preset deviation (namely, the minimum progress of the micro motor), and completing the alignment operation of the upper wafer and the lower wafer.
Further, in steps S2 to S6, the method for acquiring the coordinates of the alignment mark includes:
illuminating light through the illumination source of the visual structure onto the optical structure;
the three-dimensional spectroscope of the optical structure transmits and reflects the received light, the transmitted light irradiates the alignment mark of the upper wafer, the reflected light irradiates the right-angle plane mirror of the optical structure and irradiates the alignment mark of the lower wafer after the light path is changed;
and the vision camera of the vision structure acquires images of the alignment marks of the upper wafer and the lower wafer displayed by the three-dimensional spectroscope, and then the coordinates of the alignment marks are obtained.
Further, in step S4, a compensation angle Rz between the upper wafer and the lower wafer is output according to the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, including;
the coordinates of the two alignment marks of the upper wafer are (X1 l, Y1 l) and (X1 r, Y1 r), respectively, defining an angle α=arctan ((Y1 r-y1l+b)/(X1 r-x1l+a)) of the upper wafer;
the coordinates of the two alignment marks of the lower wafer are (X2 l, Y2 l) and (X2 r, Y2 r) respectively, and an angle beta=arctan ((Y2 r-Y2 l+b)/(X2 r-X2 l+a)) of the lower wafer is defined, wherein a is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the X direction in the world coordinate system, b is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the Y direction in the world coordinate system, X1l and X1r are the coordinates of the two alignment marks of the upper wafer in the X direction respectively, Y1l and Y1r are the coordinates of the two alignment marks of the upper wafer in the Y direction respectively, and X2l and X2r are the coordinates of the two alignment marks of the lower wafer in the X direction respectively;
and obtaining the compensation angle Rz between the upper wafer and the lower wafer according to the formula beta-alpha.
In a modified embodiment, in the step S3, in order to ensure that the upper wafer 11 and the lower wafer 12 are spatially parallel, the distance between the upper stage 1 and the lower stage 2 is measured by a plurality of laser ranging sensors circumferentially arranged on the upper stage 1, so as to ensure that the upper wafer and the lower wafer are parallel when the lower stage 2 translates in a direction approaching the upper stage 1.
According to the high-precision wafer alignment method provided by the embodiment of the invention, the alignment marks on the same sides of the upper wafer and the lower wafer are simultaneously identified through one group of vision components on one side, so that the coaxial error of two groups of vision components in the traditional C-shaped structure is eliminated; and the vision component is utilized to read the alignment mark positions of the upper wafer and the lower wafer again after the upper loading table is compensated, and the error caused by the movement of the upper loading table and the lower loading table is reduced through multiple times of compensation.
It will be apparent to those skilled in the art that the foregoing is merely a preferred embodiment of the present invention and is not intended to limit the invention, and that various modifications and variations can be made to the embodiment of the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. A high precision wafer alignment apparatus, comprising:
the device comprises a carrying platform, a first driving assembly and a second driving assembly, wherein the carrying platform comprises an upper carrying platform for loading an upper wafer and a lower carrying platform for loading a lower wafer, the upper carrying platform is provided with the first driving assembly for driving the upper carrying platform to translate and rotate, and the lower carrying platform is provided with the second driving assembly for driving the lower carrying platform to translate and rotate;
the visual structure is positioned at two sides of the carrier and comprises two groups of visual components which are identical in structure and mirror symmetry, and each visual component comprises a visual camera and an illumination light source;
the optical structure and the visual structure are both positioned on the same side of the carrier, the optical structure comprises two groups of optical components which have the same structure and are in mirror symmetry, and the optical components comprise a three-dimensional spectroscope and a right-angle plane reflector; the three-dimensional spectroscope divides light emitted by the illumination light source positioned on the same side into two beams of light through transmission and reflection, one beam of transmitted light irradiates the alignment mark of the upper wafer, and the other beam of reflected light irradiates the right-angle plane mirror and irradiates the alignment mark of the lower wafer after light path conversion; the vision camera acquires the alignment marks of the upper wafer and the lower wafer displayed by the three-dimensional spectroscope;
and the control structure is respectively communicated with the vision camera, the first driving assembly and the second driving assembly and is used for outputting an alignment instruction for driving the first driving assembly and/or the second driving assembly to move according to the alignment mark.
2. The high-precision wafer alignment apparatus according to claim 1, wherein the transmittance of the three-dimensional spectroscope is 40-60%, and the reflectance is 40-60%.
3. The high precision wafer alignment apparatus of claim 1, wherein one of the right angle type plane mirrors, which is close to the stereo beam splitter, is perpendicular to the carrier, and one of the plane mirrors, which is far from the stereo beam splitter, is parallel to the carrier.
4. The high-precision wafer alignment apparatus according to claim 1, wherein the alignment marks of the upper wafer and the lower wafer are both two, and a distance between the alignment marks of the upper wafer is the same as a distance between the alignment marks of the lower wafer, both being c;
after the upper wafer is loaded on the loading table and moved to a set position, the two alignment marks respectively fall into the visual field range of the vision camera in each group of vision components;
after the lower wafer is loaded on the downloading table and moved to a set position, the two alignment marks respectively fall into the visual field range of the vision camera in each group of vision components.
