WO2013099083A1 - Procédé de fabrication d'un substrat en verre pour un lecteur de disque dur - Google Patents

Procédé de fabrication d'un substrat en verre pour un lecteur de disque dur Download PDF

Info

Publication number
WO2013099083A1
WO2013099083A1 PCT/JP2012/007072 JP2012007072W WO2013099083A1 WO 2013099083 A1 WO2013099083 A1 WO 2013099083A1 JP 2012007072 W JP2012007072 W JP 2012007072W WO 2013099083 A1 WO2013099083 A1 WO 2013099083A1
Authority
WO
WIPO (PCT)
Prior art keywords
glass substrate
polishing
colloidal silica
lubricating layer
cleaning
Prior art date
Application number
PCT/JP2012/007072
Other languages
English (en)
Japanese (ja)
Inventor
河合　秀樹
小松　隆史
Original Assignee
コニカミノルタ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by コニカミノルタ株式会社 filed Critical コニカミノルタ株式会社
Publication of WO2013099083A1 publication Critical patent/WO2013099083A1/fr

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G11B5/8404—Processes or apparatus specially adapted for manufacturing record carriers manufacturing base layers

Definitions

  • the present invention relates to a method for manufacturing a glass substrate for HDD. More specifically, the present invention includes a rinsing process for cleaning the polishing pad and a lubrication layer forming process for providing a lubrication layer on the polishing pad in the mirror polishing process, thereby suppressing micro-waviness of the glass substrate to be obtained and flattening.
  • the present invention relates to a method for manufacturing a glass substrate for HDD, which can increase the degree.
  • a glass substrate for HDD (hereinafter sometimes simply referred to as a glass substrate) is required to have small undulation and high flatness.
  • the micro waviness refers to the height of micro unevenness measured at a constant measurement wavelength using a surface roughness measuring machine.
  • flatness means the distance (height difference) of the up-down direction of the highest part and the lowest part of the glass substrate surface.
  • the fine waviness and flatness can be adjusted mainly by precisely polishing both main surfaces of the glass substrate in the mirror polishing process. According to recent research, it is known that micro waviness can be improved by adjusting the opening diameter of a polishing pad used in a mirror polishing process (see Patent Document 1).
  • the glass substrate that has undergone the mirror polishing process is sent to the subsequent chemical strengthening process and final cleaning process.
  • the chemical strengthening step for example, the glass substrate is immersed in a processing tank that stores the strengthening treatment liquid.
  • the final cleaning step for example, the glass substrate is immersed in a storage container in which the cleaning liquid is stored. Since the abrasive slurry remains on the surface of the glass substrate after the mirror polishing process, there is a problem that the glass substrate contaminates the strengthening treatment liquid and the cleaning liquid. Therefore, the glass substrate that has finished the mirror polishing process is washed on the surface plate. At this time, the polishing pad on the surface plate is also cleaned together with the glass substrate.
  • the present invention has been made in view of such a conventional problem, and in a method for producing a glass substrate having a mirror polishing step having a cleaning step, a glass substrate having excellent flatness and less microwaviness. It aims at providing the manufacturing method of the glass substrate for obtaining.
  • a method for producing a glass substrate according to one aspect of the present invention includes a mirror polishing process using a double-side polishing machine having upper and lower surface plates provided with polishing pads, and the mirror polishing process includes polishing the glass substrate after mirror polishing and polishing.
  • the colloidal silica has an average primary particle diameter of 15 to 90 nm, and the surface density of the colloidal silica in the lubricating layer is 10 to 500 particles / ⁇ m 2 .
  • a process of cleaning a glass substrate that has undergone mirror polishing is referred to as a rinsing process in order to distinguish it from cleaning in a final cleaning process subsequent to the mirror polishing process.
  • the glass substrate is, for example, a blanks manufacturing process, a first grinding process, a coring process, an inner / outer grinding process, an inner circumference polishing process, an outer circumference polishing process, a second grinding process, a first It is manufactured through a polishing step (rough polishing step), a second polishing step (mirror polishing step), a chemical strengthening step, and a final cleaning step.
