Background technology
Recently, along with the high speed of ICT, integrated, lightweight, and quickened to have the exploitation of the signal conditioning package of very fast information processing capability, thus, the discernible technological development by the information display device of the interface function of the information after the high speed processing (below, be called " display equipment ") of the person that has the display operation occupies important proportion in industrial community.
Common CRT (Cathode Ray Tube: cathode tube) be the display equipment that always uses in whole 20th century, do not associate and begin to 21 century for 20 end of the centurys, can't satisfy the even more important portable display equipment of using, or have bottleneck satisfying aspect the requiring of maximization, high resolving power, small volume etc.
Therefore, realities of the day are, LCD (the Liquid Crystal Display: liquid-crystal display) that breaks away from existing C RT (Cathode Ray Tube) mode, PDP (Plasma Display Panel: plasma display), thin film transistor) etc. (Thin Film Transistor: the display equipment of multiple mode is widely used OLED (Organic Light Emitting Device: organic luminescent device) to TFT, OEP (Organic Electroluminescence Panel: organic electroluminescence panel) also entered the specific implementation stage.
Such display equipment must can use the visual signalling of utilizing light, so must contain transparent material, uses glass in normal circumstances.
For example, under the situation of LCD (Liquid Crystal Display), after having injected liquid crystal between two transparent glass substrates, the transparency carrier that injects liquid crystal is divided into very trickle zone, and utilize electric field to regulate the arrangement of liquid crystal to each zone, make via the arrangement of liquid crystal the light that sends from twinkler by or it is blocked, perhaps regulate light quantity, after light has passed through transparency carrier, pass through rgb pixel on one side, light is filtered into each specified color on one side, can comes vision ground to show information with the form of inlaying like this.
In addition, under the situation of PDP (Plasma Display Panel), in two transparency carriers, arrange and to produce CCP (Charge-Coupled Plasma, the electric charge coupled plasma) very trickle unit, electrically regulate each unit, only produce plasma body in the part of hope, the light of the ultra-violet region that the twinkler that is attached to the back side of the place ahead glass like this sends when being absorbed in plasma generation, and show with the mode that the light that switches to visible rays the transmits information of carrying out.
The substrate that is used for such display equipment mainly uses the glass substrate with prescribed strength, but nearest tendency is to use at first to form a plurality of display equipments simultaneously on the very large glass mother substrate of size, cut out the technology that the size of hope is finally finished then, this technology is judged as economically and is favourable on the time, therefore begins to just come onto stage.
Using in above-mentioned cutting and separating process is the diamond cutting cutting-tool engineering the earliest, the most widely.According to utilizing adamantine method can be divided into following dual mode: promptly adopt the diamond blade of high speed rotating on substrate, to form section (dicing) mode of cutting with groove and cutting; Perhaps on substrate, form cutting and use groove, and on the thickness direction of substrate, form the line mode of crackle by the tracing wheel (scribing wheel) that constitutes by diamond.
But there is following shortcoming under this situation, promptly because cutting process is equivalent to the last of whole production process, so if produced cutting, crackle or damage to the direction different with target direction in cutting, then loss is very big.
The reason of the damage different with target has multiplely like this, but commonly because when the mechanical force that applies diamond cutter etc. was cut, cut surface was unsmooth, stress concentration is not by the part of fine cut.
Promptly, when utilizing sharp-pointed blade to apply mechanical force to mark line of cut, because glass is the amorphousness material, so inevitable groove that all is formed with the very irregular shape that does not stay the definite shape track on depth direction and the range direction, when it is exerted pressure, certainly can produce the cut direction situation different, owing to trickle part or fragmentation produce the part damage with the direction of hope.
In addition, diamond blade or tracing wheel use the material and the life-span weak point of high price, so the problem that manufacturing cost rises also is regarded as shortcoming.
In order to remedy such shortcoming, the mode that exploitation has recently used irradiating laser to cut.Though it is different slightly according to wishing that the material processed characteristic has that the laser that uses for example is carbon dioxide laser, Nd:YAG laser etc., basic operating principle is principle as described below.
Fig. 1 is the figure that briefly represents the cutter for substrate that utilizes laser of prior art.
