Pre-alignment instrument and alignment method

Abstract

The invention relates to the technical field of semiconductor processing, and discloses a pre-alignment instrument and an alignment method. A long-strip-shaped hole extending in the first direction is formed in the carrying table. The supporting assembly comprises a first supporting column and a supporting part, the supporting part comprises two second supporting columns, the two second supporting columns are distributed on the two sides of the long-strip-shaped hole in the second direction, and the first supporting column and the two second supporting columns are used for supporting the wafer; the adjusting assembly comprises a tray and a driving part, the driving part is located below the carrying table, the driving part is provided with an output shaft, the output shaft penetrates through the long-strip-shaped hole and is connected to the tray, the tray is used for bearing and adsorbing the wafer, and the driving part is used for driving the tray to move; the detection device is arranged above the alignment device and comprises a shell and a camera, the camera is installed in the shell, an avoiding hole is formed in the bottom wall of the shell, and the camera can penetrate through the avoiding hole to irradiate the edge, close to the first supporting column, of the wafer.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing, and in particular to a pre-alignment instrument and an alignment method. Background Art

[0002] The common pre-aligners currently on the market connect the main body and the camera part through a support shaft to form a C-shaped structure. The wafer is pre-aligned in the middle position. Due to the existence of the support shaft, the distance between the camera and the main body is relatively fixed. When the space requirement is large or there is a requirement for no obstruction in all four directions, the structure of the traditional pre-aligner will form a limitation. Furthermore, after the existing pre-aligner identifies the center deviation of the wafer, it uses a robotic arm to compensate for the position, and then uses a robotic arm to pick up the wafer. However, the structure of the additional robotic arm increases the product size, is not conducive to space layout, and increases the equipment cost.

[0003] Based on this, a pre-alignment device and an alignment method are urgently needed to solve the above-mentioned problems. Summary of the invention

[0004] Based on the above, the purpose of the present invention is to provide a pre-alignment instrument and alignment method, wherein there is no connecting rod between the alignment device and the detection device, and there is no obstruction in the four horizontal directions; the pre-alignment of the wafer can be achieved by using an adjustment component, without the need for a robotic arm, thereby reducing the product size, facilitating spatial layout, and reducing equipment costs.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] In one aspect, a pre-alignment instrument is provided, comprising an alignment device and a detection device, wherein the alignment device comprises:

[0007] A carrier, wherein the carrier is provided with an elongated hole extending along a first direction;

[0008] A support assembly, wherein the support assembly includes a first support column and a support component, wherein the support component includes at least two second support columns, wherein the second support columns are distributed on both sides of the elongated hole along a second direction, and the first support column and at least two of the second support columns are used to support the wafer;

[0009] An adjustment component, comprising a tray and a driving component, wherein the driving component is located below the carrier, the driving component is provided with an output shaft, the output shaft is passed through the long hole and connected to the tray, the tray is used to carry and adsorb the wafer, and the driving component is used to drive the tray to move;

[0010] The detection device is arranged above the alignment device, and includes a shell and a camera. The camera is installed in the shell. The bottom wall of the shell is provided with an avoidance hole. The camera can illuminate the edge of the wafer close to the first supporting column through the avoidance hole.

[0011] As a preferred technical solution of a pre-alignment instrument, the support components are at least two groups, and each group of the support components includes two second support columns; the support components are arranged at intervals along the first direction, and the distance between the two second support columns in the support components gradually increases along the direction away from the first support column.

[0012] As a preferred technical solution for a pre-alignment instrument, the two second support columns in the support component are arranged on the upper surface of the carrier and are symmetrically arranged with the center line of the long hole; the first support column is arranged near one end of the long hole, and the two second support columns in the same group are arranged in an isosceles triangle with the first support column.

[0013] As a preferred technical solution of a pre-alignment instrument, the supporting end surfaces of the first supporting column and the second supporting column are on the same horizontal plane.

[0014] As a preferred technical solution of a pre-alignment instrument, a height adjustment device is provided below the first support column and / or the second support column, and the height adjustment device is suitable for adjusting the height of the support end faces of the first support column and the preset second support column to the same horizontal height.

[0015] As a preferred technical solution of a pre-aligner, the support end surfaces of the two second support columns in each group of the support components are located on the same horizontal plane, and the height of the second support column gradually increases in a direction away from the first support column;

[0016] The support assembly also includes a second lifting drive member, which is connected to the first support column and drives the first support column to be lifted and lowered to be flush with the support end surface of the second support column in one group of the support components to horizontally support one of the wafers.

[0017] As a preferred technical solution for a pre-alignment instrument, the driving component includes a first horizontal driving member, a first lifting driving member and a first rotating driving member, the first horizontal driving member is drivingly connected to the first lifting driving member, the first horizontal driving member is used to drive the first lifting driving member to move along a first direction; the first lifting driving member is drivingly connected to the first rotating driving member, the first lifting driving member is used to drive the first rotating driving member to rise and fall, the first rotating driving member is provided with the output shaft, the output shaft is passed through the long hole and connected to the tray, the first rotating driving member is used to drive the tray to rotate.