  • the mirror polishing process includes a rinsing process and a lubricating layer forming process.
  • the mirror polishing process which is a characteristic part of the present embodiment will be described in detail.
  • the mirror polishing process is a polishing process performed on a glass substrate that has been subjected to a rough polishing process described later, and is a process of precisely polishing using a double-side polishing machine.
  • a double-side polishing machine (for example, 16B type manufactured by Hamai Sangyo Co., Ltd.) polishes both main surfaces of a glass substrate while sandwiching them between upper and lower surface plates provided with polishing pads on the surface.
  • polishing pad used in the mirror polishing step it is preferable to use a soft pad having a lower hardness than the polishing pad used in the rough polishing step described later (for example, NP225 manufactured by Filwel, hardness Asker-C hardness 76).
  • a soft pad having a lower hardness than the polishing pad used in the rough polishing step described later for example, NP225 manufactured by Filwel, hardness Asker-C hardness 76.
  • Examples of such a polishing pad include urethane foam and suede polishing pads.
  • the surface of the polishing pad In order to reduce the fine waviness of the glass substrate that has undergone the mirror polishing process, it is preferable to cut the surface of the polishing pad by about 20 to 150 ⁇ m before starting the mirror polishing. When the cutting amount exceeds 150 ⁇ m, there is a tendency that minute undulation is likely to occur in the obtained glass substrate. On the other hand, when the cutting amount is less than 20 ⁇ m, the flatness of the obtained glass substrate may be lowered.
  • the polishing pad preferably has a holding part (holding means) for holding colloidal silica contained in a lubricating layer described later on the surface layer part.
  • the lubricating layer contains colloidal silica that is abrasive grains.
  • the holding portion is not particularly limited, and examples thereof include a plurality of opening holes formed on the foamed surface.
  • the depth of the opening hole is not particularly limited, and is generally 10 to 800 ⁇ m although it depends on the cutting amount of the polishing pad. Further, the average opening area of the opening holes is not particularly limited, and is approximately 0.0001 to 0.0010 mm 2 . Further, the number of opening holes is not particularly limited, and is generally 100 to 800 holes / mm 2 .
  • the colloidal silica held in the holding part continues to contact the glass substrate continuously during the mirror polishing process. Therefore, the polishing accuracy is improved, and the flatness of the obtained glass substrate can be further improved.
  • abrasive it is possible to use an abrasive slurry in which colloidal silica having an average primary particle size of 15 to 90 nm is dispersed in water as abrasive grains to form a slurry.
  • the mixing ratio of water and colloidal silica is preferably about 1: 9 to 3: 7.
  • the pH is preferably adjusted to 1.5 to 6.5 with an adjustment solution containing sulfuric acid.
  • the abrasive slurry is added continuously or as needed on the surface plate during the mirror polishing process.
  • the addition amount of the abrasive slurry is about 200 to 2000 mL / min.
  • the polishing amount of the glass substrate in the mirror polishing step is preferably about 2 to 5 ⁇ m. By setting the polishing amount in such a range, micro defects such as micro undulations generated on the surface of the glass substrate and micro scratches generated in the previous step can be satisfactorily removed. Further, the flatness of both main surfaces of the glass substrate can be reduced to less than 0.5 ⁇ m.
  • the load applied to the glass substrate by the polishing pad in the mirror polishing step is, for example, about 50 to 180 g / cm 2 .
  • the rinsing process is performed after the glass substrate is polished under the above conditions.
  • the rinsing step is a step of cleaning the abrasive slurry remaining on the glass substrate and the polishing pad after mirror polishing.
  • the glass substrate and the polishing pad are cleaned using a rinsing liquid.
  • the cleaning method is not particularly limited.
  • the glass slurry and the polishing pad may be gradually cleaned while replacing the abrasive slurry added at any time during mirror polishing with a rinse liquid.
  • the supply may be stopped and a rinse solution may be added.
  • the rinse liquid is not particularly limited, and, for example, pure water, deaerated water whose gas dissolved amount is adjusted, and the like can be used.
  • the addition amount of the rinse liquid is not particularly limited, and is about 0.5 to 20 L / min.
