CN112621392A - Processing method of large-size ultrathin high-precision lithium niobate wafer - Google Patents
Processing method of large-size ultrathin high-precision lithium niobate wafer Download PDFInfo
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- GQYHUHYESMUTHG-UHFFFAOYSA-N lithium niobate Chemical compound [Li+].[O-][Nb](=O)=O GQYHUHYESMUTHG-UHFFFAOYSA-N 0.000 title claims abstract description 58
- 238000003672 processing method Methods 0.000 title claims abstract description 22
- 238000000227 grinding Methods 0.000 claims abstract description 101
- 238000005498 polishing Methods 0.000 claims abstract description 78
- 238000012545 processing Methods 0.000 claims abstract description 12
- 230000005484 gravity Effects 0.000 claims abstract description 8
- 239000004570 mortar (masonry) Substances 0.000 claims description 35
- 230000000694 effects Effects 0.000 claims description 30
- 239000013078 crystal Substances 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 13
- 239000002270 dispersing agent Substances 0.000 claims description 12
- 239000004576 sand Substances 0.000 claims description 12
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 12
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 12
- 238000005520 cutting process Methods 0.000 claims description 10
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 238000013461 design Methods 0.000 claims description 3
- 239000004065 semiconductor Substances 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 239000000463 material Substances 0.000 abstract description 6
- 238000004880 explosion Methods 0.000 abstract description 2
- 239000012634 fragment Substances 0.000 abstract description 2
- 235000012431 wafers Nutrition 0.000 description 75
- 230000000052 comparative effect Effects 0.000 description 12
- 238000003825 pressing Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 6
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical compound CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 description 5
- 238000005336 cracking Methods 0.000 description 5
- 238000007907 direct compression Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 230000003287 optical effect Effects 0.000 description 5
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- 229910003460 diamond Inorganic materials 0.000 description 4
- 239000010432 diamond Substances 0.000 description 4
- 239000002075 main ingredient Substances 0.000 description 4
- ZXVOCOLRQJZVBW-UHFFFAOYSA-N azane;ethanol Chemical compound N.CCO ZXVOCOLRQJZVBW-UHFFFAOYSA-N 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000002950 deficient Effects 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000007517 polishing process Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000012797 qualification Methods 0.000 description 2
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- 238000001179 sorption measurement Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
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- 238000005260 corrosion Methods 0.000 description 1
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- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 239000000382 optic material Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000005622 photoelectricity Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
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- 238000002360 preparation method Methods 0.000 description 1
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- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
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- 238000010361 transduction Methods 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B41/00—Component parts such as frames, beds, carriages, headstocks
- B24B41/06—Work supports, e.g. adjustable steadies
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Abstract
The invention relates to the technical field of semiconductor material processing, in particular to a processing method of a large-size ultrathin high-precision lithium niobate wafer, which comprises the steps of slicing, chamfering, grinding 800, blackening, grinding 2000 and polishing; the step 800 of grinding and the step 2000 of grinding both adopt a double-sided grinder, and the grinding and pressurizing mode adopts a sectional slow pressurizing mode at the temperature of 22 +/-2 ℃; the polishing step adopts a double-sided polishing machine, the maximum rotation speed of the equipment is 6-10rpm at the temperature of 22 +/-2 ℃, and SiO is adopted2The specific gravity of the polishing solution is 1.06-1.20, and the polishing pressurization mode adopts a sectional slow pressurization mode. The mode of slow and gradual pressurization is adopted during pressurization, so that the conditions of scratches, fragments, splinters and the like are greatly reduced, and the fixture provided by the invention can effectively reduce the conditions of edge collapse, edge explosion, insufficient grinding and the like, greatly improve the yield of production, and get rid of the traction of the application of semiconductor machine equipment of manufacturers.
Description
Technical Field
The invention relates to the technical field of semiconductor material processing, in particular to a processing method of a lithium niobate crystal substrate.
Background
Lithium niobate (LiNbO)3) Is a compound of niobium, lithium and oxygen, is a negative crystal (n 0)>ne). The lithium niobate has a relative density of 4.30, a lattice constant a of 0.5147 μm, c of 1.3856 μm, a melting point of 1240 ℃, a mohs hardness of 5, a refractive index n0 of 2.297, ne of 2.208(λ of 600 μm), a dielectric constant ∈ of 44, ∈ of 29.5, ∈ of 84, and ∈ of 30. Lithium niobate is a ferroelectric crystal having a Curie point of 1140 ℃, a spontaneous polarization of 50X 10C/cm' and a thermal conductivity of 0.056 (W/cm. K). The lithium niobate crystal after distortion treatment has multiple performances of piezoelectricity, ferroelectricity, photoelectricity, nonlinear optics, thermoelectricity and the like, and simultaneously has a photorefractive effect. Their single crystals are important materials for optical waveguides, mobile phones, piezoelectric sensors, optical modulators and various other linear and nonlinear optical applications. Lithium niobate crystal is one of the most widely used novel inorganic materials at present, and is a good piezoelectric transduction material, a ferroelectric material and an electro-optic material. The lithium niobate is used as an electro-optical material to play an optical modulation role in optical communication.
