CN115692289A - Silicon wafer alignment device and silicon wafer alignment method - Google Patents

Abstract

The invention provides a silicon wafer alignment device and a silicon wafer alignment method, which are used for aligning and bonding two silicon wafers and comprise the following steps: the two loading modules are oppositely arranged and respectively provided with a loading surface for loading the silicon wafer, and the two loading surfaces are oppositely arranged; at least one aligning contact module arranged on at least one loading module and used for providing jacking force for the silicon wafer; at least one vacuum adsorption structure arranged on the loading surface of the loading module with the alignment contact module, wherein each vacuum adsorption structure is provided with at least two independent vacuum adsorption areas which are in concentric ring shapes; and adjusting the adsorption force of at least part of the vacuum adsorption area of any vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers. The invention reduces the multiple difference between the two silicon chips to improve the alignment bonding precision.

Description

Silicon wafer alignment device and silicon wafer alignment method

Technical Field

The invention relates to the technical field of semiconductors, in particular to a silicon wafer alignment device and a silicon wafer alignment method.

Background

With the rapid development of moore's law in the semiconductor industry, the cost and difficulty of the semiconductor industry in continuing to develop the semiconductor industry are higher and higher. Meanwhile, 3D ICs are increasingly used and proved to be an indispensable complement to moore's law in semiconductor development. In 3D ICs, the alignment bonding process has the advantage of high yield and is increasingly used. The current alignment bonding process has the highest precision of 0.5 μm, and the common structure mainly comprises two oppositely arranged loading modules, two oppositely arranged alignment measurement modules and an alignment contact module, wherein the two oppositely arranged alignment measurement modules are respectively used for measuring the positions of corresponding silicon wafers and obtaining the alignment error information of the two silicon wafers, and the alignment contact module completes the contact bonding of the two silicon wafers after the compensation of a motion platform.

With the development of the industry, the precision requirement of the alignment bonding process is higher and higher, and even the alignment bonding precision of 200nm and above of the whole wafer can be required. But alignment bonding accuracy on the order of 200nm is very difficult to achieve for two reasons. Firstly, two silicon wafers which are fed often have certain multiplying power deviation due to the influence of the previous process; and secondly, when the two silicon wafers are adsorbed on the upper loading module and the lower loading module respectively during alignment bonding, the temperature distribution of the two silicon wafers is different, and the deviation of about 40nm exists on the edges of the 12-inch two silicon wafers by calculating the deviation of 0.1 ℃. Therefore, in order to achieve higher precision alignment bonding, it is necessary to control the difference between the two silicon wafer multiples within an acceptable range before alignment and bonding.

Disclosure of Invention

The invention aims to provide a silicon wafer alignment device and a silicon wafer alignment method, which can reduce the time difference between two silicon wafers so as to improve the alignment bonding precision.

In order to achieve the above object, the present invention provides a silicon wafer alignment apparatus for performing alignment bonding of two silicon wafers, comprising:

the two loading modules are oppositely arranged and respectively provided with a loading surface for loading the silicon wafer, and the two loading surfaces are oppositely arranged;

at least one aligning contact module arranged on at least one loading module and used for providing jacking force for the silicon wafer;

at least one vacuum adsorption structure arranged on the loading surface of the loading module with the alignment contact module, wherein each vacuum adsorption structure is provided with at least two independent vacuum adsorption areas which are in concentric ring shapes;

and adjusting the adsorption force of at least part of the vacuum adsorption area of any vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers, and relatively moving the two loading modules so as to align and bond the two silicon wafers.

Optionally, the magnification value of the silicon wafer is obtained before the silicon wafer is loaded to the loading module.

Optionally, the two loading modules are respectively a first loading module and a second loading module, the alignment contact module is disposed on the first loading module, and the first loading module is used for loading a silicon wafer with a smaller magnification value.

Optionally, the wafer processing system further comprises at least two alignment measurement modules, which are arranged on the two loading modules and used for acquiring a magnification value of the silicon wafer.

Optionally, the alignment contact module is disposed on each of the two loading modules.

Optionally, the alignment contact module is disposed on any one of the loading modules; the silicon wafer aligning device further comprises a temperature control module which is arranged on any one of the loading modules and used for adjusting the temperature of the bearing surface of the loading module.

Optionally, the loading device further comprises a moving table for driving at least one loading module to move.

Optionally, the vacuum adsorption area includes a first vacuum adsorption area and at least one second vacuum adsorption area, and the second vacuum adsorption area sequentially surrounds the first vacuum adsorption area to form a concentric ring shape.

A silicon wafer alignment method using the silicon wafer alignment apparatus as described above, comprising:

providing two silicon wafers, respectively loading the two silicon wafers onto two bearing surfaces, and acquiring multiplying power values of the two silicon wafers;

adjusting the adsorption force of at least part of the vacuum adsorption area of any vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers;

and the two loading modules move relatively to carry out alignment bonding on the two silicon wafers.