  • the addition amount of the rinsing liquid is less than 0.5 L / min, the glass substrate cannot be sufficiently cleaned, and the glass substrate may contaminate the tempering treatment liquid or the cleaning liquid in the subsequent chemical strengthening process or the final cleaning process. There is.
  • the addition amount of the rinsing liquid exceeds 20 L / min, there is a possibility that improvement of the cleaning effect on the glass substrate cannot be expected.
  • the addition pressure of the rinsing liquid is not particularly limited, and it is added to a glass substrate or polishing pad at a water pressure of 100 to 500 kPa.
  • the addition pressure of the rinsing liquid is less than 100 kPa, the glass substrate or the polishing pad may not be sufficiently cleaned.
  • the addition pressure of the rinsing liquid exceeds 500 kPa, the glass substrate and the polishing pad may be damaged.
  • the temperature of the rinse liquid is not particularly limited, and is about 5 to 50 ° C. When the temperature of the rinse liquid is less than 5 ° C., the glass substrate may not be sufficiently cleaned. On the other hand, when the rinse liquid is washed at a temperature exceeding 50 ° C., the glass substrate may be deformed or the polishing pad may be deteriorated.
  • the glass substrate that has undergone the rinsing process is sent to the subsequent chemical strengthening process and the final cleaning process. Since the glass substrate is cleaned cleanly by the rinsing process, the strengthening treatment liquid and the cleaning liquid are not extremely contaminated. On the other hand, the surface of the surface plate provided with the polishing pad that has undergone the rinsing process is cleaned cleanly. In the present embodiment, a lubricating layer is formed on such a polishing pad.
  • the lubricating layer forming step is a step of adding an abrasive slurry containing colloidal silica to the polishing pad to form a lubricating layer on the surface of the polishing pad.
  • a slurry in which colloidal silica having an average primary particle diameter of 15 to 90 nm is dispersed in water as abrasive grains can be used.
  • the average primary particle diameter of the colloidal silica is less than 15 nm, the particle diameter of the colloidal silica held in the lubricating layer described later is too small, so that sufficient lubrication performance tends not to be obtained.
  • it exceeds 90 nm since the particle diameter of colloidal silica held in the lubricating layer described later is too large, the fine undulation tends to increase.
  • the mixing ratio of water and colloidal silica is preferably about 1: 9 to 3: 7. If necessary, it is preferable to adjust the pH to 1.5 to 6 with an adjusting solution containing sulfuric acid.
  • the abrasive slurry used in the lubricating layer forming step can be the same as the abrasive slurry used during the mirror polishing step.
  • a new glass substrate can be placed on a surface plate having a polishing pad on which a lubricating layer is formed, and the time required to start mirror polishing can be shortened.
  • the method of adding the abrasive slurry in the lubricating layer forming step is not particularly limited.
  • the abrasive slurry may be added by supplying from the outside through a through-hole disposed on the upper surface plate of the double-side polishing machine.
  • the slurry can be added by a method such as immersing it in a storage container storing the slurry.
  • the surface density of colloidal silica in the lubricating layer is 10 to 500 / ⁇ m 2 , and more preferably 100 to 250 / ⁇ m 2 .
  • the surface density is less than 10 pieces / ⁇ m 2 , the flatness of the glass substrate obtained by mirror polishing tends to deteriorate.
  • the surface density exceeds 500 / ⁇ m 2 , many defects tend to be formed on the main surface and the end surface of the glass substrate after the mirror polishing.
  • a defect refers to an area or location that cannot be recorded to the extent that it can be accurately reproduced due to scratches or dust existing on the glass substrate, deterioration of the glass substrate, or the like.
  • the surface density is adjusted to the above range by adjusting the proportion of colloidal silica contained in the abrasive slurry, the average primary particle diameter, the depth, number, and area of the openings formed in the polishing pad surface. Can do.
  • the manufacturing method of the glass substrate of this Embodiment should just have an above-described mirror polishing process, and it does not specifically limit about other processes. For this reason, the other steps described below are examples, and the design can be changed as appropriate.
  • the blanks manufacturing process is a process of melting a glass material and obtaining a glass substrate (blanks) from the molten glass material.