[0018] As a preferred technical solution of a pre-alignment instrument, the detection device also includes a cache component, which is installed at the bottom of the shell, and the cache component is spaced apart from the camera along a first direction. The cache component includes a non-contact suction cup, and the non-contact suction cup is used to adsorb the wafer.

[0019] As a preferred technical solution of the pre-aligner, the cache assembly further includes a third lifting drive member, a mounting base plate, a mounting plate and a plurality of positioning pins, the third lifting drive member is connected to the housing and drivingly connected to the mounting base plate, the third lifting drive member is used to drive the mounting base plate to lift, and the mounting plate and the non-contact suction cup are both mounted on the mounting base plate;

[0020] A plurality of the positioning pins are arranged on the mounting plate, a plurality of the positioning pins are arranged around the non-contact suction cup, and the wafer can be embedded between the plurality of the positioning pins.

[0021] As a preferred technical solution of a pre-aligner, the non-contact chuck is a Bernoulli chuck or an electrostatic chuck.

[0022] As a preferred technical solution of a pre-alignment instrument, a tapered portion is provided at one end of the positioning pin away from the mounting plate, a plurality of the positioning pins form a first circle on the side wall close to the non-contact suction cup, the centers of the tapered portions of the plurality of positioning pins form a second circle, and the diameter of the wafer is between the diameter of the first circle and the diameter of the second circle.

[0023] On the other hand, an alignment method is provided, which is applied to the pre-alignment apparatus described in any one of the above items, and the alignment method comprises the following steps:

[0024] S1, placing the wafer horizontally on a first supporting column and two second supporting columns;

[0025] S2, the driving component drives the tray to move to the bottom of the wafer, lifts the wafer and drives the wafer to rotate by a preset angle. When the wafer rotates, the camera obtains the contour information of the edge of the wafer and calculates the center coordinates of the wafer, and calculates the eccentricity of the wafer according to the center coordinates;

[0026] S3, the driving component drives the wafer to rotate according to the eccentricity data calculated in step S2, so that the line connecting the center of the wafer and the center of the tray is located in the first direction;

[0027] S4, after the driving component drives the tray to descend to a level lower than the level where the first supporting columns are located, the wafer is supported by the first supporting columns and one group of the second supporting columns, and then the tray moves along the first direction to directly below the wafer, and the center of the wafer and the center of the tray are located on the same vertical line;

[0028] S5. The driving component drives the tray to move upward and lift the wafer to complete the center calibration of the wafer.

[0029] As a preferred technical solution of an alignment method, when a notch or a flat edge is provided at the edge of the wafer, the step S2 further comprises the camera acquiring the coordinates of the notch or the flat edge;

[0030] The alignment method further comprises:

[0031] S6. The driving component drives the tray to rotate so that a line connecting the center of the notch or the center of the flat edge and the center of the tray is located in the first direction.

[0032] The beneficial effects of the present invention are:

[0033] The present invention provides a pre-aligner. When working, the edge of a wafer is overlapped on a first supporting column and two second supporting columns; a driving component drives a tray to move to the bottom of the wafer, holds the wafer and drives the wafer to rotate a preset angle. When the wafer rotates, a camera obtains the contour information of the wafer and calculates the center coordinates of the wafer, and calculates the center offset according to the center coordinates; the driving component drives the wafer so that the center of the wafer is located on one side of the center of the tray along a first direction; the driving component drives the tray to descend and move along the first direction so that the center of the tray coincides with the center of the wafer; the driving component drives the tray to hold the wafer to complete the calibration of the wafer.

[0034] The present invention separates the alignment device and the detection device into two relatively independent modules. The alignment device and the detection device are installed independently, there is no connecting rod between the alignment device and the detection device, and there is no obstruction in the four horizontal directions; furthermore, after the center deviation of the wafer is identified, the adjustment component can be used to achieve pre-alignment of the wafer, without the need for a mechanical arm, reducing the product size, facilitating space layout, and reducing equipment costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0036] Figure 1 It is a structural schematic diagram of a pre-alignment instrument provided in a specific embodiment of the present invention;

[0037] Figure 2 is a top view of an alignment device provided in a specific embodiment of the present invention;

[0038] Figure 3 is a cross-sectional view of a detection device provided in a specific embodiment of the present invention;

[0039] Figure 4 is a bottom view of a detection device provided in a specific embodiment of the present invention;

[0040] Figure 5 is one of the cross-sectional views of the alignment device provided in the specific embodiment of the present invention;

[0041] Figure 6 is a second cross-sectional view of the alignment device provided in a specific embodiment of the present invention;

[0042] Figure 7 It is a partial structural schematic diagram of a detection device provided in a specific embodiment of the present invention;

[0043] Figure 8 It is a flow chart of the alignment method provided by a specific embodiment of the present invention.