The performance of the electronic element has extremely high requirements on the lattice integrity of the surface of the lithium niobate wafer, and the lithium niobate wafer has extremely high flatness, no damage and ultra-smooth surface and no crystal orientation deviation. Meanwhile, the common wafer has a phenomenon of surface static electricity accumulation. The problem can be solved by a blackening process, and meanwhile, the lens has a low pyroelectric effect and better meets the law and desire of the development of the semiconductor industry.
At present, with the rapid development of the semiconductor industry, the demand of lithium niobate wafers is gradually increased, and in order to improve the yield and reduce the cost, the wafers need to be developed towards a large size, but the processing of the large-size lithium niobate wafers lacks a general process platform like silicon, and the wafers need to be developed towards 8 inches to get rid of the traction of the application of semiconductor machine equipment of manufacturers. The 8-inch lithium niobate wafer is larger than a conventional wafer in size, and larger processing stress is generated in the processing process, so that defects such as edge cracking, chipping and splintering are caused. And the larger the size, the more difficult the indexes of wafers such as TTV, WARP, BOW, PLTV and the like reach the equivalent level of the conventional size in the processing process.
Chinese patent application CN111230598A discloses a preparation method of an 8-inch lithium niobate wafer, which adopts a triple etching method to solve the problems of serious internal stress deformation of the lithium niobate wafer and easy fragmentation in the production process of the wafer; the polishing process adopts a porous ceramic disc for adsorption, so that the problem that TTV is difficult to control caused by the traditional wax pasting process is solved; however, in actual operation, the acid solution used for corrosion has potential safety hazards to the environment and human body, and the porous ceramic disc is adopted for adsorption, so that the precision requirement on equipment and accessories is extremely high, and only single-side polishing can be realized.
The applicant discloses in CN107665813A a method for processing a lithium tantalate crystal substrate, which includes steps of slicing, chamfering, blackening, grinding, rough polishing and fine polishing, wherein a diamond polishing solution is adopted in the rough polishing and the fine polishing, the diamond polishing solution is composed of diamond micro powder, ethylene glycol, glycerol, ethanol ammonia and deionized water, and has a PH value of 9-11, wherein the content of the diamond micro powder is 20-25%, the content of the ethylene glycol is 8-15%, the content of the glycerol is 3-5%, the content of the ethanol ammonia is 0.1-0.3%, and the content of the deionized water is 60-65%. The invention can greatly improve the surface smoothness of the lithium tantalate wafer, reduce the surface roughness of the lithium tantalate wafer, eliminate stress and achieve the mirror polishing effect, thereby reducing the production cost and improving the qualification rate of products. However, lithium tantalate and lithium niobate have very different physical properties, and the processing method of lithium tantalate is not suitable for lithium niobate.
Disclosure of Invention
The invention aims to provide a processing method of a large-size ultrathin high-precision lithium niobate wafer, which can be used for producing 8-inch lithium niobate wafers in batches, realizing double-sided processing, greatly improving the production efficiency, being safe and reliable, ensuring the performance and the quality of the wafer, and achieving the purposes of saving the production cost, improving the product qualification rate, reducing the stress problem of the large-size wafer and getting rid of the application traction of semiconductor machine equipment of manufacturers.
In order to achieve the purpose, the invention provides the following technical scheme:
a processing method of a large-size ultrathin high-precision lithium niobate wafer comprises the steps of slicing, chamfering, grinding 800, blackening, grinding 2000 and polishing;
the step 800 of grinding and the step 2000 of grinding both adopt a double-sided grinder, and the grinding and pressurizing mode adopts a sectional slow pressurizing mode at the temperature of 22 +/-2 ℃;
wherein, the sectional slow pressurizing mode of the grinding 800 is as follows: the first stage is 1min without pressurization; second stage pressurizing for 3min at a rate of 2g/cm per minute2(ii) a Pressurizing for 2min at a rate of 3g/cm per minute2And pressurizing for 2min at a rate of 4g/cm per minute in the fourth stage2Co-pressurizing to 20g/cm2;
The stepwise slow pressurization mode of the grinding 2000 is: the first stage is 1min without pressurization; the second stage is pressurized for 3min at a rate of 4g/cm per minute2(ii) a Pressurizing for 2min at a rate of 6g/cm per minute2(ii) a Pressurizing for 2min at a rate of 8g/cm per minute in the fourth stage2Co-pressurizing to 40g/cm2(ii) a The flow rate of the mortar is 5-15L/cm2The maximum rotation speed of the equipment is 6-10 rpm;
the polishing step adopts a double-sided polishing machine, the maximum rotation speed of the equipment is 6-10rpm at 22 +/-2 ℃, the polishing solution adopts FUJIMI Compol403 polishing solution, and the main component is SiO2The specific gravity is 1.06-1.20, the polishing and pressurizing mode adopts a sectional slow pressurizing mode, and the pressurizing mode is as follows: the first stage is 1min without pressurization; the second stage is pressurized for 4min at a rate of 10g/cm per minute2(ii) a Pressurizing for 4min at a rate of 15g/cm per minute2(ii) a Pressurizing for 5min at a rate of 20g/cm per minute in the fourth stage2Co-pressurizing to 200g/cm2(ii) a The flow rate of the polishing solution is 10-12L/cm2。
The sectional slow pressurizing mode is that before the grinding disc is pressed, the lower disc is started to make the mortar distributed uniformly, and the wafer and the clamp are checked to be fixed, and after the wafer and the clamp are operated for a period of time, the pressurizing is carried out, and the mode of slow and gradual pressurizing is adopted during pressurizing.
