CN107378258B - A kind of method and system laser machining wafer - Google Patents
A kind of method and system laser machining wafer Download PDFInfo
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- CN107378258B CN107378258B CN201710575307.8A CN201710575307A CN107378258B CN 107378258 B CN107378258 B CN 107378258B CN 201710575307 A CN201710575307 A CN 201710575307A CN 107378258 B CN107378258 B CN 107378258B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
- B23K26/362—Laser etching
- B23K26/364—Laser etching for making a groove or trench, e.g. for scribing a break initiation groove
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
- B23K26/702—Auxiliary equipment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
- B23K26/702—Auxiliary equipment
- B23K26/705—Beam measuring device
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/36—Electric or electronic devices
- B23K2101/40—Semiconductor devices
Abstract
The present invention provides a kind of method and system for laser machining wafer, which comprises obtains the thickness information of Low-K layers of wafer upper surface；It controls phase control-type liquid crystal on silicon according to thickness information to be modulated laser beam, so that laser beam performs etching wafer upper surface for Low-K layers.The present invention can be measured in real time by the thickness to Low-K layers of wafer upper surface and obtain thickness information, then laser beam is modulated according to the thickness information by phase control-type liquid crystal on silicon, and then realize that the processing of Low-K layers of wafer upper surface obtains customizable shape groove structure by the accurate control to laser beam, and improve working efficiency, laser processing precision and the uniformity for separating wafer of laser processing wafer.
Description
Technical field
The present invention relates to technical field of semiconductors more particularly to a kind of method and system for laser machining wafer.
Background technique
In recent years, with the continuous reduction and the continuous improvement of chip integration of feature sizes of semiconductor devices, metal
The resistance of parasitic capacitance and plain conductor between interconnection line, between multilayer wiring increased dramatically, and result in RC retardation ratio, power consumption
A series of problems, such as increase, limits the development of high-velocity electrons component.After device feature size is less than 90nm, wafer is necessary
Traditional SiO is replaced using advanced low-k materials2Layer (K=3.9~4.2), common Low-K material have Dow Corning Corporation
FOx and porous SiLK material, the low K thin-film material of carbonado series of Applied Materials, Novellus System
FCN+ organic layer of CORAL, the CDO of Intel and NEC Corporation etc..
The use of Low-K material also brings some problems.Whether mechanical strength or adhesiveness, Low-K material is all
It is nothing like SiO2, this proposes challenge to scribing process.Most commonly seen problem is, due to lower machine in scribing processes
Tool intensity and adhesion strength, so that Low-K material sticks in saw blade, this not only lowers the efficiency of scribing, while also bringing
Insulating layer is stripped and generates clast from layer on surface of metal and be diffused into other functional areas etc. seriously affect yield after
Fruit.Laser processing has many advantages, such as that non-contact, precision is high, suitable material range is wide, machining path is flexibly controllable, is for crystalline substance
Circle scribing and the robust solution to solve the above problems.It is reported that the wafer that supplier provides has been strictly required in Apple Inc.
Must be using the technique (that is: Laser Grooving technique) of laser cutting Low-K material, this makes Feng Ce factory to such technique
The demand of technology and equipment significantly increases.Strictly speaking, laser beam not instead of " cutting " Low-K material relies on laser energy
The high temperature melt metal layer and interlayer dielectric layer of generation, such laser cutting generate tool stress very little, because without occurring to divide
The problems such as layer or removing.In addition, Hamamatsu Photonics K. K also invented the technology of " stealth cutting ", this technology is to utilize
There is the laser of transmittance wavelength to focus on inside wafer wafer and form modification layer, then makes wafer along modification layer by external force
It splits for individual chip.Using stealthy cutting technique, chip functions area can be made to avoid clast is generated in scribing processes
At pollution, but when being covered with separation layer or other functional layers above wafer, this will will affect the transmission of laser, to influence
Modify the formation of layer.Therefore, when using stealthy cutting, the materials such as upper surface Low-K layers of laser ablation wafer should be also used first
Material.
But when the plate workpiece of semiconductor wafer has wavy surfaces and in uneven thickness or wafer Working position
When micro-displacement occurs, leads to refractive index when applying laser beam and the failure layer of predetermined depth cannot be formed uniformly, Yi Jiwu
Shape groove structure is precisely cut and be may customize to method to the target position of wafer, and then influences the machining yield of wafer.