Optionally, the two loading modules are respectively a first loading module and a second loading module, the alignment contact module is arranged on the first loading module, the first loading module is used for loading a silicon wafer with a smaller magnification value, and the magnification value of the silicon wafer is obtained before the silicon wafer is loaded to the loading module; and (c) a second step of,

and adjusting the vacuum adsorption structure on the loading surface of the first loading module.

Optionally, the wafer processing system further comprises at least two alignment measurement modules, which are arranged on the two loading modules and used for acquiring the magnification value of the silicon wafer, wherein the two loading modules are both provided with the alignment contact module; and the number of the first and second groups,

and adjusting the vacuum adsorption structure on the loading surface of the silicon wafer with a smaller loading multiplying factor value.

Optionally, the wafer processing system further comprises at least two alignment measurement modules, which are arranged on the two loading modules and used for acquiring the magnification value of the silicon wafer, wherein the alignment contact module is arranged on any one of the loading modules; and the number of the first and second groups,

when a loading module arranged in the alignment contact module loads a silicon wafer with a smaller multiplying power value, adjusting the vacuum adsorption structure on the loading surface of the loading module; and when the loading module arranged by aligning the contact module loads the silicon wafer with a larger multiplying factor value, adjusting the temperature of any one silicon wafer and adjusting the vacuum adsorption structure on the loading surface of the loading module.

Optionally, adjusting the temperature of any one of the silicon wafers includes decreasing the temperature of the silicon wafer with the larger magnification value or increasing the temperature of the silicon wafer with the smaller magnification value.

In the silicon wafer alignment device and the silicon wafer alignment method provided by the invention, the alignment contact module is arranged on at least one loading module, the loading surface of the loading module with the alignment contact module is provided with a vacuum adsorption structure, the vacuum adsorption structure is provided with at least two independent concentric annular vacuum adsorption areas, the adsorption force of at least part of the vacuum adsorption areas of any vacuum adsorption structure is adjusted according to the multiplying power values of two silicon wafers, and the jacking force is provided for the silicon wafers by combining the alignment contact module so as to realize the adjustment of the multiplying power values of the silicon wafers, thereby reducing the difference of the multiplying power values between the two silicon wafers, namely reducing the multiplying power difference between the two silicon wafers, and improving the alignment bonding precision when the alignment bonding is carried out.

Drawings

Fig. 1 is a schematic structural diagram of a silicon wafer alignment apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic view of a vacuum adsorption structure in a silicon wafer alignment apparatus according to an embodiment of the present invention;

fig. 3 and fig. 4 are schematic position diagrams of the silicon wafer alignment apparatus according to an embodiment of the present invention when measuring the silicon wafer magnification value;

FIG. 5 is a flowchart of a silicon wafer alignment method according to an embodiment of the present invention;

fig. 6 is a schematic diagram illustrating adjustment of a magnification value of a silicon wafer by using the silicon wafer alignment method according to an embodiment of the present invention;

wherein the reference numerals are:

101. 201-a silicon wafer; 111. 112, 211, 212-alignment marks; 102. 202-load module; 103. 203-alignment measurement module; 104-aligning the contact module; 204-motion stage.

Detailed Description

The following describes in more detail embodiments of the present invention with reference to the schematic drawings. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is provided for the purpose of facilitating and clearly illustrating embodiments of the present invention.

Fig. 1 is a schematic structural diagram of a silicon wafer alignment apparatus provided in this embodiment, and fig. 2 is a schematic structural diagram of a vacuum adsorption structure in the silicon wafer alignment apparatus provided in this embodiment. Referring to fig. 1 and 2, the present embodiment provides a silicon wafer alignment apparatus for performing alignment bonding on two silicon wafers 101 and 201, which includes two oppositely disposed loading modules 102 and 202, at least one alignment contact module 104, and at least one vacuum adsorption structure.

The two loading modules 102 and 202 are vertically arranged up and down relatively, and each loading module has a loading surface for loading silicon wafers, and the two loading surfaces are arranged oppositely. At least two alignment marks are arranged on the two silicon wafers 101 and 201, and the positions of all the alignment marks on the two silicon wafers 101 and 201 are the same. In fig. 1, only two alignment marks are shown for each silicon wafer, that is, two alignment marks 111 and 112 are provided on the silicon wafer 101, two alignment marks 211 and 212 are provided on the silicon wafer 201, and the positions of the two alignment marks 111 and 112 on the silicon wafer 101 are the same as the positions of the two alignment marks 211 and 212 on the silicon wafer 201, that is, the distance between the two alignment marks 111 and 112 on the silicon wafer 101 is the same as the distance between the two alignment marks 211 and 212 on the silicon wafer 201.

And the alignment contact module is arranged on at least one loading module and used for providing jacking force for the silicon wafer arranged on the loading module. In fig. 1, the loading module 102 is shown to be provided with an alignment contact module 104 for providing a downward urging force to the silicon wafer 101, and the loading module 202 may also be provided with an alignment contact module.

