CN113838777A

CN113838777A - Laser bonding-breaking detection control system

Info

Publication number: CN113838777A
Application number: CN202111035717.6A
Authority: CN
Inventors: 张紫辰; 李纪东; 侯煜; 张昆鹏; 张喆; 张彪; 易飞跃; 杨顺凯
Original assignee: Beijing Zhongke Leite Electronics Co ltd
Current assignee: Beijing Zhongke Leite Electronics Co ltd
Priority date: 2021-09-03
Filing date: 2021-09-03
Publication date: 2021-12-24
Anticipated expiration: 2041-09-03
Also published as: CN113838777B

Abstract

The invention provides a detection control system for laser de-bonding, which is characterized in that in the laser de-bonding process, a sucker is adsorbed on the surface of a substrate, a laser beam sequentially penetrates through the sucker and the substrate and then focuses on a bonding layer, the focus of the laser beam is controlled to be behind a unit area of a scanning part of the bonding layer, the sucker is pulled upwards through a lifting assembly, the substrate and a wafer are separated at the position of the unit area, and the substrate and the wafer are prevented from being bonded again due to the fact that a bonding material in a molten state is cooled and solidified again by adopting a stripping mode that the sucker is pulled for separation while laser de-bonding, so that the stripping difficulty is reduced. And still through setting up half reflection half mirror, detection light source, beam splitter prism, facula detection subassembly and host computer to observe laser facula positional information in real time, bonding layer of local area is heated the condition information, and the host computer is convenient for control the mirror system that shakes adjusts the scanning orbit and the scanning time of laser beam, improves laser and separates bonding efficiency and effect.

Description

Laser bonding-breaking detection control system

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to a laser bonding-breaking detection control system.

Background

During the fabrication of chips, a large number of microelectronic devices are typically fabricated on a wafer by etching, deposition, polishing, etc. Wafers are thin slices cut from a single crystal silicon ingot, typically between 0.3mm and 0.9mm thick, and are seen to be very thin. Since the thickness of a wafer is thin and a plurality of etching, polishing, cleaning, etc. are required when various circuits are processed on the wafer, the wafer is temporarily bonded to a substrate before the processing. And then carrying out deposition, etching and other processes on the surface of the wafer so as to manufacture various microelectronic devices on the surface of the wafer. After the wafer processing is completed, the wafer and the substrate need to be debonded to separate the wafer and the substrate, so that the subsequent wafer scribing process can be performed.

In the prior art, a laser debonding mode is generally adopted in the debonding process of the wafer and the substrate. Specifically, a laser beam is focused on a bonding layer between a wafer and a substrate, and the bonding layer is scanned to heat the bonding layer, so that the bonding layer is in a molten state. After scanning the entire bonding layer, laser heating was stopped, and the wafer and the substrate were peeled off using a transfer device having a suction cup. However, after the laser stops heating, in the process of absorbing the wafer by the suction cup, operations such as moving and absorbing are needed, which takes a long time, and since the laser stops heating, a temperature drop phenomenon inevitably occurs between the wafer and the substrate, so that the bonding material in a molten state is easily cooled and solidified again, and the wafer and the substrate are adhered together again, which increases the difficulty in peeling. In the prior art, the focus of a laser beam is scanned on the whole bonding layer only by controlling a galvanometer system, the laser beam moves only according to an initially set scanning track, and a sucker is adopted to adsorb a substrate for separation after the movement is finished. In the process, the position of a light spot when the bonding layer is scanned by laser, the heating degree of the bonding layer and the like cannot be observed, so that the growth condition of a laser explosion point and energy information of a laser beam cannot be known, and the laser bonding removal effect is poor.

Disclosure of Invention

The invention provides a laser de-bonding detection control system, which is used for reducing the stripping difficulty between a wafer and a substrate in the laser de-bonding process, simultaneously knowing the position information of laser spots and the heating condition information of a bonding layer in a local area in real time, facilitating the adjustment of the scanning track and the scanning time of a laser beam and improving the laser de-bonding efficiency and effect.

The invention provides a detection control system for laser bonding removal, which comprises an objective table, wherein the objective table is used for holding a piece to be bonded removal on the objective table, the piece to be bonded removal comprises a wafer fixed on the surface of the objective table, and a substrate bonded through a bonding layer. The device is also provided with a sucker adsorbed on the surface of the substrate and a lifting assembly connected with the sucker, wherein the lifting assembly is used for pulling the sucker upwards. The laser device is also provided with a laser for generating laser beams and a galvanometer system, wherein the light inlet of the galvanometer system is opposite to the laser device. And a semi-reflecting and semi-transparent mirror is also arranged between the laser and the light inlet of the vibrating mirror system, and laser beams generated by the laser can enter the light inlet of the vibrating mirror system after penetrating through the semi-reflecting and semi-transparent mirror. The laser detection device is also provided with a detection light source for generating a detection light beam, and the detection light beam can be reflected into a light inlet hole of the galvanometer system by the semi-reflecting and semi-transmitting mirror so as to enable the detection light beam and the laser light beam to be transmitted coaxially. The focusing lens is opposite to the light outlet of the galvanometer system and used for focusing laser beams on the bonding layer so as to heat the bonding layer; the focusing lens is also used for focusing the detection beam on the substrate and the bonding surface bonded with the bonding layer. The de-bonding surface can reflect the detection light beam to generate a reflected detection light beam, and the focusing lens is also used for enabling the reflected detection light beam to penetrate through again and to be reflected back through the vibrating mirror system and the semi-reflecting and semi-transmitting mirror. And a beam splitter prism is also arranged between the detection light source and the semi-reflecting and semi-transmitting mirror and is used for splitting the reflected detection light beam reflected by the original path. And a light spot detection component is arranged at the position opposite to the beam splitter prism so as to collect the reflected detection light beam split from the beam splitter prism. The upper computer is connected with the light spot detection assembly; the upper computer is used for controlling the galvanometer system to move the focus of the laser beam according to the reflected detection light beam so as to scan a unit area on the bonding layer; the upper computer is also used for controlling the lifting assembly to pull the sucker upwards after the unit area is scanned out, so that the substrate and the wafer are separated at the position of the unit area. The unit area is a circular ring area on the bonding layer, and the center of the circular ring area is overlapped with the center of the wafer.

In the scheme, in the laser de-bonding process, the sucker is adsorbed on the surface of the substrate, the laser beam sequentially penetrates through the sucker and the substrate and then focuses on the bonding layer, the focus of the laser beam is controlled to be in a unit area of a scanning part of the bonding layer, the sucker is pulled upwards through the lifting assembly, the substrate and the wafer are separated at the position of the unit area, the stripping mode that the sucker is pulled to separate while laser de-bonding is adopted, re-adhesion caused by re-cooling and solidification of the bonding material in a molten state between the substrate and the wafer is prevented, and therefore the stripping difficulty is reduced. And still through setting up half reflection half mirror, detection light source, beam splitter prism, facula detection subassembly and host computer to observe laser facula positional information in real time, bonding layer of local area is heated the condition information, and the host computer is convenient for control the mirror system that shakes adjusts the scanning orbit and the scanning time of laser beam, improves laser and separates bonding efficiency and effect. And laser beams can penetrate through the substrate but not through the wafer, so that the phenomenon of nonuniform laser de-bonding temperature caused by the fact that some position lasers can penetrate through and some position lasers cannot penetrate through due to a micro-circuit structure in the wafer is prevented.