Fig. 2-4 are graphs showing the relationship between the pressure and time in the grinding process 800, the grinding process 2000 and the polishing process in the direct pressing mode and the step pressing mode, respectively, and it can be seen that:
direct pressure mode of milling 800 at 4g/cm per minute2Pressurizing at a pressurizing rate of 5min to 20g/cm2(ii) a Direct pressure mode of grinding 2000 at 8g/cm per minute2Pressurizing at a pressurizing rate of 5min to 40g/cm2(ii) a Direct pressure mode of polishing step at 20 g/cm/min2Pressurizing at a pressurizing rate of 10min to 200g/cm2。
Compared with the prior art, the direct pressurizing mode is too rigid and mechanical, the problems of scratching, splintering and the like are easily caused, the problems are not easy to find and remedy, the time is reserved for observation and adjustment by sectional pressurizing, the pressurizing speed is slow and mild, the processing quality can be effectively guaranteed, and the possibility of scratching and splintering is reduced.
Wherein, the mortar ground in the grinding 800 step consists of silicon carbide sand GC800 #: water: mortar dispersant 13.5KG:30L: 1.7L; the mortar ground in the grinding 2000 step consists of silicon carbide sand GC2000 #: water: mortar dispersant 13.5KG:30L: 1.7L.
Wherein the polishing solution comprises SiO as the main component2The specific gravity is 1.06-1.20.
Wherein, the grinding effect in the grinding 800 step reaches TTV less than or equal to 5 μm, Bow less than or equal to 30 μm, and the grinding effect in the grinding 2000 step reaches TTV less than or equal to 4 μm, and Bow less than or equal to 25 μm.
Wherein the polishing effect of the polishing step requires that the TTV of the wafer is less than or equal to 3 μm, the Bow is less than or equal to 20 μm, the WARP is less than 40 μm, the PLTV is more than 95 percent, and the wafer has mirror effect and no stress.
Wherein the lithium niobate wafer is an 8-inch lithium niobate wafer.
The fixture adopted in the steps of grinding 800, grinding 2000 and polishing is a planetary wheel, and the wafer placement position in the planetary wheel adopts an eccentric design;
the wafer placing position is circular, and a rubber ring with the diameter of 200.2mm and the width of 5mm is arranged at the edge of the wafer placing position;
five circular drainage holes are distributed around the wafer placement position, the diameters of the five circular drainage holes are respectively one 60mm, two 40mm and two 20mm, the circle center of the wandering star wheel is used as the circle center, a circle with the diameter of 290mm is made, the wafer placement circle and the drainage holes are all inscribed with the circle, the circle center of the wafer placement circle and the circle center of the 60mm drainage hole are on the same diameter line and are positioned on two sides, the circle center of the 40mm drainage hole is positioned on the circle center of the wandering star wheel, the radius of the drainage empty circle center passing 60mm is used as a reference edge, the circle center of the drainage hole is respectively deflected leftwards and rightwards by 60 degrees, the circle center of the 20mm drainage hole is positioned on the circle center of the wandering star wheel, the radius of the. The said wandering star wheel is shown in figure 1.
Wherein the slicing step is specifically that the lithium niobate crystal bar is cut into a wafer with the thickness of 250-300 mu m by utilizing a linear cutting device at the linear velocity of a steel wire of 400-1000m/min and the temperature of 22 +/-2 ℃, and the TTV of the wafer is less than or equal to 10 mu m;
the chamfering step is specifically that a T-shaped grinding wheel is used for chamfering, and the right angle of the lithium niobate wafer is chamfered into a fillet of about R0.1 at the rotation speed of the grinding wheel of 600 plus one year at the temperature of 22 +/-2 ℃, so that the probability of edge cracking, chipping and splintering can be effectively reduced.
The blackening step is to put the wafer into a blackening furnace for blackening, the temperature is 300-380 ℃, the flow rate of the protective gas is 3-11L, and the reduction time is 4-24 hours, so that the probability of warping and cracking can be effectively reduced.