A vacuum adsorption structure is arranged on the loading surface of the loading module with the alignment contact module, the vacuum adsorption structure is provided with at least two independent concentric annular vacuum adsorption areas, and any silicon wafer is loaded on the loading surface of the loading module with the alignment contact module through the vacuum adsorption structure; the loading surface of the loading module without the alignment contact module is not provided with a vacuum adsorption structure, and another silicon wafer is loaded on the loading surface of another loading module in a conventional adsorption mode. A vacuum adsorption structure is provided on a loading surface of the loading module 102 of the alignment contact module 104 in fig. 1, and the silicon wafer 101 is loaded on the loading module 102 through the vacuum adsorption structure.

In this embodiment, the vacuum absorption areas include a first vacuum absorption area and at least one second vacuum absorption area, and the second vacuum absorption area sequentially surrounds the first vacuum absorption area to form a concentric ring shape, and at least two independent vacuum absorption areas are concentric ring shapes, so that magnification adjustment can be performed uniformly for different areas of the silicon wafer. Fig. 2 shows three independent vacuum suction areas 102a, 102b, and 102c of the vacuum suction structure on the loading surface of the loading module 102, the vacuum degrees of the three vacuum suction areas 102a, 102b, and 102c may be set to be the same or different according to actual conditions, the vacuum suction area 102a is a first vacuum suction area, both the two vacuum suction areas 102b and 102c are second vacuum suction areas, the vacuum suction area 102a is circular, and the two vacuum suction areas 102b and 102c are annular and sequentially surround the vacuum suction area 102a to form a concentric ring shape.

In this embodiment, the first example may obtain the multiplier values of the two silicon wafers 101, 201 before loading the two silicon wafers 101, 201 into the two loading modules 102, 202, respectively. The two loading modules 102 and 202 are respectively a first loading module and a second loading module, the alignment contact module is arranged on the first loading module, and the first loading module is used for loading the silicon wafer with a smaller magnification value. In fig. 1, a loading module 101 is a first loading module, a loading module 102 is a second loading module, an alignment contact module 104 is disposed on the loading module 101, and the loading module 101 is used for loading a silicon wafer 101 with a smaller magnification value, and a vacuum adsorption structure on a loading surface of the loaded silicon wafer 101 is adjusted according to a difference between the magnification values of the two silicon wafers 101 and 201, specifically, an adsorption force of at least a partial vacuum adsorption region in the vacuum adsorption structure is adjusted, where adjusting the adsorption force is adjusting a vacuum degree of the vacuum adsorption region. Adjusting the adsorption force of at least part of the vacuum adsorption area of the vacuum adsorption structure corresponding to the silicon wafer 101 and providing a jacking force for the silicon wafer 101 by combining the alignment contact module 104, wherein the directions of the adsorption force and the jacking force are opposite, and stretching the silicon wafer 101 to increase the magnification value of the silicon wafer 101, so that the difference of the magnification values between the two silicon wafers 101 and 201 is reduced, namely the magnification difference between the two silicon wafers 101 and 201 is reduced, and the alignment bonding precision is improved.

In this embodiment, the second example may include at least two alignment measurement modules 103 and 203 respectively disposed on the two loading modules 102 and 202 for obtaining the magnification values of the two silicon wafers 101 and 201. Namely, each loading module is connected with at least one alignment measurement module, and when each loading module is connected with a plurality of alignment measurement modules, the plurality of alignment measurement modules can simultaneously carry out partition measurement on the silicon wafer. In fig. 1, each load module is shown connected to only one alignment measurement module, i.e. load module 102 is connected to alignment measurement module 103 and load module 202 is connected to alignment measurement module 203.

Further, the two loading modules 102 and 202 are both provided with an alignment contact module (only one alignment contact module 104 is shown in fig. 1), the magnification values of the two silicon wafers 101 and 201 can be obtained through measurement by the two alignment measurement modules 103 and 203, and the vacuum adsorption structure on the loading surface of the silicon wafer with the small magnification value is adjusted according to the difference between the magnification values of the two silicon wafers 101 and 201, specifically, the adsorption force of at least part of the vacuum adsorption region in the vacuum adsorption structure is adjusted, which is to adjust the vacuum degree of the vacuum adsorption region. Adjusting the adsorption force of at least part of the vacuum adsorption area of the vacuum adsorption structure corresponding to the silicon wafer with a small magnification value, and providing a jacking force for the silicon wafer by combining with the alignment contact module corresponding to the silicon wafer with the small magnification value, wherein the directions of the adsorption force and the jacking force are opposite, and stretching the silicon wafer with the small magnification value to increase the magnification value of the silicon wafer with the small magnification value, so that the difference of the magnification values between the two silicon wafers 101 and 201 is reduced, namely, the magnification difference between the two silicon wafers 101 and 201 is reduced, and the alignment bonding precision is improved.