In one specific embodiment, the wavelength of the detection beam is a set wavelength, the half-mirror is a lens that reflects the set wavelength and transmits other wavelengths. So as to reduce the energy loss of the laser beam generated by the laser when the laser beam penetrates the half-reflecting and half-transmitting mirror as much as possible.

In a specific embodiment, a polarizer, a beam expanding and collimating system, a shaping element and an optical isolator are further sequentially arranged on an optical path between the laser and the semi-reflecting and semi-transmitting mirror. The laser beam generated by the laser is subjected to polarization filtering, the divergence angle of the laser beam is improved, the shape of a light spot such as a circle, a square and the like is adjusted, and meanwhile, part of light transmitted by the reflected detection light beam when being reflected by the semi-reflecting and semi-transmitting mirror is isolated.

In a specific embodiment, the laser is a fiber laser, and a beam-spreading collimator is further disposed in the optical path between the fiber laser and the polarizer to further improve the divergence angle of the laser beam generated by the fiber laser prior to polarization filtering.

In a specific embodiment, a conjugate prism is further disposed on the light path between the beam splitter prism and the light spot detection assembly, so that the light spot detection assembly can collect the reflected detection light beam and obtain light spot information, explosion point growth information and the like at the focus of the laser beam.

In a specific embodiment, the detection control system further includes a four-axis displacement platform disposed below the stage, four displacement axes of the four-axis displacement platform include translation axes in an x direction, a y direction and a z direction, and a rotation axis in the z direction, wherein the z direction is perpendicular to a supporting end surface of the stage. And the upper computer is also connected with the four-axis displacement platform to control the four-axis displacement platform to move. So that the upper computer controls the four-axis displacement platform to move, and the position of the key piece to be released is convenient to finely adjust.

In a specific embodiment, the upper computer is further configured to control the galvanometer system to move a focus of the laser beam according to the reflected detection beam after the substrate and the wafer are separated at the position of the unit area, and scan another unit area on the bonding layer; the upper computer is also used for controlling the lifting assembly to pull the sucker upwards so as to separate the substrate and the wafer at the position of the other unit area. And the upper computer separates the substrate and the wafer at the position of the whole bonding layer in sequence according to the control method. The laser bonding method is convenient for laser bonding removal in a mode of laser scanning heating → separation of the pull-up sucker → laser scanning heating → separation of the pull-up sucker while scanning, and prevents bonding materials in a molten state from being cooled and solidified again to cause re-adhesion between the substrate and the wafer, thereby reducing the difficulty in peeling.

In a specific embodiment, the upper computer controls the positions of two unit areas scanned by the focal point of the laser beam successively to be adjacent. The entire bonding layer is scanned in a scan-from-inside, or outside-in, manner to completely separate the substrate from the wafer.

In a specific embodiment, the upper computer is further configured to detect the growth of the explosion point in the unit area scanned by the laser beam according to the reflected detection beam. The upper computer is also used for adjusting the step of the focal point of the moving laser beam of the galvanometer system between two adjacent explosion points in the same unit area and the step of the focal point of the moving laser beam between two adjacent unit areas in the radial direction of the wafer according to the growth condition of the explosion points. So that the control scans the step size between two adjacent explosion points in the regional in-process of every unit, be convenient for even bond layer to the unit region heats, be convenient for control the radial step-by-step between two adjacent unit regions simultaneously, prevent that radial step-by-step too big and make the bond layer not fully heated, also prevent to step-by-step undersize and lead to scanning efficiency lower. Thereby improving the efficiency and effect of laser de-bonding.

In a specific embodiment, the upper computer is further configured to calculate a mean value E of the growth cross-sectional areas of all the explosion points in the just-scanned cell region according to the reflected detection beams after the cell region is scanned. The upper computer is also used for judging whether the area of the growth section with the explosion point in the unit area is not in the range of 90-110% E; and the upper computer is also used for generating a warning signal for detecting whether the energy of the laser beam generated by the laser is normal or not when the judgment result shows that the area of the growth cross section with the explosion point in the unit area is not in the range of 90-110% E. The growth condition of the explosion point is conveniently monitored in real time, the whole unit area is conveniently scanned and heated in an even heating mode, and meanwhile, the abnormal laser beam energy generated by the laser is conveniently monitored in the first time so as to remind a user of corresponding inspection and replacement.

Drawings

Fig. 1 is a schematic structural diagram of a laser bonding-debonding detection control system according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an object stage, a suction cup and a lift assembly according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a suction cup and lift assembly according to an embodiment of the present invention;

FIG. 4 is a schematic structural view of a pull rod and a suction cup according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an adsorption end surface of a suction cup according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of an adsorption channel on an adsorption end face according to an embodiment of the present invention;

FIG. 7 is a schematic side view of a chuck according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a lifting assembly according to an embodiment of the present invention.

Reference numerals:

10-objective table 11-wafer 12-substrate 13-bonding layer 14-four-axis displacement platform

21-laser 22-focusing lens 23-vibrating mirror system 24-half-reflecting and half-transmitting mirror

25-detection light source 26-beam splitter prism 27-light spot detection assembly

30-suction cup 31-adsorption end face 32-adsorption channel 33-connection end face

34-adsorption zone 35-vacuum extractor 40-lifting component 41-pull rod

42-bracket 43-support arm 44-lifting mechanism 50-upper computer 51-displacement table controller

61-polarizer 62-beam expanding collimation system 63-shaping element

64-optical isolator 65-beam expanding collimator 66-conjugate prism

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

For convenience of understanding the laser bonding de-bonding detection control system provided in the embodiment of the present invention, an application scenario of the detection control system provided in the embodiment of the present invention is first described below, where the detection control system is applied to a laser bonding de-bonding process performed on a wafer and a substrate. The detection control system will be described in detail with reference to the accompanying drawings.