[0044] The following are marked in the figure:

[0045] 1. Alignment device; 11. Housing; 111. Carrier; 1111. Long strip hole; 12. Support assembly; 121. First support column; 122. Support component; 1221. Second support column; 123. Second lifting drive member; 13. Adjustment assembly; 131. Tray; 132. Drive member; 1321. First horizontal drive member; 1322. First lifting drive member; 1323. First rotation drive member; 13231. Output shaft;

[0046] 2. Detection device; 21. Shell; 211. Avoidance hole; 22. Camera; 23. Cache assembly; 231. Non-contact suction cup; 232. Third lifting drive member; 233. Mounting base plate; 234. Mounting plate; 235. Positioning pin; 2351. Conical portion. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0048] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0051] like Figure 1-Figure 4As shown, this embodiment provides a pre-aligner, which includes an alignment device 1 and a detection device 2 . The alignment device 1 includes a stage 111 , a supporting component 12 and an adjusting component 13 . The carrier 111 is provided with an elongated hole 1111 extending along a first direction; the support assembly 12 includes a first support column 121 and a support part 122, the support part 122 includes at least two second support columns 1221, and the at least two second support columns 1221 cooperate with one first support column 121 to realize three-point support, which not only has good support stability, but also facilitates adjustment of the support horizontality and can effectively reduce the wear of the support column on the support end surface of the wafer; the second support columns 1221 are distributed on both sides of the elongated hole 1111 along the second direction and are fixedly arranged on the upper surface of the carrier 111. The second direction of this embodiment is arranged vertically with the first direction on the horizontal plane, and the two second support columns 1221 are symmetrically arranged on both sides of the elongated hole 1111. The first support column 121 and the two second support columns 1221 are used to support the position close to the edge of the wafer, so as to reserve enough space between the support columns for the tray 131 to move; the adjustment assembly 1 3 comprises a tray 131 and a driving component 132, the driving component 132 is located below the carrier 111, the driving component 132 is provided with an output shaft 13231, the output shaft 13231 is penetrated through the long hole 1111 and connected to the tray 131, the tray 131 is used to carry and adsorb the wafer, and the driving component 132 is used to drive the tray 131 to rise and fall, rotate and move along the first direction; the detection device 2 is arranged above the alignment device 1, the detection device 2 comprises a shell 21 and a camera 22, the camera 22 of this embodiment is preferably a linear matrix camera, the side of the first support column 121 away from the long hole 1111 is basically located at the center of the scanning area of ​​the linear matrix camera, when wafers of different sizes are placed on the support assembly 12, the edge thereof located on the side of the first support column 121 is basically located at the center of the scanning area, so that when the wafer rotates, the contour of its edge can pass through the scanning area, and then the edge information of the wafer is collected by the linear camera 22. The camera 22 is installed in the housing 21. The bottom wall of the housing 21 is provided with an avoidance hole 211. The camera 22 can illuminate the edge of the wafer on the first support column 121 through the avoidance hole 211. In this embodiment, the tray 131 can adsorb the wafer when holding the wafer. The adsorption method is vacuum adsorption. Several vacuum nozzles or vacuum grooves can be provided on the support surface of the tray 131 for vacuum adsorption to improve the stability of the wafer. Figure 1 , the first direction is X, the second direction is Y, and the first direction is perpendicular to the second direction.