5. The high precision wafer alignment apparatus of claim 4, wherein the distances of the vision coordinate centers of the two vision cameras in the world coordinate system include a distance a in the X-direction and a distance b in the Y-direction, wherein a 2 +b 2 =c 2 。
6. The high precision wafer alignment apparatus of claim 1, wherein the first drive assembly comprises a set of XXY-direction first macro-motors and a set of XXYY-direction micro-motors, each of the set of XXY-direction first macro-motors and the set of XXYY-direction micro-motors translating and rotating the upload stage left and right;
the second driving assembly comprises a group of XXY-direction second macro motors and a group of Z-direction motors, the group of XXY-direction second macro motors drive the downloading table to horizontally move and rotate, and the group of Z-direction motors drive the downloading table to horizontally move up and down;
wherein, the first macro motor in the XXY direction means that two first macro motors are arranged in the X direction and one first macro motor is arranged in the Y direction; the XXY direction second macro motor means that two second macro motors are arranged in the X direction and one second macro motor is arranged in the Y direction; XXYY-direction micro motors mean that two micro motors are respectively arranged in the X-direction and the Y-direction of the upload stage.
7. The high-precision wafer alignment apparatus according to claim 6, wherein the set of Z-direction motors is composed of at least 3 motors arranged circumferentially on the downloading stage, and the uploading stage is provided with laser ranging sensors in one-to-one correspondence with the motors.
8. A high precision wafer alignment method, comprising:
s1, loading an upper wafer on an upper loading table and loading a lower wafer on a lower loading table;
s2, horizontally moving and rotating the uploading table to enable the two alignment marks of the upper wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks, and respectively recording the coordinates of the two alignment marks of the upper wafer through the vision camera;
s3, translating the downloading table to a direction close to the uploading table, translating and rotating the downloading table left and right to enable the two alignment marks of the lower wafer to fall into the visual field range of the vision camera corresponding to the positions of the two alignment marks of the lower wafer respectively, and recording the coordinates of the two alignment marks of the wafer respectively through the vision camera;
s4, outputting a compensation angle Rz between the upper wafer and the lower wafer according to the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, enabling the upper carrier to horizontally rotate by the compensation angle Rz, and acquiring the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer again;
s5, according to the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer, respectively obtaining an X-direction compensation distance delta X and a Y-direction compensation distance delta Y of the upper wafer and the lower wafer, horizontally translating the upper wafer by the X-direction compensation distance delta X and the Y-direction compensation distance delta Y, and obtaining the obtained coordinates of the two alignment marks of the upper wafer and the obtained coordinates of the two alignment marks of the lower wafer again;
s6, repeating the steps S4 and S5 until the deviation between the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer is within a preset deviation, and completing the alignment operation of the upper wafer and the lower wafer;
in steps S2 to S6, the method for acquiring the coordinates of the alignment mark includes:
illuminating light through the illumination source of the visual structure onto the optical structure;
the three-dimensional spectroscope of the optical structure transmits and reflects the received light, the transmitted light irradiates the alignment mark of the upper wafer, the reflected light irradiates the right-angle plane mirror of the optical structure and irradiates the alignment mark of the lower wafer after the light path is changed;
and the vision camera of the vision structure acquires images of the alignment marks of the upper wafer and the lower wafer displayed by the three-dimensional spectroscope, and then the coordinates of the alignment marks are obtained.
9. The method according to claim 7, wherein in step S4, the compensating angle Rz between the upper wafer and the lower wafer is outputted based on the coordinates of the two alignment marks of the upper wafer and the coordinates of the two alignment marks of the lower wafer, comprising;
the coordinates of the two alignment marks of the upper wafer are (X1 l, Y1 l) and (X1 r, Y1 r), respectively, defining an angle α=arctan ((Y1 r-y1l+b)/(X1 r-x1l+a)) of the upper wafer;
the coordinates of the two alignment marks of the lower wafer are (X2 l, Y2 l) and (X2 r, Y2 r) respectively, and an angle beta=arctan ((Y2 r-Y2 l+b)/(X2 r-X2 l+a)) of the lower wafer is defined, wherein a is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the X direction in the world coordinate system, b is the distance between the visual field coordinate centers of the two visual cameras in the visual structure in the Y direction in the world coordinate system, X1l and X1r are the coordinates of the two alignment marks of the upper wafer in the X direction respectively, Y1l and Y1r are the coordinates of the two alignment marks of the upper wafer in the Y direction respectively, and X2l and X2r are the coordinates of the two alignment marks of the lower wafer in the X direction respectively;
and obtaining the compensation angle Rz between the upper wafer and the lower wafer according to the formula beta-alpha.
CN202311329472.7A 2023-10-16 2023-10-16 High-precision wafer alignment device and method Active CN117080144B (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111584415A (en) * 2020-06-22 2020-08-25 中国科学院长春光学精密机械与物理研究所 Alignment system for wafer bonding
CN113271405A (en) * 2021-07-14 2021-08-17 杭州长川科技股份有限公司 Wafer calibration camera and probe station with same
CN114793466A (en) * 2021-10-25 2022-07-26 长江存储科技有限责任公司 Wafer bonding apparatus and method
CN115831844A (en) * 2022-11-24 2023-03-21 北京华卓精科科技股份有限公司 Wafer alignment method and alignment device
CN116759360A (en) * 2023-08-18 2023-09-15 苏州芯慧联半导体科技有限公司 Wafer alignment device and lens error calibration method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111584415A (en) * 2020-06-22 2020-08-25 中国科学院长春光学精密机械与物理研究所 Alignment system for wafer bonding
CN113271405A (en) * 2021-07-14 2021-08-17 杭州长川科技股份有限公司 Wafer calibration camera and probe station with same
CN114793466A (en) * 2021-10-25 2022-07-26 长江存储科技有限责任公司 Wafer bonding apparatus and method
CN115831844A (en) * 2022-11-24 2023-03-21 北京华卓精科科技股份有限公司 Wafer alignment method and alignment device
CN116759360A (en) * 2023-08-18 2023-09-15 苏州芯慧联半导体科技有限公司 Wafer alignment device and lens error calibration method

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