Multilayer laser de-bonding method

Abstract

The invention discloses a multilayer laser de-bonding method. The method comprises the following steps: acquiring parameter information of a to-be-de-bonded piece; acquiring a parameter comparison table, and acquiring corresponding laser energy and de-bonding times in the parameter comparison table according to the parameter information of the to-be-de-bonded piece; determining a de-bonding area of the to-be-de-bonded piece; controlling a laser beam to perform multi-layer scanning on the de-bonding area according to the corresponding laser energy and the de-bonding times so as to remove bonding; therefore, according to the parameter information of the to-be-de-bonded piece, the preset laser energy and the de-bonding times corresponding to the to-be-de-bonded piece are obtained, and the de-bonding area is subjected to de-bonding times scanning by controlling the laser beam with the laser energy, so that the bonding is removed, and the crack rate of the cavity film structure is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor chip manufacturing, and particularly to a multi-layer laser debonding method. Background Art

[0002] In the process routes of ultra-thin wafers and complex packages, due to the thin thickness of the wafers and the need for multiple etching, polishing, cleaning, etc. when processing various circuits on the wafers, the wafers are usually temporarily bonded to the substrates before processing, and then the wafers are processed on the surface; after the wafer processing is completed, the wafers and the substrates need to be debonded so that the wafers and the substrates are separated; currently, in the process of debonding the wafers and the substrates, the laser debonding method is usually used to release the laser response layer at one time through laser energy. Currently, laser debonding is mainly applied to three-dimensional integrated structures, and the bottom layer is mainly made of materials such as photoresist and dry film; however, in the application of the cavity thin film structure at the bottom layer, due to the laser response layer being released at one time, the chemical force impacts the cavity thin film, resulting in frequent film cracking abnormalities. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems in the above technologies to some extent. For this reason, an object of the present invention is to propose a multi-layer laser debonding method, which obtains the corresponding laser energy and debonding times through the parameter information of the workpiece to be debonded, so as to perform multi-layer scanning on the debonding area, thereby greatly improving the crack rate of the cavity thin film structure.

[0004] To achieve the above object, an embodiment of the present invention proposes a multi-layer laser debonding method, which is applied to a workpiece to be debonded having a cavity structure. The multi-layer laser debonding method includes obtaining the parameter information of the workpiece to be debonded; obtaining a parameter comparison table, and obtaining the corresponding laser energy and debonding times in the parameter comparison table according to the parameter information of the workpiece to be debonded; determining the debonding area of the workpiece to be debonded; and controlling a laser beam to perform multi-layer scanning on the debonding area according to the corresponding laser energy and debonding times to release the bond.

[0005] According to the multi-layer laser debonding method of the embodiment of the present invention, the preset corresponding laser energy and debonding times are obtained according to the parameter information of the workpiece to be debonded, and the bond is released by controlling the laser beam with the laser energy to scan the debonding area for the debonding times, thereby greatly improving the crack rate of the cavity thin film structure.

[0006] In addition, the multi-layer laser debonding method proposed according to the above embodiment of the present invention may further have the following additional technical features:

[0007] Optionally, obtain a parameter comparison table, including: obtaining the first laser energy corresponding to the bonding part to be disassembled; adjusting the first laser energy, and controlling the laser beam to perform multiple repeated laser scans on the disbonding area of the bonding part to be disassembled for different times, so as to record the probability of cracks appearing in the cavity thin film after multiple laser scans of different times; after performing multiple laser energy adjustments and multiple laser scans of different times, obtain the second laser energy and the disbonding times corresponding to the lowest probability of cracks appearing in the cavity thin film of the bonding part to be disassembled; and so on, record the second laser energy and the disbonding times corresponding to multiple different bonding parts to be disassembled, so as to obtain the parameter comparison table.

[0008] Optionally, the second laser energy is less than the first laser energy.

[0009] Optionally, the bonding part to be disassembled includes a first layer structure and a second layer structure bonded through a bonding layer, and the bonding part to be disassembled is placed on a laser disbonding machine table.