Summary of the invention
The method and system of laser processing wafer provided by the invention, can pass through the thickness to Low-K layers of wafer upper surface
Degree is measured in real time and obtains thickness information, and by phase control-type liquid crystal on silicon according to the thickness information to laser beam into
Row modulation, and then realize that the processing of Low-K layers of wafer upper surface obtains customizable shape groove by the accurate control to laser beam
Structure, and improve the working efficiency, laser processing precision and the uniformity for separating wafer of the method.
In a first aspect, the present invention provides a kind of method for laser machining wafer, comprising:
Obtain the thickness information of Low-K layers of wafer upper surface；
It controls phase control-type liquid crystal on silicon according to thickness information to be modulated laser beam, so that laser beam is on wafer
Ow-K layers of Surface L perform etching.
Optionally, the thickness information for obtaining Low-K layers of wafer upper surface includes:
To one detection light beam of Low-K layers of wafer upper surface transmitting；
Obtain the reflected light of detection light beam；
The thickness information of Low-K layers of wafer upper surface is obtained according to the reflected light.
Optionally, the thickness information that Low-K layers of wafer upper surface is obtained according to the reflected light is according to described anti-
Wafer upper surface Low-K layers of the thickness information is calculated in the reflectivity for penetrating light；Wherein,
The thickness of Low-K layers of the reflectivity of the reflected light and wafer upper surface is corresponding, and corresponding relationship, which is stored in, is
In system.
Optionally, described that laser beam is modulated according to thickness information control phase control-type liquid crystal on silicon, so that laser
Light beam performs etching wafer upper surface for Low-K layers, comprising:
The laser parameter of laser beam is adjusted according to thickness information；
Control phase control-type liquid crystal on silicon is modulated laser beam by the laser parameter and forms customization laser light
Beam；
Change the customization laser beam and the relative position of wafer upper surface is recessed to be formed in the wafer upper surface
Slot, to Low-K layers of wafer upper surface realization etching.
Optionally, the laser parameter include Wave-front phase, the angle of divergence, laser irradiation azimuth, beam energy distribution and
One or any combination in laser facula shape.
Optionally, the laser beam that customizes is the hot spot combination or multiple laser sub-light being distributed with specific pattern
The array combination of beam；Wherein,
The hot spot combination with specific pattern distribution include it is rectangular, it is round, diamond shape and customizable shape it is polygonal in one
Kind or any combination:
The array combination of the multiple laser beamlet includes 1*N array or N*M array, or has particular topology pattern
The array combination of distribution, wherein N=2,3 ..., M are more than or equal to 2.
Optionally, before the Wave-front phase for adjusting laser beam according to thickness information, comprising:
Obtain the focus information of laser beam；
Judge whether the laser spot of laser beam astigmatism or distortion occurs according to focus information, if it is not, then keeping swashing
The Wave-front phase of light light beam；If it is, determining the Wave-front phase of laser beam according to the thickness information, and control phase control-type
The Wave-front phase of liquid crystal on silicon modulation laser beam.
Optionally, the method also includes:
The angle of divergence is determined according to thickness information；
It controls phase control-type liquid crystal on silicon and presses the diverging angle modulation laser beam；
Change depth side of the laser spot Low-K layers of wafer upper surface of laser beam by the cooperation with concentrating element
Upward position.
Optionally, the method also includes:
The real-time position information and target position information of wafer are obtained, and obtains laser offset amount；
The laser irradiation azimuth of laser beam is determined according to laser offset amount；
By control phase control-type liquid crystal on silicon modulate laser beam laser irradiation azimuth so that laser beam adjust to
Target position.
Optionally, the laser irradiation azimuth for modulating laser beam by control phase control-type liquid crystal on silicon is to pass through control
Make laser irradiation azimuth of the balzed grating, period loaded on phase control-type liquid crystal on silicon to modulate laser beam.
Second aspect, the present invention provide a kind of system for laser machining wafer, comprising:
Laser, for emitting laser beam；
Beam-expanding collimation element forms collimated light beam for expanding, collimating by the laser beam；
Thickness sensitivity unit, for obtaining the thickness information of Low-K layers of wafer upper surface；
Phase control-type liquid crystal on silicon, for being modulated according to thickness information to collimated light beam；
Unit is laser machined, for performing etching modulated collimated light beam for Low-K layers to wafer upper surface.
Optionally, the system also includes:
First beam splitter for collimated light beam to be divided into machining beams and detection light beam, and will test beam emissions respectively
To Low-K layers of wafer upper surface, machining beams are emitted to phase control-type liquid crystal on silicon；
Determination unit, for obtaining the thickness information of Low-K layers of wafer upper surface according to the reflected light.
Optionally, the system also includes:
Parameter adjustment unit, for adjusting the laser parameter of laser beam according to thickness information.
