阅读说明：本技术 一种用于晶圆检测的补正装置 (A revise device for wafer detects ) 是由 胡俊林 赵峰 孙会民 蔡章华 于 2021-10-25 设计创作，主要内容包括：公开了一种用于晶圆检测的补正装置,包括安装底板、多个XYθ轴导向模组、驱动装置和载台组件,载台组件可旋转地设置于安装底板上,多个XYθ轴导向模组设置于安装底板与载台组件之间并均布于载台组件的旋转轴所处的圆上,XYθ轴导向模组自下而上包括导向模组底板、X轴导向模块、Y轴导向模块和旋转模块,导向模组底板与安装底板固定,旋转模块与载台组件固定连接,驱动装置与其中一个XYθ轴导向模组的X轴导向模块连接以推动载台组件旋转。该装置可以实现高刚性角度补正和零抖动检测。(The utility model discloses a revise device for wafer detection, including the mounting plate, a plurality of XY theta axle guide module, drive arrangement and microscope carrier subassembly, the microscope carrier subassembly rotatably sets up on the mounting plate, a plurality of XY theta axle guide module set up between mounting plate and microscope carrier subassembly and the equipartition is on the circle that the rotation axis of microscope carrier subassembly was located, XY theta axle guide module includes direction module bottom plate from bottom to top, X axle guide module, Y axle guide module and rotation module, direction module bottom plate is fixed with the mounting plate, rotation module and microscope carrier subassembly fixed connection, drive arrangement is connected in order to promote the microscope carrier subassembly to rotate with the X axle guide module of one of them XY theta axle guide module. The device can realize high rigidity angle correction and zero jitter detection.)

1. A correction device for wafer detection is characterized by comprising an installation bottom plate, a plurality of XY theta axis guide modules, a driving device and a platform assembly, wherein the platform assembly is rotatably arranged on the installation bottom plate, the XY theta axis guide modules are arranged between the installation bottom plate and the platform assembly and are uniformly distributed on a circle where a rotating shaft of the platform assembly is located, the XY theta axis guide modules comprise a guide module bottom plate, an X axis guide module, a Y axis guide module and a rotating module from bottom to top, the guide module bottom plate is fixed with the installation bottom plate, the rotating module is fixedly connected with the platform assembly, and the driving device is connected with the X axis guide module of one XY theta axis guide module to push the platform assembly to rotate.

2. The correction device for wafer detection as claimed in claim 1, wherein the stage assembly is rotatably disposed on the mounting base plate via a rotation assembly, the rotation assembly includes a cross roller bearing and a rotation shaft, an outer ring of the cross roller bearing is fixed to the mounting base plate, and two ends of the rotation shaft are respectively connected to an inner ring of the cross roller bearing and a lower end surface of the stage assembly.

3. The correction device for wafer detection as claimed in claim 2, comprising 3 XY θ axis guiding modules, wherein the 3 XY θ axis guiding modules are distributed on the mounting base plate and located at the trisection point of the circle where the rotation axis of the stage assembly is located.

4. The correction device for wafer detection as claimed in claim 1, wherein a relationship between a relative movement amount δ X of the X-axis guide module and a rotation angle δ θ of the stage assembly is: δ X is Rcos (δ θ + θ) -R cos θ, where R is a radius of a circle where the XY θ axis guide module is located at the rotation axis of the stage assembly, and θ is an angle between the radius of the current position and the X axis.

5. The correction device for wafer inspection as claimed in claim 4, wherein the driving device includes a motor and a ball screw mechanism, the motor drives the ball screw mechanism, a screw nut of the ball screw mechanism is disposed on a connection seat, and the connection seat is fixedly connected to the X-axis guiding module.

6. The correction device for wafer detection as claimed in claim 2, wherein the stage assembly includes a rotation axis mounting plate rotatably disposed on the mounting base plate by a rotation assembly, a horizontal adjustment mechanism, and a vacuum suction platform disposed on the rotation axis mounting plate by a plurality of horizontal adjustment mechanisms.

7. The apparatus as claimed in claim 6, wherein the apparatus comprises at least 3 horizontal adjustment mechanisms uniformly disposed on a circle on which an axis of the spindle is located.

8. The apparatus as claimed in claim 1, wherein the guide module bottom plate has an X-axis guide, an X-axis guide rail is correspondingly disposed in the X-axis guide module, a Y-axis guide is further disposed on the X-axis guide module, and a Y-axis guide rail is correspondingly disposed in the Y-axis guide module.

