Laser Debonding Step Compensation Method

Abstract

The present invention provides a laser debonding step compensation method, applicable to the debonding process of a stacked structure, wherein the stacked structure includes a substrate and a wafer bonded together with bonding adhesive. During debonding, a transparent suction cup is attached to the substrate. The method comprises: determining a target position based on the previous burst point position and the heat-affected zone of the previous burst point; determining the substrate incident position at the current burst point position based on the target position and the laser optical path of the previous burst point; determining the current compensation displacement of the laser generator based on the thickness and refractive index of the suction cup at the substrate incident position; and controlling the laser generator to move to the laser generator position at the current burst point based on a predetermined first displacement and the compensation displacement. The present invention can compensate for optical path deviation caused by refraction in different thickness regions of the suction cup, thereby accurately positioning the burst point during the laser debonding process.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing, and in particular to a laser debonding step compensation method. Background Art

[0002] In the field of semiconductor manufacturing, it is often necessary to thin the thickness of a single semiconductor wafer. Therefore, the backside of the thick semiconductor wafer must be thinned (grinding and cutting) after loading the integrated circuit. During this process, the semiconductor wafer is usually temporarily bonded to a substrate. The substrate serves as the base of the semiconductor wafer during the processing to protect the semiconductor wafer from damage due to the thinning process. After the semiconductor wafer is thinned, the semiconductor wafer and the substrate must be debonded.

[0003] In the prior art, during the debonding process of a semiconductor wafer and a substrate, the debonding of the semiconductor wafer and the substrate is achieved by dissolving the bonding adhesive with a chemical solvent, by thermal sliding peeling, or by laser debonding. For laser debonding, it is usually necessary to irradiate all the bonding adhesive with a laser to cause a phase change, and then apply force to separate the semiconductor wafer and the substrate. In order to separate the laser-irradiated area as quickly as possible, a transparent suction cup can be attached to the substrate. The laser passes through the transparent suction cup and the substrate to irradiate the bonding adhesive, and then the transparent suction cup is used to apply force to the substrate to separate the substrate and the wafer.

[0004] In the process of realizing the present invention, the inventors found that there are at least the following technical problems in the prior art: different areas of the transparent suction cup usually have different thicknesses, and the laser light path will cause different offsets during the propagation process in areas of different thicknesses, resulting in inaccurate explosion point positions. Summary of the Invention

[0005] The laser debonding step compensation method provided by the present invention can compensate for the optical path deviation caused by refraction of different thickness areas of the suction cup, so that the explosion point position in the laser debonding process can be accurately located.

[0006] The present invention provides a laser debonding step compensation method, which is applied to the debonding process of a stacked structure, wherein the stacked structure includes a substrate and a wafer bonded together with bonding glue. During debonding, a transparent suction cup is used to adsorb on the substrate. The method comprises:

[0007] Determine the target location of the current explosion point based on the location of the previous explosion point and the heat-affected area of ​​the previous explosion point;

[0008] Determining the substrate incident position corresponding to the current burst point position based on the target position and the laser light path corresponding to the previous burst point;

[0009] Determining the compensation displacement of the current laser generator according to the thickness and refractive index of the suction cup corresponding to the incident position of the substrate;

[0010] The laser generator is controlled to move to the laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement, so that the laser emitted by the laser generator is refracted by the transparent suction cup and incident on the target position of the current burst point.

[0011] Optionally, determining the target position of the current explosion point based on the position of the previous explosion point and the heat-affected zone of the previous explosion point includes:

[0012] Dividing the laminate structure into a plurality of debonding regions, wherein the plurality of debonding regions are a plurality of concentrically arranged annular regions, each of the annular regions being capable of accommodating a plurality of heat-affected zones of explosion points;

[0013] The stepping direction and stepping distance of the current burst point are determined according to the position of the previous burst point in the corresponding debonding region.

[0014] Optionally, determining the stepping direction and stepping distance of the current burst point according to the position of the previous burst point in the corresponding debonding region includes:

[0015] When the previous burst point is a burst point other than the last burst point in the current area;

[0016] Determining a first heat-affected range of the heat-affected zone along the circumference of the laminate structure according to the heat-affected zone of the previous explosion point;

[0017] Taking the position of the previous explosion point as a starting point, the first heat-affected range is stepped along the circumference of the stacked structure to determine the target position of the current explosion point.