Optionally, the system also includes:
Beam detection unit, for obtaining the focus information of laser beam；
Second beam splitter for machining beams to be divided at least two beams, and injects phase control-type liquid crystal on silicon, light beam inspection respectively
Survey unit.
Optionally, the laser processing unit includes:
Focusing element array is handled and is emitted on the wafer so that laser for the collimated light beam to be focused
Process wafer upper surface；
Wafer Gripping platform, for clamping the wafer；
Three-axis displacing device, for changing the relative position of the laser beam and wafer upper surface with table upper on wafer
Face forms groove；
Displacement detector for obtaining the real-time position information and target position information of wafer, and obtains laser offset
Amount.
The method and system of laser processing wafer provided in an embodiment of the present invention, which solve, lacks inspection in wafer fabrication processes
Examining system is adjusted it, leads to the precision for reducing laser processing wafer, and the problem that processing groove structure is unstable.This
By being detected and being obtained thickness information to the Low-K layer of wafer upper surface in real time in inventive embodiments, and then being capable of basis
Thickness information reflects the Low-K layer uniformity of the wafer upper surface, wherein wafer upper surface described in the thickness information
The Low-K layers of uniformity are corresponding, and corresponding relationship stores in systems.Then, Low-K of the present embodiment due to wafer upper surface
Layer is in uneven thickness, the quality of the Low-K layer of laser beam processing wafer upper surface is reduced, for example, when using with setting
When the Low-K layer of the laser beam processing wafer upper surface of Energy distribution, since it is poor that the energy absorbed at different-thickness has
It is different, and then form the failure layer of predetermined depth.Therefore, described in the thickness adjustment that Working position as needed is capable of in the present embodiment
The laser parameter of laser beam, so that by the laser beam after modulated when processing Low-K layers of wafer upper surface, it can be accurate
Control processing after groove structure.The present embodiment the method on the one hand can by the thickness real-time detection to Low-K layers,
And to the modulated in real time of laser beam, reach the precision for improving laser processing；On the other hand, additionally it is possible to for different height pair
Laser beam is adjusted, and the groove structure after guaranteeing processing is stablized, and then improves the uniformity of separation wafer.
Detailed description of the invention
Fig. 1 is the flow chart for the method that one embodiment of the invention laser machines wafer；
Fig. 2 is the flow chart for the method that another embodiment of the present invention laser machines wafer；
Fig. 3 is the flow chart for the method that another embodiment of the present invention laser machines wafer；
Fig. 4 is LCOS phase distribution schematic diagram after one embodiment of the invention phase compensation；
Fig. 5 is that the control of load Fresnel Lenses changes focus schematic diagram on one embodiment of the invention LCOS；
Fig. 6 is that one embodiment of the invention difference angle of divergence corresponds to different focus schematic diagrames；
Fig. 7 is the structural schematic diagram for the system that one embodiment of the invention laser machines wafer；
Wherein, 1, laser, 2, optical fiber collimator, 3, the polarizer, 4, beam-expanding collimation element, the 5, second beam splitter, 6, phase
Control type liquid crystal on silicon, 7, concentrating element, 8, adjustable diaphragm, 9, wafer Gripping platform, 10, three-axis displacing device, 11, reflecting mirror,
12, plano-convex lens, 13, detection device, 14, temperature-detecting device, 15, controller, 16, displacement detector, the 21, first beam splitting
Device, 22, Thickness sensitivity unit.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is only
It is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill
Personnel's every other embodiment obtained without making creative work, shall fall within the protection scope of the present invention.
The embodiment of the present invention provides a kind of method for laser machining wafer, as shown in Figure 1, which comprises
S1, the thickness information for obtaining Low-K layers of wafer upper surface；
S2, laser beam is modulated according to thickness information control phase control-type liquid crystal on silicon, so that laser beam is to crystalline substance
Upper surface Low-K layers of circle performs etching.