9. The apparatus as claimed in claim 8, wherein the rotating module is a bearing, an inner ring of the bearing is fixedly connected to a lower end surface of the stage assembly, and an outer ring of the bearing is fixedly connected to an upper end surface of the Y-axis guiding module.

10. The correction device for wafer detection as claimed in claim 5, wherein a relative movement δ X of the X-axis guiding module is n × p, where n represents a rotation number of the lead screw and p represents a lead of the lead screw.

Technical Field

The present invention relates to the field of wafer inspection devices, and more particularly, to a correction device for wafer inspection.

Background

The wafer detection content includes detecting foreign matters, edge breakage, erosion and the like. In order to maximize the detection efficiency and accuracy, it is necessary to ensure that the chips on the wafer can be imaged at the center of the field of view of the microscope, i.e. the direction of the crystal grains needs to be consistent with the detection direction of the microscope. The direction of the wafer when being transferred to the detection platform cannot be consistent with the moving direction of the microscope, and in order to ensure high efficiency and accuracy of detection, the direction of the crystal grains of the wafer needs to be consistent with the moving direction of the microscope in the detection process. The current solutions are mainly the following two:

1. by adding a contraposition camera, the contraposition camera can shoot a plurality of pictures on the edge of the wafer, the angle error between the wafer and the detection direction is calculated by an algorithm, and the movement amounts of an X axis and a Y axis on the carrying platform are controlled, so that the crystal grains on the same line on the wafer can pass through the center of the field of view of the microscope.

2. On the basis of the above scheme, a direct-drive rotary servo motor is added below the detection platform, and after the angle error between the wafer and the detection direction is calculated, the servo motor is driven to rotate by a corresponding angle, so that the direction of the crystal grains is consistent with the moving direction of the microscope.

Although the above two-point solution can meet the detection requirement, the first solution is that two axes are driven to move simultaneously, and the smoothness of the multi-axis combined motion is not good as that of the single-axis motion, so that the quality of the photographed image is not as good as that of the single-axis driven photographing. The second scheme uses a direct-drive servo motor, and the motor can slightly shake all the time according to the characteristics of the servo motor, so that the image capturing quality is influenced.

Disclosure of Invention

In order to solve the technical problems that the smoothness of multi-axis combined motion is poor and the micro-jitter of a direct-drive servo motor influences the image capturing quality in the prior art, the invention provides a correction device for wafer detection, which is used for solving the problems in the prior art.

The invention provides a correcting device for wafer detection, which comprises an installation bottom plate, a plurality of XY theta axis guide modules, a driving device and a platform table component, wherein the platform table component is rotatably arranged on the installation bottom plate, the XY theta axis guide modules are arranged between the installation bottom plate and the platform table component and are uniformly distributed on a circle where a rotating shaft of the platform table component is located, the XY theta axis guide modules comprise a guide module bottom plate, an X axis guide module, a Y axis guide module and a rotating module from bottom to top, the guide module bottom plate is fixed with the installation bottom plate, the rotating module is fixedly connected with the platform table component, and the driving device is connected with the X axis guide module of one XY theta axis guide module to push the platform table component to rotate. The device pushes an X-axis guide module of an XY theta axis guide module to move through a driving device, and because the XY theta axis guide module has X, Y degrees of freedom in theta directions, the rest XY theta axis guide modules are limited by being fixed up and down, and the carrying platform assembly is driven to stably rotate for a certain angle in an ultrahigh reduction ratio within the range of the degrees of freedom.

Preferably, the carrier assembly is rotatably arranged on the mounting base plate through a rotating assembly, the rotating assembly comprises a crossed roller bearing and a rotating shaft, an outer ring of the crossed roller bearing is fixed with the mounting base plate, and two ends of the rotating shaft are respectively connected with an inner ring of the crossed roller bearing and the lower end face of the carrier assembly. With this arrangement, the stage assembly can be rotatably disposed on the mounting base plate and a space in which the XY θ axis guide module can be placed is formed therebetween.

Further preferably, the mounting base plate comprises 3 XY θ axis guide modules, and the 3 XY θ axis guide modules are distributed on the mounting base plate and located at the trisection point of the circle where the rotating shaft of the stage assembly is located. Rely on this setting can be more stable realization microscope carrier subassembly's rotation.

Preferably, a relationship between a relative movement amount δ X of the X-axis guide module and a rotation angle δ θ of the stage assembly is: δ X is R cos (δ θ + θ) -R cos θ, where R is the radius of the circle where the XY θ axis guide module is located at the rotation axis of the stage assembly, and θ is the angle between the radius of the current position and the X axis. By utilizing the formula, the relative movement amount of the X-axis guide module can be rapidly calculated and obtained, so that the feeding of the driving device can be conveniently controlled to realize accurate angular rotation.