[0010] Optionally, the bonding layer includes a laser-responsive layer and a temporary bonding adhesive layer, and the laser-responsive layer is disposed on the temporary bonding adhesive layer.

[0011] Optionally, the parameter information of the bonding part to be disassembled includes the material information of the laser-responsive layer corresponding to the bonding part to be disassembled.

[0012] Optionally, the second layer structure is a cavity structure, the second layer structure is in contact with the laser disbonding machine table, and has a thin film layer.

[0013] Optionally, determining the disbonding area of the bonding part to be disassembled includes: measuring the distance from the lens to the surface of the first layer structure by using an optical ranging system on the laser disbonding machine table; determining the position of the laser-responsive layer according to the distance from the lens to the surface of the first layer structure; and controlling the automatic focusing laser on the laser disbonding machine table to automatically adjust the focal position of the laser beam according to the position of the laser-responsive layer, so as to focus on the laser-responsive layer.

[0014] Optionally, measuring the distance from the lens to the surface of the first layer by using an optical ranging system on the laser disbonding machine table includes: the optical ranging system emits a beam of laser to the surface of the first layer structure; the laser is reflected back to the optical ranging system, so as to obtain the distance from the lens to the surface of the first layer structure by measuring the propagation time or phase change of the reflected light.

[0015] Optionally, determining the position of the laser-responsive layer according to the distance from the lens to the surface of the first layer structure includes: obtaining the thickness of the first layer structure; and obtaining the position of the laser-responsive layer according to the distance from the lens to the surface of the first layer structure and the thickness of the first layer structure. Description of the Drawings

[0016] Figure 1 is a schematic flow chart of a multi-layer laser debonding method according to an embodiment of the present invention;

[0017] Figure 2 is a schematic structural diagram of a component to be debonded according to an embodiment of the present invention;

[0018] Figure 3 is a schematic diagram of a laser debonding machine according to an embodiment of the present invention. Detailed implementation manners

[0019] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] In order to better understand the above technical solution, the exemplary embodiments of the present invention will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be fully conveyed to those skilled in the art.

[0021] In order to better understand the above technical solution, the above technical solution will be described in detail below in combination with the specification drawings and specific implementation manners.

[0022] Figure 1 is a schematic flow chart of a multi-layer laser debonding method according to an embodiment of the present invention. The multi-layer laser debonding method is applied to a component to be debonded having a cavity structure; as Figure 1 shown, the multi-layer laser debonding method according to the embodiment of the present invention includes the following steps:

[0023] S101, obtaining parameter information of the component to be debonded.

[0024] It should be noted that the parameter information of the component to be debonded includes material information of the laser response layer corresponding to the component to be debonded.

[0025] S102, obtaining a parameter comparison table, and obtaining the corresponding laser energy and debonding times in the parameter comparison table according to the parameter information of the component to be debonded.

[0026] That is to say, the parameter comparison table includes a plurality of different laser response layer materials, and the laser energy and debonding times corresponding to each different laser response layer material.

[0027] As an embodiment, obtain a parameter comparison table, including: obtaining the first laser energy corresponding to the bonding part to be solved; adjusting the first laser energy, and controlling the laser beam to perform multiple repeated laser scans on the debonding area of the bonding part to be solved for different times, so as to record the probability of cracks appearing in the cavity film after multiple laser scans of different times; after performing multiple laser energy adjustments and multiple laser scans of different times, obtain the second laser energy and the debonding times corresponding to the cavity film with the lowest probability of cracks appearing in the bonding part to be solved; and so on, record the second laser energy and the debonding times corresponding to multiple different bonding parts to be solved, so as to obtain a parameter comparison table.

[0028] It should be noted that there is a preset first laser energy corresponding to the laser response layer material in each bonding part to be solved. If the first laser energy is directly sampled and a single laser scan is performed on the laser response layer, it is easy to cause chemical force to impact the cavity film, resulting in abnormal cracks. Therefore, it is necessary to set the corresponding second laser energy and debonding times according to different laser response layer materials for hierarchical laser debonding.

