CN107695796A - A kind of sapphire crystalline substance tile polishing method - Google Patents

A kind of sapphire crystalline substance tile polishing method Download PDF

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Publication number
CN107695796A
CN107695796A CN201610643820.1A CN201610643820A CN107695796A CN 107695796 A CN107695796 A CN 107695796A CN 201610643820 A CN201610643820 A CN 201610643820A CN 107695796 A CN107695796 A CN 107695796A
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China
Prior art keywords
polishing
crystalline substance
disk
rotating speed
brick
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CN201610643820.1A
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CN107695796B (en
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周群飞
饶桥兵
夏本权
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Lens Technology Changsha Co Ltd
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Lens Technology Changsha Co Ltd
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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
    • B24B29/00—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents
    • B24B29/02—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

A kind of sapphire crystalline substance tile polishing method, it is polished first by the first polishing step with small pressure, the slow-speed of revolution, the mode of big flow, effectively the sharp parts on brilliant brick surface is removed, reduce brilliant brick chipping and the scuffing of polishing disk.Then by the second polishing step high pressure, middle rotating speed, the appropriate mode amount of the being removed polishing for lowering flow, it is not saturating to reduce polishing, makes the sapphire crystalline substance brick surface through the first polishing step more smooth；Finally by the 3rd polishing step low-pressure, high rotating speed, it is ensured that brilliant brick polished surface finish.The present invention can make the surface of sapphire crystalline substance brick penetrating and reach mirror effect, provide platform for brilliant brick fault detection, workshop section's processing cost after saving；Effective cut-off defect stream leads to rear process, reduces board, manpower, auxiliary material and wastes.And polishing disk is also applied for the polishing of the nonmetallic fragment of brick such as aluminum oxide, zirconia ceramics without scuffing, without chipping, flawless, polishing method of the invention in polishing process.