In this embodiment, the third example may include at least two alignment measurement modules 103 and 203 respectively disposed on the two loading modules 102 and 202 for obtaining the magnification values of the two silicon wafers 101 and 201. That is, each loading module is connected with at least one alignment measurement module, and when each loading module is connected with a plurality of alignment measurement modules, the plurality of alignment measurement modules can simultaneously perform partition measurement on the silicon wafer. In fig. 1, each load module is shown connected to only one alignment measurement module, i.e. load module 102 is connected to alignment measurement module 103 and load module 202 is connected to alignment measurement module 203.

Further, an alignment contact module is disposed on any of the loading modules. Furthermore, the silicon wafer alignment device also comprises a temperature control module which is arranged on any loading module and used for adjusting the temperature of the loading surface of the loading module. In this embodiment, the temperature control module is disposed on any one of the loading modules, but the temperature control module may be disposed on each loading module according to actual conditions.

Specifically, the two loading modules 102 and 202 are respectively a first loading module and a second loading module, and when the alignment contact module is disposed on the first loading module, a temperature control module may be disposed on the second loading module for adjusting the temperature of the bearing surface of the second loading module, so as to raise the temperature of the silicon wafer on the bearing surface of the second loading module, and the raised temperature may increase the magnification value of the silicon wafer on the bearing surface of the second loading module. For example, in fig. 1, only when the alignment contact module 104 is disposed on the loading module 102, the temperature control module is disposed on the loading module 202, and the magnification values of the two silicon wafers 101 and 201 can be obtained by measuring through the two alignment measurement modules 103 and 203, and when the magnification value of the silicon wafer 101 is greater than the magnification value of the silicon wafer 201, the temperature control module is configured to control the temperature of the silicon wafer 201 on the bearing surface of the loading module 202, so as to raise the temperature of the silicon wafer 201, and increase the magnification value of the silicon wafer 201 by thermal expansion and cold contraction, so that the magnification value of the silicon wafer 101 is less than the magnification value of the silicon wafer 201.

Or, when the alignment contact module is disposed on the first loading module, the temperature control module may be disposed on the first loading module, and configured to adjust the temperature of the loading surface of the first loading module, so as to lower the temperature of the silicon wafer on the loading surface of the first loading module, and the reduction in temperature may reduce the magnification value of the silicon wafer on the loading surface of the first loading module. For example, in fig. 1, only when the alignment contact module 104 is disposed on the loading module 102, the temperature control module is disposed on the loading module 102, and the magnification values of the two silicon wafers 101 and 201 can be obtained through measurement by the two alignment measurement modules 103 and 203, and when the magnification value of the silicon wafer 101 is greater than the magnification value of the silicon wafer 201, the temperature control module is configured to control the temperature of the silicon wafer 101 on the bearing surface of the loading module 102, so as to lower the temperature of the silicon wafer 101, and reduce the magnification value of the silicon wafer 101 due to thermal expansion and cold contraction, so that the magnification value of the silicon wafer 101 is less than the magnification value of the silicon wafer 201.

Further, after the rate value of the silicon wafer 101 is smaller than the rate value of the silicon wafer 201, the vacuum adsorption structure on the loading surface of the silicon wafer 101 is adjusted according to the difference between the rate values of the two silicon wafers 101 and 201, specifically, the adsorption force of at least a part of the vacuum adsorption regions in the vacuum adsorption structure is adjusted, and adjusting the adsorption force is to adjust the vacuum degree of the vacuum adsorption regions. Adjusting the adsorption force of at least part of the vacuum adsorption area of the vacuum adsorption structure corresponding to the silicon wafer 101 and providing a jacking force for the vacuum adsorption structure in combination with the alignment contact module 104 corresponding to the silicon wafer 101, wherein the directions of the adsorption force and the jacking force are opposite, and stretching the silicon wafer 101 to increase the magnification value of the silicon wafer 101, so that the difference of the magnification values between the two silicon wafers 101 and 201 is reduced, namely, the magnification difference between the two silicon wafers 101 and 201 is reduced, and the alignment bonding precision is improved. The magnification difference between the two silicon wafers 101 and 201 is more accurate than the magnification difference between the two silicon wafers 101 and 201 only through the temperature control module by matching the vacuum adsorption area and the alignment contact module.

Further, the silicon wafer alignment device also comprises a moving table which is used for driving at least one loading module to move, and the two loading modules are relatively moved under the driving of the moving table and the alignment contact module so as to enable the two silicon wafers to be aligned and bonded. When the alignment contact module is disposed on the motion stage, the alignment contact module is located between the motion stage and the loading module. In fig. 1, the alignment contact module 104 is used to drive the silicon chip 101 to approach the silicon chip 201, so that the silicon chip 101 and the silicon chip 201 are aligned and bonded. The moving table 204 is used for driving the loading module 202 and the alignment measurement module 203 to move, so that the alignment measurement modules 103 and 203 obtain the position information of all the alignment marks and the silicon wafer 101 and the silicon wafer 201 are aligned and bonded.