With reference to Fig. 1, cutting path illuminating laser beam 1 along glass mother substrate 2, cutting path to illuminating laser beam 1 in substrate 2 heats rapidly, on the cutting path of heating rapidly, spray the cooling body 3 of temperature with the Heating temperature that significantly is lower than substrate 2, by by the rapid expansion of substrate 2 and shrink the thermal stresses that produces, along cutting path cutting substrate 2.
Also proposed other various technology in addition, formed the mode of small groove as before illuminating laser beam 1, adopting diamond cutter earlier; The mode of after illuminating laser beam 1, using diamond cutter to rule along the path of illuminating laser beam 1 with appending; Or illuminating laser beam 1 and shower cooling body 3 in advance, the mode of illuminating laser beam 1 etc. again afterwards.
But recently, along with the maximization of display equipment, and have the area of plane of glass mother substrate and the tendency that thickness increases gradually, therefore, the glass substrate of current use has the thickness about about 0.7mm.In order once just to cut off the glass substrate of this thickness, and must the very high-octane laser beam of irradiation.
In the case, temperature contrast is excessive when utilizing cooling body to carry out quick cooling, thus crack therefrom and damage, thus might bring difficulty to making.In addition, owing to the attack ripple that dashes that injects the material internal that stronger energy occurs also is to make the inner major cause that produces undesirable crackle.
In addition, just because of be the cutting mode that utilizes laser beam, so may exist in unessential other parameters in the mechanical mode, this fragment but when illuminating laser beam, on machined surface, melts and applied the fragment that is produced in the material (debris), so may bring bad influence to the focal length of the laser beam of high precision coupling and direction of illumination etc.
Summary of the invention
The present invention makes in order to solve problem point, therefore cutter for substrate that utilizes the ultra-short pulse laser bundle and the cutting method thereof that provides as follows be provided, promptly, can utilize ultra-short pulse laser from femtosecond FS to psec PS, with according to the purposes of indicating meter and characteristic and the substrate properties of different slightly glass or transparent material is irrelevant, reduce complicated front/rear operation to greatest extent, only utilize simple operation just can realize rapid and high-precision cutting processing, prevent undesirable cutting, crackle and damage, make the fraction defective minimization.
To achieve these goals, the cutter for substrate that utilizes the ultra-short pulse laser bundle that relates to first embodiment of the invention has: the laser generation unit, and it is used to produce the ultra-short pulse laser bundle; And focal adjustments unit, it is used to regulate so that above-mentioned ultra-short pulse laser bundle is focused in the inside of the substrate that will cut, focus in the inside of aforesaid substrate by making above-mentioned ultra-short pulse laser bundle, and shine along the cutting path of hope, come direct internal to become the silk phenomenon, form slot in the inside of aforesaid substrate.
Preferably above-mentioned ultra-short pulse laser bundle has the pulse width of femtosecond (FS) to psec (PS).
Preferably above-mentioned focal adjustments unit is being regulated so that above-mentioned ultra-short pulse laser bundle is focused in the inside of aforesaid substrate by the cutting path of hope and after having formed slot or simultaneously, regulate so that above-mentioned ultra-short pulse laser bundle is focused on same cutting path and form slot once more, perhaps regulate once more to focus in the inside of aforesaid substrate, and to form slot doubly in the upper surface of aforesaid substrate and at the upper surface of aforesaid substrate.
In addition, relate to the cutter for substrate that utilizes the ultra-short pulse laser bundle of the present invention the 2nd embodiment, have: the laser generation unit, it is used to produce the ultra-short pulse laser bundle; And focal adjustments unit, its be used to regulate so that above-mentioned ultra-short pulse laser bundle focus in the be separated by gas cloud at certain interval of the lower surface of the substrate that will cut, make above-mentioned ultra-short pulse laser bundle focus in the be separated by gas cloud at certain interval and shine of the lower surface of aforesaid substrate along the cutting path of hope, utilize the light that on the boundary surface of the lower surface of aforesaid substrate and gas cloud, reflects to form the 1st slot of certain depth at the upper surface position of aforesaid substrate thus, the light of the air molecule that utilization produces at the focus place of above-mentioned ultra-short pulse laser bundle and the reflection of the place, border of plasmasphere is at the 2nd slot of the position formation certain depth that is located along the same line with above-mentioned the 1st slot of the lower surface of aforesaid substrate.
Preferably above-mentioned ultra-short pulse laser bundle has the pulse width of femtosecond (FS) to psec (PS).