Description

A kind of sapphire crystalline substance tile polishing method
Technical field
The present invention relates to sapphire polishing technical field, particularly, is related to a kind of sapphire crystalline substance tile polishing method.
Background technology
Sapphire composition is aluminum oxide (Al2O3), it is to be combined by three oxygen atoms and two aluminium atoms with covalent bond pattern Form, its crystal structure is hexagonal lattice structure, and there are A-Plane, C-Plane, M-Plane and R- in the section that it is often employed Plane. due to sapphire optics, to penetrate band very wide, all has good printing opacity from black light (190nm) to middle infrared ray Property, therefore by largely with optical element, infrared facility, the radium-shine lens materials of high intensity and photomask materials, it has loud The features such as speed, high temperature resistant, anticorrosive, high rigidity, high light transmittance, fusing point high (2045 DEG C), it is a kind of quite unmanageable material Material.
The sapphire tool of Artificial Growth has good wearability, and hardness is only second to diamond and reaches 9 grades of Mohs, while blue precious Stone compactness makes it have larger surface tension, and above-mentioned two characteristic is very suitable for the electronic touch such as mobile phone panel and clock Watch mirror face.But there is the bad defect such as more bubble, impurity, crystal boundary in the sapphire crystal ingot of Artificial Growth, process indigo plant Jewel crystalline substance brick surface after grinding machine is molded is in frosting, is directly difficult with the naked eye to see internal flaw clearly, its defect part typically will Chip is cut into brilliant brick, then to that could be screened after wafer polishing, because sapphire processing auxiliary material is costly, defect part adds Work causes very big cost to waste.
In the prior art, less, the disclosure of Chinese patent 201310605267.9 is related to the polishing scheme of sapphire crystalline substance brick The polishing both surfaces method of sapphire touch panel a kind of, the program are mainly polished to sapphire panel, and it polishes step Suddenly two steps are broadly divided into, first with big pressure, big rotating speed, big particle diameter, the mode of big flow is polished, then using low pressure Power, the slow-speed of revolution, small particle, the mode of low discharge are finely polished, and the first step uses big rotating speed in the program, big particle diameter, greatly Flow is polished, and in the case of big rotating speed and big particle diameter, the sharp parts of sapphire touch panel blank surface are easy to draw Hinder polishing disk, and sapphire touch panel is again than relatively thin (for thickness within 5mm, quality is within 50g), it is easy to chipping occurs Scrapped with crackle.And in two polishing steps of the program, Abrasive Particle Size in polishing fluid is different, in polishing process, it is necessary to Stock removal polishing liquid is changed, polishing process is discontinuous, and polishing efficiency is relatively difficult to ensure card.
The content of the invention
Present invention aims at a kind of optical grade sapphire crystalline substance brick glossing is provided, to solve what is proposed in background technology Problem.
To achieve the above object, the invention provides a kind of sapphire crystalline substance tile polishing method, with tool by sapphire crystalline substance brick Clamping is fixed between the upper polishing disk of Twp-sided polishing machine and lower polishing disk, and upper polishing disk uses resin copper with lower polishing disk Disk, polishing fluid use diamond polishing fluid, and diamond grain size of micropowder 90wt% above distribution of particles is in 2~7 μm of models in diamond polishing fluid In enclosing, pH=8~11 of polishing fluid, polishing disk temperature control between 22~33 DEG C, polishing process include successively performing with Lower three steps：
First polishing step：Rubbing head Stress control is in 0.35~0.6N/cm2, upper polishing disk rotating speed control is 10~20 Rev/min, downshort disk rotating speed is controlled at 8~15 revs/min, and polishing flow quantity control is in 15~20mL/min；
Second polishing step：Rubbing head Stress control is in 0.50~0.85N/cm2, upper polishing disk rotating speed control is 25~30 Rev/min, lower polishing disk rotating speed control is at 15~20 revs/min, and polishing flow quantity control is in 12~16mL/min；
3rd polishing step：Rubbing head Stress control is in 0.25~0.55N/cm2, upper polishing disk rotating speed control is 34~38 Rev/min, lower polishing disk rotating speed control is at 20~25 revs/min, and polishing flow quantity control is in 12~16mL/min.
Further, the polishing time of first polishing step is 7~15min, the polishing of second polishing step Time is 15~25min, and the polishing time of the 3rd polishing step is 5~12min.
Further, in first polishing step, the second polishing step and the 3rd polishing step, upper polishing disk and lower throwing The steering of CD is contrary, and from the first polishing step to the 3rd polishing step, the rotating speed of upper polishing disk and lower polishing disk is passed Increase.
Further, in first polishing step, the second polishing step and the 3rd polishing step, the rotating speed of upper polishing disk More than the rotating speed of lower polishing disk.