Fig. 3 and fig. 4 are schematic position diagrams of the silicon wafer alignment apparatus provided in this embodiment when measuring the silicon wafer magnification value. Referring to fig. 3, the moving stage 204 drives the loading module 202 and the alignment measurement module 203 to move, so that the alignment measurement module 103 is aligned with the two alignment marks 211 and 212, respectively, and position information of the two alignment marks 211 and 212 is obtained; referring to fig. 4, the moving stage 204 drives the loading module 202 and the alignment measurement module 203 to move, so that the alignment measurement module 203 is aligned with the two alignment marks 111 and 112, respectively, and position information of the two alignment marks 111 and 112 is obtained, wherein a distance between the two alignment marks 211 and 212 is a value of a multiple of the silicon wafer 201, and a distance between the two alignment marks 111 and 112 is a value of a multiple of the silicon wafer 101.

Fig. 5 is a flowchart of a silicon wafer alignment method provided in this embodiment. Referring to fig. 5, the present embodiment further provides a silicon wafer alignment method using the silicon wafer alignment apparatus, where the silicon wafer alignment method includes:

step S1: providing two silicon wafers, respectively loading the two silicon wafers onto two bearing surfaces, and acquiring multiplying power values of the two silicon wafers;

step S2: adjusting the adsorption force of at least part of the vacuum adsorption area of any vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers;

and step S3: and the two loading modules move relatively to carry out alignment bonding on the two silicon wafers.

The silicon wafer alignment method provided in this embodiment will be described in detail below.

Executing the step S1: providing two silicon chips, wherein at least two alignment marks are arranged on each silicon chip, and the positions of all the alignment marks on the two silicon chips are the same, so that the distance between every two alignment marks on the two silicon chips is the same. The distance value of any two alignment marks on the silicon wafer is the multiplying power value of the silicon wafer, if the distance of any two alignment marks on the silicon wafer actually deviates, it is indicated that the multiplying power difference occurs between the two silicon wafers, and the multiplying power difference may be caused by the influence of the previous process or the deviation caused by the difference of the temperatures of the two loading modules, so that the multiplying power difference needs to be compensated to reduce the multiplying power difference between the two silicon wafers.

In this embodiment, the first example may obtain the magnification values of the two silicon wafers before the two silicon wafers are respectively loaded into the two loading modules, and the user may specify the magnification values of the two silicon wafers according to the previous process requirements, for example, specify the magnification values of the two silicon wafers after the previous test according to the saved magnification values. The two loading modules are respectively a first loading module and a second loading module, the aligning contact module is arranged on the first loading module, and the first loading module is used for loading the silicon wafer with a smaller multiplying factor value.

In this embodiment, the second example may further include at least two alignment measurement modules, which are disposed on the two loading modules and are used to obtain the magnification values of the two silicon wafers, specifically, the alignment measurement modules are used to obtain position information of all alignment marks on the two silicon wafers, and a distance value between any two alignment marks on the silicon wafers is calculated and obtained as the magnification value of the silicon wafer. And the two loading modules are respectively provided with an aligning contact module, and the two silicon wafers are respectively loaded on the two loading modules.

In this embodiment, the third example may further include at least two alignment measurement modules, which are disposed on the two loading modules and are used to obtain the magnification values of the two silicon wafers, specifically, the alignment measurement modules are used to obtain position information of all alignment marks on the two silicon wafers, and a distance value between any two alignment marks on the silicon wafers is calculated and obtained as the magnification value of the silicon wafer. And the aligning contact module is arranged on any loading module, and the two silicon wafers are respectively loaded on the two loading modules.

And executing the step S2: and adjusting the adsorption force of at least part of the vacuum adsorption area of the vacuum adsorption structure on the loading surface of the silicon wafer with the smaller loading rate value according to the difference value of the rate values of the two silicon wafers so as to reduce the difference value of the rate values of the two silicon wafers. Because the multiplying power values of the two silicon wafers are difficult to be adjusted to be completely the same, a threshold value can be set, and if the difference value of the multiplying power values of the two silicon wafers is larger than the threshold value, the adsorption force of at least part of the vacuum adsorption area of the vacuum adsorption structure on the loading surface of the silicon wafer with the smaller loading multiplying power value needs to be adjusted according to the difference value of the multiplying power values of the two silicon wafers.