Preferably aforesaid substrate can be made of the insulativity substrate with or plural at least multilayered structure.
Preferably utilize the cutter for substrate of ultra-short pulse laser bundle also can have convergence unit, it is configured between above-mentioned laser generation unit and the aforesaid substrate, is used for above-mentioned ultra-short pulse laser bundle is focused on the focal position of hope.
Preferably above-mentioned convergence unit can comprise at least one lens with numerical aperture (NA) of about 0.3~0.7.
Preferably utilize the cutter for substrate of ultra-short pulse laser bundle also can have: driver element, itself and above-mentioned focal adjustments unit link, be used to transmit the motivating force of regulation, so that above-mentioned focal adjustments unit moves along the cutting path of the hope speed with hope.
Preferably can utilize at least one speculum or interferometer, above-mentioned ultra-short pulse laser bundle is moved along the cutting path of hope.
Preferably utilize the cutter for substrate of ultra-short pulse laser bundle also can have monitoring unit, it regulates multiplying power with consistent with the focus of above-mentioned ultra-short pulse laser bundle, the user can directly specify the focal position of the ultra-short pulse laser bundle of wishing while observing picture before processing, can confirm the operation process by picture in real time when cutting action.
Preferably utilize the cutter for substrate of ultra-short pulse laser bundle also can have auxiliary cutter unit, its be used for above-mentioned slot consistent location on apply certain pressure so that can cut along above-mentioned slot.
Preferably utilize the cutter for substrate of ultra-short pulse laser bundle also can have control unit, it is used to bear the input and output and focus, the unitary action of above-mentioned focal adjustments and the speed that comprise above-mentioned ultra-short pulse laser bundle and controls in interior integral body.
In addition, the method for dividing substrate that utilizes the ultra-short pulse laser bundle that relates to the present invention the 3rd embodiment has following step: (a) pre-prepd substrate is fixed on the step on the certain location; (b) regulate so that the ultra-short pulse laser bundle is focused in the step of the inside of aforesaid substrate; And (c) focus in the ultra-short pulse laser bundle of the inside of aforesaid substrate along the irradiation of the cutting path of hope, form the step of slot in the inside of aforesaid substrate.
Preferably above-mentioned ultra-short pulse laser bundle has the pulse width of femtosecond (FS) to psec (PS).
Preferably after above-mentioned steps (c) or also can have following steps simultaneously: regulate so that above-mentioned ultra-short pulse laser bundle is focused in the upper surface of aforesaid substrate, focus in the ultra-short pulse laser bundle of the upper surface of aforesaid substrate along the irradiation of same cutting path then, form slot at the upper surface of aforesaid substrate.
Preferably also can have following steps afterwards: regulate so that above-mentioned ultra-short pulse laser Shu Zaici focuses in the inside of aforesaid substrate in above-mentioned steps (c), shine along same cutting path then, form slot doubly in the inside of aforesaid substrate.
In addition, the method for dividing substrate that utilizes the ultra-short pulse laser bundle that relates to the present invention the 4th embodiment has following step: (a ') is fixed on step on the certain location with pre-prepd substrate; (b ') regulate so that the ultra-short pulse laser bundle focus in the be separated by step of gas cloud at certain interval of the lower surface of aforesaid substrate; And (c ') focus in the ultra-short pulse laser bundle of above-mentioned gas cloud along the cutting path irradiation of hope, the step that forms the slot of certain depth simultaneously at the upper surface and the lower surface of aforesaid substrate.
Preferably also can have following steps afterwards or simultaneously: regulate so that above-mentioned ultra-short pulse laser bundle is focused in the inside of aforesaid substrate in above-mentioned steps (c '), shine along same cutting path then, form slot in the inside of aforesaid substrate.
Preferably above-mentioned ultra-short pulse laser bundle has the pulse width of femtosecond (FS) to psec (PS).
According to cutter for substrate and the cutting method thereof of utilizing the ultra-short pulse laser bundle of the present invention that as above illustrates, about the glass substrate that in various display equipments, uses, utilization produces the ultra-short pulse laser bundle of thermal damage, physical abuse hardly to the substrate of glass or transparent material, obviously has following advantage, that is, can be with the substrate of very high precision, the crackle of wishing invariably or damage ground general glass of cutting and transparent material.