Further, the polishing flow quantity of the polishing step of polishing fluid flow-rate ratio first of second polishing step is small, the Three polishing steps are identical with the polishing flow quantity of the second polishing step.
Further, the sapphire crystalline substance brick thickness that the sapphire crystalline substance tile polishing method is polished is (i.e. between two burnishing surfaces Distance) be more than and 5mm and be less than 100mm, the size of long cross direction is respectively positioned between 35mm~220mm, the weight of monolithic crystalline substance brick For 50g~5000g.
Beneficial effect：The present invention is polished before section to sapphire crystalline substance brick, is then examined, can effectively be ended scarce Sunken stream leads to rear process, reduces board, manpower, auxiliary material and wastes, has saved processing cost.
As an improvement in order to ensure that sapphire crystalline substance brick polishes yield, brilliant brick corner angle chipping is reduced, the present invention proposes one Kind speed change polishing method, is polished, effectively by the first polishing step with small pressure, the slow-speed of revolution, the mode of big flow first The sharp parts on brilliant brick surface are removed, reduce brilliant brick chipping and the scuffing of polishing disk.Then used by the second polishing step High pressure, middle rotating speed, the appropriate mode amount of the being removed polishing for lowering flow, it is not saturating to reduce polishing, makes to walk through the first polishing Rapid sapphire crystalline substance brick surface is more smooth；Finally by the 3rd polishing step low-pressure, high rotating speed, it is ensured that brilliant brick polishes table Face finish.
The sapphire crystalline substance tile polishing method of the present invention is using Twp-sided polishing machine and diamond polishing fluid to sapphire crystalline substance brick surface Carry out twin polishing, make the surface of sapphire crystalline substance brick penetrating and without scratch, without chipping, flawless, according to the polishing of the present invention The two-sided penetrating disposable qualification rate of sapphire crystalline substance brick obtained by method is more than 80%, and the surface roughness of panel is less than 10nm, flatness are less than 30 μm, and product thickness tolerance is less than 20 μm after processing, and brilliant two machined surfaces of brick are penetrating, are especially suitable for crystalline substance Brick internal flaw is examined.
Verified through actual production, the present invention can effectively remove brilliant brick surface frosted trace, reach mirror effect, be brilliant brick Fault detection provides platform, workshop section's processing cost after saving；The polishing method of the present invention is also applied for aluminum oxide, zirconium oxide simultaneously The polishing of the nonmetallic fragment of brick such as ceramics.
In addition to objects, features and advantages described above, the present invention also has other objects, features and advantages. The present invention is further detailed explanation below.
Embodiment
Embodiments of the invention are described in detail below, but the present invention can be limited and covered according to claim Multitude of different ways implement.
Embodiment one
Sapphire crystalline substance brick clamping is fixed between the upper polishing disk of Twp-sided polishing machine and lower polishing disk with tool, upper polishing Disk and lower polishing disk use resin copper dish, and polishing fluid uses diamond polishing fluid, and diamond grain size of micropowder is main in diamond polishing fluid It is distributed in 3~5 μ ms, polishing fluid pH=9.6, polishing process includes three steps that the priority described in table 1 performs：
Table 1
Step Upper disk rotating speed Lower wall rotating speed Polish flow quantity Polishing disk temperature Rubbing head pressure Process time
The first step 15 revs/min 10 revs/min 18mL/min 28~33 DEG C 0.5N/cm2 10min
Second step 27 revs/min 17 revs/min 15mL/min 28~33 DEG C 0.75N/cm2 20min
3rd step 34 revs/min 24 revs/min 15mL/min 28~33 DEG C 0.35N/cm2 10min
In first polishing step of embodiment one, the second polishing step and the 3rd polishing step, upper polishing disk and lower polishing The steering of disk is contrary.
If the blank that the sapphire crystalline substance tile polishing method in embodiment one is polished is the indigo plant that dry plate thickness is 40.35mm Jewel crystalline substance brick, the size of each long cross direction of sapphire crystalline substance brick is 36.75mm, and the weight of monolithic crystalline substance brick is located at 50g~1500g models In enclosing.
Embodiment two
Sapphire crystalline substance brick clamping is fixed between the upper polishing disk of Twp-sided polishing machine and lower polishing disk with tool, upper polishing Disk and lower polishing disk use resin copper dish, and polishing fluid uses diamond polishing fluid, and diamond grain size of micropowder is main in diamond polishing fluid It is distributed in 5~7 μ ms, polishing fluid pH=9.2, polishing process includes three steps that the priority described in table 2 performs：
Table 2
In first polishing step of embodiment two, the second polishing step and the 3rd polishing step, upper polishing disk and lower polishing The steering of disk is contrary.