[0029] In addition, since the lower the laser energy, the greater the difficulty of debonding, and the corresponding number of debonding times will be more, it is necessary to balance the laser energy and the debonding times. Therefore, multiple suitable combinations of laser energy and debonding times are selected for fixed multiple tests to record their crack rates. Among them, the selected laser energy needs to be less than the first laser energy.

[0030] As one specific embodiment, assume that the first laser energy is P. First, select the second laser energy to be P - n and the debonding times to be x, perform x times of laser debonding, and record the debonding crack of 60% after repeating the test m times; then adjust the second laser energy to P - n - n and the debonding times to be x + n, perform x + n times of laser debonding, and record the debonding crack of 30% after repeating the test m times. Then, adjust the second laser energy to P - n - n - s and the debonding times to be x + n + s, perform x + n + s times of laser debonding, and record the debonding crack of 0% after repeating the test m times. Then, take the second laser energy of P - n - n - s and the debonding times of x + n + s as the final optimal result and record it in the parameter comparison table; and so on. After multiple groups of selections and multiple tests, the optimal second laser energy and debonding times are obtained.

[0031] In addition, as Figures 2-3As shown, the bonding part to be released 100 includes a first layer structure 10 and a second layer structure bonded by a bonding layer. The bonding part to be released is placed on a laser debonding machine 200. The bonding layer includes a laser-responsive layer 201 and a temporary bonding adhesive layer 202. The laser-responsive layer 201 is disposed on the temporary bonding adhesive layer 202. The second layer structure is a cavity structure. The second layer structure is in contact with the laser debonding machine and has a thin film layer 301.

[0032] That is to say, when performing debonding, the bonding part to be released 100 needs to be placed on the laser debonding machine 200 first, and the second layer structure is in contact with the laser debonding machine 200. Among them, the first layer structure 10 is glass, and the thickness of the thin film layer 301 is 200 - 2000 nm.

[0033] S103, determine the debonding area of the bonding part to be released.

[0034] It should be noted that as Figure 3 shown, the laser debonding machine is equipped with an optical ranging system 40 and an automatic focusing laser system 50 to automatically complete distance measurement and focusing on a fixed point, so as to achieve ranging and focusing at the 0.1 um level.

[0035] As an embodiment, determining the debonding area of the bonding part to be released includes: measuring the distance from the lens to the surface of the first layer structure by using the optical ranging system on the laser debonding machine; determining the position of the laser-responsive layer according to the distance from the lens to the surface of the first layer structure; controlling the automatic focusing laser on the laser debonding machine to automatically adjust the focal position of the laser beam according to the position of the laser-responsive layer so as to focus on the laser-responsive layer.

[0036] As a specific embodiment, the laser debonding machine is equipped with an automatic focusing system, which usually includes adjustable optical elements (such as variable focal length lenses) and a driving motor; after determining the position of the laser-responsive layer, the control system sends an instruction to the automatic focusing system, and the driving motor adjusts the variable focal length lens to make the laser focus accurately align with the laser-responsive layer. The focusing system ensures the accuracy of the focal position through a feedback mechanism (such as a position sensor).

[0037] Specifically, measuring the distance from the lens to the surface of the first layer by using the optical ranging system on the laser debonding machine includes: the optical ranging system emits a beam of laser to the surface of the first layer structure; the laser is reflected back to the optical ranging system to obtain the distance from the lens to the surface of the first layer structure by measuring the propagation time or phase change of the reflected light.

[0038] It should be noted that using a high-precision optical ranging system, such as a laser rangefinder or a confocal ranging system, to measure the distance from the lens to the glass surface can usually achieve an accuracy of 0.1 micron or even higher.

[0039] Specifically, determining the position of the laser response layer according to the distance from the lens to the surface of the first-layer structure includes: obtaining the thickness of the first-layer structure; obtaining the position of the laser response layer based on the distance from the lens to the surface of the first-layer structure and the thickness of the first-layer structure.

[0040] It should be noted that since the laser response layer is arranged below the first-layer structure, it is only necessary to know the distance from the lens to the surface of the first-layer structure and the thickness of the first-layer structure to know the distance from the lens to the laser response layer, so as to accurately locate the position of the laser response layer.