In addition according to the present invention, can make cut surface not have convex-concave or irregular, and can avoid thermal damage, physical abuse and optical damage on the material, different with existing mode, position with incident ultra-short pulse laser bundle is the outside focusing of benchmark to the substrate back, have thus and can prevent various undesirable damages in advance, and the fragment that produces when removing by cutting processing and the advantage of obstruction on the operation that causes.
In addition, according to the present invention, suitably utilize the distinctive self-focusing of femtosecond laser and in the effect of the light of each face reflection, irradiation by a ultra-short pulse laser bundle, simultaneously upper surface of base plate on the ultra-short pulse laser beam path and lower surface are impacted, form two line, can further improve the accuracy of cutting thus, utilize femtosecond laser and do not need cooling body, need not other deleterious pharmaceutical chemicalss and complicated step process, the only advantage that just can cut accurately by simple operation thereby have.
Embodiment
Below, with reference to accompanying drawing embodiments of the invention are described in detail.But, below illustrative embodiments of the invention deformable be various other forms, scope of the present invention is not defined to the embodiment of following explanation.Embodiments of the invention are in order to illustrate more completely that to the people with the common knowledge in present technique field the present invention provides.
(the 1st embodiment)
Fig. 2 is a whole frame assumption diagram of briefly representing the cutter for substrate that utilizes the ultra-short pulse laser bundle of the present invention the 1st embodiment.
With reference to Fig. 2, the cutter for substrate that utilizes the ultra-short pulse laser bundle of the present invention the 1st embodiment roughly possesses: the laser generation module 100 that produces the ultra-short pulse laser bundle; And the focal adjustments module 200 of the focus of the ultra-short pulse laser bundle that produces by laser generation module 100 of fixing base S (with reference to Fig. 3 to Fig. 5) and free adjustment etc.
Here, above-mentioned ultra-short pulse laser bundle has for example femtosecond FS (10
-15Second)~psec PS (10
-12Second) pulse of (about preferably about 50FS~3PS).
Aforesaid substrate S (for example can be used for various display equipments, LCD, PDP, OLED, FED etc.) in, preferred utilize have one or plural at least multilayered structure insulated substrate (for example, glass substrate, silicon substrate or sapphire substrate etc.) come specific implementation, but be not limited to this, for example, also can utilize various substrate of general glass and transparent material to come specific implementation.
In addition, for fixing base S stably, and focal adjustments module 200 preferably has microscope carrier (not shown), this focal adjustments module 200 has following function, that is, regulate so that focus in the inside of substrate S (being preferably inboard central part) by the ultra-short pulse laser bundle of laser generation module 100 generations.
Such focal adjustments module 200 preferably constitutes, fixing base S on the specific position of microscope carrier, can regulate so that the focus of ultra-short pulse laser bundle is focused in the position of hope, is the inside of substrate S by self motivating force, and can move freely to X, Y, Z direction along the cutting path of hope speed with hope.
In addition, can also have driver module 300, itself and focal adjustments module 200 links, and is used to transmit the motivating force of regulation, so that focal adjustments module 200 can move along the cutting path of the hope speed with hope.
Such driver module 300 preferably by for example electric motor and Poewr transmission mechanism (for example, gear, travelling belt, axle, cam etc.) constitute, but be not limited thereto, for example, can also come specific implementation by the various drive unit that comprises hydraulic type or air-compression type.
In addition, can also have and assemble module 400, it is configured between laser generation module 100 and the substrate S, is used for the ultra-short pulse laser beam convergence that will be produced by laser generation module 100 focal position in hope.
Such convergence module 400 preferably also comprises numerical aperture (Numerical Aperture, at least one lens NA) with about about 0.3~0.7 (being preferably about about 0.55).
On the other hand, can not possess the driver module 300 that is used for moving focal point adjustment module 200, and utilize at least one speculum or interferometer (not shown) etc., action that specific implementation is produced by laser generation module 100 under the state of having fixed focal adjustments module 200 ultra-short pulse laser bundle moves along the cutting path of hope.
Also can have monitoring module 500 in addition, it regulates multiplying power, focus with the ultra-short pulse laser bundle that produces with laser generation module 100 is consistent, before cutting processing, the user can directly specify the focal position of the ultra-short pulse laser bundle of wishing while observing picture, when cutting action, can confirm the operation process by picture in real time.