[0018] Optionally, determining the stepping direction and stepping distance of the current burst point according to the position of the previous burst point in the corresponding debonding region includes:

[0019] When the previous burst point is the last burst point in the current area;

[0020] Determining a second heat-affected range of the heat-affected zone along the radial direction of the laminate structure according to the heat-affected zone of the previous explosion point;

[0021] Taking the position of the previous explosion point as a starting point, the second heat-affected range is stepped radially along the stacked structure to determine the target position of the current explosion point.

[0022] Optionally, determining the current compensation displacement of the laser generator according to the thickness and refractive index of the suction cup corresponding to the incident position of the substrate includes:

[0023] Determining a first propagation direction of the laser corresponding to the current burst point in the substrate according to the optical path of the previous burst point;

[0024] determining a second propagation direction of the laser corresponding to the current burst point in the suction cup according to the propagation direction and the refractive index;

[0025] Determining, based on the second propagation direction, the thickness and the refractive index of the suction cup, an offset distance generated by the laser corresponding to the current burst point during propagation in the suction cup;

[0026] The compensation displacement is determined according to the offset distance.

[0027] Optionally, the suction cup comprises a disk, wherein a plurality of grooves are formed on a surface of one side of the disk, and the grooves are separated by groove ridges;

[0028] Determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes:

[0029] Determining a thickness difference between the channel position and the channel ridge position based on the suction cup thickness at the channel position and the suction cup thickness at the channel ridge position;

[0030] Determining a first distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel according to the second propagation direction, the thickness difference, and the refractive index;

[0031] When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

[0032] Optionally, the suction cup comprises a disk, wherein a plurality of grooves are formed on a surface of one side of the disk, and the grooves are separated by groove ridges;

[0033] Determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes:

[0034] determining an incident point and an exit point of the laser light at the channel ridge according to the second propagation direction;

[0035] Determining the thickness of the chuck through which the laser propagates according to the incident point and the exit point;

[0036] Determining a second distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel according to the second propagation direction, the thickness of the chuck, and the refractive index;

[0037] When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

[0038] Optionally, controlling the laser generator to move to a laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement includes:

[0039] Controlling the laser generator to move uniformly at a first moving speed in a predetermined displacement direction;

[0040] calculating a first movement time according to the first displacement, the compensation displacement, and the first movement speed;

[0041] After the previous burst point is completed, the laser generator is turned on after a first movement time interval, so that the laser generator emits laser light at a laser generator position corresponding to the current burst point.

[0042] Optionally, determining the substrate incident position corresponding to the current burst point position according to the target position and the laser light path corresponding to the previous burst point includes:

[0043] Taking the target position as the starting point, along the transmission direction of the laser light path corresponding to the previous burst point in the substrate, determine the propagation path of the laser light path corresponding to the current burst point in the substrate;

[0044] The substrate incident position is determined according to the intersection of the propagation path and the laser incident surface of the substrate.

[0045] Optionally, the predetermined first displacement is determined as follows:

[0046] The value and direction of the first displacement are determined according to the target position of the current burst point and the position of the previous burst point.

[0047] In the technical solution provided by the present invention, the substrate incident position corresponding to the current flash point and the laser optical path corresponding to the previous flash point are determined by the location of the previous flash point and the heat-affected zone. The optical path of the current flash point and the optical path of the previous flash point are parallel within the substrate. Furthermore, since the optical path is reversible, the optical path before entering the substrate is determined by the transmission portion of the optical path of the previous flash point within the substrate and the substrate incident position. The offset distance of the optical path can be determined based on the angle of the optical path, the refractive index of the suction cup, and the change in the thickness of the suction cup through which the optical path corresponding to the current flash point passes. This offset distance can be used to determine the compensation displacement. When moving the laser generator, the pre-determined first displacement of the laser generator is first superimposed with the compensation displacement to determine the final required movement distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is a flow chart of a laser debonding step compensation method according to an embodiment of the present invention;

[0049] Figure 2 This is a flow chart of determining the current burst point step of a laser debonding step compensation method according to another embodiment of the present invention;