In the present embodiment, the first example adjusts the suction force of at least a part of the vacuum suction region of the vacuum suction structure on the loading surface of the first loading module according to the difference in the magnification values of the two silicon wafers. Applying a jacking force to the silicon wafer on the loading surface of the first loading module by using the alignment contact module, wherein the loading surface of the first loading module is provided with an adsorption force for adsorbing the silicon wafer, and the direction of the adsorption force is opposite to that of the jacking force; the vacuum degree of at least part of the vacuum adsorption area of the vacuum adsorption structure on the loading surface of the first loading module can be adjusted according to the difference value of the multiplying power values of the two silicon wafers, so that the adsorption force of at least part of the vacuum adsorption area can be changed, and the difference value of the multiplying power values of the two silicon wafers is reduced.

In this embodiment, the second example adjusts the suction force of at least a part of the vacuum suction region of the vacuum suction structure on the loading surface of the silicon wafer having a smaller loading magnification value according to the difference between the magnification values of the two silicon wafers. Applying a jacking force to the silicon wafer on the loading surface of the silicon wafer with the smaller multiplying power value by using the alignment contact module, wherein the loading surface of the silicon wafer with the smaller multiplying power value is provided with an adsorption force for adsorbing the silicon wafer, and the direction of the adsorption force is opposite to that of the jacking force; the vacuum degree of at least part of the vacuum adsorption area of the vacuum adsorption structure on the loading surface of the silicon wafer with a smaller multiplying factor value is adjusted according to the difference value of the multiplying factor values of the two silicon wafers, so that the adsorption force of at least part of the vacuum adsorption area can be changed, and the difference value of the multiplying factor values of the two silicon wafers is reduced.

In this embodiment, the third example adjusts the suction force of at least a part of the vacuum suction region of the vacuum suction structure on the loading surface of the silicon wafer having a smaller loading magnification value according to the difference in magnification values of two silicon wafers. When a loading module arranged on the alignment contact module loads a silicon wafer with a smaller multiplying power value, the alignment contact module is utilized to apply a jacking force to the silicon wafer on the loading surface of the silicon wafer with the smaller multiplying power value, and the loading surface of the silicon wafer with the smaller multiplying power value is provided with an adsorption force for adsorbing the silicon wafer, wherein the direction of the adsorption force is opposite to that of the jacking force; the vacuum degree of at least part of the vacuum adsorption area of the vacuum adsorption structure on the loading surface of the silicon wafer with a smaller multiplying factor value is adjusted according to the difference value of the multiplying factor values of the two silicon wafers, so that the adsorption force of at least part of the vacuum adsorption area can be changed, and the difference value of the multiplying factor values of the two silicon wafers is reduced.

When the loading module arranged in the alignment contact module loads the silicon wafer with a larger multiplying power value, the temperature of the silicon wafer with the larger multiplying power value can be reduced, thermal expansion and cold contraction are generated, and the multiplying power value of the silicon wafer is reduced, so that the multiplying power value of the silicon wafer loaded by the loading module arranged in the alignment contact module is smaller than that of the silicon wafer loaded by the loading module not provided with the alignment contact module. Furthermore, the aligning contact module is used for applying a jacking force to the silicon wafer on the loading surface of the silicon wafer with the smaller multiplying power value, the loading surface of the silicon wafer with the smaller multiplying power value is provided with an adsorption force for adsorbing the silicon wafer, and the direction of the adsorption force is opposite to that of the jacking force; because the vacuum adsorption area on the silicon wafer loading surface with the smaller multiplying power value is provided with at least two vacuum adsorption areas, the vacuum adsorption areas are used for adsorbing the silicon wafer, the fact that the silicon wafer is adsorbed and controlled by different vacuum adsorption areas can be known, which vacuum adsorption area the alignment mark corresponds to can be known from the position of the alignment mark on the silicon wafer, the vacuum degree of at least part of the vacuum adsorption area on the silicon wafer loading surface with the smaller multiplying power value is adjusted according to the difference value of the multiplying power values of the two silicon wafers, the vacuum degree of the vacuum adsorption area corresponding to the position of the alignment mark can be adjusted, the adsorption force of at least part of the vacuum adsorption area is changed, and the difference value of the multiplying power values of the two silicon wafers is reduced.