Such monitoring module 500 preferably comprises at least one CCD (Charge Coupled Device) photographic camera, watch-dog etc.
In addition, can also have auxiliary cutting module 600, it comes cutting substrate S efficiently for the ultra-short pulse laser bundle that utilizes low relatively output, and the ultra-short pulse laser bundle of the low relatively output that irradiation is produced by laser generation module 100 on the cutting path of the substrate S on the microscope carrier that is fixed to focal adjustments module 200, after forming line, apply homogeneous mechanical pressure along the line of above-mentioned formation.
The responsibility of auxiliary cutting module 600 like this is after as one man moving with the line of substrate S, to push with uniform power.Different with existing mode, no matter be to give mechanical force from bottom to top or give mechanical force from the top down to obtain neat cut surface.
In addition, can also have control module 700, it is used for integrally controlling the action of the input and output that comprise the ultra-short pulse laser bundle that laser generation module 100 produces and focus, focal adjustments module 200 and speed, the processing etc. of monitoring information in real time at other interior supplementary units.
Such control module 700 is preferably utilized home computer (Personal Computer, PC) come specific implementation, this home computer can make various control steering routineizations, and simple numerical value input of comprehensive adjustment and programming, but be not limited thereto, for example, can also utilize notebook (Notebook computer), PDA (Personal Digital Assistants), portable wireless terminal machine to wait specific implementation.
Below, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 1st embodiment is carried out specific description.
Fig. 3 is the synoptic diagram that is used to illustrate the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 1st embodiment.
With reference to Fig. 2 and Fig. 3, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 1st embodiment is following mode, promptly, make the focus inside of the substrate S on the microscope carrier that is fixed to focal adjustments module 200 and shine of the ultra-short pulse laser bundle that produces by laser generation module 100 along the cutting path of hope, direct internal becomes silk (filamentation) phenomenon etc. thus, forms the slot of certain depth in the inside of substrate S.
More particularly, the ultra-short pulse laser bundle that is produced by laser generation module 100 is focused shine, and produce the one-tenth silk phenomenon of substrate S inside in the inside of substrate S.
Promptly, when the ultra-short pulse laser bundle that is produced by laser generation module 100 passes through substrate S, its part is absorbed, and to structural molecule transmission energy, because the characteristic of the ultra-short pulse laser pulse that energy density is high, the energy density that absorbs is also high, so form plasma body in inside moment of substrate S.
When successive pulse enters, such plasma body sometimes to after the light characteristic of the pulse that enters bring influence.The plasma body of Sheng Chenging disappeared after certain life-span like this, thereby, be deformed into the structure different, perhaps utilize the cutting processing condition to be formed on the narrow and long space of width on the thickness direction, be referred to as " becoming silk " at the illuminated portion of ultra-short pulse laser bundle with peripheral material.
Should " become silk " can distinguish mutually with the gap or the crackle that are produced by thermal expansion, only the thermal expansion that forms because of the thermal energy of laser is the structural transformation of keeping under the state of the combination of molecule or connecting structure, the gap of Xing Chenging can not form carefully on thickness direction and be long thus, it is irregular that it forms form, and some statistical characteies also appear in the growth direction in gap.
Relative therewith, when using the ultra-short pulse laser bundle of energy density height and pulse width weak point, pulse width is shorter than the reaction times of molecule integrated structure, so bring influence to compare for peripheral molecule with heat or vibrational energy, can concentrate energy at the illuminated portion of ultra-short pulse laser bundle, and moment ground formation plasma body.
Thereby, can bring influence to peripheral part hardly, just can dissolve to moment the part of hope, form depleted region, so can on the direct of travel of ultra-short pulse laser bundle, form thin and long " becoming silk ", can reduce unwanted crackle like this, can improve the precision of cut surface.
On the other hand, when plural substrate forms multilayered structure,, just can obtain high-precision cutting result as long as focus in the inside of each layer and to the aforesaid mode of each layer application.
(the 2nd embodiment)
The cutter for substrate that utilizes the ultra-short pulse laser bundle of the present invention the 2nd embodiment, same with aforesaid the present invention the 1st embodiment, laser generation module 100, focal adjustments module 200 and supplementary unit have all similarly been used, this supplementary unit for example has driver module 300, convergence module 400, monitoring module 500, auxiliary cutting module 600 and control module 700 etc., about specifying with reference to the 1st embodiment of the present invention of these.