[0050] Figure 3 A flow chart of determining compensation displacement of a laser debonding step compensation method according to another embodiment of the present invention;

[0051] Figure 4 A flow chart of a laser debonding step compensation method according to another embodiment of the present invention, wherein the optical path passes through all the channel ridges;

[0052] Figure 5 A flow chart of a laser debonding step compensation method according to another embodiment of the present invention, wherein the optical path passes through a portion of the channel ridge;

[0053] Figure 6 A flow chart of determining an offset distance in a laser debonding step compensation method according to another embodiment of the present invention;

[0054] Figure 7 A flowchart of determining an offset distance in a laser debonding step compensation method according to another embodiment of the present invention;

[0055] Figure 8 This is a flow chart of determining the explosion point position in a laser debonding step compensation method according to another embodiment of the present invention;

[0056] Figure 9 This is a flow chart of the incident position of a substrate in a laser debonding step compensation method according to another embodiment of the present invention. DETAILED DESCRIPTION

[0057] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments 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 ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0058] The embodiment of the present invention provides a laser debonding step compensation method, such as Figure 1 As shown, in a debonding process of a stacked structure, wherein the stacked structure includes a substrate and a wafer bonded together with a bonding adhesive, a transparent suction cup is used to adsorb on the substrate during debonding, and the method includes:

[0059] Step 100, determining the target position of the current explosion point based on the position of the previous explosion point and the heat affected area of ​​the previous explosion point;

[0060] In some embodiments, when determining the target position of the current explosion point, the interval between the current explosion point position and the previous explosion point position is set to the size of the heat-affected zone in this direction, so that the heat-affected zones of the current explosion point and the previous explosion point can be closely adjacent, which is beneficial to the subsequent separation process.

[0061] Step 200, determining the substrate incident position corresponding to the current burst point position based on the target position and the laser light path corresponding to the previous burst point;

[0062] In some embodiments, a light path parallel to the laser light path corresponding to the previous burst point is used to form a new light path through the target position. At this time, the intersection of the light path and the upper surface of the substrate is the substrate incident position corresponding to the current burst point position.

[0063] Step 300, determining the current compensation displacement of the laser generator according to the thickness and refractive index of the chuck corresponding to the incident position of the substrate;

[0064] In some embodiments, the distance offset by the laser when transmitting in the suction cup is determined based on the thickness and refractive index of the suction cup; at the same time, the distance offset by the laser when transmitting in the air at the same thickness is determined, and the difference between the two distances can be used to determine the compensation displacement of the current laser generator.

[0065] Step 400 , controlling the laser generator to move to the laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement, so that the laser emitted by the laser generator is refracted by the transparent suction cup and incident on the target position of the current burst point.

[0066] In some embodiments, because the laser's initial transmission medium is air and its final transmission medium is within the substrate, the direction of the optical path in air and within the substrate remains unchanged regardless of the laser generator's position. When the suction cup's thickness remains constant, the laser generator's movement distance is proportional to the distance between two adjacent burst points. Therefore, the first displacement can be directly determined based on the distance between the burst points. The compensation displacement is determined using the method described in step 300. Thus, the laser generator's position corresponding to the current burst point can be determined by combining the first and compensation displacements.

[0067] In the technical solution provided in this embodiment, the substrate incident position corresponding to the current flash point and the laser optical path corresponding to the previous flash point are determined using the location of the previous flash point and the heat-affected zone. The optical path of the current flash point and the optical path of the previous flash point are parallel within the substrate. Furthermore, since the optical path is reversible, the optical path before entering the substrate is determined by combining the transmission portion of the optical path of the previous flash point within the substrate and the substrate incident position. The offset distance of the optical path can be determined based on the angle of the optical path, the refractive index of the suction cup, and the change in the thickness of the suction cup traversed by the optical path corresponding to the current flash point. This offset distance can be used to determine the compensation displacement. When moving the laser generator, the pre-determined first displacement of the laser generator is first superimposed with the compensation displacement to determine the final required movement distance.