Referring to fig. 1 and 2, an inspection control system according to an embodiment of the present invention includes a stage 10, where the stage 10 is configured to hold a to-be-unbonded object thereon, where the to-be-unbonded object includes a wafer 11 fixed on a surface of the stage 10 and a substrate 12 bonded by a bonding layer 13. A suction cup 30 attached to the surface of the substrate 12 and a lift assembly 40 connected to the suction cup 30 are further provided, wherein the lift assembly 40 is used to pull the suction cup 30 upward. A laser 21 for generating a laser beam, and a galvanometer system 23 are also provided, wherein the light entrance aperture of the galvanometer system 23 is opposite to the position of the laser 21. A half-reflecting and half-transmitting mirror 24 is further arranged between the laser 21 and the light inlet of the vibrating mirror system 23, and the laser beam generated by the laser 21 can enter the light inlet of the vibrating mirror system 23 after passing through the half-reflecting and half-transmitting mirror 24. A detection light source 25 for generating a detection light beam is further provided, and the detection light beam can be reflected by the half-reflecting and half-transmitting mirror 24 into the light inlet hole of the vibrating mirror system 23, so that the detection light beam and the laser light beam are transmitted coaxially. A focusing lens 22 is further arranged, the focusing lens 22 is opposite to the light outlet of the galvanometer system 23 and is used for focusing laser beams on the bonding layer 13 so as to heat the bonding layer 13; the focusing lens 22 is also used to focus the detection beam on the de-bonding surface of the substrate 12 that is bonded to the bonding layer 13. The de-bonding surface can reflect the detection beam to generate a reflected detection beam, and the focusing lens 22 is further configured to enable the reflected detection beam to pass through again and to be reflected back through the galvanometer system 23 and the half-reflecting and half-transmitting mirror 24. A beam splitter prism 26 is further disposed between the detection light source 25 and the half-reflecting and half-transmitting mirror 24, and the beam splitter prism 26 is used for splitting the reflected detection light beam reflected back from the original path. A spot detection assembly 27 is also provided opposite the beam splitter prism 26 to collect the reflected detection beam split off from the beam splitter prism 26. An upper computer 50 connected with the light spot detection assembly 27 is also arranged; the upper computer 50 is used for controlling the galvanometer system 23 to move the focus of the laser beam according to the reflected detection beam so as to scan a unit area on the bonding layer 13; the upper computer 50 is also used to control the lift assembly 40 to pull the chuck 30 upward after the unit area is scanned out, to separate the substrate 12 and the wafer 11 at the unit area location. The unit region is a circular ring region on the bonding layer 13, and the center of the circular ring region coincides with the center of the wafer 11.

In the above scheme, in the laser de-bonding process, the suction cup 30 is adsorbed on the surface of the substrate 12, the laser beam sequentially penetrates through the suction cup 30 and the substrate 12 and then focuses on the bonding layer 13, and after the focal point of the laser beam is controlled in a unit area of a scanning portion of the bonding layer 13, the suction cup 30 is pulled upwards by the lifting assembly 40, so that the substrate 12 and the wafer 11 are separated at the position of the unit area, and the substrate 12 and the wafer 11 are prevented from being bonded again due to the fact that the bonding material in a molten state is cooled and solidified again by adopting a peeling mode that the suction cup 30 is pulled to separate while laser de-bonding is performed, so that the peeling difficulty is reduced. And the semi-reflecting and semi-transparent mirror 24, the detection light source 25, the beam splitter prism 26, the light spot detection assembly 27 and the upper computer 50 are arranged, so that the laser light spot position information and the heating condition information of the bonding layer 13 in a local area can be observed in real time, the upper computer 50 can control the vibrating mirror system 23 to adjust the scanning track and the scanning time of the laser beam, and the laser bonding resolution efficiency and effect are improved. The laser beam is enabled to transmit through the substrate 12 but not through the wafer 11, so that the phenomenon of nonuniform laser de-bonding temperature caused by the fact that some position laser can be transmitted and some position laser cannot be transmitted due to the micro-circuit structure in the wafer 11 is prevented. The above-described respective structural devices will be described in detail with reference to the drawings.

In setting up the stage 10, and with reference to fig. 1 and 2, the stage 10 acts as a support structure for holding a member to be debonded thereon. When provided, a stage body having a supporting end surface may be provided as the stage 10. The support end face may be provided in a circular shape so as to place a disk-shaped member to be debonded thereon. And a plurality of suction holes may be further provided on the supporting end surface of the stage 10, and the plurality of suction holes are adsorbed on the surface of the wafer 11 in the to-be-debonded member to fix the wafer 11 on the stage 10. Of course, other securing means capable of holding the wafer 11 thereon may be employed. By allowing the laser beam to pass through the substrate 12 but not through the wafer 11, the laser de-bonding temperature non-uniformity caused by the position laser being able to pass through and the position laser being unable to pass through due to the micro-circuit structure inside the wafer 11 is prevented.

When the suction cup 30 is provided, referring to fig. 3, 4, 5, 6 and 7, the suction cup 30 may have a disk shape so as to suck the disk-shaped member to be unbonded. The suction cup 30 has a suction end surface 31 and a connection end surface 33 opposite to each other, and as shown in fig. 3, the upper surface of the suction cup 30 is the connection end surface 33, and the lower surface of the suction cup 30 is the suction end surface 31. The absorption end face 31 is used for absorbing the surface of the substrate 12, and the connection end face 33 is used for connecting the lifting assembly 40 so as to lift a partial area of the suction cup 30 upwards, so that the wafer 11 and the substrate 12 are separated in the partial area or the whole area. As shown in fig. 3, 4, 5 and 6, the suction end surface 31 of the suction cup 30 may be divided into at least three suction areas 34, and the at least three suction areas 34 include a circular suction area 34 located at the center of the suction cup 30 and at least two circular suction areas 34 sequentially arranged outward from the circular suction area 34. That is, at least three suction areas 34 are provided on the end surface of the suction cup 30, the three suction areas 34 include a circular suction area 34 located at the center of the suction cup 30, and at least two circular suction areas 34 are further provided, and the at least two circular suction areas 34 are sequentially arranged from inside to outside from the circular suction area 34 located at the center, so that when the end surface of the suction cup 30 is sucked on the surface of the substrate 12, the at least three suction areas 34 on the suction end surface 31 are sucked on the surface of the substrate 12. When the number of the adsorption regions 34 is determined, the number of the adsorption regions 34 shown in fig. 3 is 4, and the adsorption regions include a circular adsorption region 34 located at the center and 3 circular adsorption regions 34 arranged in sequence from inside to outside. It should be understood that the number of the divided adsorption regions 34 on the adsorption end face 31 is not limited to the arrangement of 4 as shown in fig. 3, and besides, the number of the adsorption regions 34 on the adsorption end face 31 may be any value not less than 3, such as 3, 5, 6, 8, 12, 18, etc. In addition, the above description shows only one arrangement of suction cup 30, and other arrangements may be used.

In addition, the upper computer 50 can control the galvanometer system 23 to move the focus of the laser beam according to the reflected detection beam, and a unit area scanned on the bonding layer 13 is opposite to one adsorption area 34 on the chuck 30, that is, each unit area corresponds to one adsorption area 34 on the chuck 30. The unit area at the central position corresponds to the circular suction area 34 at the central position on the suction cup 30, and the unit area at the non-central position corresponds to the circular suction area 34 at the opposite position on the suction cup 30. Since each unit area is a circular ring area on the bonding layer 13, and the center of the circular ring area coincides with the center of the wafer 11, the bonding layer 13 corresponding to the circular adsorption area 34 located at the center position on the suction cup 30 still adopts a circular ring scanning track mode to perform thermal debonding on the bonding layer 13 located at the position of the circular adsorption area 34, so that the bonding layer 13 of the unit area at the center position can be sufficiently thermally debonded, and the debonding effect is improved. After scanning out the cell area, the upper machine 50 is also used to control the lift assembly 40 to pull the chuck 30 upward to separate the substrate 12 and the wafer 11 at the cell area location.