Especially, the focal adjustments module 200 that is applicable to the present invention the 2nd embodiment has following function, promptly, regulating so that focus after the inside of substrate S or the while along the cutting path of hope by the ultra-short pulse laser bundle of laser generation module 100 generations, regulate so that the focus of the ultra-short pulse laser bundle that is produced by laser generation module 100 is focused on identical cutting path in the upper surface of substrate S, form the slot V of certain depth once more at the upper surface of substrate S, perhaps regulate once more to focus in the inside of substrate S, form slot doubly.
Below, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 2nd embodiment is carried out specific description.
Fig. 4 is the synoptic diagram that is used to illustrate the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 2nd embodiment.
With reference to Fig. 2 and Fig. 4, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 2nd embodiment is following mode, promptly, make the focus inside of the substrate S on the microscope carrier that is fixed on focal adjustments module 200 and shine with after forming slot or the while of the ultra-short pulse laser bundle that produces by laser generation module 100 along the cutting path of hope, make the ultra-short pulse laser bundle that produces by laser generation module 100 on same cutting path, focus in the upper surface of substrate S and shine, on the upper surface of substrate S, form the slot V of certain depth thus once more.
In addition, can also make focus substrate S on the microscope carrier that is fixed on focal adjustments module 200 of the ultra-short pulse laser bundle that produces by laser generation module 100 inner and shine repeatedly more than at least twice, as dual, triple, form slot multiplely in the inside of substrate S along the cutting path of hope.
More particularly, same with aforesaid the present invention the 1st embodiment, at first will focus in the inside of substrate S and shine by the ultra-short pulse laser bundle that laser generation module 100 produces, generate into silk in the inside of substrate S.
After or simultaneously, will focus in the upper face of substrate S by the ultra-short pulse laser bundle that laser generation module 100 produces, on same cutting path, shine the ultra-short pulse laser bundle once more, append the slot V that forms certain depth at the upper surface of substrate.
The slot V that appends formation like this can further improve precision when cutting substrate S, and effectively is reduced in crackle or disrepair phenomenon on undesirable direction.
As mentioned above, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 2nd embodiment has the feature that at first guides phenomenon etc. in the inside of substrate S.The slot V that is appended on it only plays the effect of preliminary guiding cutting position when cutting, so do not need to form dark or big slot V.
Thereby,, and can effectively be reduced in the surface damage that is produced when utilizing the strong ultra-short pulse laser Shu Jinhang of intensity to shine on the substrate surface even utilize the ultra-short pulse laser bundle of weak strength also can obtain cutting effect.
On the other hand, under the situation of the display equipment that constitutes by plural multilayered structure, between sheet glass, be full of liquid crystal or other materials, so under the situation of the cutting mode of each sheet glass being used the present invention the 2nd embodiment respectively, can obtain the very high cutting result of precision.
(the 3rd embodiment)
The cutter for substrate that utilizes the ultra-short pulse laser bundle of the present invention the 3rd embodiment and aforesaid the 1st embodiment of the present invention are same, laser generation module 100, focal adjustments module 200 and supplementary unit have all similarly been used, this supplementary unit for example has driver module 300, convergence module 400, monitoring module 500, auxiliary cutting module 600 and control module 700 etc., about specifying with reference to the 1st embodiment of the present invention of these.
On the other hand, the focal adjustments module 200 that is applicable to the present invention the 3rd embodiment is different with the 1st and the 2nd embodiment of the invention described above, it has following function, be fixing base S, and regulate so that the ultra-short pulse laser bundle that produces by laser generation module 100 focus in the lower surface of substrate S gas cloud separated by a certain interval.
In addition, the focal adjustments module 200 that is applicable to the present invention the 3rd embodiment also can be as the focal adjustments module 200 that is applicable to the present invention the 1st embodiment, regulate so that the ultra-short pulse laser bundle that is produced by laser generation module 100 is focused in the inside of substrate S, form slot once more in the inside of substrate S.
Below, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 3rd embodiment is carried out specific description.
Fig. 5 is the synoptic diagram that is used to illustrate the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 3rd embodiment.