[0068] As an optional implementation, Figure 2 As shown, in step 100, determining the target position of the current explosion point based on the position of the previous explosion point and the heat affected area of ​​the previous explosion point includes:

[0069] Step 110, dividing the laminate structure into a plurality of debonding regions, wherein the plurality of debonding regions are a plurality of concentrically arranged annular regions, each of which can accommodate a heat-affected zone of a plurality of explosion points;

[0070] In some embodiments, multiple debonding areas are distributed in a ring shape, and each ring area is laser irradiated and then separated. This can avoid the subsequent debonding area causing heat loss in the previous debonding area during the irradiation process, resulting in poor separation effect of the previous debonding area during the force separation process.

[0071] Step 120 : determining the stepping direction and stepping distance of the current burst point according to the position of the previous burst point in the corresponding debonding region.

[0072] In some embodiments, such as the separation method in step 110, the current debonded region can be separated after the current debonded region is completely irradiated. After the current debonded region is separated, the next debonded region can be irradiated. Therefore, each time the stepping direction and distance are determined, it is necessary to determine whether the current debonded region has been irradiated. If irradiation has not been completed, the current debonded region continues to be stepped and irradiated. If irradiation has been completed, the next debonded region is stepped and irradiated.

[0073] As an optional embodiment, in step 120, determining the stepping direction and stepping distance of the current burst point based on the position of the previous burst point in the corresponding debonding region includes:

[0074] When the previous burst point is a burst point other than the last burst point in the current area;

[0075] In some embodiments, when the current burst point is a burst point other than the last burst point in the current region, it indicates that the current debonding region has not yet been irradiated, and therefore, irradiation is still required in the current debonding region.

[0076] Determining a first heat-affected range of the heat-affected zone along the circumference of the laminate structure according to the heat-affected zone of the previous explosion point;

[0077] In some embodiments, the current debonding area can usually accommodate a circle of annularly arranged explosion points. Therefore, in order to determine the position of the current explosion point, the circumferential distribution range of the heat-affected area is determined as the first heat-affected range. When stepping along the first heat-affected range, the heat-affected ranges of adjacent explosion points can be closely adjacent.

[0078] Taking the position of the previous explosion point as a starting point, the first heat-affected range is stepped along the circumference of the stacked structure to determine the target position of the current explosion point.

[0079] In some embodiments, since the explosion point is usually located at the center of the corresponding heat affected range, the heat affected ranges of two adjacent explosion points can be closely adjacent and not overlapped by taking the position of the previous explosion point as the starting point and the first heat affected range as the stepping distance.

[0080] As an optional embodiment, in step 120, determining the stepping direction and stepping distance of the current burst point based on the position of the previous burst point in the corresponding debonding region includes:

[0081] When the previous burst point is the last burst point in the current area;

[0082] In some embodiments, when the previous burst point is the last burst point in the current region, it indicates that the current debonding region has been completely irradiated, and force can be applied to the current debonding region to separate it. When the burst point is confirmed, stepping should be performed radially to step to the next debonding region.

[0083] Determining a second heat-affected range of the heat-affected zone along the radial direction of the laminate structure according to the heat-affected zone of the previous explosion point;

[0084] In some embodiments, due to the different laser shapes and movement directions, the heat affected area of ​​the explosion point usually has different heat affected ranges in the circumferential and radial directions. Therefore, the range of the heat affected area distributed radially along the laminate structure is the second heat affected range.

[0085] Taking the position of the previous explosion point as a starting point, the second heat-affected range is stepped radially along the stacked structure to determine the target position of the current explosion point.

[0086] In some embodiments, before or during stepping, the debonded area that has just been irradiated should be forcefully separated. During stepping, the second heat-affected zone is used as the stepping point, and the previous explosion point is used as the starting point, so that two adjacent debonded areas are closely adjacent and do not overlap.

[0087] As an optional implementation, Figure 3 As shown, in step 300, determining the compensation displacement of the current laser generator according to the thickness and refractive index of the suction cup corresponding to the incident position of the substrate includes:

[0088] Step 310, determining a first propagation direction of the laser corresponding to the current burst point in the substrate based on the optical path of the previous burst point;

[0089] In some embodiments, the light paths corresponding to each flash point have consistent directions before entering the transparent suction cup and after entering the substrate. The factor influencing the flash point location is the path the light path takes within the transparent suction cup. Therefore, in this step, the propagation direction of the light path corresponding to the current flash point within the substrate can be determined based on the light path of the previous flash point. Flash point locations are typically evenly spaced, and the spacing is typically pre-determined, for example, based on the size of the corresponding heat-affected zone. Furthermore, because light paths are reversible, the light path corresponding to the current flash point can be determined in reverse, using the current flash point location as a base point and the light path's propagation direction within the substrate as a guide.