The method of laser processing wafer provided in an embodiment of the present invention, which has been able to solve in wafer fabrication processes, lacks detection
System is adjusted it, leads to the precision for reducing laser processing wafer, and the problem that processing groove structure is unstable.This hair
By being detected and being obtained thickness information to the Low-K layer of wafer upper surface in real time in bright embodiment, and then believed according to thickness
Breath reflects the Low-K layer uniformity of the wafer upper surface, wherein the Low-K of the thickness information and the wafer upper surface
The layer uniformity is corresponding, and corresponding relationship stores in systems.Then, Low-K thickness of the present embodiment due to wafer upper surface
Degree is uneven, reduces the quality of the Low-K layer of laser beam processing wafer upper surface, for example, having setting energy when using
When the Low-K layer of the laser beam processing wafer upper surface of distribution, due to, the energy absorbed at different-thickness has difference,
And then form the failure layer of predetermined depth.Therefore, the thickness adjustment that Working position as needed is capable of in the present embodiment is described sharp
The laser parameter of light light beam, so that by the laser beam after modulated when processing Low-K layers of wafer upper surface, it can be accurate
Groove structure after control processing.The present embodiment the method on the one hand can by the thickness real-time detection to Low-K layers, and
To the modulated in real time of laser beam, reach the precision for improving laser processing；On the other hand, additionally it is possible to for different height to sharp
Light light beam is adjusted, and the groove structure after guaranteeing processing is stablized, and then improves the uniformity of separation wafer.
Wherein, as shown in figure 4, phase control-type liquid crystal on silicon used in the present embodiment is selected as the phase control-type after phase compensation
Liquid crystal on silicon.LCOS display is a kind of " interlayer structure " --- the silicon substrate egative film comprising CMOS technology and the glass for being coated with ito film
Glass piece " folder " (encapsulation) one layer of liquid crystal material.By the way that video conversion circuit, line-scanning drive circuit and picture element matrix are produced on
In silicon base, and ito film is used as public electrode, the overturning of liquid crystal material is driven by the electric signal of varying strength, to incident light
The light intensity redistribution of emergent light is realized in the effect for generating phase delay.Specifically, by loading phase hologram hum pattern, adjustment
The electric signal size of each pixel of LCOS carries out the processing of phase delay to incident light, the final light intensity for realizing reflected light, beam splitting,
A series of form of electromagnetic transmissions such as shaping.Due to the complex manufacturing technology of device, result in LCOS in the prevalence of
The problem of optic response homogeneity deficiency, this has seriously affected the precision and light diffraction efficiency of Beam Control.Therefore, such as Fig. 4 institute
Show, selected LCOS is device after phase compensation optimization in the present embodiment, i.e., by " liquid crystal layer spatial distribution it is uneven
Property " analyze the influence for determining light control system precision and light diffraction efficiency；It is " empty that device liquid crystal layer is improved by optical compensation method again
Between phase change " homogeneity, the optimization of the final precision for realizing light control system and light diffraction efficiency.
Meanwhile phase type Fresnel lens figure is realized by computer in the present embodiment and is loaded on LCOS device, it is real
Modern times replace the process of conventional lenses, the phase type Fresnel lens figure of a width particular focal length are constructed, as shown in figure 5, Fresnel is saturating
The effect of mirror is to replace the function of ordinary lens in conventional correlator, uses common convex lens figure, it may appear that corner is dimmed, mould
The phenomenon that paste, this is because the refraction of light only occurs in the interface of medium, convex lens sheet is thicker, light straightline propagation in glass
Part can make light attenuation.If the part of straightline propagation can be removed, only retains the curved surface reflected, just can save
Lot of materials reaches identical spotlight effect simultaneously.Fresnel lens is exactly using this principle.Fresnel Lenses seems
As a piece of glass for having countless multiple concentric circles lines (i.e. Fresnel zone), it can but achieve the effect that convex lens, if projection light
Source is directional light, is able to maintain the consistent of image brightness throughout after convergence projection, is conducive to improve processing effect, intensification pair in this way
The control of flute profile.
When loading phase type Fresnel lens figure on LCOS, the angle of divergence of laser changes, therefore cooperates processing institute
The accurate control of focus point may be implemented with plano-convex lens, as shown in Figure 6.It is as follows according to the focusing formula of lens:
1/f=1/u+1/v
F is the focal length of lens, this is the inherently attribute of the lens of selection.U is object distance, is object distance lens light
The distance of heart O point.V is image distance, is the later image distance of imaging with a distance from optical center of lens O point.Therefore, when the angle of divergence of laser changes
Becoming, corresponding object distance also changes, and the focal length of lens is constant, it changes so as to cause image distance, that is, focus
It is mobile.As shown in fig. 6, focus also can be moved up slowly therewith when laser beam divergence is assembled since collimating status.Then
It when laser is smaller and smaller by the effect focal length of Fresnel lens, and converges between LCOS and plano-convex lens, at this moment focus is opened
Begin becoming smaller and slowly move down therewith with Fresnel lens focal length.
Therefore, the phase control-type liquid crystal on silicon can realize the micro-adjustment to laser beam, Jin Erti according to thickness information
The high accuracy of laser processing.