Referring to fig. 2 and 3, a lift assembly 40 is further provided to lift the chucks 30 of the different suction areas 34 to separate the wafer 11 from the substrate 12 at the different chuck 30 areas. Specifically, the number of the groups of the lifting assemblies 40 is at least three, the at least three groups of lifting assemblies 40 correspond to the at least three adsorption regions 34 one by one, and each group of lifting assemblies 40 is used for pulling up the corresponding adsorption region 34 after the bonding layer 13 at the position corresponding to the adsorption region 34 is heated by laser to undergo phase change, so that the wafer 11 and the substrate 12 are separated at the position corresponding to the adsorption region 34, and the substrate 12 and the wafer 11 at the just-scanned unit region are separated. As shown in fig. 2 and 3, the number of the sets of the lifting assemblies 40 is 4, the 4 sets of the lifting assemblies 40 respectively correspond to 4 adsorption areas 34 on the adsorption end surface 31, each adsorption area 34 corresponds to one set of the lifting assemblies 40, and each set of the lifting assemblies 40 is used for lifting the suction cup 30 at the position corresponding to the adsorption area 34, so that the wafer 11 and the substrate 12 are separated at the position corresponding to the adsorption area 34. Here, the position of each adsorption region 34 of the wafer 11 and the substrate 12 refers to a portion of the substrate 12 adsorbed by each adsorption region 34 and a portion of the wafer 11 which is vertically opposite to the portion of the substrate 12. By dividing the suction end surface 31 of the suction cup 30 into at least three suction areas 34, a group of lifting assemblies 40 is correspondingly arranged on each suction area 34, so that a pulling force can be individually applied to a certain suction area 34 of the suction cup 30. In the laser de-bonding process, the corresponding adsorption area 34 of the sucker 30 can be lifted immediately after the bonding layer 13 area of the laser scanning part is scanned, so that the two layer structures at the position of the adsorption area 34 are separated, the sucker 30 does not need to be applied with pulling force after the whole bonding layer 13 is scanned with laser, the time from the scanning of the bonding layer 13 of the part area to the separation of the wafer 11 and the substrate 12 of the part area is shortened, the bonding layer 13 in a molten state is prevented from being heated by the laser to be condensed and bonded again, the sucker 30 does not need to be applied with large pulling force, and the stripping difficulty is reduced; and the bonding layer 13 does not need to be scanned for multiple times, so that the stripping time is shortened, and the stripping efficiency is improved.

Referring to fig. 7, at least three vacuum pumps 35 may be provided, the at least three vacuum pumps 35 corresponding to the at least three adsorption zones 34 one by one, each vacuum pump 35 being used to adjust the suction force of the corresponding adsorption zone 34. As shown in fig. 7, 4 vacuum pumps 35 are provided, and each vacuum pump 35 corresponds to one adsorption region 34. That is, each suction area 34 is provided with a vacuum extractor 35 to individually adjust the suction force of the corresponding suction area 34, so that the suction forces generated by different suction areas 34 are different, and when one lifting assembly 40 lifts the suction cup 30 at the position corresponding to the suction area 34, the suction force of the suction area 34 is increased or decreased according to the difficulty of lifting the suction cup 30 at the position corresponding to the suction area 34. For example, the suction force of at least three suction areas 34 may be increased from the outer circumference to the inner circumference of the suction end surface 31, so that the suction force generated by the suction area 34 near the center is larger and the suction force generated by the suction area 34 near the edge is smaller. When the lifting assembly 40 lifts the suction cups 30 close to the edge suction areas 34, the area of the edge suction areas 34 is larger, and the lever of the suction force is larger, so that the lifting difficulty is smaller. The area of the suction area 34 near the center is smaller, and the lever for suction is smaller, so that the lifting difficulty is higher. By adopting the arrangement mode that the suction force of the suction area 34 near the central position is larger, and the suction force of the suction area 34 near the edge position is smaller, the suction force between the suction area 34 and the substrate 12 is too small to cause the separation of the suction cup 30 and the substrate 12 when the suction area 34 positioned at the inner ring is lifted by the corresponding lifting assembly 40.

In addition, when each adsorption region 34 is provided, referring to fig. 6, a plurality of circles of adsorption channels 32 may be provided on the adsorption end surface 31 in a concentric circle shape. That is, each circle of the adsorption channel 32 is a circular ring, and a convex end surface is arranged between two adjacent circles of the adsorption channels 32 so as to be attached to the surface of the substrate 12. The number of passes 32 in each adsorption zone 34 may be 1, 2, 3, 5, 10, etc. The suction of the suction cup 30 to the partial annular area of the substrate 12 is realized by the negative pressure generated in each circle of the suction channel 32, and then the lifting assembly 40 drives the suction cup 30 to move upwards a little, so that the partial annular areas which are just bonded in the two layer structures generate gaps and are separated, and the suction force with the same size is applied to the surface of the substrate 12 in the same annular area.

In providing each of the lift assemblies 40, referring to fig. 4, the lift assembly 40 corresponding to the circular suction region 34 located at the central position and the lift assembly 40 corresponding to the circular suction region 34 located at the non-central position may be provided in different structures. Specifically, each of the at least two sets of lift assemblies 40 corresponding to the at least two annular suction areas 34 may include at least three tie rods 41 and a lift mechanism 44. Namely, the lifting assembly 40 corresponding to each circular ring-shaped adsorption area 34 comprises at least three pull rods 41, and each pull rod 41 in the three pull rods 41 is connected with the connecting end surface 33 of the suction cup 30. As shown in fig. 4, each lifting assembly 40 corresponding to each circular ring-shaped adsorption area 34 includes 3 tie bars 41, and it should be noted that the arrangement of the 3 tie bars 41 shown in fig. 4 is not limited in the lifting assembly 40 corresponding to each circular ring-shaped adsorption area 34, and besides, 4 tie bars 41, 5 tie bars 41, 6 tie bars 41, etc. may also be used. The number of the pull rods 41 in the lifting assemblies 40 corresponding to different circular ring-shaped adsorption areas 34 may be set in the same manner as shown in fig. 4, or the number of the pull rods 41 in the lifting assemblies 40 corresponding to different circular ring-shaped adsorption areas 34 may be different. In particular, the number of tension rods 41 in the edge lift assemblies 40 may be greater, and the number of tension rods 41 in the center lift assemblies 40 may be less. Or a smaller number of tension rods 41 in the edge lift assemblies 40 and a larger number of tension rods 41 in the center lift assemblies 40. Referring to fig. 4, the connection points of all the pull rods 41 and the connection end surfaces 33 in the same group of lifting assemblies 40 are circumferentially and uniformly distributed around the center of the suction cup 30, that is, the connection points of all the pull rods 41 and the suction end surfaces 31 in the lifting assemblies 40 corresponding to each circular ring-shaped suction area 34 are circumferentially and uniformly distributed around the center of the suction cup 30, so as to uniformly pull the suction cup 30 at each circular ring-shaped suction area 34. The lifting mechanism 44 is used for lifting at least three pull rods 41 along the axial direction of the suction cup 30, that is, the pulling force exerted on each pull rod 41 is parallel to the axial direction of the suction cup 30, so that the pulling direction of the pull rod 41 is parallel to the separation direction of the two layer structures at the separation of the suction areas 34, and the difficulty of separating the two layer structures at the position of each suction area 34 is simplified. So as to uniformly apply a pulling force to each circular ring-shaped adsorption area 34 and prevent the substrate 12 from being deformed inconsistently in the circumferential direction of each circular ring-shaped adsorption area 34.