[0090] Step 320: determining a second propagation direction of the laser corresponding to the current burst point in the chuck based on the propagation direction and the refractive index;

[0091] In some embodiments, as Figure 4 As shown, the light path corresponding to the leftmost burst point passes through the channel ridge of the transparent chuck, requiring calculation of its offset distance. Because the light path propagates through the transparent chuck before entering the substrate, the refractive index between the transparent chuck and the substrate can be used to determine its propagation direction within the transparent chuck.

[0092] Step 330: Determine the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index;

[0093] In some embodiments, the light path is determined by taking the incident point of the light path on the substrate as the base point and the second propagation direction as the direction. Furthermore, based on the change in the thickness c of the chuck and the refractive index of the chuck relative to air, the offset distance caused by the propagation path relative to propagation in air can be calculated. Figure 4As shown, before the explosion point hits the suction cup, the angle with the normal is N1, and after it hits the substrate, the angle with the normal is N3, and after it hits the suction cup, the angle with the normal is N2. Obviously, Figure 4 In the figure, when irradiating from right to left, the explosion point on the far left is affected by the transmission of the suction cup material with a thickness of C, causing its position to shift, and its offset distance can be calculated as follows: ba = c (tanN1-tanN2), where ba is the offset distance.

[0094] Step 340: Determine the compensation displacement according to the offset distance.

[0095] In some embodiments, the offset distance is the optical path offset caused by the light path transmitting in a transparent suction cup with a thickness of c. Therefore, the offset distance can be used as a compensation displacement to pre-compensate the position of the laser generator. Thus, when the optical path is offset, the explosion point position generated is exactly the target explosion point position.

[0096] As an optional implementation, Figure 6 As shown, the suction cup includes a disc, wherein a plurality of grooves are formed on a surface of one side of the disc, and the grooves are separated by groove ridges;

[0097] In step 330, determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes:

[0098] Step 331, determining a thickness difference between the channel position and the channel ridge position based on the suction cup thickness at the channel position and the suction cup thickness at the channel ridge position;

[0099] In some embodiments, the position that needs to be compensated is usually when stepping from the channel position of the suction cup to the channel ridge position of the suction cup. Due to the difference in thickness between the channel ridge and the channel, the optical path transmission is offset. Therefore, the thickness difference between the channel position and the channel ridge position can be calculated first to facilitate the subsequent calculation of the offset distance.

[0100] Step 332, determining a first distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel according to the second propagation direction, the thickness difference, and the refractive index;

[0101] In some embodiments, when the light propagation path passes through a complete channel ridge, the thickness difference calculated in step 331 is used as the parameter c in the calculation formula in step 330 to calculate the offset distance.

[0102] Step 333: When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

[0103] In some embodiments, whether the position of the laser generator needs to be compensated is determined based on the path of the light path. When the light path passes through the channel ridge, compensation is required, and the first distance is used as the offset distance for compensation. When the light path passes through the channel, no compensation is required.

[0104] As an optional implementation, Figure 7 As shown, the suction cup includes a disc, wherein a plurality of grooves are formed on a surface of one side of the disc, and the grooves are separated by groove ridges;

[0105] In step 330, determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes:

[0106] Step 334, determining the incident point and the exit point of the laser on the channel ridge according to the second propagation direction;

[0107] In some embodiments, as Figure 5 As shown, when the laser light path passes through only a portion of the channel ridge height, since only the channel ridge height that the light path passes through will affect the offset distance of the light path, it is necessary to determine the incident point and the exit point of the laser on the channel ridge portion.

[0108] Step 335, determining the thickness of the chuck through which the laser propagates based on the incident point and the exit point;

[0109] In some embodiments, the thickness of the chuck through which the laser passes during propagation is calculated based on the vertical height difference between the incident point and the exit point.

[0110] Step 336, determining a second distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel based on the second propagation direction, the thickness of the chuck, and the refractive index;

[0111] In some embodiments, as Figure 5 The offset distance of c shown can be determined by calculating according to the calculation formula in step 330.