  • the glass material examples include soda lime glass, aluminosilicate glass, borosilicate glass, Li 2 O—SiO 2 glass, Li 2 O—Al 2 O 3 —SiO 2 glass, R′O—Al 2 O 3.
  • the method for obtaining blanks is not particularly limited, and for example, a method of obtaining a disk-shaped glass substrate (blanks) by pouring a molten glass material into a lower mold and press molding with an upper mold can be employed.
  • blanks are not restricted to press molding, For example, you may cut and produce the sheet glass formed by the down draw method, the float method, etc. with the grinding stone. In this molding process, foreign matter and bubbles are mixed in the vicinity of the surface of the blank, or scratches are generated, resulting in defects.
  • the size of the blanks is not particularly limited, and for example, blanks having various outer diameters of 2.5 inches, 1.8 inches, 1 inch, 0.8 inches, and the like can be produced. It does not specifically limit about the thickness of a glass substrate, For example, blanks of various thickness, such as 2 mm, 1 mm, 0.8 mm, 0.63 mm, can be produced.
  • Blanks produced by press molding or cutting can be alternately laminated with heat-stable setters and passed through a high-temperature electric furnace to promote reduction of warpage and crystallization of glass.
  • the first grinding step is a step of preliminarily adjusting the parallelism, flatness and thickness of the glass substrate by grinding both surfaces of the blank.
  • the main surface of the blank is lapped (ground) to obtain a glass base material.
  • the lapping process is performed using alumina-based loose abrasive grains by a double-sided lapping apparatus using a planetary gear mechanism. Specifically, in the lapping process, both main surfaces of the blanks are pressed against the lapping platen from above and below, a grinding liquid containing free abrasive grains is supplied onto the main surface of the plate glass, and these are moved relatively. Do it. By this lapping process, a glass substrate having a flat main surface is obtained.
  • the coring step is a step of opening a circular hole (center hole) in the center of the glass substrate.
  • the coring step is a step of forming an annular glass substrate by forming an inner hole at the center of the glass substrate using a cylindrical diamond drill.
  • the inner / outer grinding step is a step in which the inner peripheral end surface and the outer peripheral end surface of the glass substrate are ground with a drum-shaped grinding wheel using diamond or the like and subjected to a predetermined chamfering process.
  • the inner peripheral polishing step is a step of alternately laminating glass substrates and spacers one by one to create a laminate, and polishing the inner peripheral end surface with an inner peripheral end surface polishing machine.
  • the spacer is not particularly limited.
  • a spacer made of polypropylene having a thickness of 0.3 mm, an inner diameter of 21 mm, and an outer diameter of 64 mm can be employed.
  • nylon fibers having a diameter of 0.2 mm can be used for the brush bristles of the polishing machine.
  • the number of rotations of the rotating brush can be set to 10,000 rpm, for example.
  • As the polishing liquid for inner circumference polishing for example, a polishing liquid containing a hydrofluoric acid solvent can be used, and as the polishing agent, for example, cerium oxide having an average primary particle diameter of 3 ⁇ m can be used.
  • the outer peripheral polishing step is a step of alternately laminating glass substrates and spacers one by one to create a laminate, and polishing the outer peripheral end surface by an outer peripheral end surface polishing machine.
  • the polishing conditions of the spacer and the polishing machine used are the same as those used in the inner peripheral polishing step.
  • the second grinding step is a step of grinding both main surfaces of the glass substrate to remove large scratches and improve flatness.
  • both main surfaces of the glass substrate are lapped with a lapping machine (manufactured by HAMAI).
  • the wrapping conditions are not particularly limited.
  • diamond pellets of # 1500 mesh can be used, the load can be 100 g / cm 2 , the upper surface plate can be rotated at 30 rpm, and the lower surface plate can be rotated at 10 rpm.
  • Rmax is about 3 ⁇ m and Ra is about 0.3 ⁇ m.
  • the glass substrate that has undergone the second grinding step is substantially free from defects such as large undulations, chippings, and cracks.
  • the grinding liquid or glass powder remains on the surface of the glass substrate that has undergone the grinding process. Therefore, in this embodiment, it is preferable to provide a cleaning process.