With continued reference to fig. 4, the connection points between the at least three pull rods 41 and the connection end surface 33 in each set of lifting assemblies 40 may be located in the circular adsorption region 34 corresponding to the set of lifting assemblies 40, that is, the connection points between all the pull rods 41 and the connection end surface 33 in the lifting assembly 40 corresponding to each adsorption region 34 are located at the position corresponding to the adsorption region 34, so that the connection points between all the pull rods 41 and the connection end surface 33 in one set of lifting assemblies 40 are closer to the circular adsorption region 34 corresponding to the set of lifting assemblies 40, thereby improving the lifting efficiency and effect. Of course, it is within the scope of this patent to not limit the arrangement described above so long as it facilitates separation of the two layer structures in each adsorption zone 34.

As shown in fig. 4, when the lifting assembly 40 corresponding to the centrally located circular suction area 34 is provided, the set of lifting assemblies 40 corresponding to the circular suction area 34 includes a center rod 41 and a lifting mechanism 44. The connection point between the center rod 41 and the suction cup 30 is located at the center of the connection end surface 33, and the lifting mechanism 44 is used for lifting the center rod 41 in the axial direction of the suction cup 30. Namely, a central pull rod 41 is arranged at the center of the circular adsorption area 34 as a tensile connecting piece, and the central pull rod 41 is arranged at the center, so that the sucker 30 is pulled from the center of the circular adsorption area 34, thereby overcoming the defect that the substrate 12 is deformed inconsistently in the circumferential direction of the circular adsorption area 34. It should be noted that the arrangement of the lifting assembly 40 corresponding to the circular suction area 34 is not limited to the arrangement of one central rod 41 shown above, and other arrangements may be adopted. For example, the lifting assembly 40 corresponding to the circular absorption region 34 at the center may be arranged in the same manner as the lifting assembly 40 corresponding to the circular absorption region 34. I.e. the lifting assembly 40 corresponding to the circular suction zone 34, also has at least three tie rods 41, which at least three tie rods 41 are distributed circumferentially and evenly around the centre of the suction cup 30.

In addition, referring to fig. 4, the connection point between the pull rod 41 and the connection end surface 33 in any two adjacent groups of the at least three groups of lifting assemblies 40 can be gradually reduced from the edge of the suction cup 30 to the center of the suction cup 30 in the radial direction of the suction cup 30. It should be noted that the step of the connection point between the pull rod 41 and the connecting end surface 33 in the radial direction of the suction cup 30 in the two adjacent groups of lifting assemblies 40 refers to the distance between the connection point between the pull rod 41 and the connecting end surface 33 in the radial direction of the suction cup 30 in the two adjacent groups of lifting assemblies 40. The larger the distance is, the larger the step is, the larger the distance between the connecting points between the pull rods 41 and the connecting end surfaces 33 in the two adjacent groups of lifting assemblies 40 in the radial direction of the suction cups 30 is; conversely, the smaller the distance, the smaller the step, which means the smaller the distance between the connecting point between the pull rod 41 and the connecting end surface 33 of the two adjacent groups of lifting assemblies 40 in the radial direction of the suction cup 30. The radial stepping of the connection point between the pull rod 41 and the connection end surface 33 in any two adjacent groups of lifting assemblies 40 in the suction cup 30 gradually decreases from the edge of the suction cup 30 to the center of the suction cup 30, which means that the radial stepping of the connection point between the pull rod 41 and the connection end surface 33 in two adjacent groups of lifting assemblies 40 close to the edge is larger, and the radial stepping of the connection point between the pull rod 41 and the connection end surface 33 in two adjacent groups of lifting assemblies 40 close to the center is smaller in the suction cup 30, so as to counteract the influence of the difficulty of deformation of the inner ring of the substrate 12 relative to the outer ring, and make the lifting height of each group of lifting assemblies 40 to the corresponding adsorption area 34 more consistent.

Referring to fig. 8, each of the at least two sets of lift assemblies 40 of the at least two annular adsorbent zones 34 may further comprise a support 42, wherein the support 42 comprises at least three arms 43, and the at least three arms 43 correspond to the at least three pull rods 41 of the corresponding set of lift assemblies 40 one by one. Wherein each support arm 43 is connected with a corresponding pull rod 41, and the axial direction of each pull rod 41 is parallel to the axial direction of the suction cup 30. Namely, a bracket 42 is further arranged in the lifting assembly 40 corresponding to each circular ring-shaped adsorption area 34, so that all the pull rods 41 in the lifting assembly 40 are connected into a whole structure. Specifically, the lifting mechanism 44 raises all of the tension rods 41 in the lifting assembly 40 by lifting the support bracket 42 by connecting all of the tension rods 41 in the lifting assembly 40 to the support arm 43 of the support bracket 42 to apply a relatively uniform tension to all of the tension rods 41 in the same set of lifting assemblies 40.

Of course, when there is only one central rod 41 in the lifting assembly 40 corresponding to the circular absorption area 34 located at the central position, the bracket 42 may not be provided, and the lifting mechanism 44 may lift the central rod 41 directly. The same setting mode as that of the lifting assembly 40 of the circular adsorption area 34 is adopted in the lifting assembly 40 corresponding to the circular adsorption area 34, and when at least three pull rods 41 are also included, the plurality of pull rods 41 can be connected into a whole in the mode of the support 42, so that the lifting mechanism 44 can lift the plurality of pull rods 41 together, and more consistent pulling force is applied to all the pull rods 41 in the same group of lifting assemblies 40.

When the lifting mechanism 44 is provided, with continued reference to fig. 8, the lifting mechanism 44 may be a rack and pinion lifter, the rack of the rack and pinion lifter is fixedly connected to the arm 43 or the central pull rod 41, and the transmission direction of the rack coincides with the axial direction of the suction cup 30. To simplify the construction of the lifting mechanism 44. It should be understood that the lifting mechanism 44 is not limited to a rack and pinion lifter arrangement, and other arrangements may be used. For example, a lead screw lifter can be used as the lifting mechanism 44, and a lead screw of the lead screw lifter is connected with the bracket 42 or the central pull rod 41, so that the pull rod 41 and the suction cup 30 can be lifted.

Of course, the materials of the suction cup 30, the substrate 12, the pull rod 41 and the center pull rod 41 may be the same, so as to select the laser wavelength, so that the laser can perform laser debonding on the bonding layer 13 through the suction cup 30 and the substrate 12, and meanwhile, the pull rod 41 or the center pull rod 41 does not affect the penetration efficiency of the laser, and the influence of the pull rod 41 on the uneven scanning of the bonding layer 13 is prevented. Specifically, the materials of the chuck 30, the substrate 12, the pull rod 41 and the center pull rod 41 may all be quartz materials to prevent the chuck 30 and the substrate 12 from affecting the laser transmissivity.