[0052] During operation, the wafer is placed on the first supporting column 121 and the second supporting column 1221. Figure 2 As shown, in this embodiment, one first support column 121 is provided, which is located outside the first elongated hole 1111 and is arranged close to the end of the elongated hole 1111. Figure 2 On the horizontal projection plane shown, the line connecting the axis of the first support column 121 and the axis of the tray 131 is in the first direction (X direction), and the second support columns 1221 are symmetrically arranged on both sides of the long hole 1111 along the second direction (Y direction); the driving component 132 drives the tray 131 to move to the bottom of the wafer, holds the wafer and drives the wafer to rotate a preset angle. In this embodiment, the preset angle is preferably one circle. When the wafer rotates, the edges of the wafer pass through the scanning area of ​​the camera 22 in sequence according to the rotation direction. Figure 2 The left side of the long hole 1111 shown in the figure obtains the contour information of the wafer and calculates the center coordinates of the wafer, and calculates the center offset according to the center coordinates; the driving component 132 drives the wafer so that the center of the wafer is located on one side of the center of the tray 131 along the first direction. At this time, the offset of the center of the wafer in the Y direction is adjusted to 0, that is, the eccentricity correction in the Y direction is completed; then the driving component 132 drives the tray 131 to descend to a height lower than the supporting end face of the supporting column. At this time, the wafer is separated from the tray 131 because it is supported by the first supporting column 121 and the second supporting column 1221. When the tray 131 moves downward and is completely separated from the wafer , the driving component 132 drives the tray 131 to move along the first direction until the center of the tray 131 is directly below the center of the wafer, that is, at this time, the center of the tray 131 coincides with the horizontal projection of the center of the wafer, and the X-axis offset correction of the wafer is completed; then the driving component 132 drives the tray 131 to move upward, and lifts the wafer placed on the first support column 121 and the second support column 1221 upward. After the wafer is separated from the support columns, the tray 131 starts vacuum adsorption to fix the wafer, and the center calibration of the wafer is completed, that is, at this time, the center of the wafer lifted on the tray 131 coincides with the center of the tray 131 itself. In order to facilitate photolithography alignment, the edges of existing wafers are generally provided with notch marks and flat edge marks. In the above process, after the wafer rotates one circle, the camera 22 collects the position information of the edge of the wafer, not only calculates the eccentricity of the center of the wafer, but also confirms the position coordinate information of the notch or flat edge mark at the edge of the wafer. When the center of the wafer is corrected to coincide with the center of the tray 131, the position information of the notch or flat edge on the edge of the wafer has been confirmed. By rotating a certain angle in the forward or reverse direction, the center point of the notch or flat edge position of the wafer can be rotated to the preset position to complete the edge finding action. Preferably, the line connecting the preset position of the notch or flat edge and the center of the tray 131 is in the first direction.

[0053] This embodiment splits the alignment device 1 and the detection device 2 into two relatively independent modules. The alignment device 1 and the detection device 2 are installed independently, there is no connecting rod between the alignment device 1 and the detection device 2, and the area between the two is not blocked in the circumferential direction; furthermore, after identifying the center deviation of the wafer, the adjustment component 13 can be used to achieve pre-alignment of the wafer, without the need to use a mechanical arm for position compensation, reducing the product size, facilitating space layout, and reducing equipment costs; finally, the wafer is supported by the first support column 121 and the two second support columns 1221, and the top surfaces of the first support column 121 and the two second support columns 1221 are flush, ensuring that the wafer remains flat during the adsorption process of the tray 131, and can avoid bending or cracking of the wafer due to uneven force, and the first support column 121 and the two second support columns 1221 support have good adsorption reliability and versatility, can be applied to the support adsorption of wafers of different sizes, high flexibility, simple maintenance, and low cost.

[0054] It should be noted that when the wafer rotates, the camera 22 obtains the contour information of the wafer and calculates the center coordinates of the wafer. This is a prior art, and its working principle and calculation method will not be described in detail here.

[0055] Preferably, if Figure 1 and Figure 2 As shown, the support components 122 are at least two groups, and seven groups are provided in this embodiment. The two second support columns 1221 in each group of support components 122 are symmetrically arranged relative to the long strip hole 1111, and each group of support components 122 includes two second support columns 1221; each group of support components 122 is arranged at intervals along the first direction, and the spacing between the two second support columns 1221 in the support components 122 gradually increases in the direction away from the first support column 121 to adapt to the wafer with increased size. By providing multiple groups of support components 122, it is convenient for the support components 122 to cooperate with the first support column 121 to support wafers of different models. In other embodiments, each group of support components 122 may also include more than three second support columns 1221, and may even be arranged to provide more than two forked support points on the upper end of a second support column 1221 for support. The specific support form is not limited, as long as it can cooperate with the first support column 121 to achieve multi-point support of the wafer.

[0056] In the prior art, wafers of different sizes are in a concentric state during pre-alignment. Therefore, the position that the camera needs to scan during pre-alignment is inconsistent. In order to adapt to each size of wafer, a camera is designed separately. The advantage of this is that the position of the camera is fixed and easy to use. However, due to the use of multiple cameras, this solution greatly increases the cost and has a great impact on the space. Another solution is to add a lateral axis to the camera, and move the camera position so that the camera of the pre-aligner can just scan the edge of wafers of different sizes. However, this solution has a high requirement for load and motion accuracy due to the addition of an additional motion axis to drive the camera to move, and the motion axis has high requirements for load and motion accuracy, and according to the different needs of compatible wafer sizes, when compatible with 2-12 inch wafers, the stroke of the motion axis can be close to 150mm. Therefore, the impact on the overall space and price is also large. And when the camera moves, it will not only affect its optimal focal plane (affecting the clarity of image acquisition), but also when it moves frequently, the reference coordinates of the camera will change frequently, which will increase the amount of calculation and cumulative error, and thus have a great impact on the detection accuracy.