[0112] Step 337 : When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

[0113] In some embodiments, when the laser light path corresponding to the current burst point passes through a portion of the channel ridge, the corresponding offset distance is determined for compensation, while when the laser light path does not pass through the channel ridge, no compensation is required.

[0114] As an optional implementation, Figure 8 As shown, in step 400, controlling the laser generator to move to the laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement includes:

[0115] Step 410, controlling the laser generator to move uniformly at a first moving speed in a predetermined displacement direction;

[0116] In some embodiments, the displacement direction is determined according to the discharge direction of the plurality of debonded regions, and the first movement speed is a predetermined movement speed, which is generally related to parameters such as the power and energy of the laser.

[0117] Step 420, calculating a first moving time according to the first displacement, the compensation displacement, and the first moving speed;

[0118] In some embodiments, the distance between the positions of the laser generators corresponding to two adjacent burst points is determined based on the first displacement and the compensation displacement, and the time required for the laser generator to move the corresponding distance can be calculated based on the first moving speed.

[0119] Step 430 : After the previous burst point is completed, the laser generator is turned on after a first movement time interval, so that the laser generator emits laser light at the laser generator position corresponding to the current burst point.

[0120] In some embodiments, the laser generator is kept in constant motion, and the location of the blast point is controlled by turning it on and off. This approach, because the laser generator is always in motion, can save considerable time and improve debonding efficiency.

[0121] As an optional implementation, Figure 9 As shown, in step 200, determining the substrate incident position corresponding to the current burst point position based on the target position and the laser light path corresponding to the previous burst point includes:

[0122] Step 210, starting from the target position, and following the transmission direction of the laser light path corresponding to the previous burst point in the substrate, determine the propagation path of the laser light path corresponding to the current burst point in the substrate;

[0123] In some embodiments, the target location is the location that the optical path corresponding to the current burst point must pass through. Furthermore, since the transmission directions of the laser optical paths corresponding to each burst point in the substrate are parallel, the transmission direction of the laser optical path corresponding to the previous burst point in the substrate is used as the transmission direction of the laser optical path corresponding to the current burst point in the substrate. Once the points and directions of the optical path are determined, a unique optical path can be determined.

[0124] Step 220 : determining the substrate incident position according to the intersection of the propagation path and the laser incident surface of the substrate.

[0125] In some embodiments, the incident position of the substrate can be determined by the intersection of the light path determined in step 210 and the incident surface of the substrate.

[0126] As an optional implementation manner, the predetermined first displacement is determined as follows:

[0127] The value and direction of the first displacement are determined according to the target position of the current burst point and the position of the previous burst point.

[0128] In some embodiments, the Figure 4 and attached Figure 5 As shown in the optical path diagram, when the optical path does not pass through the channel ridge, the distance the laser generator moves is generally the same as the distance the burst point moves. Therefore, the distance and direction of the laser generator's movement can be determined based on the direction and distance relationship between adjacent burst points.

[0129] Those skilled in the art will appreciate that all or part of the processes in the above method embodiments can be implemented by instructing related hardware through a computer program. The program can be stored in a computer-readable storage medium, and when executed, the program can include the processes in the above method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0130] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A laser debonding step compensation method, characterized in that: The method is applied to a debonding process of a stacked structure, wherein the stacked structure includes a substrate and a wafer bonded together with a bonding adhesive. During debonding, a transparent suction cup is used to adsorb on the substrate. The method comprises: Determine the target location of the current explosion point based on the location of the previous explosion point and the heat-affected area of ​​the previous explosion point; Determining the substrate incident position corresponding to the current burst point position based on the target position and the laser light path corresponding to the previous burst point; Determining the compensation displacement of the current laser generator according to the thickness and refractive index of the suction cup corresponding to the incident position of the substrate; Controlling the laser generator to move to the laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement, so that the laser light emitted by the laser generator is refracted by the transparent suction cup and incident on the target position of the current burst point; Wherein, determining the compensation displacement of the current laser generator according to the thickness and refractive index of the suction cup corresponding to the incident position of the substrate includes: Determining a first propagation direction of the laser corresponding to the current burst point in the substrate according to the optical path of the previous burst point; determining a second propagation direction of the laser corresponding to the current burst point in the chuck according to the first propagation direction and the refractive index; Determining, based on the second propagation direction, the thickness and the refractive index of the suction cup, an offset distance generated by the laser corresponding to the current burst point during propagation in the suction cup; The compensation displacement is determined according to the offset distance.