In addition, the detection control system for laser de-bonding includes not only the above-mentioned objective table 10, the suction cup 30 and the lifting assembly 40, referring to fig. 1, but also a laser system for generating a laser beam, referring to fig. 1, the laser beam sequentially penetrates through the suction cup 30 and the substrate 12 from top to bottom, and then focuses on the bonding layer 13 of the to-be-bonded piece to heat the bonding layer 13, so as to convert the bonding layer 13 material from a bonded solid state to a non-bonded or molten state with a small bonding force, a gas or a plasma state, and the like, thereby achieving de-bonding between the wafer 11 and the substrate 12. In setting up the laser system, and with reference to fig. 1, the laser system comprises a laser 21, which laser 21 is arranged to generate a laser beam. A galvanometer system 23 is further arranged, and a light inlet of the galvanometer system 23 is opposite to the laser 21, so that the laser beam generated by the laser 21 can enter the galvanometer system 23. A focusing lens 22 is further disposed at a position opposite to the light exit hole of the galvanometer system 23, and the focusing lens 22 is opposite to the light exit hole of the galvanometer system 23 and is used for focusing a laser beam on the bonding layer 13 to heat the bonding layer 13. When the focusing lens 22 is provided, a telecentric lens may be employed as the focusing lens 22 to improve the focusing effect. Of course, a plano-convex lens or a cylindrical lens may also be employed as the focusing lens 22. The galvanometer system 23 can control the focus of the laser beam to scan on the bonding layer 13 so as to scan a plurality of unit areas on the bonding layer 13, thereby splicing the heating debonding bonding of the whole bonding layer 13 by the plurality of unit areas. A galvanometer system 23 is provided to control the focus of the laser beam to scan across the bonding layer 13. Specifically, the galvanometer system 23 may be a biaxial galvanometer system 23 or a triaxial galvanometer system 23.

With continued reference to fig. 1, a detection optical path system is also included in the detection control system. When the laser system is installed, as shown in fig. 1, a half-reflecting and half-transmitting mirror 24 is further disposed between the laser 21 and the light inlet of the galvanometer system 23, and a laser beam generated by the laser 21 can penetrate through the half-reflecting and half-transmitting mirror 24 and then enter the light inlet of the galvanometer system 23, so that the half-reflecting and half-transmitting mirror 24 does not affect the optical path transmission of the laser beam. A detection light source 25 for generating a detection light beam is further arranged at the position opposite to the half-reflecting and half-transmitting mirror 24, and the detection light beam can be reflected to the light inlet of the vibrating mirror system 23 by the half-reflecting and half-transmitting mirror 24 so as to be transmitted coaxially with the laser light beam. The focusing lens 22 is also used to focus the detection beam on the de-bonding surface of the substrate 12 that is bonded to the bonding layer 13. When the detection light beam is transmitted to the bonding surface between the substrate 12 and the bonding layer 13, the detection light beam can return in the original path, so that information such as a light spot image, an explosion point image, a position image and the like at the focusing position of the laser beam is transmitted out, and the state of laser bonding is monitored in real time. When the original path returns, the bonding splitting surface can reflect the detection light beam to generate a reflected detection light beam, and the reflected detection light beam comprises light spot information, explosion point information and the like. The focusing lens 22 is also used for making the reflected detection beam to transmit again and reflect back through the vibrating mirror system 23 and the half-reflecting and half-transmitting mirror 24. As shown in fig. 1, a beam splitter prism 26 is further disposed between the detection light source 25 and the half-reflecting and half-transmitting mirror 24, and the beam splitter prism 26 is used for splitting the reflected detection light beam reflected back from the primary path. A spot detection assembly 27 is further disposed at a position opposite to the beam splitter prism 26 to collect the reflected detection beam split from the beam splitter prism 26, so as to image the reflected detection beam, and observe spot position information, heating condition, explosion point distribution condition, stepping condition, etc. focused on the bonding layer 13. In setting the light spot detection assembly 27, a CCD camera may be employed as the light spot detection assembly 27. Through setting up half reflection half mirror 24, detection light source 25, beam splitter prism 26, facula detection subassembly 27 and host computer 50 to observe laser facula positional information in real time, bonding layer 13 in local area is heated the condition information, and the host computer 50 control of being convenient for shakes mirror system 23 and adjusts the scanning orbit and the scanning time of laser beam, improves laser and separates bonding efficiency and effect.

Referring to fig. 1, when the half mirror 24 is provided, the half mirror 24 may block and reflect only the detection beam, and allow other beams to pass therethrough. Specifically, when the wavelength of the detection beam is the set wavelength, the half-reflecting and half-transmitting mirror 24 may be a lens in which the set wavelength is reflected and other wavelengths are transmitted. To minimize the energy loss of the laser beam generated by the laser 21 when passing through the half mirror 24.

As shown in fig. 1, a polarizer 61, a beam expanding and collimating system 62, a shaping element 63 and an optical isolator 64 may be sequentially disposed on the optical path between the laser 21 and the half-reflecting and half-transmitting mirror 24. The polarizer 61 is used for polarization filtering of the laser beam generated by the laser 21 so as to obtain polarized light in the same polarization direction, which is convenient for the subsequent galvanometer system 23 to move the laser beam scanning and focusing by the focusing lens 22. The expanded beam collimation system 62 is used to improve the divergence angle of the laser beam to obtain a laser beam with a suitable cross-sectional area. The shaping element 63 is used to adjust the spot shape, such as a circle, a square, etc., to control the cross-sectional shape of the focal point of the laser beam focused on the bonding layer 13. The optical isolator 64 is used to isolate the portion of the reflected detection beam that is transmitted when reflected by the transflective mirror 24 to reduce interference with the laser beam. In addition, as shown in fig. 1, when the laser 21 is the fiber laser 21, a beam expanding collimator 65 may be further provided on the optical path between the fiber laser 21 and the polarizer 61 to improve the divergence angle of the laser beam generated by the fiber laser 21 before polarization filtering.

With continued reference to fig. 1, a conjugate prism 66 may be further disposed on the light path between the beam splitter prism 26 and the light spot detection assembly 27, so that the light spot detection assembly 27 can collect the reflected detection light beam and obtain the light spot information, the explosion point growth information, and the like at the focal point of the laser beam.

As shown in fig. 1, an upper computer 50 connected to the light spot detection assembly 27 is further provided, and the upper computer 50 has functions of collecting information and generating control commands to control the movement of the suction cup 30, the lifting assembly 40, the galvanometer system 23, and the like. Specifically, a notebook computer, a desktop computer, an industrial personal computer, or the like can be used as the upper computer 50. The upper computer 50 is connected to the light spot detection assembly 27 to receive information such as a light spot image and an explosion spot image displayed by the reflected detection light beam collected by the light spot detection assembly 27. In operation, the upper computer 50 is configured to control the galvanometer system 23 to move the focal point of the laser beam according to the reflected detection beam, so as to scan a unit area on the bonding layer 13, that is, control the focal point of the laser beam to scan a unit area of an annular area on the bonding layer 13 around the center of the wafer 11, so as to perform thermal pyrolysis bonding on the bonding layer 13 in the unit area, so that the bonding layer 13 in the unit area is in a molten state, a gasified state, and the like. The upper computer 50 is also used to control the lift assembly 40 to pull the chuck 30 upward after the unit area is scanned out, to separate the substrate 12 and the wafer 11 at the unit area location. Therefore, after the focal point of the laser beam is controlled to be in a unit area of a scanning part of the bonding layer 13, the suction cup 30 is pulled upwards by the lifting assembly 40, so that the substrate 12 and the wafer 11 are separated at the position of the unit area, and the separation mode of separating the substrate 12 from the wafer 11 by pulling the suction cup 30 while laser debonding is adopted, so that the substrate 12 and the wafer 11 are prevented from being bonded again due to the fact that the bonding material in a molten state is cooled and solidified again, and the separation difficulty is reduced.