  • various cleaning methods can be employed.
  • the glass substrate may be subjected only to alkali cleaning, may be subjected to acid cleaning after acid cleaning, or may be only subjected to acid cleaning.
  • the rough polishing step is a step of polishing both surfaces of the glass substrate so as to efficiently obtain the surface roughness finally required in the subsequent mirror polishing step. It does not specifically limit as a grinding
  • the polishing liquid preferably uses cerium oxide having an average primary particle size of 0.6 to 2.5 ⁇ m as abrasive grains, and the abrasive grains are dispersed in water to form a slurry.
  • the mixing ratio of water and cerium oxide is about 1: 9 to 3: 7.
  • the polishing amount of the glass substrate in the rough polishing step is preferably about 25 to 40 ⁇ m. When the polishing amount of the glass substrate is less than 25 ⁇ m, there is a tendency that scratches and defects cannot be sufficiently removed. On the other hand, when the polishing amount of the glass substrate exceeds 40 ⁇ m, polishing is performed more than necessary, and the production efficiency tends to decrease.
  • ⁇ Second polishing step (mirror polishing step)>
  • the mirror polishing process has already been described above.
  • the manufacturing method of the glass substrate of this Embodiment has a rinse process in a mirror polishing process, and the glass substrate which finished mirror polishing is wash
  • the present embodiment includes the lubricating layer forming step, the lubricating layer is formed on the polishing pad cleaned by the rinsing step.
  • the chemical strengthening step is a step of immersing the glass substrate in a strengthening treatment solution to improve the impact resistance, vibration resistance, heat resistance, and the like of the glass substrate.
  • the chemical strengthening method employed in the chemical strengthening step is not particularly limited, but usually, a glass substrate is immersed in a heated strengthening treatment solution, and alkali ions (for example, lithium ions) contained in the glass substrate have a relatively small ion radius.
  • An ion exchange method is employed in which ions are replaced with alkali ions having a larger ion radius (for example, potassium ions and sodium ions).
  • a reinforcing layer ion exchange layer and compressive stress layer
  • the obtained glass substrate has a uniform chemical strengthening layer, a uniform compressive strain, hardly deforms, has good flatness, and is excellent in mechanical strength.
  • the waiting time and the water temperature in the water immersing step are not particularly limited.
  • the water temperature may be waited for 1 to 60 seconds in the air and immersed in water at about 35 to 100 ° C., and is appropriately determined in consideration of manufacturing efficiency.
  • the final cleaning step is a step of cleaning and cleaning the glass substrate. It does not specifically limit as a washing
  • the cleaned glass substrate is subjected to ultrasonic cleaning and drying as necessary.
  • the drying step is a step of drying the surface of the glass substrate after removing the cleaning liquid remaining on the surface of the glass substrate with isopropyl alcohol (IPA) or the like.
  • IPA isopropyl alcohol
  • the final cleaning step for example, a step of performing a water rinsing cleaning step on the glass substrate after the scrub cleaning for 2 minutes to remove a residue of the cleaning liquid can be employed.
  • an IPA cleaning process is performed for 2 minutes, and a process of removing water remaining on the surface of the glass substrate by IPA can be employed.
  • the final cleaning step may employ a step of performing the IPA vapor drying step for 2 minutes and drying while removing the liquid IPA adhering to the surface of the glass substrate with the IPA vapor.
  • the method for drying the glass substrate is not particularly limited, and a known drying method such as spin drying or air knife drying can be employed. After the glass substrate that has undergone these steps is inspected for scratches, cracks, adhesion of foreign matter, etc. visually or using an optical surface analyzer (for example, “OSA6100” manufactured by KLA-TENCOL), the foreign matter etc. In a clean environment, it is stored in a dedicated storage cassette, vacuum packed, and then shipped.
  • a known drying method such as spin drying or air knife drying can be employed.
  • the present embodiment is not limited to the HDD manufacturing method, and can be used as a manufacturing method of a magneto-optical disk, an optical disk, or the like.