Further preferably, the driving device comprises a motor and a ball screw mechanism, the motor drives the ball screw mechanism, a screw nut of the ball screw mechanism is arranged on the connecting seat, and the connecting seat is fixedly connected with the X-axis guiding module. The movement amount of the X-axis guide module can be conveniently controlled by utilizing the motor and the ball screw mechanism.

Further preferably, the stage assembly includes a rotating shaft mounting plate, a horizontal adjustment mechanism, and a vacuum adsorption platform, the rotating shaft mounting plate is rotatably disposed on the mounting base plate through the rotating assembly, and the vacuum adsorption platform is disposed on the rotating shaft mounting plate through the plurality of horizontal adjustment mechanisms. The levelness of the vacuum adsorption platform can be adjusted by means of the arrangement.

Further preferably, the device at least comprises 3 horizontal adjusting mechanisms which are uniformly distributed on a circle on which the axis of the rotating shaft is located. 3 points determine a plane, so that the levelness of the vacuum adsorption platform can be adjusted by only adjusting 3 horizontal adjusting mechanisms.

Preferably, the guide module bottom plate is provided with an X-axis guide part, an X-axis guide rail is correspondingly arranged in the X-axis guide module, a Y-axis guide part is further arranged on the X-axis guide module, and a Y-axis guide rail is correspondingly arranged in the Y-axis guide module. By virtue of this arrangement, two degrees of freedom in the X, Y direction of the guide module can be achieved.

Preferably, the rotating module is a bearing, an inner ring of the bearing is fixedly connected with the lower end face of the carrier assembly, and an outer ring of the bearing is fixedly connected with the upper end face of the Y-axis guide module. This arrangement allows the guide module to have one rotational degree of freedom in addition to X, Y two degrees of freedom.

Further preferably, the relative movement δ X of the X-axis guide module is equal to n × p, where n denotes the number of rotations of the lead screw, and p denotes the lead of the lead screw. The number of turns of the motor can be defined by the formula, so that the relative movement amount of the X-axis guide module can be controlled, and the rotation angle can be controlled.

The correction device for wafer detection drives the ball screw seat to move linearly by the stepping motor, realizes the complex motion of the cam mechanism by the X, Y and theta combined guide rail, and pushes the platform to rotate. Zero jitter in a static state can be realized due to the stepping motor, and the jitter problem of the direct-drive servo motor is perfectly solved. In addition, the ultrahigh speed reduction ratio can be realized by converting the linear motion into the rotary motion, the theta axis can be made very thin, and the X, Y combined guide rail is used for guiding, so that the ultrahigh rigidity is given to the platform. Therefore, the problems of angle correction and jitter are solved, and high-quality microscopic detection can be realized.

Drawings

The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and together with the description serve to explain the principles of the invention. Other embodiments and many of the intended advantages of embodiments will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.

FIG. 1 is an exploded view of a compensating device for wafer inspection according to one embodiment of the present invention;

FIG. 2 is a front view of a compensating device for wafer inspection according to an embodiment of the present invention;

FIG. 3 is an exploded view of an XY θ axis guide module in a correction device for wafer inspection according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a driving device in a correction device for wafer inspection according to an embodiment of the present invention.

The meaning of each number in the figure: the device comprises a 1-module mounting base plate, a 2-stepping motor, a 3-ball screw mechanism, a 31-stepping motor mounting base, a 32-coupler, a 33-coupler fixing base, a 34-screw, a 35-screw nut connecting base, a 4-XY theta axis guide module, a 41-guide module base, a 42-X axis guide part, a 43, an X axis guide module, a 42' -Y axis guide part, a 44-Y axis guide module, a 45-rotation module, a 5-crossed roller bearing, a 6-rotating shaft, a 7-rotating shaft mounting plate, an 8-carrying platform horizontal adjusting mechanism and a 9-vacuum adsorption platform.

