High-temperature deformation self-compensation algorithm in wafer bonding process

Abstract

The invention provides a high-temperature deformation self-compensation algorithm in a wafer bonding process, and the algorithm comprises the following steps: heating a wafer support plate, and obtaining the deformation of the wafer support plate at different temperatures in the heating process; constructing a temperature deformation quantity change curve of the deformation quantity along with the temperature change; dividing the temperature deformation quantity change curve into a plurality of sections of continuous temperature interval deformation slopes; in the wafer bonding pressurization process, the actual temperature of the wafer carrier plate is detected in real time, the temperature interval to which the actual temperature belongs is found out, and the corresponding expansion type deformation compensation value of the wafer carrier plate is calculated; the control system controls the press-fit device to perform corresponding press-in amount deformation compensation, so that the preset press-in amount is always kept in the temperature rise process of the wafer carrier plate, accurate press-fit track control is performed, and the quality and stability of product production and processing are ensured.

Description

Technical Field

[0001] The present invention relates to the field of wafer bonding, and in particular to a high-temperature deformation self-compensation algorithm for a wafer bonding process. Background Art

[0002] Wafer bonding refers to the process of directly bonding two flat wafers together and then applying external conditions such as pressure and heating to create a bonding force between the two wafers, so that the bond between the two surfaces reaches a certain strength. Wafer bonding is the key to the integrated development and practical application of semiconductor manufacturing technology.

[0003] Currently, the mainstream wafer sizes on the market are between 6-12 inches, with diameters ranging from 150-300mm. Many links in the wafer processing process involve high-temperature heating, baking and cooling. During the heating process, the wafer carrier will produce irregular expansion and deformation in a high-temperature environment, which is particularly prominent in the processing and production of wafers ≥12 inches. Uncontrollable factors will appear in the process sections that require position and pressure control, especially having a great impact on the reliability of wafer bonding, resulting in the inability to improve the processing yield of the product. Summary of the Invention

[0004] A deformation compensation algorithm is proposed to solve the unstable expansion of the carrier board in a high-temperature environment during the board-level wafer bonding process.

[0005] A high-temperature deformation self-compensation algorithm for wafer bonding process, including:

[0006] Step S1, heating the wafer carrier to obtain the deformation of the wafer carrier at different temperatures during the heating process; Step S2, constructing a temperature deformation variation curve of the deformation as the deformation varies with temperature;

[0007] Step S3, such as Figure 2 As shown, the temperature deformation variation curve is divided into multiple continuous temperature interval deformation slopes;

[0008] Step S4: During the wafer bonding pressurization process, the actual temperature of the wafer carrier is detected in real time, the temperature range to which the actual temperature belongs is found, and the corresponding wafer carrier expansion deformation compensation value Pos is calculated, Pos=H 基准 -H n -(H n+1 -H n ) / (C n+1 -C n )*(Ccurrent-C n );

[0009] Among them H 基准 Indicates the deformation at room temperature, Hn indicates the starting deformation value of the current temperature range, C n Indicates the starting temperature of the current temperature interval, Hn+1 indicates the starting deformation value of the next temperature interval, Cn+1 Indicates the starting temperature of the next temperature interval, C 当前 Indicates the current temperature value;

[0010] In step S5 , the control system controls the pressing device to perform corresponding pressing amount deformation compensation, so that the predetermined pressing amount is always maintained during the wafer carrier temperature rising process.

[0011] The beneficial effects of the scheme of the present invention are as follows: the present invention uses a multi-point sampling method to obtain a corresponding relationship curve between the temperature and the actual deformation during the heating process of the bonding carrier; through a multi-segment segmentation compensation algorithm, the reference data is divided into multiple continuous segments of temperature and deformation data, and accurate compensation values ​​​​are obtained for different segments; through the reference bonding position at the reference temperature and the expansion deformation compensation value corresponding to different temperatures in the actual production process, finally the position compensation is performed through the five axes of the upper heating carrier, so as to achieve the same pressing amount at different temperatures during the wafer bonding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic flow chart of the high-temperature deformation self-compensation algorithm for the wafer bonding process of the present invention;

[0014] Figure 2 This is the curve of wafer bonding pressure variation with temperature under the conventional mode of the existing technology;

[0015] Figure 3 It is the temperature deformation slope curve of the segmented temperature range of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the solutions in the embodiments of the present invention are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0017] It should be noted that the embodiments of the present invention and the features therein may be combined with each other as long as there is no conflict between the combinations.