As shown in fig. 1 and 2, a four-axis displacement platform 14 may be disposed below the object stage 10, and the object stage 10 is disposed on the four-axis displacement platform 14 to move the object stage 10. The four displacement axes in the four-axis displacement platform 14 include translation axes in the x direction, the y direction and the z direction, and further include a rotation axis in the z direction, wherein the z direction is perpendicular to the supporting end face of the stage 10, so as to realize translation in 3 directions such as up-down direction, left-right direction, front-back direction, and the like, and simultaneously realize rotation in the z direction, so that the bonding piece to be released can rotate in the horizontal plane. Referring to fig. 1, the upper computer 50 is further connected to the four-axis displacement platform 14 to control the four-axis displacement platform 14 to move. So that the upper computer 50 controls the four-axis displacement platform 14 to move, and the position of the key piece to be released is finely adjusted. Of course, referring to fig. 1, a displacement stage controller 51 may also be provided as a controller for individually controlling the four-axis displacement platform 14, the displacement stage controller 51 is connected to the upper computer 50, so that a control command generated or received by the upper computer 50 is transmitted to the displacement stage controller 51, and the displacement stage controller 51 controls the movement of the four-axis displacement platform 14.

With continued reference to fig. 1 and 2, during the laser debonding process, the suction cup 30 may be sucked onto the surface of the substrate 12, so that after the laser debonding process is performed on a certain unit region of the bonding layer 13, that is, by pulling up the suction cup 30, a gap is generated between the wafer 11 and the substrate 12 at a position coinciding with the unit region, so as to locally separate the two. Specifically, the laser beam generated by the laser system needs to sequentially pass through the chuck 30 and the substrate 12 before being focused on the bonding layer 13, i.e., the laser beam needs to pass through not only the substrate 12 but also the chuck 30. The chuck 30 is also always attracted to the surface of the substrate 12 while controlling the focal point of the laser beam to scan on the bonding layer 13.

After scanning one unit area and lifting the chuck 30 at the unit area to separate the wafer 11 and the substrate 12 at the unit area, the upper computer 50 is further configured to control the galvanometer system 23 to move the focal point of the laser beam according to the reflected detection beam, so as to scan another unit area on the bonding layer 13, i.e. continue to scan to form the next unit area. After scanning the next unit area, the upper computer 50 is also used to control the lift assembly 40 to pull the chuck 30 upward to separate the substrate 12 and the wafer 11 at another unit area location. The upper computer 50 separates the substrate 12 and the wafer 11 at the position of the whole bonding layer 13 in sequence according to the control method. The laser bonding is performed in a manner of laser scanning heating → separation of the pull-up chuck 30 → laser scanning heating → separation of the pull-up chuck 30 while scanning, and the bonding material in a molten state is prevented from being cooled and solidified again to cause re-adhesion between the substrate 12 and the wafer 11, thereby reducing the difficulty in peeling.

For example, referring to fig. 3, 4 and 5, when the laser beam scans the bonding layer 13 region at one of the absorption regions 34, the suction cup 30 at the absorption region 34 may be lifted by the lifting assembly 40 corresponding to the absorption region 34, so that the wafer 11 and the substrate 12 generate a gap at the absorption region 34, thereby achieving local separation. When the bonding layer 13 (another unit region) at the position of the other adsorption region 34 is scanned by a subsequent laser beam, the bonding layer 13 region which is heated at the position of the adsorption region 34 and is unbonded is prevented from being condensed again and bonded, and the two layer structures at the adsorption region 34 can be separated in the first time after the laser beam scans the adsorption region 34. In turn, after the laser beam scans the bonding layer 13 area at the next suction area 34, the lifting assembly 40 corresponding to the next suction area 34 lifts the suction cup 30 at the suction area 34, so as to separate the two layer structures at the position of the suction area 34. In turn, the laser beam scanning de-bonding → the corresponding lifting assembly 40 lifts the suction cup 30 at the suction area 34 for separating the two layer structures at the suction area 34. Therefore, the whole bonding layer 13 is subjected to bonding removal, and the whole bonding layer 13 area of the two layer structures is lifted and separated, so that the two layer structures are thoroughly subjected to bonding removal.

In addition, two unit areas scanned successively by the focal point of the laser beam controlled by the upper computer 50 may be adjacent to each other, so as to scan the whole bonding layer 13 in an inside-out or outside-in scanning manner, so as to completely separate the substrate 12 and the wafer 11. For example, when the upper computer 50 controls the focal point of the laser beam to scan the bonding layer 13, the scanning may be started from the region of the bonding layer 13 at the position of the outer-most absorption region 34, and the corresponding lifting assembly 40 is started to lift and separate. And scanning all the bonding layers 13 at the positions of the adsorption areas 34 from the outer circle to the inner circle in sequence, thereby realizing the scanning of the whole bonding layer 13 area. When the inner ring is subjected to debonding, the outer ring is already subjected to debonding to form a molten state, a gaseous state or a plasma state substance, so that the bonding materials in the molten state, the gaseous state or the plasma state and the like generated in the debonding process of the inner ring can overflow outwards.

When the upper computer 50 specifically performs detection, the upper computer 50 may detect the growth condition of the explosion point in the unit area scanned by the laser beam according to the reflected detection beam. Then, the upper computer 50 can adjust the step of the focal point of the laser beam moved by the galvanometer system 23 between two adjacent shot points in the same unit area and the step of the focal point of the laser beam in the radial direction of the wafer 11 between two adjacent unit areas according to the growth condition of the shot points. The step between two adjacent explosion points in the same unit area refers to the distance between the centers of the two adjacent explosion points emitted by the laser beams along the circumferential direction of the unit area. The smaller the step between two adjacent explosion points, the denser the explosion points emitted by the laser beam are. Conversely, the larger the step between two adjacent explosion points is, the more sparse the explosion points emitted by the laser beam are. By the detection system shown above, the step size between two adjacent explosion points in the process of scanning each unit area is controlled, so that the bonding layer 13 of the unit area is heated uniformly. The step of the two adjacent unit areas in the radial direction of the wafer 11 refers to the interval between the center lines of the two adjacent unit areas in the radial direction of the wafer 11. If the step of the two adjacent unit areas in the radial direction of the wafer 11 is smaller, the density between the two adjacent unit areas is denser. If the step of the two adjacent unit areas in the radial direction of the wafer 11 is larger, the sparseness between the two adjacent unit areas is illustrated. Through the detection system and the upper computer 50, the radial stepping between two adjacent unit areas is convenient to control, the bonding layer 13 is prevented from being not sufficiently heated due to overlarge radial stepping, and the scanning efficiency is also prevented from being lower due to undersize stepping. Thereby improving the efficiency and effect of laser de-bonding.