A lithium niobate wafer prepared by the processing method of the large-size ultrathin high-precision lithium niobate wafer.
Compared with the prior art, the invention has the beneficial effects that:
the processing method and the clamp for the large-size ultrathin high-precision lithium niobate wafer have excellent treatment effect on the 8-inch lithium niobate wafer, and greatly improve the production efficiency. The novel segmented pressurization mode is adopted for grinding and polishing, the slow and gradual pressurization mode is adopted during pressurization, the conditions of scratches, fragments, splinters and the like are greatly reduced, and the fixture provided by the invention is matched, so that the conditions of edge collapse, edge explosion, insufficient grinding and the like can be effectively reduced, the yield of production is greatly improved, and the traction of semiconductor machine equipment of a manufacturer is avoided.
Drawings
FIG. 1 is a schematic view of a fixture used in the present invention;
FIG. 2 is a graph comparing the pressurization pattern of the direct pressurization and the staged pressurization during the grinding 800 step;
FIG. 3 is a graph comparing the pressurization pattern of the direct pressurization and the staged pressurization in the grinding 2000 step;
FIG. 4 is a graph comparing the pressing manner of the direct pressing and the stepwise pressing in the polishing step;
FIG. 5 shows the test results of the fixture and the segmented pressurization method of the present invention;
FIG. 6 shows the test results of the conventional planetary wheel and segmented pressurization method;
FIG. 7 shows the test results of the fixture and direct compression method of the present invention;
fig. 8 shows the test results of the conventional planetary wheel and direct pressing method.
Detailed Description
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.
Example 1A jig (planetary wheel) and segmented pressing according to the invention were used
As shown in fig. 1, the fixture adopted in the present embodiment is a planetary wheel 1, and the wafer placement position 2 in the planetary wheel 1 adopts an eccentric design; the whole wafer can be processed to the maximum extent, and the processing precision is ensured.
The wafer placing position 2 is circular, and a rubber ring 4 with the diameter of 105mm and the thickness of 5mm is arranged at the edge of the wafer placing position 2; the wafer can be effectively protected, the phenomena of edge cracking, edge collapse, cracking, chipping, disc collapse and the like can be greatly reduced, and the yield and the stability are greatly improved.
Five circular drainage holes 3 are distributed around the wafer placing position 2, the diameters of the five circular drainage holes are respectively one 60mm, two 40mm and two 20mm, the circle center of the wandering star wheel is used as the circle center, a circle with the diameter of 290mm is made, the wafer placing circle and the drainage holes are all inscribed with the circle, the circle center of the wafer placing circle and the circle center of the 60mm drainage holes are on the same diameter line and are positioned on two sides, the circle center of the 40mm drainage hole is positioned on the circle center of the wandering star wheel, the radius of the drainage empty circle center passing 60mm is used as a reference edge, the circle center of the drainage hole is respectively deflected to the left and the right by 60 degrees, the circle center of the 20mm drainage hole is positioned on the circle center of the wandering star wheel, the radius.
A processing method of a large-size ultrathin high-precision lithium niobate wafer comprises the following steps:
1) slicing: under the conditions that the linear velocity of a steel wire is 600m/min and the temperature is 22 ℃, cutting a lithium niobate crystal bar into wafers with the thickness of 290 mu m by using linear cutting equipment, wherein the TTV of the wafers is less than or equal to 10 mu m;
2) chamfering: chamfering is carried out by utilizing a T-shaped grinding wheel, and under the conditions that the rotating speed of the grinding wheel is 800rpm/min and the temperature is 22 ℃, the right angle of the lithium niobate wafer is chamfered into a fillet of about R0.1;
3) grinding 800: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC800 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is a first section 1min, the pressurizing mode is not pressurized, and the pressurizing rate of a second section of pressurizing for 3min is 2g/cm per minute2And pressurizing for 2min in the third stage at a rate of 3g/cm per minute2And pressurizing for 2min at a rate of 4g/cm per minute in the fourth stage2Co-pressurizing to 20g/cm2The flow rate of the mortar is 10L/cm2The maximum rotation speed of the equipment is 8 rpm; the grinding fixture adopts a planetary wheel, the grinding effect reaches TTV less than or equal to 5 μm, and Bow less than or equal to 30 μm;
4) blackening: putting the wafer into a blackening furnace for blackening treatment, wherein the temperature is 340 ℃, the flow of protective gas is 7L, and the reduction time is 16 hours;
5) grinding 2000: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC2000 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is that the first section is pressurized for 3min, and the pressurizing rate is 4g/cm per minute2Second stage pressurizing for 2min at a rate of 6g/cm per minute2And pressurizing for 2min in the third stage at a rate of 8g/cm per minute2Co-pressurizing to 40g/cm2The flow rate of the mortar is 11L/cm2The maximum rotation speed of the device is 8rpm, the grinding fixture adopts a planetary wheel (the planetary wheel in the same grinding step 800), the grinding effect reaches TTV less than or equal to 4 μm, and Bow less than or equal to 25 μm;
6) polishing: polishing with a double-side polishing machine at 22 deg.C and maximum rotation speed of 9rpm, wherein the polishing solution is FUJIMI Compol403 polishing solution containing SiO as main ingredient2The specific gravity is 1.12, the polishing and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is that the first-stage pressurizing is carried out for 4min, and the pressurizing rate is 10g/cm per minute2And the second stage is pressurized for 4min at a rate of 15g/cm per minute2And pressurizing for 5min in the third stage at a rate of 20g/cm per minute2Co-pressurizing to 200g/cm2. The flow rate of the polishing solution was 11L/cm2The polishing fixture adopts a planetary wheel (the same as the planetary wheel in the grinding 800 step), the polishing effect is that the TTV of the wafer is less than or equal to 3 mu m, the Bow is less than or equal to 20 mu m, the WARP is less than 40 mu m, the PLTV is more than 95 percent, and the polishing fixture has mirror surface effect and no stress.