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention. Figure 1 As shown, a high-temperature deformation self-compensation algorithm for a wafer bonding process includes:

[0019] Step S1, repeatedly heating the wafer carrier to stabilize the material properties, and then using a tool to measure the deformation of the wafer carrier at different temperatures during the heating process;

[0020] Step S2: constructing a temperature deformation curve showing deformation as a function of temperature based on the above-mentioned measured quantities; Step S3: dividing the temperature deformation curve into multiple continuous temperature interval deformation slopes. The finer the division, the higher the accuracy. Independent compensation calculation is performed within each data interval.

[0021] Step S4: During the wafer bonding pressurization process, the actual temperature of the wafer carrier is detected in real time, the temperature range to which the actual temperature belongs is found, and the corresponding wafer carrier expansion deformation compensation value Pos is calculated, Pos=H 基准 -H n -(H n+1 -H n ) / (C n+1 -C n )*(C 当前 -C n );

[0022] Among them H 基准 Indicates the type variable at room temperature, H n Indicates the starting deformation value of the current temperature range, C n Indicates the starting temperature of the current temperature range, H n+1 Indicates the starting deformation value of the next temperature range, C n+1 Indicates the starting temperature of the next temperature interval, C 当前 Indicates the current temperature value;

[0023] In step S5 , the control system controls the pressing device to perform corresponding pressing amount deformation compensation, so that the predetermined pressing amount is always maintained during the wafer carrier temperature rising process.

[0024] The present invention uses multi-point sampling to determine the correspondence between temperature and actual deformation during the heating process of the bonding carrier. A multi-segment segmentation compensation algorithm segments the reference data into multiple continuous segments of temperature and deformation data. This allows for accurate compensation values ​​to be derived for each segment. The reference bonding position at the reference temperature is used to determine expansion compensation values ​​corresponding to different temperatures during actual production. Position compensation is performed on the five axes of the upper heated carrier, ensuring consistent penetration at different temperatures during wafer bonding. Precise trajectory control ensures the quality and stability of product production and processing.

[0025] It should be noted that according to the number of pressing rods of the pressing device, the temperature and deformation data of multiple pressing points of the wafer carrier can be detected simultaneously, and the deformation slope of the temperature range can be calculated respectively, and then the pressing amount can be controlled separately during actual processing.

[0026] While the principal features and advantages of the present invention have been shown and described above, it will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the foregoing description, and all variations that come within the meaning and range of equivalents of the claims are intended to be embraced thereby.

Claims

1. A high temperature deformation self-compensation algorithm for wafer bonding process, characterized in that: The steps include: Step S1, heating the wafer carrier to obtain the deformation amount of the wafer carrier at different temperatures during the heating process; Step S2, constructing a temperature deformation variation curve of the deformation variation with temperature; Step S3, dividing the temperature deformation variation curve into a plurality of continuous temperature interval deformation slopes; Step S4, during the wafer bonding pressurization process, the actual temperature of the wafer carrier is detected in real time, the temperature range to which the actual temperature belongs is found, and the corresponding wafer carrier expansion deformation compensation value Pos is calculated. Pos=H 基准 -H n -(H n+1 -H n ) / (C n+1 -C n )*(Ccurrent-C n ); Among them, H 基准 Indicates the deformation value at room temperature, Hn indicates the initial deformation value of the current temperature range, C n Indicates the starting temperature of the current temperature interval, Hn+1 indicates the starting deformation value of the next temperature interval, C n+1 Indicates the starting temperature of the next temperature interval, C 当前 Indicates the current temperature value; Step S5, the control system controls the pressing device to perform corresponding pressing amount deformation compensation, so that the predetermined pressing amount is always maintained during the wafer carrier temperature rising process.

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