If the blank that the sapphire crystalline substance tile polishing method in embodiment two is polished is the indigo plant that dry plate thickness is 64.5mm Jewel crystalline substance brick, each a width of 135.5mm of sapphire crystalline substance brick, the size of length direction are respectively positioned between 80~160mm, monolithic crystalline substance brick Weight is located in the range of 1000g~3000g.
Embodiment three
Sapphire crystalline substance brick clamping is fixed between the upper polishing disk of Twp-sided polishing machine and lower polishing disk with tool, upper polishing Disk and lower polishing disk use resin copper dish, and polishing fluid uses diamond polishing fluid, and diamond grain size of micropowder is main in diamond polishing fluid It is distributed in 2~5 μ ms, polishing fluid pH=10, polishing process includes three steps that the priority described in table 3 performs：
Table 3
Step Upper disk rotating speed Lower wall rotating speed Polish flow quantity Polishing disk temperature Rubbing head pressure Process time
The first step 18 revs/min 13 revs/min 20ml/min 24~26 DEG C 0.55N/cm2 8min
Second step 28 revs/min 18 revs/min 12ml/min 24~26 DEG C 0.85N/cm2 15min
3rd step 38 revs/min 24 revs/min 12ml/min 24~26 DEG C 0.45N/cm2 10min
In first polishing step of embodiment three, the second polishing step and the 3rd polishing step, upper polishing disk and lower polishing The steering of disk is contrary.
If the blank that the sapphire crystalline substance tile polishing method in embodiment three is polished is the indigo plant that dry plate thickness is 30.5mm Jewel crystalline substance brick, a width of 35.5mm of sapphire crystalline substance brick, the size of each sapphire crystalline substance brick length direction be respectively positioned on 80mm~220mm it Between, the weight of monolithic crystalline substance brick is located in the range of 50g~1000g.
The sapphire for possessing two minute surfaces that polishing method according to embodiment one, embodiment two and embodiment obtains is brilliant Brick, surface roughness are respectively less than 10nm, and flatness is respectively less than 30 μm, and product thickness tolerance is respectively less than 20 μm after processing, and product adds For work yield up to 95%, brilliant two machined surfaces of brick are penetrating, are especially suitable for brilliant brick fault detection.Comparative example one
In comparative example one, the first polishing step is not provided with, remaining parameter and condition are identical with embodiment three, referring specifically to table 4。
Table 4
Step Upper disk rotating speed Lower wall rotating speed Polish flow quantity Polishing disk temperature Pressure Process time
The first step / / / / / 0min
Second step 28 revs/min 18 revs/min 12ml/min 24~26 DEG C 0.85N/cm2 15min
3rd step 38 revs/min 24 revs/min 12ml/min 24~26 DEG C 0.45N/cm2 10min
The result of comparative example one：The chipping that brilliant brick corner angle occur；Feed intake 35 blocks；Scratch 31 pieces；Yield 11.4%
Comparative example two
In comparative example two, upper polishing disk and lower polishing disk use soft polishing pad, and without using hard resin copper dish, its Remaining parameter and condition are identical with embodiment one, referring specifically to table 5.
Table 5
Step Upper disk rotating speed Lower wall rotating speed Polish flow quantity Polishing disk temperature Pressure Process time
The first step 15 revs/min 10 revs/min 18ml/min 28~33 DEG C 0.5N/cm2 10min
Second step 27 revs/min 17 revs/min 15ml/min 28~33 DEG C 0.75N/cm2 20min
3rd step 34 revs/min 24 revs/min 15ml/min 28~33 DEG C 0.35N/cm2 10min
The result：Upper machine 5min polishing disks damage；Experiment interruption can not be carried out.
Comparative example three
In comparative example three, upper polishing disk exchanges with lower polishing disk rotating speed (descends polishing disk rotating speed to turn more than upper polishing disk Speed), remaining parameter and condition and embodiment three are essentially identical, are specifically shown in Table 6.
Table 6
Step Lower wall rotating speed Upper disk rotating speed Polish flow quantity Polishing disk temperature Pressure Process time
The first step 18 revs/min 13 revs/min 20ml/min 24~26 DEG C 0.55N/cm2 10min
Second step 28 revs/min 18 revs/min 12ml/min 24~26 DEG C 0.85N/cm2 15min
3rd step 38 revs/min 24 revs/min 12ml/min 24~26 DEG C 0.45N/cm2 10min
The result：The chipping that brilliant brick corner angle occur；Feed intake 37 pieces；Face is not saturating 17 pieces；Yield 54%.
Comparative example four
In comparative example four, polishing fluid uses SiO2 polishing fluids, and SiO2 abrasive grain diameters are 0.5nm in SiO2 polishing fluids, remaining Condition and parameter and embodiment three are essentially identical, are specifically shown in Table 7.
Table 7
Step Upper disk rotating speed Lower wall rotating speed Polish flow quantity Polishing disk temperature Pressure Process time
The first step 18 revs/min 13 revs/min 20ml/min 24~26 DEG C 0.55N/cm2 10min
Second step 28 revs/min 18 revs/min 12ml/min 24~26 DEG C 0.85N/cm2 15min
3rd step 38 revs/min 24 revs/min 12ml/min 24~26 DEG C 0.45N/cm2 10min
The result：Without removal amount；Brilliant brick is not thrown, yield 0%.
The contrast effect of each embodiment and comparative example such as table 8：
Table 8
The preferred embodiments of the present invention are the foregoing is only, are not intended to limit the invention, for the skill of this area For art personnel, the present invention can have various modifications and variations.Within the spirit and principles of the invention, that is made any repaiies Change, equivalent substitution, improvement etc., should be included in the scope of the protection.