Comparative example 1 Using a conventional planetary wheel and segmented pressurization
A processing method of a large-size ultrathin high-precision lithium niobate wafer comprises the following steps:
1) slicing: under the conditions that the linear velocity of a steel wire is 600m/min and the temperature is 22 ℃, cutting a lithium niobate crystal bar into wafers with the thickness of 290 mu m by using linear cutting equipment, wherein the TTV of the wafers is less than or equal to 10 mu m;
2) chamfering: chamfering is carried out by utilizing a T-shaped grinding wheel, and under the conditions that the rotating speed of the grinding wheel is 800rpm/min and the temperature is 22 ℃, the right angle of the lithium niobate wafer is chamfered into a fillet of about R0.1;
3) grinding 800: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC800 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is a first section 1min, the pressurizing mode is not pressurized, and the pressurizing rate of a second section of pressurizing for 3min is 2g/cm per minute2And pressurizing for 2min in the third stage at a rate of 3g/cm per minute2And pressurizing for 2min at a rate of 4g/cm per minute in the fourth stage2Co-pressurizing to 20g/cm2The flow rate of the mortar is 10L/cm2The maximum rotation speed of the device is 8rpm, the grinding fixture adopts the traditional planetary wheel, the grinding effect reaches TTV less than or equal to 9 μm, and Bow less than or equal to 35 μm;
4) blackening: putting the wafer into a blackening furnace for blackening treatment, wherein the temperature is 340 ℃, the flow of protective gas is 7L, and the reduction time is 16 hours;
5) grinding 2000: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC2000 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is a first section of 1min, the pressurizing mode is not used, the second section of pressurizing mode is used for 3min, and the pressurizing speed is 4g/cm per minute2And pressurizing for 2min in the third stage at a rate of 6g/cm per minute2And pressurizing for 2min at a rate of 8g/cm per minute in the fourth stage2Co-pressurizing to 40g/cm2The flow rate of the mortar is 11L/cm2The maximum rotation speed of the device is 8rpm, the grinding fixture adopts the traditional planetary wheel, the grinding effect reaches TTV less than or equal to 8 μm, and Bow less than or equal to 30 μm;
6) polishing: polishing with a double-side polishing machine at 22 deg.C and maximum rotation speed of 9rpm, wherein the polishing solution is FUJIMI Compol403 polishing solution containing SiO as main ingredient2The specific gravity is 1.12, the polishing and pressurizing mode adopts a sectional slow pressurizing mode, the pressurizing mode is a first section of 1min without pressurizing, and a second section of pressurizing is 4min, the pressurizing rate is 10g/cm per minute2And pressurizing for 4min in the third stage at a rate of 15g/cm per minute2Fourth stage of pressurization5min, pressurizing rate of 20 g/cm/min2Co-pressurizing to 200g/cm2The flow rate of the polishing solution is 11L/cm2The polishing fixture adopts the traditional planetary wheel, the polishing effect is that the TTV of the wafer is less than or equal to 6 microns, the Bow is less than or equal to 20 microns, the WARP is less than 40 microns, the PLTV is more than 95 percent, the thickness is 250 +/-15 microns, and the polishing fixture has mirror surface effect and no stress.
In this case, the conventional wandering wheel lacks a rubber ring at the edge of the wafer placement position, as compared with the wandering wheel of embodiment 1.