In addition, after the cell region is scanned, the upper computer 50 may further calculate a mean value E of the growth cross-sectional areas of all the explosion points in the just scanned cell region according to the reflected detection light beams, so as to calculate an approximate value of the growth cross-sectional areas of all the explosion points in the cell region. And after the calculation is completed, the upper computer 50 may further determine whether the growth cross-sectional area of the explosion point in the cell region is not within the range of 90% E to 110% E. If the growth cross-sectional areas of all the explosion points in the unit area are within the range of 90% E to 110% E, that is, the growth cross-sectional area without the explosion points is not outside the range of 90% E to 110% E, it is described that when the focal point of the laser beam scans the unit area, the scanning is performed with more consistent laser energy, the heating condition of the bonding layer 13 in the unit area is also more consistent, and the debonding effect is better. Of course, if the growth cross-sectional area of the explosion point is not in the range of 90% E to 110% E, it means that when the focal point of the laser beam scans the cell region, the fluctuation of the laser energy is large, the heating conditions of the bonding layer 13 in the cell region are not consistent, and the bonding solution effect is not good. Therefore, the upper computer 50 can generate a warning signal for detecting whether the energy of the laser beam generated by the laser 21 is normal or not when the judgment result shows that the area of the growth cross section where the explosion point exists in the unit region is not in the range of 90% E to 110% E. The growth condition of the explosion point is conveniently monitored in real time, the whole unit area is conveniently scanned and heated in an even heating mode, and meanwhile, the abnormal laser beam energy generated by the laser 21 is conveniently monitored in the first time, so that a user is reminded to carry out corresponding inspection and replacement.

In the laser de-bonding process, the suction cup 30 is adsorbed on the surface of the substrate 12, the laser beam sequentially penetrates through the suction cup 30 and the substrate 12 and then focuses on the bonding layer 13, the focus of the laser beam is controlled to be in a unit area of a scanning part of the bonding layer 13, the suction cup 30 is pulled upwards through the lifting assembly 40, the substrate 12 and the wafer 11 are separated at the position of the unit area, and the separation mode that the suction cup 30 is pulled to separate while laser de-bonding is adopted, so that the bonding material in a molten state is prevented from being cooled and solidified again to be adhered again between the substrate 12 and the wafer 11, and the separation difficulty is reduced. And the semi-reflecting and semi-transparent mirror 24, the detection light source 25, the beam splitter prism 26, the light spot detection assembly 27 and the upper computer 50 are arranged, so that the laser light spot position information and the heating condition information of the bonding layer 13 in a local area can be observed in real time, the upper computer 50 can control the vibrating mirror system 23 to adjust the scanning track and the scanning time of the laser beam, and the laser bonding resolution efficiency and effect are improved. The laser beam is enabled to transmit through the substrate 12 but not through the wafer 11, so that the phenomenon of nonuniform laser de-bonding temperature caused by the fact that some position laser can be transmitted and some position laser cannot be transmitted due to the micro-circuit structure in the wafer 11 is prevented.

The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A laser debonding detection control system, comprising:

an object stage for holding a member to be unbonded thereon; the bonding piece to be debonded comprises a wafer fixed on the surface of the objective table and a substrate bonded through a bonding layer;

a suction cup adsorbed on the surface of the substrate;

a lifting assembly connected to the suction cup for pulling the suction cup upward;

a laser for generating a laser beam;

the light inlet hole of the galvanometer system is opposite to the position of the laser;

the half-reflecting and half-transmitting mirror is positioned between the laser and the light inlet of the vibrating mirror system; and the laser beam generated by the laser can enter the light inlet of the galvanometer system after penetrating through the semi-reflecting and semi-transparent mirror;

the detection light source is used for generating a detection light beam, and the detection light beam can be reflected into a light inlet hole of the galvanometer system by the semi-reflecting and semi-transmitting mirror so that the detection light beam and the laser beam are transmitted coaxially;

the focusing lens is opposite to the light outlet hole of the galvanometer system and used for focusing the laser beam on the bonding layer so as to heat the bonding layer; the focusing lens is also used for focusing the detection light beam on a bonding-removing surface bonded with the bonding layer on the substrate; the de-bonding surface can reflect the detection light beam to generate a reflected detection light beam, and the focusing lens is also used for enabling the reflected detection light beam to penetrate through again and to be reflected back through the galvanometer system and the semi-reflecting and semi-transmitting mirror;

the beam splitting prism is arranged between the detection light source and the semi-reflecting and semi-transmitting mirror; the beam splitting prism is used for splitting the reflected detection beam reflected by the original path;

a spot detection assembly opposite the beam splitter prism to collect the reflected detection beam split off from the beam splitter prism;

the upper computer is connected with the light spot detection assembly and is used for controlling the galvanometer to move the focus of the laser beam according to the reflected detection light beam so as to scan a unit area on the bonding layer; the upper computer is also used for controlling the lifting assembly to pull the sucker upwards after the unit area is scanned out, so that the substrate and the wafer are separated at the position of the unit area; the unit area is a circular ring area on the bonding layer, and the center of the circular ring area is overlapped with the center of the wafer.

2. The detection control system of claim 1, wherein the detection beam has a set wavelength, and the transflective lens is a lens that reflects the set wavelength and transmits other wavelengths.

3. The detection control system according to claim 1, wherein a polarizer, a beam expanding and collimating system, a shaping element and an optical isolator are sequentially arranged on the optical path between the laser and the semi-reflecting and semi-transmitting mirror.

4. The detection control system of claim 3, wherein the laser is a fiber laser, and a beam-expanding collimator is further disposed in the optical path between the fiber laser and the polarizer.

5. The detection control system according to claim 1, wherein a conjugate prism is further disposed on an optical path between the beam splitting prism and the spot detection assembly.

6. The inspection control system of claim 1, further comprising a four-axis displacement platform disposed below the stage; four displacement axes in the four-axis displacement platform comprise translation axes in the x direction, the y direction and the z direction and also comprise a rotation axis in the z direction, wherein the z direction is vertical to the supporting end surface of the objective table;

and the upper computer is also connected with the four-axis displacement platform to control the four-axis displacement platform to move.

7. The inspection control system of claim 1 wherein said upper computer is further configured to control said galvanometer system to move a focal point of said laser beam to scan another cell area on said bonding layer based on said reflected inspection beam after said substrate and wafer are separated at said cell area location; the upper computer is also used for controlling the lifting assembly to pull the sucker upwards so as to separate the substrate and the wafer at the position of the other unit area;

and the upper computer separates the substrate and the wafer at the position of the whole bonding layer in sequence according to the control method.

8. The detection control system according to claim 7, wherein the upper computer controls the positions of two unit areas scanned by the focal point of the laser beam in sequence to be adjacent.

9. The detection control system of claim 7, wherein the upper computer is further configured to detect, according to the reflected detection beam, a growth of an explosion point in a cell area scanned by the laser beam;

and the upper computer is also used for adjusting the step of the focal point of the laser beam moved by the galvanometer system between two adjacent explosion points in the same unit area and the step of the focal point of the laser beam in the radial direction of the wafer between the two adjacent unit areas according to the growth condition of the explosion points.

10. The inspection control system of claim 9, wherein said upper computer is further configured to calculate an average E of the growth cross-sectional areas of all the explosion points in a cell region according to the reflected detection beam after the cell region is scanned;

the upper computer is also used for judging whether the area of the growth section with the explosion point in the unit area is not in the range of 90-110% E;

and the upper computer is also used for generating a warning signal for detecting whether the energy of the laser beam generated by the laser is normal or not when the judgment result shows that the area of the growth cross section with the explosion point in the unit area is not in the range of 90-110% E.