In conclusion the present embodiment can be measured in real time and be obtained by the thickness to Low-K layers of wafer upper surface
Thickness information, and laser beam is modulated according to the thickness information by phase control-type liquid crystal on silicon, and then by sharp
The accurate control of light light beam realizes that the processing of Low-K layers of wafer upper surface obtains customizable shape groove structure, and improves the side
Working efficiency, laser processing precision and the uniformity for separating wafer of method.
Optionally, as shown in Figures 2 and 3, the thickness information for obtaining Low-K layers of wafer upper surface includes:
To one detection light beam of Low-K layers of wafer upper surface transmitting；
Obtain the reflected light of detection light beam；
The thickness information of Low-K layers of wafer upper surface is obtained according to the reflected light.
Specifically, Low-K layers of wafer upper surface is transparent material in the present embodiment, therefore, using detection in the present embodiment
The reflection case that Low-K layers of wafer upper surface realizes the detection to wafer upper surface Low-K thickness degree, specifically on wafer
The weaker detection light beam of ow-K layers of Surface L one light intensity of transmitting, and after described wafer upper surface Low-K layers reflection, it is anti-to form one
Light is penetrated, and by being calculated the reflected light and being obtained the wafer upper surface Low-K layers of corresponding thickness.Wherein, described
The thickness that Low-K layers of wafer upper surface has an impact range, angle, the light intensity etc. to reflected light, therefore, can pass through the reflection
Light obtains wafer upper surface Low-K layers of the thickness.For example, the range of the reflected light increases, laser when thickness increases
Energy loss increases.Therefore the light intensity energy value and angle measured by four-quadrant power meter changes therewith, according to
The difference of energy variation and the offset of angle can extrapolate the thickness of Low-K material.
Optionally, the thickness information that Low-K layers of wafer upper surface is obtained according to the reflected light is according to described anti-
Wafer upper surface Low-K layers of the thickness information is calculated in the reflectivity for penetrating light；Wherein,
The thickness of Low-K layers of the reflectivity of the reflected light and wafer upper surface is corresponding, and corresponding relationship, which is stored in, is
In system.
Optionally, described that laser beam is modulated according to thickness information control phase control-type liquid crystal on silicon, so that laser
Light beam performs etching wafer upper surface for Low-K layers, comprising:
The laser parameter of laser beam is adjusted according to thickness information；
Control phase control-type liquid crystal on silicon is modulated laser beam by the laser parameter and forms customization laser light
Beam；
Change the customization laser beam and the relative position of wafer upper surface is recessed to be formed in the wafer upper surface
Slot, to Low-K layers of wafer upper surface realization etching.
Optionally, the laser parameter include Wave-front phase, the angle of divergence, laser irradiation azimuth, beam energy distribution and
One or any combination in laser facula shape.
Optionally, the laser beam that customizes is the hot spot combination or multiple laser sub-light being distributed with specific pattern
The array combination of beam；Wherein,
The hot spot combination with specific pattern distribution include it is rectangular, it is round, diamond shape and customizable shape it is polygonal in one
Kind or any combination:
The array combination of the multiple laser beamlet includes 1*N array or N*M array, or has particular topology pattern
The array combination of distribution, wherein N=2,3 ..., M are more than or equal to 2.
Optionally, before the Wave-front phase for adjusting laser beam according to thickness information, comprising:
Obtain the focus information of laser beam；
Judge whether the laser spot of laser beam astigmatism or distortion occurs according to focus information, if it is not, then keeping swashing
The Wave-front phase of light light beam；If it is, determining the Wave-front phase of laser beam according to the thickness information, and control phase control-type
The Wave-front phase of liquid crystal on silicon modulation laser beam.
Optionally, the method also includes:
The angle of divergence is determined according to thickness information；
It controls phase control-type liquid crystal on silicon and adjusts laser beam by the angle of divergence；
Change depth side of the laser spot Low-K layers of wafer upper surface of laser beam by the cooperation with concentrating element
Upward position.
Optionally, the method also includes:
The real-time position information and target position information of wafer are obtained, and obtains laser offset amount；
The laser irradiation azimuth of laser beam is determined according to laser offset amount；
By control phase control-type liquid crystal on silicon modulate laser beam laser irradiation azimuth so that laser beam adjust to
Target position.
Optionally, the laser irradiation azimuth for modulating laser beam by control phase control-type liquid crystal on silicon is to pass through control
Make laser irradiation azimuth of the balzed grating, period loaded on phase control-type liquid crystal on silicon to modulate laser beam.