Comparative example 2 use of a fixture (planetary wheel) according to the invention and direct compression
A processing method of a large-size ultrathin high-precision lithium niobate wafer comprises the following steps:
1) slicing: under the conditions that the linear velocity of a steel wire is 600m/min and the temperature is 22 ℃, cutting a lithium niobate crystal bar into wafers with the thickness of 290 mu m by using linear cutting equipment, wherein the TTV of the wafers is less than or equal to 10 mu m;
2) chamfering: chamfering is carried out by utilizing a T-shaped grinding wheel, and under the conditions that the rotating speed of the grinding wheel is 800rpm/min and the temperature is 22 ℃, the right angle of the lithium niobate wafer is chamfered into a fillet of about R0.1;
3) grinding 800: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC800 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a direct pressurizing mode, and the pressurizing mode adopts a pressurizing mode of 4g/cm per minute2Pressurizing at a pressurizing rate of 5min to 20g/cm2The flow rate of the mortar is 10L/cm2The maximum rotation speed of the equipment is 8rpm, the wandering star wheel in the embodiment 1 is adopted as the grinding clamp, the grinding effect reaches TTV less than or equal to 9 microns, and Bow less than or equal to 35 microns;
4) blackening: putting the wafer into a blackening furnace for blackening treatment, wherein the temperature is 340 ℃, the flow of protective gas is 7L, and the reduction time is 16 hours;
5) grinding 2000: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC2000 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a direct pressurizing mode, and the pressurizing mode adopts a pressurizing mode of 8g/cm per minute2Pressurizing at a pressurizing rate of 5min to 40g/cm2The flow rate of the mortar is 11L/cm2The maximum rotation speed of the equipment is 8rpm, the wandering star wheel in the embodiment 1 is adopted as the grinding clamp, the grinding effect reaches that TTV is less than or equal to 8 microns, and Bow is less than or equal to 30 microns;
6) polishing: polishing with a double-side polishing machine at 22 deg.C and maximum rotation speed of 9rpm, wherein the polishing solution is FUJIMI Compol403 polishing solution containing SiO as main ingredient2The specific gravity is 1.12, the polishing and pressurizing mode adopts a sectional slow pressurizing mode, and the pressurizing mode is a direct pressurizing mode and is 20g/cm per minute2Pressurizing at a pressurizing rate of 10min to 200g/cm2The flow rate of the polishing solution is 11L/cm2The polishing fixture adopts the planetary wheel of the embodiment 1, and has the polishing effects that the TTV of the wafer is less than or equal to 6 microns, the Bow is less than or equal to 20 microns, the WARP is less than 40 microns, the PLTV is more than 95 percent, the thickness is 250 +/-15 microns, and the polishing fixture has mirror surface effect and no stress.
Comparative example 3 Using a conventional planetary wheel and direct compression
A processing method of a large-size ultrathin high-precision lithium niobate wafer comprises the following steps:
1) slicing: under the conditions that the linear velocity of a steel wire is 600m/min and the temperature is 22 ℃, cutting a lithium niobate crystal bar into wafers with the thickness of 290 mu m by using linear cutting equipment, wherein the TTV of the wafers is less than or equal to 10 mu m;
2) chamfering: chamfering is carried out by utilizing a T-shaped grinding wheel, and under the conditions that the rotating speed of the grinding wheel is 800rpm/min and the temperature is 22 ℃, the right angle of the lithium niobate wafer is chamfered into a fillet of about R0.1;
3) grinding 800: grinding by a double-sided grinder, wherein the mortar comprises the following components at the temperature of 22 ℃: silicon carbide sand GC800 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a direct pressurizing mode, and the pressurizing mode adopts a pressurizing mode of 4g/cm per minute2Pressurizing at a pressurizing rate of 5min to 20g/cm2The flow rate of the mortar is 10L/cm2The maximum rotation speed of the device is 8rpm, the grinding fixture adopts the traditional planetary wheel, the grinding effect reaches TTV less than or equal to 15 μm, and Bow less than or equal to 40 μm;
4) blackening: putting the wafer into a blackening furnace for blackening treatment, wherein the temperature is 340 ℃, the flow of protective gas is 7L, and the reduction time is 16 hours;
5) grinding 2000: grinding by a double-sided grinderUnder the condition that the temperature is 22 ℃, the mortar comprises the following components: silicon carbide sand GC2000 #: water: the mortar dispersant is 13.5KG:30L:1.7L, the grinding and pressurizing mode adopts a direct pressurizing mode, and the pressurizing mode adopts a pressurizing mode of 8g/cm per minute2Pressurizing at a pressurizing rate of 5min to 40g/cm2The flow rate of the mortar is 11L/cm2The maximum rotation speed of the device is 8rpm, the grinding fixture adopts the traditional planetary wheel, the grinding effect reaches TTV less than or equal to 13 μm, and Bow less than or equal to 30 μm;
6) polishing: polishing with a double-side polishing machine at 22 deg.C and maximum rotation speed of 9rpm, wherein the polishing solution is FUJIMI Compol403 polishing solution containing SiO as main ingredient2The specific gravity is 1.12, the polishing and pressurizing mode adopts a sectional slow pressurizing mode, and the pressurizing mode is a direct pressurizing mode and is 20g/cm per minute2Pressurizing at a pressurizing rate of 10min to 200g/cm2The flow rate of the polishing solution is 11L/cm2The polishing fixture adopts the traditional planetary wheel, the polishing effect is that the TTV of the wafer is less than or equal to 10 mu m, the Bow is less than or equal to 20 mu m, the WARP is less than 40 mu m, the PLTV is more than 95 percent, the thickness is 250 +/-15 mu m, and the polishing fixture has mirror surface effect and no stress.