[0057] To solve the above problems, Figure 2 and Figure 5 As shown, the present application sets a base point on the side of the first support column 121 away from the long hole 1111 (the base point is preset by the system, and the pre-alignment mark is not specially set in the pre-alignment instrument), and wafers of different sizes and models are placed starting from the base point, see Figure 2As the size of the wafer increases, the right edge of the wafer gradually extends to the right. When the height of each group of second support pillars 1221 is consistent with that of the first support pillars 121, the second support pillars 1221 under the horizontal projection of the wafer of the corresponding size will all play a supporting role. The advantage of this method is that the bottom surface of the wafer can be supported at multiple points. The disadvantage is that when the multiple second support pillars 1221 are adjusted to the same horizontal height, the assembly process requirements are high, and once the wafer is not flat enough, it will also affect the stability of the support. To this end, in other embodiments, the support end surfaces of the two second support columns 1221 in each group of support parts 122 are located on the same horizontal plane, and the heights of the second support columns 1221 in adjacent support parts 122 gradually increase in the direction away from the first support column 121; for example, the increased height can be around 1-2 mm, and the height difference can also be other values; the support assembly 12 also includes a second lifting drive member 123, which is connected to the first support column 121 and drives the first support column 121 to rise and fall until it is flush with the support end surface of the second support column 1221 in one of the groups of support parts 122, so as to horizontally support a wafer. In this embodiment, different groups of support components 122 correspond to different types of wafers. Therefore, when supporting different types of wafers, the second lifting drive 123 drives the first support column 121 to rise and fall, so that the first support column 121 and the second support column 1221 of the corresponding support component 122 have the same height, ensuring that the edges of wafers of different types are supported by one first support column 121 and two second support columns 1221, all of which are three-point supported. For the horizontal adjustment process, due to the small number of support points, it is easier to adjust the level, and due to the three-point support, the resistance area on the back of the wafer is reduced, thereby reducing the wear on the back of the wafer. Furthermore, in this embodiment, when wafers of different types are placed on the first support column 121, the edge of the wafer close to the first support column 121 is located at the base point position and is located within the detection range of the camera 22. When the wafer rotates, the edge of the wafer below the camera 22 is always within the detection range of the camera 22, so that the pre-alignment requirements of wafers of different specifications can be met when only one camera 22 is used.

[0058] Preferably, the first support column 121 and the second support column 1221 can absorb the wafer to improve the stability of the wafer. The second support columns 1221 of different groups of support components 122 can perform independent vacuum switch actions to achieve the purpose of absorbing wafers of different sizes.

[0059] like Figure 2As shown, this embodiment includes a total of 7 groups of support components 122. Along the direction away from the first support column 121, the first group of support components 122 cooperate with the first support column 121 to support 2-inch wafers; the second group of support components 122 cooperate with the first support column 121 to support 3-inch wafers; the third group of support components 122 cooperate with the first support column 121 to support 4-inch wafers; the fourth group of support components 122 cooperate with the first support column 121 to support 5-inch wafers; the fifth group of support components 122 cooperate with the first support column 121 to support 6-inch wafers; the sixth group of support components 122 cooperate with the first support column 121 to support 8-inch wafers; the seventh group of support components 122 cooperate with the first support column 121 to support 12-inch wafers. Figure 2 The 7 circles shown in the figure represent the outlines of 2-inch, 3-inch, 4-inch, 5-inch, 6-inch, 8-inch, and 12-inch wafers respectively (the above sizes are also the most common standard wafer sizes at present). Wafers of different models are not placed on the pre-aligner of the present invention for pre-alignment at the same time. Instead, when pre-aligning, each batch of pre-alignment work is only for one type of wafer. For example, when pre-aligning 2-inch wafers, only the Figure 2 When the 12-inch wafer is pre-aligned, the 12-inch wafer is mainly supported by the leftmost first supporting column 121 and the rightmost two second supporting columns 1221.

[0060] When supporting wafers of different sizes, it is preferred that the two second support columns 1221 closest to the wafer edge under the horizontal projection of the wafer cooperate with the first support column 121 for support. Of course, if the heights of the second support columns 1221 on the carrier 111 are all set to be consistent, the support end surfaces of the first support column 121 and the second support column 1221 are on the same horizontal plane, then all the second support columns 1221 and the first support column 121 under the horizontal projection of the wafer of the corresponding size can support the wafer. Taking a 12-inch wafer as an example, at this time Figure 2 The first support columns 121 and the second support columns 1221 shown are both located below the horizontal projection of the 12-inch wafer, and together support the 12-inch wafer. Figure 6 As shown, the second support columns 1221 of the plurality of support components 122 have the same height, which can simplify the product structure. During assembly, the horizontal heights of the second support columns 1221 need to be adjusted to be consistent, and each second support column 1221 is fixed to the upper surface of the carrier 111.