Optionally, laser beam is modulated according to thickness information control phase control-type liquid crystal on silicon, so that laser light
Before beam performs etching Low-K layers of wafer upper surface, further includes:
Detect the environment temperature of phase control-type liquid crystal on silicon 6；
Receive the set environment temperature of phase control-type liquid crystal on silicon 6；
It is whether consistent with set environment temperature to judge environment temperature, if it is, keeping the environment temperature；If not,
Then it is adjusted to set environment temperature.
Specifically, since optic response of the environment temperature to phase control-type liquid crystal on silicon 6 has an impact in the present embodiment,
It, need to be to phase control-type silicon substrate liquid in the present embodiment before laser beam is micro-adjusted using the phase control-type liquid crystal on silicon 6
The environment temperature that the environment temperature of crystalline substance 6 is detected, and is adjusted to setting enables phase control-type liquid crystal on silicon 6 in optimal ring
Laser beam is micro-adjusted at a temperature of border.Meanwhile set environment temperature is corresponding with phase control-type liquid crystal on silicon 6, corresponds to
Relationship is stored in controller 15.It is when phase control-type liquid crystal on silicon 6 is the phase control-type liquid crystal on silicon 6 of reflective liquid crystal, then described
Set environment temperature is corresponding with phase control-type liquid crystal on silicon, allow phase control-type liquid crystal on silicon under optimal environment temperature into
Row work, thus the optic response of further phase control-type liquid crystal on silicon.Meanwhile improve the method in predetermined cuts road
Interior accurate etching.
The embodiment of the present invention also provides a kind of system for laser machining wafer, as shown in fig. 7, described device includes:
Laser, for emitting laser beam；
Beam-expanding collimation element forms collimated light beam for expanding, collimating by the laser beam；
Thickness sensitivity unit, for obtaining the thickness information of Low-K layers of wafer upper surface；
Phase control-type liquid crystal on silicon, for being modulated according to thickness information to collimated light beam；
Unit is laser machined, for performing etching modulated collimated light beam for Low-K layers to wafer upper surface.
The laser beam that the system of laser processing wafer provided in an embodiment of the present invention is emitted by laser, through fiber optic collimator
Device 2, the polarizer 3, beam-expanding collimation element 4 form collimated light beam, and collimated light beam is divided into machining beams and detection light by beam splitter 5
Beam, and will test light beam inclination transmitting to described wafer upper surface Low-K layers and reflex to Thickness sensitivity unit, and then to wafer
Upper surface Low-K layers of thickness is measured in real time and obtains thickness information；Machining beams are emitted to phase control-type liquid crystal on silicon
And laser beam is modulated according to the thickness information by phase control-type liquid crystal on silicon, finally will be modulated after laser light
Beam emits to laser processing unit to process Low-K layers of wafer upper surface, and then real by the accurate control to laser beam
The processing of Low-K layer of existing wafer upper surface obtains may customize shape groove structure, and improve the working efficiency of the method, laser adds
Work precision and the uniformity for separating wafer.
Alternatively, a machining beams and a detection light beam can also be emitted respectively in the present embodiment by laser, and respectively
Light beam inclination transmitting be will test to described wafer upper surface Low-K layers and reflex to Thickness sensitivity unit, machining beams are emitted
Laser beam is modulated according to the thickness information to phase control-type liquid crystal on silicon and by phase control-type liquid crystal on silicon.
In conclusion system described in the present embodiment can be real-time to the thickness of Low-K layers of wafer upper surface by realizing
Real-time thickness information is detected and obtained, laser beam is modulated according to real-time thickness information, and uses modulated laser
Light beam processes wafer upper surface for Low-K layers, enables the system that wafer upper surface is processed and can be determined for Low-K layers
Shape groove structure, and improve the machining accuracy of the system.
Optionally, the system also includes:
First beam splitter for collimated light beam to be divided into machining beams and detection light beam, and will test beam emissions respectively
To Low-K layers of wafer upper surface, machining beams are emitted to phase control-type liquid crystal on silicon；
Determination unit, for obtaining the thickness information of Low-K layers of wafer upper surface according to the reflected light.
Optionally, the system also includes:
Parameter adjustment unit, for adjusting the laser parameter of laser beam according to thickness information.
Optionally, the system also includes:
Beam detection unit, for obtaining the focus information of laser beam；
Second beam splitter for machining beams to be divided at least two beams, and injects phase control-type liquid crystal on silicon, light beam inspection respectively
Survey unit.