With reference to Fig. 2 and Fig. 5, the substrate cut mode of utilizing the ultra-short pulse laser bundle of the present invention the 3rd embodiment is following mode, promptly, make the ultra-short pulse laser bundle that produces by laser generation module 100 focus in the gas cloud of the lower surface of substrate S (being preferably in several cm) separated by a certain interval, and along the irradiation of the cutting path of hope, the light that reflects by boundary surface thus at the lower surface of substrate S and gas cloud, form the 1st slot V1 of certain depth at the upper surface (or upper surface position) of substrate S, by the air molecule that produces at the focus place of above-mentioned ultra-short pulse laser bundle light, at the 2nd slot V2 lower surface and the collinear position formation of the 1st slot V1 certain depth of substrate S with the boundary reflection of plasmasphere.
More particularly, the laser generation module 100 ultrashort wave pulse laser beam that vibrates and (be preferably about about 50FS~3PS) from femtosecond FS to psec PS.Vibrate if make very short pulse like this, then peak energy is very big, when irradiated substrate S, can produce various non-linear phenomenas like this.
In addition, when appending the lens of the value very big, about by about 0.3~0.7 (being preferably about about 0.55) of using numerical aperture NA, the ultra-short pulse laser bundle is concentrated on the area that focal length is very short and area is very little.Molecule in the substrate S is owing to powerful ultra-short pulse laser bundle is subjected to very strong electric field effects like this, and therefore, specific refractory power changes.
Thus, above-mentioned ultra-short pulse laser bundle is concentrated in substrate S more to high-density, is referred to as self-focusing effect (self-focusing).By such self-focusing effect, can on the depth direction of substrate S, form the very narrow and long line of width.
But, because the energy of above-mentioned ultra-short pulse laser bundle is strong, so the heat effect of its initiation may cause producing undesirable crackle or damage, therefore as mentioned above, actual focusing with the ultra-short pulse laser bundle is in the substrate S outside in the outside of the lower surface of substrate S.
On the other hand, the focusing with above-mentioned ultra-short pulse laser bundle does not have various reasons at the upside of substrate S upper surface, primary is because the focal length of the lens that use is very short, so when focusing when the upside of the upper surface of substrate S carries out cutting processing, the fragment (debris) that produces when worrying owing to cutting processing sustains damage lens.
In addition, also can't get rid of following worry, promptly above-mentioned ultra-short pulse laser intrafascicular from the light of the surface reflection of substrate S via the lens adverse current, laser system itself is caused damage.Still because same reason is concentrated very strong energy on minimum point, be decomposed and form plasma body so be positioned at air molecule on the focus, this also can bring damage to lens.
In contrast, when making above-mentioned ultra-short pulse laser bundle focus the outside in the lower surface of substrate S, can prevent damage to said lens or laser system, in addition, the fragment that produces when cutting processing drops down onto the downside of substrate S lower surface naturally owing to gravity, do not have residually on the surface of substrate S, can under the state of further optimizing, carry out cutting processing like this.
On the other hand, the laser of current use mainly has the pulse width of nanosecond degree, so its light does not have the sufficient peak energy that can cause non-linear phenomena, therefore add man-hour in the mode of utilizing the present invention to propose, inside at substrate S can not become enough line, and is easy to generate thermal damage or optical damage.But, under the situation of femtosecond pulse, produce aforesaid damage hardly.
Concrete situation of observing the cutting processing generation, the ultra-short pulse laser bundle that is produced by laser generation module 100 causes reflection on the boundary surface of mutually different medium, but brings the reflection of influence can be divided into two kinds to cutting processing.
The firstth, the light that on the boundary surface of the lower surface of substrate S and gas cloud, reflects, another is the light of the boundary reflection of the air molecule that produces at the focus place of strong ultra-short pulse laser bundle and plasmasphere.
Under the former situation, the reflection light concentrate on substrate S inside apart from the very near below part of upper surface, and go up to form from the line of the upper surface of substrate S to depth direction at depth direction (z direction of principal axis), concentrate on the lower surface inside of substrate S at the light of above-mentioned plasmasphere reflection, still the lower surface depth direction to the inside from substrate S forms line.
Therefore, on same cut surface, form two line that begin from the boundary surface at two ends by shining a ultra-short pulse laser bundle to depth direction.Come the microscope carrier of moving focal point adjustment module 200 with suitable speed, go up at length direction (x direction of principal axis) thus and evenly form two such line continuously, so on the upper surface of substrate S and lower surface, on same extended line, form one abreast respectively to the line of length direction what formed groove on the depth direction fully.