2. The laser debonding step compensation method according to claim 1, wherein: Based on the location of the previous explosion point and the heat affected area of ​​the previous explosion point, the target location of the current explosion point is determined including: Dividing the laminate structure into a plurality of debonding regions, wherein the plurality of debonding regions are a plurality of concentrically arranged annular regions, each of the annular regions being capable of accommodating a plurality of heat-affected zones of explosion points; The stepping direction and stepping distance of the current burst point are determined according to the position of the previous burst point in the corresponding debonding region.

3. The laser debonding step compensation method according to claim 2, wherein: Determining the stepping direction and stepping distance of the current burst point based on the position of the previous burst point in the corresponding debonding region includes: When the previous burst point is a burst point other than the last burst point in the current area; Determining a first heat-affected range of the heat-affected zone along the circumference of the laminate structure according to the heat-affected zone of the previous explosion point; Taking the position of the previous explosion point as a starting point, the first heat-affected range is stepped along the circumference of the stacked structure to determine the target position of the current explosion point.

4. The laser debonding step compensation method according to claim 2, wherein: Determining the stepping direction and stepping distance of the current burst point based on the position of the previous burst point in the corresponding debonding region includes: When the previous burst point is the last burst point in the current area; Determining a second heat-affected range of the heat-affected zone along the radial direction of the laminate structure according to the heat-affected zone of the previous explosion point; Taking the position of the previous explosion point as a starting point, the second heat-affected range is stepped radially along the stacked structure to determine the target position of the current explosion point.

5. The laser debonding step compensation method according to claim 1, wherein: The suction cup comprises a disk, wherein a plurality of grooves are formed on a surface of one side of the disk, and the grooves are separated by groove ridges; Determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes: Determining a thickness difference between the channel position and the channel ridge position based on the suction cup thickness at the channel position and the suction cup thickness at the channel ridge position; Determining a first distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel according to the second propagation direction, the thickness difference, and the refractive index; When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

6. The laser debonding step compensation method according to claim 5, wherein: The suction cup comprises a disk, wherein a plurality of grooves are formed on a surface of one side of the disk, and the grooves are separated by groove ridges; Determining the offset distance generated by the laser corresponding to the current burst point during propagation in the chuck according to the second propagation direction, the thickness of the chuck, and the refractive index includes: determining an incident point and an exit point of the laser light at the channel ridge according to the second propagation direction; Determining the thickness of the chuck through which the laser propagates according to the incident point and the exit point; Determining a second distance by which the laser light passing through the channel ridge is offset relative to the laser light passing through the channel according to the second propagation direction, the thickness of the chuck, and the refractive index; When the laser corresponding to the current burst point passes through the channel ridge, the first distance is used as the offset distance. When the laser corresponding to the current burst point passes through the channel, the offset distance is determined to be 0.

7. The laser debonding step compensation method according to claim 1, wherein: Controlling the laser generator to move to a laser generator position corresponding to the current burst point according to the predetermined first displacement and the compensation displacement includes: Controlling the laser generator to move uniformly at a first moving speed in a predetermined displacement direction; calculating a first movement time according to the first displacement, the compensation displacement, and the first movement speed; After the previous burst point is completed, the laser generator is turned on after a first movement time interval, so that the laser generator emits laser light at a laser generator position corresponding to the current burst point.

8. The laser debonding step compensation method according to claim 1, wherein: Determining the substrate incident position corresponding to the current burst point position based on the target position and the laser light path corresponding to the previous burst point includes: Taking the target position as the starting point, along the transmission direction of the laser light path corresponding to the previous burst point in the substrate, determine the propagation path of the laser light path corresponding to the current burst point in the substrate; The substrate incident position is determined according to the intersection of the propagation path and the laser incident surface of the substrate.

9. The laser debonding step compensation method according to claim 1, wherein: The process of determining the predetermined first displacement is as follows: The value and direction of the first displacement are determined according to the target position of the current burst point and the position of the previous burst point.

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