Specifically, machining beams are divided at least two beams by the second beam splitter in the present embodiment, wherein a branch of inject instead
Penetrate mirror 11 and reflex to the beam detection unit, the beam detection unit includes plano-convex lens and detection device, mainly by
The light beam reflected through reflecting mirror 11 is focused to detection device and realizes detection by plano-convex lens.
Optionally, the laser processing unit includes:
Focusing element array is handled and is emitted on the wafer so that laser for the collimated light beam to be focused
Process wafer upper surface；
Wafer Gripping platform, for clamping the wafer；
Three-axis displacing device, for changing the relative position of the laser beam and wafer upper surface with table upper on wafer
Face forms groove；
Displacement detector for obtaining the real-time position information and target position information of wafer, and obtains laser offset
Amount.
Optionally, the system also includes:
Controller, including determination unit, parameter adjustment unit, and for realizing the control to system various pieces.
The controller can also be used in the laser irradiation azimuth that laser beam is determined according to laser offset amount.
The device of the present embodiment can be used for executing the technical solution of above method embodiment, realization principle and technology
Effect is similar, and details are not described herein again.
The above description is merely a specific embodiment, but scope of protection of the present invention is not limited thereto, any
Within the technical scope of the present disclosure, any changes or substitutions that can be easily thought of by those familiar with the art, all answers
It is included within the scope of the present invention.Therefore, protection scope of the present invention should be subject to the protection scope in claims.
Claims (13)
1. a kind of method for laser machining wafer characterized by comprising
Obtain the thickness information of Low-K layers of wafer upper surface；
It controls phase control-type liquid crystal on silicon according to thickness information to be modulated laser beam, so that laser beam is to wafer upper surface
Low-K layers perform etching；Wherein,
It is described that laser beam is modulated according to thickness information control phase control-type liquid crystal on silicon, so that laser beam is on wafer
Ow-K layers of Surface L perform etching, comprising:
The laser parameter of laser beam is adjusted according to thickness information；
Control phase control-type liquid crystal on silicon is modulated laser beam by the laser parameter and forms customization laser beam；
Change the relative position of the customization laser beam and wafer upper surface to form groove in the wafer upper surface, uses
To Low-K layers of wafer upper surface realization etching；
Also, it is described to customize the battle array that laser beam is the hot spot combination or multiple laser beamlet that are distributed with specific pattern
Column combination.
2. the method according to claim 1, wherein the thickness information for obtaining Low-K layers of wafer upper surface
Include:
To one detection light beam of Low-K layers of wafer upper surface transmitting；
Obtain the reflected light of detection light beam；
The thickness information of Low-K layers of wafer upper surface is obtained according to the reflected light.
3. according to the method described in claim 2, it is characterized in that, described obtain wafer upper surface Low- according to the reflected light
K layers of thickness information is that wafer upper surface Low-K layers of the thickness information is calculated according to the reflectivity of the reflected light；
Wherein,
The thickness of Low-K layers of the reflectivity of the reflected light and wafer upper surface is corresponding, and corresponding relationship stores in systems.
4. according to the method described in claim 3, it is characterized in that, the laser parameter includes Wave-front phase, the angle of divergence, laser
One or any combination in irradiation azimuth, beam energy distribution and laser facula shape.
5. according to the method described in claim 4, it is characterized in that, the customization laser beam is to be distributed with specific pattern
Hot spot combination or multiple laser beamlet array combination；Wherein,
The hot spot combination with specific pattern distribution include it is rectangular, it is round, it is a kind of in diamond shape and customizable type polygon or
Person's any combination:
The array combination of the multiple laser beamlet includes 1*N array or M*N array, or has the distribution of particular topology pattern
Array combination, wherein N=2,3 ..., M be more than or equal to 2.
6. method according to claim 4 or 5, which is characterized in that in the wavefront for adjusting laser beam according to thickness information
Before phase, comprising:
Obtain the focus information of laser beam；
Judge whether the laser spot of laser beam astigmatism or distortion occurs according to focus information, if it is not, then keeping laser light
The Wave-front phase of beam；If it is, determining the Wave-front phase of laser beam according to the thickness information, and control phase control-type silicon substrate
The Wave-front phase of liquid crystal modulation laser beam.
7. method according to claim 4 or 5, which is characterized in that the method also includes:
The angle of divergence is determined according to thickness information；
It controls phase control-type liquid crystal on silicon and presses the diverging angle modulation laser beam；
Change the laser spot of laser beam on the depth direction of Low-K layers of wafer upper surface by the cooperation with concentrating element
Position.