At this moment, the width of above-mentioned line, the degree of depth etc. show the functional form of the translational speed of the material of characteristic, substrate of rate repeatedly, the lens of the energy that depends on the ultra-short pulse laser bundle, ultra-short pulse laser bundle and microscope carrier, for example, use under the situation of substrate at liquid crystal indicator (LCD), because be the form that between two substrates, has liquid crystal, so can all form line via being radiated on two substrates of a ultra-short pulse laser bundle by the cutting mode of the present invention the 3rd embodiment, therefore can use highly beneficially.
In addition, femtosecond FS pulse laser is because concentrate in extremely short moment and to emit very strong energy, so have low output and also can carry out the such advantage of cutting processing fast even compare with other laser equipments.
In above-mentioned cutting mode after the irradiation of the ultra-short pulse laser bundle that is through with, utilize additional auxiliary cutting module 600, the both sides of the line that generates on along its length apply uniform pressure, and can finish neat cutting this moment along the line of the depth direction that has generated.
As mentioned above, the present invention relates to be used for high precision and the promptly device and the method for cutting substrate, especially, can cut the multiple glazing substrate that glass substrate for display etc. is made of multilayered structure accurately.
That is, the present invention proposes a cutting mode in the mode of utilizing ultrashort wave (pulse femtosecond~psec) laser, that foundation becomes silk to carry out in substrate inside by the plasma body of ultra-short pulse laser Shu Shengcheng; The inner plasma body Cheng Sihou that generates shines the ultra-short pulse laser bundle once more to the surface of substrate and appends the mode that formation cutting guiding groove cuts at substrate; And the non-linear effect that makes full use of femtosecond FS laser, by a ultra-short pulse laser bundle be radiated at substrate form the remote back focus mode that two imperceptible lines of cut cut simultaneously apart from the very near below of upper and lower surface.
The 1st mode is the mode that can utilize the ultra-short pulse laser bundle of the pulse width about having from femtosecond FS to psec PS generally to use, it utilizes more to the substrate internal delivery at short notice energy of the high ultra-short pulse laser pulse of energy density, thus at the inner plasma body that generates of substrate, and form to the thin of thickness direction and long depleted region, silk, can obtain neat cut surface like this.
The 2nd mode is appended at the 1st mode the upper surface of substrate is focused, and boost ultra-short pulse laser bundle, form slot once more at upper surface of base plate, determined the inceptive direction of cutting thus by the slot on the extended line that is located at the inner one-tenth silk that forms of substrate, help the formation of cut surface, can obtain more high-precision cutting result like this.
The 3rd mode is only to utilize the mode of femtosecond FS laser, when the upper surface from substrate shines the ultra-short pulse laser bundle, focus in than the lower surface of substrate more downside the position and emit light, form imperceptible line of cut thus respectively by only shining ultra-short pulse laser bundle and at the two ends, inside of substrate, can prevent the unwanted glass crack that too strong ultra-short pulse laser energy is caused like this, and the fragment that is produced when utilizing gravity to remove cutting processing naturally, can minimize by thus obtained mismachining tolerance, and as the self-focusing of the distinctive non-linear phenomena of femtosecond FS pulse, therefore sharp-pointed at the substrate internal production and grow line of cut can carry out the ultraprecise cutting.
Because the cutting mode that the invention described above proposed is very simple,, also need not to use deleterious chemical substance so need not too much activity time.In tens of microns, is uniform by the line of cut thickness of above-mentioned ultra-short pulse laser Shu Shengcheng when in several microns.
In addition, above-mentioned ultra-short pulse laser bundle can only transmit energy to the part of hope, so cutting be included in the such display base plate of the liquid crystal indicator LCD that seizes liquid crystal between two sheet glass on both sides by the arms interior, when having general two substrates with the rhythmo structure of upper glass plates, applicable too mode proposed by the invention, it can demonstrate the cutting characteristic more superior than other existing mode.
More than, the aforementioned cutter for substrate of ultra-short pulse laser bundle and the preferred embodiment of cutting method thereof of utilizing of the present invention is illustrated, but the invention is not restricted to this, can carry out various distortion back and implement in the scope of claim scope and detailed description of the invention and accompanying drawing, these also belong to the present invention.