[0061] In other embodiments, a height adjustment device is provided below the first support column 121 and / or the second support column 1221, and the height adjustment device is suitable for adjusting the height of the support end surface of the first support column 121 and the preset second support column 1221 to the same horizontal height. That is, the first support column 121 and the second support column 1221 of the present application can both be adjusted in height by the height adjustment device, or the height of one of them can be fixed, and the height of the other can be adjusted by the height adjustment device. The above embodiment introduces the height adjustment of the first support column 121. In other embodiments, the first support column 121 can also be fixed, and the height adjustment device can be provided below the second support column 1221. A height adjustment device can be provided below each second support column 1221, or all the second support columns 1221 with height differences can be adjusted in height as a whole. The present application does not impose any restrictions on this, as long as it can facilitate the adjustment of the support effect of the support column on the wafer; and the structure of the height adjustment device is not limited, as long as it is a mechanism or device that is easy to control and can be driven up and down.

[0062] Further, the driving component 132 includes a first horizontal driving member 1321, a first lifting driving member 1322 and a first rotating driving member 1323. The first horizontal driving member 1321 is connected to the first lifting driving member 1322, and the first horizontal driving member 1321 is used to drive the first lifting driving member 1322 to move in the first direction; the first lifting driving member 1322 is connected to the first rotating driving member 1323, and the first lifting driving member 1322 is used to drive the first rotating driving member 1323 to move up and down. The first rotating driving member 1323 is provided with an output shaft 13231, and the output shaft 13231 is passed through the long hole 1111 and connected to the tray 131, and the first rotating driving member 1323 is used to drive the tray 131 to rotate. When the first horizontal driving member 1321 drives the first lifting driving member 1322 to move in the first direction, the tray 131 is driven to move in the first direction. When the first lifting driving member 1322 drives the first rotating driving member 1323 to move up and down, the tray 131 is driven to move up and down. In this embodiment, the first horizontal driving member 1321 and the first lifting driving member 1322 both use linear driving modules, and the first rotating driving member 1323 uses a rotating motor. In this embodiment, the driving member 132 is disposed in the housing 11, and a platform 111 is disposed on the top of the housing 11.

[0063] Preferably, if Figure 3 , Figure 4 and Figure 7As shown, the detection device 2 also includes a cache component 23, which is installed at the bottom of the housing 21. The cache component 23 and the camera 22 are spaced apart along the first direction. The cache component 23 includes a non-contact suction cup 231, which is used to adsorb wafers. When it is necessary to cache the wafer, the non-contact suction cup 231 adsorbs the top surface of the wafer to achieve wafer caching, and the non-contact suction cup 231 has no contact with the top surface of the wafer to prevent contamination and damage to the glue-coated surface of the wafer. Among them, the non-contact suction cup 231 is a Bernoulli suction cup or an electrostatic suction cup. In this embodiment, the non-contact suction cup 231 is a Bernoulli suction cup. A cache station is added by the cache component 23 to temporarily store or transport wafers that have been completed by lithography.

[0064] Further preferably, the cache assembly 23 also includes a third lifting drive member 232, a mounting base plate 233, a mounting plate 234 and a plurality of positioning pins 235. The third lifting drive member 232 is connected to the shell 21 and is driven to be connected to the mounting base plate 233. The third lifting drive member 232 is used to drive the mounting base plate 233 to rise and fall. The mounting plate 234 and the non-contact suction cup 231 are both installed on the mounting base plate 233; a plurality of positioning pins 235 are arranged on the mounting plate 234, and a plurality of positioning pins 235 are arranged around the non-contact suction cup 231, and the wafer can be embedded between the plurality of positioning pins 235.

[0065] The third lifting drive 232 drives the mounting base plate 233 to move up and down, which can drive the mounting plate 234 and the non-contact suction cup 231 to move up and down together. When the wafer needs to be adsorbed, the fork arm transports the wafer to the bottom of the Bernoulli suction cup, and the third lifting drive 232 pushes the Bernoulli suction cup downward to a preset distance. At this time, the gap between the upper surface of the wafer and the Bernoulli suction cup is within the adsorption range of the suction cup. The Bernoulli suction cup turns on positive pressure, and the wafer is adsorbed from above by the Bernoulli principle. The wafer is embedded between multiple positioning pins 235, and the multiple positioning pins 235 limit the wafer from moving or flipping radially.

[0066] In this embodiment, the third lifting drive member 232 can be an electric cylinder, a pneumatic cylinder or an oil cylinder. In this embodiment, an electric cylinder is selected. The motor of the electric cylinder is fixed inside the shell 21 through a motor mounting bracket. The end of the output shaft 13231 of the electric cylinder is connected to the Bernoulli suction cup and is coaxially arranged. The Bernoulli suction cup is driven by the electric cylinder to complete the ejection or reset action.