Or when the loading module arranged in the alignment contact module loads the silicon wafer with a larger multiplying power value, the temperature of the silicon wafer loaded by the loading module not provided with the alignment contact module can be increased to generate thermal expansion and cold contraction, and the multiplying power value of the silicon wafer is increased, so that the multiplying power value of the silicon wafer loaded by the loading module arranged in the alignment contact module is smaller than that of the silicon wafer loaded by the loading module not provided with the alignment contact module. Furthermore, the aligning contact module is used for applying a jacking force to the silicon wafer on the loading surface of the silicon wafer with the smaller multiplying power value, the loading surface of the silicon wafer with the smaller multiplying power value is provided with an adsorption force for adsorbing the silicon wafer, and the direction of the adsorption force is opposite to that of the jacking force; because the vacuum adsorption area on the silicon wafer loading surface with the smaller multiplying power value is provided with at least two vacuum adsorption areas, the vacuum adsorption areas are used for adsorbing the silicon wafer, the fact that the silicon wafer is adsorbed and controlled by different vacuum adsorption areas can be known, which vacuum adsorption area the alignment mark corresponds to can be known from the position of the alignment mark on the silicon wafer, the vacuum degree of at least part of the vacuum adsorption area on the silicon wafer loading surface with the smaller multiplying power value is adjusted according to the difference value of the multiplying power values of the two silicon wafers, the vacuum degree of the vacuum adsorption area corresponding to the position of the alignment mark can be adjusted, the adsorption force of at least part of the vacuum adsorption area is changed, and the difference value of the multiplying power values of the two silicon wafers is reduced. In this embodiment, it is preferable to adjust the temperature of any one silicon wafer first, then adjust the vacuum adsorption structure to reduce the difference between the two magnification values of the two silicon wafers, but the present invention is not limited to this adjustment sequence, and it is also possible to adjust the vacuum adsorption structure first, then adjust the temperature of any one silicon wafer, and finally adjust the vacuum adsorption structure to finally reduce the difference between the two magnification values of the two silicon wafers, which is determined by actual conditions.

In this embodiment, in order to increase the magnification value of a silicon wafer having a small magnification value, the difference between the magnification values of the two silicon wafers is decreased. Therefore, the silicon wafer with a small magnification value needs to be stretched to increase the magnification value, the vacuum degree of any vacuum adsorption area is reduced according to the difference between the magnification values of the two silicon wafers, any vacuum adsorption area is a vacuum adsorption area corresponding to the alignment mark position, the vacuum degree of any vacuum adsorption area is reduced to reduce the adsorption force of the vacuum adsorption area, the adsorption force on the position of the silicon wafer corresponding to the vacuum adsorption area is reduced, the adsorption force on the other vacuum adsorption areas is greater than that on the silicon wafer corresponding to the adjusted vacuum adsorption area, the top force applied by the alignment contact module is applied on the position of the silicon wafer corresponding to the adjusted vacuum adsorption area, the edge on the silicon wafer corresponding to the adjusted vacuum adsorption area is subjected to the adsorption force on the position of the silicon wafer corresponding to the other vacuum adsorption areas, the top force is opposite to the adsorption force applied by the alignment contact module, the edge on the position of the silicon wafer corresponding to the adjusted vacuum adsorption area is subjected to the adsorption force on the position of the silicon wafer corresponding to the other vacuum adsorption areas, and the magnification value of the silicon wafer corresponding to be aligned is increased, and the bonding precision of the two silicon wafers is increased.

In this embodiment, the vacuum degree of any vacuum adsorption area is reduced according to the difference between the magnification values of the two silicon wafers, and any vacuum adsorption area is a vacuum adsorption area corresponding to the alignment mark position, and the vacuum degrees of the vacuum adsorption areas corresponding to the alignment mark position can also be reduced while the vacuum degrees of other vacuum adsorption areas are increased, so as to increase the adsorption force of the edge of the silicon wafer corresponding to the position of the adjusted vacuum adsorption area, so that the stretching effect of the silicon wafer is improved, and how to adjust the adsorption force of at least part of the vacuum adsorption areas is determined according to the actual situation.

Fig. 6 is a schematic diagram of adjusting the magnification value of the silicon wafer by the silicon wafer alignment method provided in this embodiment. Referring to fig. 6, the vacuum adsorption structure of the loading module for adsorbing the silicon wafer 101 has three vacuum adsorption regions for adsorbing the silicon wafer 101, and the silicon wafer 101 can be divided into three corresponding adsorption regions 101a, 101b, and 101c (corresponding to the three vacuum adsorption regions 102a, 102b, and 102c of fig. 2). If the rate value of the silicon wafer 101 needs to be increased, for example, the adsorption force at the adsorption region 101a may be decreased, that is, the vacuum degree of the vacuum adsorption region corresponding to the adsorption region 101a is decreased, the alignment contact module may provide a downward top force F1 to the adsorption region 101a, the adsorption force at the adsorption region 101b is greater than the adsorption force at the adsorption region 101a, the edge of the adsorption region 101a may also receive an upward adsorption force F2 from the adsorption region 101b, the downward top force F1 and the upward adsorption force F2 determine the stretching degree of the adsorption region 101a, the stretching degree may be determined by adjusting the vacuum degree of the vacuum adsorption region corresponding to the adsorption region 101a, the relationship between the stretching degree and the vacuum degrees of different vacuum adsorption regions may be obtained by off-line calibration, the adjusted vacuum degree may be directly known according to the required stretching degree, and the stretching degree determines the rate difference between the two silicon wafers 101 and 201, so the rate value of the silicon wafer 101 is increased, and the rate difference between the two silicon wafers 101 and 201 is decreased.

Executing the step S3: the silicon chip aligning device also comprises a moving table which is used for driving at least one loading module to move, and the two loading modules move relatively under the driving of the moving table and the aligning contact module so as to align and bond the two silicon chips.