Detailed Description

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "left," "right," "up," "down," etc., is used with reference to the orientation of the figures being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and logical changes may be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Fig. 1 shows an exploded view of a correction device for wafer inspection according to an embodiment of the present invention. As shown in fig. 1, the correction device for wafer inspection mainly includes a module mounting base plate 1, an XY θ axis guide module 4, a driving device, and a stage assembly, where the driving device includes a stepping motor 2 and a ball screw mechanism 3, and the stage assembly includes a rotation axis mounting plate 7, a stage horizontal adjustment mechanism 8, and a vacuum adsorption platform 9. A rotating shaft mounting plate 7 of the carrier assembly is rotatably arranged on the module mounting base plate 1 around a rotating shaft 6 through a crossed roller bearing 5 and the rotating shaft 6, an outer ring of the crossed ball bearing 5 is locked on the upper surface of the module mounting base plate 1, a lower end surface of the rotating shaft 6 is locked on an inner ring of the crossed ball bearing 5, a space is formed between the rotating shaft mounting plate 7 and the module mounting base plate 1 due to the fact that the crossed roller bearing 5 and the rotating shaft 6 have a certain height, an XY theta axis guide module 4 is arranged in the space, the bottom of the XY theta axis guide module is fixedly connected with the module mounting base plate 1, the top of the XY theta axis guide module is connected with the rotating shaft mounting plate 7, a ball screw mechanism 3 of a driving device is connected with the XY theta axis guide module 4 for driving an X axis module in the XY theta axis guide module 4 to move, so that the rotating shaft mounting plate 7 is acted by an X axis direction in a circumferential direction, and the rotating shaft mounting plate 7 does rotating motion under the limitation of the rotating shaft 6, the XY θ axis guide module 4 has three degrees of freedom of X axis, Y axis and θ, and the top of the XY θ axis guide module is connected with the rotation axis mounting plate 7 in a relatively rotatable manner, so that when the X axis is driven to displace, the Y axis and θ can automatically adjust the displacement and rotation angle within the rotation radius of the rotation axis mounting plate 7 where the XY θ axis guide module 4 is located, so that the rotation axis mounting plate 7 can smoothly complete rotation, and because the process has a very high reduction ratio, the rotation axis mounting plate 7 (i.e., the stage assembly) is endowed with ultrahigh rigidity, thereby effectively avoiding jitter in the process and realizing high-quality wafer detection.

In a specific embodiment, the XY θ axis guide modules 4 may be provided in plurality and on a circle having the rotation axis of the rotation axis mounting plate 7 as the center, the radius of the circle being smaller than the radius of the rotation axis mounting plate 7 so that the XY θ axis guide modules 4 can be fixed in the rotation axis mounting plate 7, preferably, the XY θ axis guide modules 4 are evenly distributed on the circle in an equal division manner, and in this embodiment, 3 XY θ axis guide modules 4 are provided and evenly distributed on the circle in a 3 equal division manner. One of the XY θ axis guide modules 4 is used as a driving end, and the other XY θ axis guide modules 4 are used as driven ends, so that the displacement or rotation angle of X, Y and θ can be automatically adjusted according to the degree of freedom when the rotating shaft mounting plate 7 rotates.

Referring to fig. 2, fig. 2 is a front view of a correction device for wafer inspection according to an embodiment of the present invention, as shown in fig. 2, the ball screw mechanism 3 of the driving device is connected to one of the XY θ axis guide modules 4 for controlling the displacement amount thereof in the X axis direction, which pushes the X-axis displacement of the XY theta axis guide module 4 of the driving end, thereby giving an X-axis thrust to the rotating shaft mounting plate 7 at the XY theta axis guide module 4 and the fixing part thereof, and rotating the rotating mounting plate 7, because the XY theta axis guide module 4 has three degrees of freedom of X-axis, Y-axis and theta, under the restriction of the freedom degrees in the two directions of X, Y, a rotation track on the radius of the fixed part can be formed, and then the fixed part can rotate while being fixed with the rotating shaft mounting plate 7 through the rotation characteristic in the theta direction, so that the problem of incapability of rotating caused by rigid connection is avoided.

In one embodiment, fig. 3 is an exploded view of an XY θ axis guide module in a correction device for wafer inspection according to one embodiment of the present invention, as shown in fig. 3, the XY θ axis guide module 4 includes, from bottom to top, a guide module base 41, an X axis guide module 43, a Y axis guide module 44, and a rotation module 45, the bottom of the guide module base 41 is fixed to the rotation axis mounting plate 7, the upper portion of the guide module base 41 is provided with an X axis guide 42, the bottom of the X axis guide module 43 is provided with a guide rail corresponding to the X axis guide 42, the upper portion is provided with a Y axis guide 42 ', the bottom of the Y axis guide module 44 is provided with a guide rail corresponding to the Y axis guide 42', the rotation module 45 is a bearing, the outer race of the bearing is fixed to the top of the Y-axis guide module 44, the inner race is rotatable relative to the outer race, and the inner race is connected to the rotary shaft mounting plate 7. The X-axis guide module 43, the Y-axis guide module 44 and the rotating module 45 of the XY theta axis guide module have a freedom degree relationship with each other, and the adjustment of the freedom degree can be realized.