[0067] Preferably, a conical portion 2351 is provided at one end of the positioning pin 235 away from the mounting plate 234, and the side walls of the plurality of positioning pins 235 close to the non-contact suction cup 231 form a first circle, and the centers of the conical portions 2351 of the plurality of positioning pins 235 form a second circle, and the diameter of the wafer is between the diameter of the first circle and the diameter of the second circle. After the non-contact suction cup 231 adsorbs the wafer, the edge of the wafer abuts against the conical portion 2351 of the positioning pin 235, thereby fixing the position of the wafer and preventing the wafer from sliding horizontally, and the friction between the wafer and the conical portion 2351 limits the rotation of the wafer. The number of positioning pins 235 is preferably 3, and of course four, five, six, etc. may also be used in other embodiments. No matter how many positioning pins 235 are provided, the conical portions 2351 of each positioning pin 235 have the same structure and are evenly spaced in the circumferential direction.

[0068] Further preferably, the mounting plate 234 is detachably connected to the mounting base plate 233, so that the mounting plate 234 can be replaced as needed. For wafers of different sizes, positioning pins 235 at different positions are required, so mounting plates 234 of different sizes are provided for replacement, and mounting plates 234 of the correct specifications are used.

[0069] like Figure 8 As shown, this embodiment also provides an alignment method, which is applied to the above-mentioned pre-alignment instrument, and the alignment method includes the following steps:

[0070] S1, placing the wafer horizontally on the first support column 121 and the two second support columns 1221; wherein the edge of the wafer located on the first support column 121 is within the detection range of the camera 22;

[0071] S2, the driving component 132 drives the tray 131 to move to the bottom of the wafer, lifts the wafer and drives the wafer to rotate by a preset angle. When the wafer rotates, the camera 22 obtains the contour information of the edge of the wafer and calculates the coordinates of the center of the wafer, and calculates the eccentricity of the wafer according to the coordinates of the center of the wafer; wherein, the position of the tray 131 lifting the wafer is approximately located at the center of the wafer, so that when the wafer rotates by a preset angle, the edge of the wafer located below the camera 22 is always within the detection range of the camera 22;

[0072] S3, the driving component 132 drives the wafer to rotate according to the eccentricity data calculated in step S2, so that the line connecting the center of the wafer and the center of the tray 131 is located in the first direction; ensuring that the center of the wafer is located on the moving path of the tray 131 along the first direction;

[0073] S4, after the driving component 132 drives the tray 131 to descend to a level lower than the first support column 121, the wafer is supported by the first support column 121 and one group of the second support columns 1221, and then the tray 131 moves along the first direction to directly below the wafer, and the center of the wafer and the center of the tray 131 are located on the same vertical line to compensate for the eccentricity of the center;

[0074] S5. The driving component 132 drives the tray 131 to move upward and lift the wafer to complete the center calibration of the wafer.

[0075] Furthermore, when the edge of the wafer is provided with a notch or a flat edge, step S2 also includes the camera 22 acquiring the coordinates of the notch or the flat edge; the alignment method also includes: S6, the driving component 132 drives the tray 131 to rotate so that the line connecting the center of the notch or the center of the flat edge and the center of the tray 131 is located in the first direction to complete the orientation.

[0076] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A pre-alignment instrument, characterized in that: The invention comprises an alignment device (1) and a detection device (2), wherein the alignment device (1) comprises: A carrier (111), wherein the carrier (111) is provided with an elongated hole (1111) extending along a first direction; A support assembly (12), the support assembly (12) comprising a first support column (121) and a support component (122), the support component (122) comprising at least two second support columns (1221), the second support columns (1221) being distributed on both sides of the long hole (1111) along a second direction, the first support column (121) and the at least two second support columns (1221) being used to support a wafer; An adjustment component (13), comprising a tray (131) and a driving component (132), wherein the driving component (132) is located below the carrier (111), and the driving component (132) is provided with an output shaft (13231), wherein the output shaft (13231) passes through the long hole (1111) and is connected to the tray (131), wherein the tray (131) is used to carry and adsorb wafers, and the driving component (132) is used to drive the tray (131) to move; The detection device (2) is arranged above the alignment device (1), and comprises a shell (21) and a camera (22). The camera (22) is installed in the shell (21), and a avoidance hole (211) is provided on the bottom wall of the shell (21). The camera (22) can illuminate the edge of the wafer on the side close to the first support column (121) through the avoidance hole (211).

2. The pre-alignment device according to claim 1, characterized in that: The support components (122) are at least two groups, and each group of the support components (122) comprises two second support columns (1221); the support components (122) are arranged at intervals along the first direction, and the distance between the two second support columns (1221) in the support components (122) gradually increases along the direction away from the first support column (121).

3. The pre-alignment device according to claim 2, characterized in that: The two second support columns (1221) in the support component (122) are arranged on the upper surface of the carrier (111) and are symmetrically arranged with respect to the midline of the elongated hole (1111); the first support column (121) is arranged close to one end of the elongated hole (111), and the two second support columns (1221) in the same group are arranged in an isosceles triangle with the first support column (121).