[0041] S104, controlling the laser beam to perform multi-layer scanning on the debonding region according to the corresponding laser energy and the number of debonding times to release the bond.

[0042] That is to say, after obtaining the corresponding laser energy and the number of debonding times, control the laser system to generate a laser beam with the corresponding laser energy, and perform multi-layer scanning on the debonding region according to the number of debonding times, so that the laser response layer is heated to undergo a phase change decomposition, and the bonding between the bonding layer and the first-layer structure and the second-layer structure is released; after the laser scans the laser response layer region, a pulling force can also be applied to the first-layer structure and the second-layer structure to separate the two layer structures.

[0043] In summary, according to the multi-layer laser debonding method of the embodiments of the present invention, first, obtain the parameter information of the component to be debonded; then, obtain the parameter comparison table, and obtain the corresponding laser energy and the number of debonding times in the parameter comparison table according to the parameter information of the component to be debonded; next, determine the debonding region of the component to be debonded; finally, control the laser beam to perform multi-layer scanning on the debonding region according to the corresponding laser energy and the number of debonding times to release the bond; thus, obtain the preset corresponding laser energy and the number of debonding times according to the parameter information of the component to be debonded, and perform scanning of the number of debonding times on the debonding region by controlling the laser beam with this laser energy to release the bond, thereby greatly improving the crack rate of the cavity thin film structure.

[0044] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0045] The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each flow and / or block in the flowchart illustrations and / or block diagrams, and combinations of flows and / or blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processors of a general purpose computer, special purpose computer, embedded processor or other programmable data processing apparatus to produce a machine, such that the instructions executed by the processors of the computer or other programmable data processing apparatus create means for implementing the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in one flow or multiple flows and / or blocks Figure 1 or in one block or multiple blocks.

[0046] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in one flow or multiple flows and / or blocks Figure 1 or in one block or multiple blocks.

[0047] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus, such that a series of operational steps are performed on the computer or other programmable apparatus to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and / or block or blocks. Figure 1 in one flow or multiple flows and / or blocks Figure 1 or in one block or multiple blocks.

[0048] It should be noted that, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims listing several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not denote any order. These words may be interpreted as names.

[0049] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made by those skilled in the art once they learn of the basic inventive concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0050] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

[0051] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0052] In the present invention, unless otherwise clearly defined and limited, the terms such as "mounted", "connected", "connected to", "fixed" and the like should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal connection of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0054] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0055] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A multi-layer laser debonding method, characterized in that, Applied to the bonding part to be debonded with a cavity structure, the multi-layer laser debonding method includes the following steps: Obtain the parameter information of the bonding part to be debonded; Obtain a parameter comparison table, and obtain the corresponding laser energy and debonding times in the parameter comparison table according to the parameter information of the bonding part to be debonded; Determine the debonding area of the bonding part to be debonded; Control the laser beam to perform multi-layer scanning on the debonding area according to the corresponding laser energy and debonding times to release the bond.

2. The multi-layer laser debonding method according to claim 1, wherein Obtain a parameter comparison table, including: Obtain the first laser energy corresponding to the bonding part to be debonded; Adjust the first laser energy, and control the laser beam to perform multiple repeated laser scans on the debonding area of the bonding part to be debonded for different times to record the probability of the cavity film cracking after multiple laser scans of different times; After performing multiple laser energy adjustments and multiple laser scans of different times, obtain the second laser energy and debonding times corresponding to the cavity film of the bonding part to be debonded with the lowest cracking probability; [[ID= 3. The multi-layer laser debonding method according to claim 2, wherein, ​ 4. The multi-layer laser debonding method according to claim 1, characterized in that, ​ 5. The multi-layer laser debonding method according to claim 4, wherein, ​ 6. The multi-layer laser debonding method according to claim 5, wherein, ​ 7. The multi-layer laser debonding method according to claim 4, characterized in that, ​ 8. The multi-layer laser debonding method according to claim 5, wherein, ​ ​ ​ ​ 9. The multi-layer laser debonding method according to claim 8, wherein ​ ​ ​ 10. The multi-layer laser debonding method according to claim 9, wherein ​ ​ ​

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