Fig. 4 is a schematic structural diagram illustrating a driving device in a correction device for wafer inspection according to an embodiment of the present invention, as shown in fig. 4, a stepping motor mounting seat 31 is disposed at one side of a coupler fixing seat 33 of a ball screw mechanism and fixed on a module mounting base 1 along with the coupler fixing seat 33, a stepping motor 2 is fixed on the stepping motor mounting seat 31 and connected to a coupler 32 disposed in the coupler fixing seat 33 to drive a screw 34 connected to the coupler 32 to rotate, the screw 34 is provided with a screw nut, the screw nut is fixed to a screw nut connecting seat 35, and the screw 34 is rotated to drive the screw nut connecting seat 35 to move integrally.

In a specific embodiment, the lead screw nut connecting seat 35 is fixedly connected with the X-axis guiding module 43 of the XY θ axis guiding module 4 to drive the X-axis guiding module 43 to displace, it should be appreciated that the lead screw nut connecting seat 35 can also be fixedly connected with the Y-axis guiding module 44, and the rotation of the rotating shaft mounting plate 7 can also be realized by means of the other two degrees of freedom.

In a specific embodiment, the vacuum adsorption platform 9 and the platform horizontal adjusting mechanism 8 are arranged on the rotating shaft mounting plate 7, and the vacuum adsorption platform 9 is locked on the support rods of the three platform horizontal adjusting mechanisms 8; when the fine-toothed nuts on the horizontal adjusting mechanism 8 of the carrier are rotated, the fine-toothed nuts drive the supporting rods to stretch, and because the three points determine a plane, the levelness of the vacuum adsorption platform 9 can be adjusted by only rotating the fine-toothed nuts of the horizontal adjusting mechanisms 8 of the carrier. It should be appreciated that the number of the stage horizontal adjusting mechanisms 8 can also be set to be larger than 3 according to the size of the vacuum adsorption platform 9, and the technical effects of the present application can also be achieved.

In a specific embodiment, after the wafer is transferred to the inspection platform, the alignment camera takes several pictures on the wafer edge, and then calculates an angle δ θ between the wafer and the inspection direction through a specific algorithm, and the movement amount of the lead screw nut (i.e. the displacement amount with the X-axis guide module of the XY θ -axis guide module 4) δ X and the rotation angle of the rotation platform satisfy the following mathematical relationship: δ X is R cos (δ θ + θ) -R cos θ, where R is the radius of the circle on which the XY θ axis guide module is located at the rotation axis of the stage assembly, and θ is the angle between the radius of the current position and the X axis, and θ can be understood as the sum of the angular position θ X of the center of the crossed roller bearing connected to the X axis and the table angle θ 0 before operation. By substituting the calculated angle δ θ into the above expression, the relative movement amount of the X axis, that is, the movement amount of the screw nut can be obtained. The relationship between the movement amount δ X of the screw nut (i.e., the relative movement amount of the X axis) and the number of screw rotations n is δ X n × p, where n denotes the number of screw rotations and p denotes the lead of the screw. Therefore, the detection platform can be controlled to rotate by a specific angle by controlling the rotating speed of the stepping motor.

The method aims at the problem that in the prior art, two axes are driven to move simultaneously, and the smoothness of multi-axis combined motion is not good as that of single-axis motion, so that the quality of a shot image is not as good as that of a shot image driven by a single axis; the DD servo motor is used, the motor can be slightly shaken all the time due to the characteristics of the servo motor, the image capturing quality is influenced, the stepping motor is adopted to drive the ball screw to move linearly, complex movement similar to a cam mechanism is realized through X, Y combined guide rails and theta rotation, and the platform is pushed to rotate. The stepping motor can realize zero jitter in a static state, and the jitter problem of the DD servo motor is perfectly solved. In addition, the ultrahigh speed reduction ratio can be realized by converting the linear motion into the rotary motion, the theta axis can be made very thin, and the X, Y combined guide rail is used for guiding, so that the ultrahigh rigidity is given to the platform. Therefore, the problems of angle correction and jitter are solved, and high-quality microscopic detection can be realized.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present invention without departing from the spirit and scope of the invention. In this way, if these modifications and changes are within the scope of the claims of the present invention and their equivalents, the present invention is also intended to cover these modifications and changes. The word "comprising" does not exclude the presence of other elements or steps than those listed in a claim. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims shall not be construed as limiting the scope.