The 8-inch lithium niobate wafers obtained in example 1 and comparative examples 1 to 3 described above were subjected to various tests using a TROPEL flatness tester, and the test results are shown in fig. 4 to 8.
And the data for example 1 and comparative examples 1-3 are summarized as shown in table 1.
TABLE 1
Experimental group | TTV | Thickness of | WARP | BOW |
Example 1 planetary wheel + segmented pressurization of the invention | 1.247μm | 242.033μm | 8.612μm | 7.268μm |
Comparative example 1 traditional planetary wheel + segment pressurization | 5.015μm | 237.400μm | 16.424μm | 13.663μm |
Comparative example 2 planetary wheel + direct compression according to the invention | 5.524μm | 238.531μm | 14.745μm | 12.249μm |
Comparative example 3 traditional planetary wheel + direct compression | 9.665μm | 241.362μm | 19.242μm | 13.426μm |
The results show that the parameters are adjusted in a controllable range by using the planetary gear and the sectional slow pressurizing mode, the grinding and polishing effects can be ensured, the TTV is less than 3 mu m, and the BOW is less than or equal to 10 mu m. By using the planetary wheel and direct pressurizing mode and the traditional planetary wheel and segmented slow pressurizing mode, TTV is larger than 5 mu m, and BOW is larger than 10 mu m. And by using the traditional planetary wheel and direct pressing mode, the TTV reaches 9.665 mu m, which is far larger than 1.247 mu m with the best processing effect.
The number of test pieces and the ratio of defective pieces in example 1 and comparative examples 1 to 3 are shown in table 2.
TABLE 2
Experimental group | Number of test pieces | TTV exceeds standard | Insufficient grinding | Collapsed edge | Burst edge | Pieces of | Percent of pass |
Example 1: | 120 | 4 | 1 | 0 | 0 | 2 | 94.166% |
comparative example 1: | 120 | 8 | 2 | 2 | 3 | 4 | 84.166% |
comparative example 2: | 120 | 7 | 3 | 2 | 1 | 3 | 86.666% |
comparative example 3: | 120 | 10 | 5 | 5 | 3 | 6 | 75.833% |
from the above results, it can be seen that example 1 can effectively reduce the defective rate and improve the yield in terms of TTV, grinding sufficiency, edge sagging, and edge popping.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (10)
1. A processing method of a large-size ultrathin high-precision lithium niobate wafer is characterized by comprising the following steps: comprises the steps of slicing, chamfering, grinding 800, blackening, grinding 2000 and polishing;
the step 800 of grinding and the step 2000 of grinding both adopt a double-sided grinder, and the grinding and pressurizing mode adopts a sectional slow pressurizing mode at the temperature of 22 +/-2 ℃;
wherein, the pressurization mode of the grinding 800 is as follows: the first stage is 1min without pressurization; second stage pressurizing for 3min at a rate of 2g/cm per minute2(ii) a Pressurizing for 2min at a rate of 3g/cm per minute2And pressurizing for 2min at a rate of 4g/cm per minute in the fourth stage2Co-pressurizing to 20g/cm2;
The pressurization method of the polishing 2000 is: the first stage is 1min without pressurization; the second stage is pressurized for 3min at a rate of 4g/cm per minute2(ii) a Pressurizing for 2min at a rate of 6g/cm per minute2(ii) a Pressurizing for 2min at a rate of 8g/cm per minute in the fourth stage2Co-pressurizing to 40g/cm2(ii) a The flow rate of the mortar is 5-15L/cm2The maximum rotation speed of the equipment is 6-10 rpm;
the polishing step adopts a double-sided polishing machine, the maximum rotation speed of the equipment is 6-10rpm at the temperature of 22 +/-2 ℃, and SiO is adopted2The specific gravity of the polishing solution is 1.06-1.20, and the polishing pressurization mode adopts a sectional slow pressurization mode, and the pressurization mode is as follows: the first stage is 1min without pressurization; the second stage is pressurized for 4min at a rate of 10g/cm per minute2(ii) a Pressurizing for 4min at a rate of 15g/cm per minute2(ii) a Pressurizing for 5min at a rate of 20g/cm per minute in the fourth stage2Co-pressurizing to 200g/cm2(ii) a The flow rate of the polishing solution is 10-12L/cm2。
2. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the mortar ground in the grinding 800 step consists of silicon carbide sand GC800 #: water: mortar dispersant 13.5KG:30L: 1.7L; the mortar ground in the grinding 2000 step consists of silicon carbide sand GC2000 #: water: mortar dispersant 13.5KG:30L: 1.7L.
3. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 2, wherein: the grinding effect in the grinding 800 step reaches that TTV is less than or equal to 5 mu m and Bow is less than or equal to 30 mu m, and the grinding effect in the grinding 2000 step reaches that TTV is less than or equal to 4 mu m and Bow is less than or equal to 25 mu m.
4. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the polishing effect of the polishing step is that the wafer TTV is less than or equal to 3 μm, the wafer Bow is less than or equal to 20 μm, the WARP is less than 40 μm, the PLTV is more than 95 percent, and the wafer has mirror surface effect and no stress.
5. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the lithium niobate wafer is an 8-inch lithium niobate wafer.
6. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the fixture adopted in the steps of grinding 800, grinding 2000 and polishing is a planetary wheel, and the wafer placement position in the planetary wheel adopts an eccentric design;
the wafer placing position is circular, and a rubber ring with the diameter of 200.2mm and the width of 5mm is arranged at the edge of the wafer placing position;
five circular drainage holes are distributed around the wafer placement position, the diameters of the five circular drainage holes are respectively one 60mm, two 40mm and two 20mm, the circle center of the wandering star wheel is used as the circle center, a circle with the diameter of 290mm is made, the wafer placement circle and the drainage holes are all inscribed with the circle, the circle center of the wafer placement circle and the circle center of the 60mm drainage hole are on the same diameter line and are positioned on two sides, the circle center of the 40mm drainage hole is positioned on the circle center of the wandering star wheel, the radius of the drainage empty circle center passing 60mm is used as a reference edge, the circle center of the drainage hole is respectively deflected leftwards and rightwards by 60 degrees, the circle center of the 20mm drainage hole is positioned on the circle center of the wandering star wheel, the radius of the.
7. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the slicing step is specifically that under the conditions that the linear velocity of a steel wire is 400-1000m/min and the temperature is 22 +/-2 ℃, the lithium niobate crystal bar is cut into a wafer with the thickness of 250-300 mu m by utilizing linear cutting equipment, and the TTV of the wafer is less than or equal to 10 mu m.
8. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the chamfering step specifically comprises the steps of chamfering by using a T-shaped grinding wheel, and chamfering the right angle of the lithium niobate wafer into a fillet of about R0.1 at the rotation speed of the grinding wheel of 600 plus one year at 1000rpm/min and at 22 +/-2 ℃.
9. The processing method of a large-size ultra-thin high-precision lithium niobate wafer according to claim 1, wherein: the blackening step is specifically that the wafer is placed in a blackening furnace for blackening treatment, the temperature is 300-.
10. A lithium niobate wafer obtained by the method for processing a large-sized ultra-thin high-precision lithium niobate wafer according to any one of claims 1 to 9.
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3860467A (en) * | 1974-02-22 | 1975-01-14 | Western Electric Co | Method of etching a surface of a substrate comprising LITAO{HD 3 {B and chemically similar materials |
CN103921205A (en) * | 2014-04-04 | 2014-07-16 | 德清晶辉光电科技有限公司 | Production process of 6-inch lithium niobate or lithium tantalite chips |
CN103978406A (en) * | 2014-05-12 | 2014-08-13 | 大连理工大学 | High-efficiency super-smooth chemical mechanical polishing method for lithium niobate crystal |
CN107378654A (en) * | 2017-09-26 | 2017-11-24 | 天通控股股份有限公司 | A kind of polishing method of lithium tantanate substrate |
CN107665813A (en) * | 2017-09-26 | 2018-02-06 | 天通控股股份有限公司 | A kind of processing method of lithium tantalate substrate |
CN110744364A (en) * | 2019-11-06 | 2020-02-04 | 天通控股股份有限公司 | Double-side polishing method for large-size ultrathin lithium niobate substrate |
-
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Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3860467A (en) * | 1974-02-22 | 1975-01-14 | Western Electric Co | Method of etching a surface of a substrate comprising LITAO{HD 3 {B and chemically similar materials |
CN103921205A (en) * | 2014-04-04 | 2014-07-16 | 德清晶辉光电科技有限公司 | Production process of 6-inch lithium niobate or lithium tantalite chips |
CN103978406A (en) * | 2014-05-12 | 2014-08-13 | 大连理工大学 | High-efficiency super-smooth chemical mechanical polishing method for lithium niobate crystal |
CN107378654A (en) * | 2017-09-26 | 2017-11-24 | 天通控股股份有限公司 | A kind of polishing method of lithium tantanate substrate |
CN107665813A (en) * | 2017-09-26 | 2018-02-06 | 天通控股股份有限公司 | A kind of processing method of lithium tantalate substrate |
CN110744364A (en) * | 2019-11-06 | 2020-02-04 | 天通控股股份有限公司 | Double-side polishing method for large-size ultrathin lithium niobate substrate |
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