Claims (6)

1. a kind of sapphire crystalline substance tile polishing method, it is characterised in that sapphire crystalline substance brick clamping is fixed on twin polishing with tool Between the upper polishing disk of machine and lower polishing disk, upper polishing disk uses resin copper dish with lower polishing disk, and polishing fluid is thrown using diamond Light liquid, in diamond polishing fluid diamond grain size of micropowder 90wt% above distribution of particles in 2~7 μ ms, the pH=8 of polishing fluid~ 11, for polishing disk temperature control between 22~33 DEG C, polishing process includes following three steps successively performed：
First polishing step：Rubbing head Stress control is in 0.35~0.6N/cm2, the control of upper polishing disk rotating speed at 10~20 revs/min, Downshort disk rotating speed is controlled at 8~15 revs/min, and polishing flow quantity control is in 15~20mL/min；
Second polishing step：Rubbing head Stress control is in 0.50~0.85N/cm2, the control of upper polishing disk rotating speed 25~30 turns/ Point, lower polishing disk rotating speed control is at 15~20 revs/min, and polishing flow quantity control is in 12~16mL/min；
3rd polishing step：Rubbing head Stress control is in 0.25~0.55N/cm2, the control of upper polishing disk rotating speed 34~38 turns/ Point, lower polishing disk rotating speed control is at 20~25 revs/min, and polishing flow quantity control is in 12~16mL/min.
2. a kind of sapphire crystalline substance tile polishing method according to claim 1, it is characterised in that first polishing step Polishing time is 7~15min, and the polishing time of second polishing step is 15~25min, the throwing of the 3rd polishing step It is 5~12min between light time.
A kind of 3. sapphire crystalline substance tile polishing method according to claim 1, it is characterised in that first polishing step, In second polishing step and the 3rd polishing step, the steering of upper polishing disk and lower polishing disk is contrary, and from the first polishing step To the 3rd polishing step, the rotating speed of upper polishing disk and lower polishing disk is incremented by.
A kind of 4. sapphire crystalline substance tile polishing method according to claim 1, it is characterised in that first polishing step, In second polishing step and the 3rd polishing step, the rotating speed of upper polishing disk is all higher than the rotating speed of lower polishing disk.
5. a kind of sapphire crystalline substance tile polishing method according to claim 1, it is characterised in that second polishing step The polishing flow quantity of the polishing step of polishing fluid flow-rate ratio first is small, the polishing flow quantity of the 3rd polishing step and the second polishing step It is identical.
6. a kind of sapphire crystalline substance tile polishing method according to any one in Claims 1 to 5, it is characterised in that described The sapphire crystalline substance brick thickness that sapphire crystalline substance tile polishing method is polished is more than 5mm and is less than 100mm, the equal position of size of long cross direction Between 35mm~220mm, the weight of monolithic crystalline substance brick is 50g~5000g.
CN201610643820.1A 2016-08-08 2016-08-08 A kind of sapphire crystalline substance tile polishing method Active CN107695796B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110434681A (en) * 2019-07-24 2019-11-12 中国科学院上海光学精密机械研究所 The two-sided high-precision polishing method of heavy caliber sapphire window element

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110434681A (en) * 2019-07-24 2019-11-12 中国科学院上海光学精密机械研究所 The two-sided high-precision polishing method of heavy caliber sapphire window element
CN110434681B (en) * 2019-07-24 2021-09-07 中国科学院上海光学精密机械研究所 Double-side high-precision polishing method for large-caliber sapphire window element

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