8. -5 any method according to claim 1, which is characterized in that the method also includes:
The real-time position information and target position information of wafer are obtained, and obtains laser offset amount；
The laser irradiation azimuth of laser beam is determined according to laser offset amount；
The laser irradiation azimuth that laser beam is modulated by control phase control-type liquid crystal on silicon, so that laser beam is adjusted to target
Position.
9. according to the method described in claim 8, it is characterized in that, described modulate laser light by control phase control-type liquid crystal on silicon
The laser irradiation azimuth of beam is by controlling the balzed grating, period loaded on phase control-type liquid crystal on silicon to modulate laser
The laser irradiation azimuth of light beam.
10. a kind of system for laser machining wafer characterized by comprising
Laser, for emitting laser beam；
Beam-expanding collimation element forms collimated light beam for expanding, collimating by the laser beam；
Thickness sensitivity unit, for obtaining the thickness information of Low-K layers of wafer upper surface；
Parameter adjustment unit, for adjusting the laser parameter of laser beam according to thickness information；
Phase control-type liquid crystal on silicon for being modulated according to thickness information to collimated light beam, and also controls phase control-type silicon substrate liquid
Crystalline substance is modulated to laser beam by the laser parameter and is formed customization laser beam, and the customization laser beam is tool
The array combination of the hot spot combination or multiple laser beamlet that there is specific pattern to be distributed；
Unit is laser machined, for performing etching modulated collimated light beam for Low-K layers to wafer upper surface；And change institute
The relative position for customizing laser beam and wafer upper surface is stated to form groove in the wafer upper surface, to on wafer
Ow-K layers of realization etching of Surface L.
11. system according to claim 10, which is characterized in that the system also includes:
First beam splitter for collimated light beam to be divided into machining beams and detection light beam, and will test beam emissions to crystalline substance respectively
Upper surface Low-K layers of circle, machining beams are emitted to phase control-type liquid crystal on silicon；
Determination unit, for obtaining the thickness information of Low-K layers of wafer upper surface according to reflected light.
12. system described in 0 or 11 according to claim 1, which is characterized in that the system also includes:
Beam detection unit, for obtaining the focus information of laser beam；
Second beam splitter for machining beams to be divided at least two beams, and injects phase control-type liquid crystal on silicon, beam detection list respectively
Member.
13. system described in 0 or 11 according to claim 1, which is characterized in that the laser processing unit includes:
Focusing element array is handled and is emitted on the wafer so as to laser machine for the collimated light beam to be focused
Wafer upper surface；
Wafer Gripping platform, for clamping the wafer；
Three-axis displacing device, for changing the relative position of the laser beam and wafer upper surface with the upper surface shape on wafer
At groove；
Displacement detector for obtaining the real-time position information and target position information of wafer, and obtains laser offset amount.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04172192A (en) * | 1990-11-07 | 1992-06-19 | Nec Corp | Laser beam machine |
| CN102896421A (en) * | 2012-07-30 | 2013-01-30 | 沈明亚 | LCOS (liquid crystal on silicon) laser micromachining system and laser micromachining method |
| JP2013230477A (en) * | 2012-04-27 | 2013-11-14 | Disco Corp | Laser machining apparatus and laser machining method |
| JP2013230478A (en) * | 2012-04-27 | 2013-11-14 | Disco Corp | Laser machining apparatus and laser machining method |
| CN204195071U (en) * | 2014-11-10 | 2015-03-11 | 苏州大学 | A kind of laser drilling device |
| CN205817104U (en) * | 2016-06-28 | 2016-12-21 | 深圳英诺激光科技有限公司 | A kind of laser process equipment removing thin film or coating |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106938370B (en) * | 2015-12-30 | 2019-12-24 | 上海微电子装备（集团）股份有限公司 | Laser processing system and method |
-
2017
- 2017-07-14 CN CN201710575307.8A patent/CN107378258B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04172192A (en) * | 1990-11-07 | 1992-06-19 | Nec Corp | Laser beam machine |
| JP2013230477A (en) * | 2012-04-27 | 2013-11-14 | Disco Corp | Laser machining apparatus and laser machining method |
| JP2013230478A (en) * | 2012-04-27 | 2013-11-14 | Disco Corp | Laser machining apparatus and laser machining method |
| CN102896421A (en) * | 2012-07-30 | 2013-01-30 | 沈明亚 | LCOS (liquid crystal on silicon) laser micromachining system and laser micromachining method |
| CN204195071U (en) * | 2014-11-10 | 2015-03-11 | 苏州大学 | A kind of laser drilling device |
| CN205817104U (en) * | 2016-06-28 | 2016-12-21 | 深圳英诺激光科技有限公司 | A kind of laser process equipment removing thin film or coating |
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