In summary, in the silicon wafer alignment apparatus and the silicon wafer alignment method provided by the present invention, the alignment contact module is disposed on at least one loading module, the loading surface of the loading module having the alignment contact module is provided with a vacuum adsorption structure, the vacuum adsorption structure has at least two independent concentric annular vacuum adsorption regions, the adsorption force of at least a part of the vacuum adsorption region of any vacuum adsorption structure is adjusted according to the magnification values of the two silicon wafers, and a jacking force is provided to the silicon wafer by combining the alignment contact module to adjust the magnification value of the silicon wafer, so as to reduce the difference of the magnification values between the two silicon wafers, i.e., reduce the difference of the magnification values between the two silicon wafers, and improve the alignment bonding precision when performing the alignment bonding.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It will be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (13)

1. A silicon wafer alignment device for aligning and bonding two silicon wafers is characterized by comprising:

the two oppositely arranged loading modules are respectively provided with a loading surface for loading the silicon wafer, and the two loading surfaces are oppositely arranged;

at least one aligning contact module arranged on at least one loading module and used for providing jacking force for the silicon wafer;

at least one vacuum adsorption structure arranged on the loading surface of the loading module with the alignment contact module, wherein each vacuum adsorption structure is provided with at least two independent vacuum adsorption areas which are in concentric ring shapes;

and adjusting the adsorption force of at least part of the vacuum adsorption area of any one vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers, and relatively moving the two loading modules so as to align and bond the two silicon wafers.

2. The wafer alignment apparatus of claim 1, wherein a magnification value of the wafer is acquired before the wafer is loaded into the loading module.

3. The wafer alignment apparatus of claim 2, wherein the two loading modules are a first loading module and a second loading module, respectively, the alignment contact module is disposed on the first loading module, and the first loading module is configured to load a wafer having a smaller magnification value.

4. The silicon wafer aligning apparatus of claim 1, further comprising at least two alignment measurement modules disposed on the two loading modules for obtaining a magnification value of the silicon wafer.

5. The wafer alignment apparatus of claim 4, wherein the alignment contact module is disposed on both of the loading modules.

6. The wafer alignment apparatus of claim 4, wherein the alignment contact module is disposed on any one of the loading modules; the silicon wafer aligning device further comprises a temperature control module which is arranged on any one of the loading modules and used for adjusting the temperature of the bearing surface of the loading module.

7. The wafer alignment apparatus of claim 1, further comprising a motion stage for driving at least one of the loading modules to move.

8. The wafer alignment apparatus of claim 1, wherein the vacuum adsorption region comprises a first vacuum adsorption region and at least one second vacuum adsorption region, the second vacuum adsorption region sequentially surrounding the first vacuum adsorption region to form a concentric ring shape.

9. A silicon wafer alignment method using the silicon wafer alignment apparatus according to any one of claims 1 to 8, comprising:

providing two silicon wafers, respectively loading the two silicon wafers onto two bearing surfaces, and acquiring multiplying power values of the two silicon wafers;

adjusting the adsorption force of at least part of the vacuum adsorption area of any vacuum adsorption structure according to the multiplying power values of the two silicon wafers so as to reduce the difference value of the multiplying power values of the two silicon wafers;

and the two loading modules move relatively to carry out alignment bonding on the two silicon wafers.

10. The silicon wafer alignment method according to claim 9, wherein the two loading modules are a first loading module and a second loading module, respectively, the alignment contact module is disposed on the first loading module, and the first loading module is configured to load a silicon wafer with a smaller magnification value, and the magnification value of the silicon wafer is obtained before the silicon wafer is loaded to the loading module; and the number of the first and second groups,

and adjusting the vacuum adsorption structure on the loading surface of the first loading module.

11. The silicon wafer alignment method according to claim 9, further comprising at least two alignment measurement modules disposed on the two loading modules for obtaining a magnification value of the silicon wafer, wherein the two loading modules are each provided with the alignment contact module; and the number of the first and second groups,

and adjusting the vacuum adsorption structure on the loading surface of the silicon wafer with a smaller loading multiplying factor value.

12. The silicon wafer alignment method according to claim 9, further comprising at least two alignment measurement modules disposed on the two loading modules for obtaining magnification values of the silicon wafer, wherein the alignment contact module is disposed on any one of the loading modules; and (c) a second step of,

when a loading module arranged in the alignment contact module loads a silicon wafer with a smaller multiplying power value, adjusting the vacuum adsorption structure on the loading surface of the loading module; and when the loading module arranged by aligning the contact module loads the silicon wafer with a larger multiplying factor value, adjusting the temperature of any one silicon wafer and adjusting the vacuum adsorption structure on the loading surface of the loading module.

13. The wafer alignment method of claim 12, wherein adjusting the temperature of any one of the wafers comprises lowering the temperature of the wafer with the larger magnification value or raising the temperature of the wafer with the smaller magnification value.

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