4. The pre-alignment device according to claim 3, characterized in that: The supporting end surfaces of the first supporting column (121) and the second supporting column (1221) are on the same horizontal plane.

5. The pre-alignment device according to claim 3, characterized in that: A height adjustment device is provided below the first support column (121) and / or the second support column (1221), and the height adjustment device is used to adjust the heights of the support end surfaces of the first support column (121) and the preset second support column (1221) to the same horizontal height.

6. The pre-alignment device according to claim 3, characterized in that: The supporting end surfaces of the two second supporting columns (1221) in each group of the supporting components (122) are located on the same horizontal plane, and the height of the second supporting columns (1221) gradually increases in a direction away from the first supporting columns (121); The support assembly (12) also includes a second lifting drive member (123), which is connected to the first support column (121) and drives the first support column (121) to be lifted and lowered until it is flush with the support end surface of the second support column (1221) in one group of the support components (122) to horizontally support one of the wafers.

7. The pre-alignment device according to any one of claims 4 to 6, characterized in that: The driving component (132) includes a first horizontal driving member (1321), a first lifting driving member (1322) and a first rotating driving member (1323). The first horizontal driving member (1321) is drivingly connected to the first lifting driving member (1322). The first horizontal driving member (1321) is used to drive the first lifting driving member (1322) to move along the first direction; the first lifting driving member (1322) is drivingly connected to the first rotating driving member (1323). The first lifting driving member (1322) is used to drive the first rotating driving member (1323) to rise and fall. The first rotating driving member (1323) is provided with the output shaft (13231). The output shaft (13231) is passed through the long hole (1111) and connected to the tray (131). The first rotating driving member (1323) is used to drive the tray (131) to rotate.

8. The pre-alignment device according to any one of claims 1 to 6, characterized in that: The detection device (2) further comprises a cache component (23), wherein the cache component (23) is mounted on the bottom of the housing (21), the cache component (23) and the camera (22) are spaced apart along a first direction, and the cache component (23) comprises a non-contact suction cup (231), and the non-contact suction cup (231) is used to absorb the wafer.

9. The pre-alignment apparatus according to claim 8, characterized in that: The cache assembly (23) further comprises a third lifting drive member (232), a mounting base plate (233), a mounting plate (234) and a plurality of positioning pins (235), wherein the third lifting drive member (232) is connected to the housing (21) and is drivingly connected to the mounting base plate (233), and the third lifting drive member (232) is used to drive the mounting base plate (233) to rise and fall, and the mounting plate (234) and the non-contact suction cup (231) are both mounted on the mounting base plate (233); The plurality of positioning pins (235) are arranged on the mounting plate (234), the plurality of positioning pins (235) are arranged around the non-contact suction cup (231), and the wafer can be embedded between the plurality of positioning pins (235).

10. The pre-alignment apparatus according to claim 9, characterized in that: The non-contact suction cup (231) is a Bernoulli suction cup or an electrostatic suction cup.

11. The pre-alignment apparatus according to claim 9, characterized in that: A conical portion (2351) is provided at one end of the positioning pin (235) away from the mounting plate (234), and the side wall of the plurality of positioning pins (235) close to the non-contact suction cup (231) forms a first circle, and the centers of the conical portions (2351) of the plurality of positioning pins (235) form a second circle, and the diameter of the wafer is between the diameter of the first circle and the diameter of the second circle.

12. An alignment method, characterized in that: Applied to the pre-alignment apparatus as claimed in any one of claims 1 to 11, the alignment method comprises the following steps; S1, placing a wafer horizontally on a first supporting column (121) and two second supporting columns (1221); S2, the driving component (132) drives the tray (131) to move to the bottom of the wafer, lifts the wafer and drives the wafer to rotate by a preset angle, when the wafer rotates, the camera (22) obtains the contour information of the edge of the wafer and calculates the center coordinates of the wafer, and calculates the eccentricity of the wafer according to the center coordinates; S3, the driving component (132) drives the wafer to rotate according to the eccentricity data calculated in step S2, so that a line connecting the center of the wafer and the center of the tray (131) is located in a first direction; S4, after the driving component (132) drives the tray (131) to descend to a level lower than the level at which the first supporting column (121) is located, the wafer is supported by the first supporting column (121) and one group of the second supporting columns (1221), and then the tray (131) moves along the first direction to directly below the wafer, and the center of the wafer and the center of the tray (131) are located on the same vertical line; S5. The driving component (132) drives the tray (131) to move upward and lift the wafer, thereby completing the center calibration of the wafer.

13. The alignment method according to claim 12, characterized in that: When the edge of the wafer is provided with a notch or a flat edge, the step S2 further comprises the camera (22) acquiring the coordinates of the notch or the flat edge; The alignment method further comprises: S6. The driving component (132) drives the tray (131) to rotate so that a line connecting the center of the notch or the center of the flat edge and the center of the tray (131) is located in the first direction.

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