  • this embodiment is designed to change the grinding process into two processes in order, to omit the rough polishing process, to perform the chemical strengthening process before the mirror polishing process, etc. Is possible.
  • the present embodiment may perform chemical strengthening treatment on the outer peripheral end face and inner peripheral end face other than the main surface of the glass substrate as a measure for drop strength, or as an edge mitigation process for scratches generated on the glass substrate.
  • the substrate may be subjected to a hydrogen fluoride immersion treatment.
  • the manufacturing method of the glass substrate for HDD for obtaining the glass substrate which has the outstanding flatness and few microwaviness can be provided.
  • the method for producing a glass substrate of the present invention has a mirror polishing process using a double-side polishing machine having upper and lower surface plates provided with a polishing pad, and the mirror polishing process is performed on the glass substrate and the polishing pad after mirror polishing.
  • the average primary particle diameter of the colloidal silica is 15 to 90 nm, and the surface density of the colloidal silica in the lubricating layer is 10 to 500 particles / ⁇ m 2 .
  • the glass substrate is less likely to contaminate the cleaning liquid in the subsequent process.
  • the cleaned polishing pad of the surface plate has a lubrication layer newly containing colloidal silica. Therefore, when the glass substrate before mirror polishing is newly arranged on the surface plate, a large frictional force is unlikely to be generated between the glass substrate and the polishing pad. As a result, when mirror polishing is started, the glass substrate smoothly moves horizontally, and the horizontality of the glass substrate during mirror polishing is maintained. Therefore, a glass substrate having excellent flatness and less microwaviness can be obtained.
  • the polishing pad has a holding means for holding the lubricating layer on the surface layer portion.
  • the polishing pad has the holding means, the colloidal silica abrasive grains are continuously held on the surface layer portion of the polishing pad during the mirror polishing process, and can come into contact with the glass substrate. As a result, the polishing accuracy is improved, and the flatness of the resulting glass substrate can be further improved.
  • the manufacturing method of the glass substrate of this invention is explained in full detail by an Example.
  • the manufacturing method of the glass substrate of this invention is not limited to the Example shown below at all.
  • a glass substrate was prepared by the following method.
  • polishing slurry was added to the polishing pad, and a lubricating layer was formed on the polishing pad.
  • the added polishing slurry was a slurry obtained by dispersing colloidal silica having an average primary particle size of 20 nm as abrasive grains (polishing component) in water.
  • the mixing ratio of water and abrasive grains in the polishing slurry was adjusted between 99: 1 and 80:20 so that the surface density of the colloidal silica in the lubricating layer of the polishing pad was a predetermined value.
  • the pH was adjusted to 4.5 with an adjusting solution containing sulfuric acid.
  • the surface density of the colloidal silica in the lubricating layer of the obtained polishing pad was 120 / ⁇ m 2 .
  • the surface density was calculated by drying the polishing pad with the lubricating layer formed and measuring the number of colloidal silica particles on the surface with a scanning electron microscope (SEM). About the aggregated colloidal silica, the number was estimated from the area, and it was set as the number of particles of colloidal silica.
  • both main surfaces of the glass substrate were polished more precisely by using a double-side polishing machine (Type 16B, manufactured by Hamai Sangyo Co., Ltd.).
  • abrasive slurry colloidal silica having an average primary particle diameter of 20 nm was dispersed in water as abrasive grains (polishing liquid component) to form a slurry, and the mixing ratio of water and abrasive grains was 80:20 did.
  • pH was adjusted with the adjustment liquid containing a sulfuric acid.
  • the load was 120 g / cm 2 . In this step, 100 batches of glass substrates were processed into 5 batches.
  • the obtained glass substrate was chemically strengthened.
  • the chemical strengthening treatment liquid an aqueous solution of a mixed molten salt of potassium nitrate (KNO 3 ) and sodium nitrate (NaNO 3 ) was used. The mixing ratio was 1: 1 by mass ratio. The temperature of the chemical strengthening treatment liquid was 380 ° C., and the immersion time was 25 minutes.
  • the glass substrate was scrubbed.
  • a cleaning liquid a liquid obtained by diluting KOH and NaOH mixed at a mass ratio of 1: 1 with ultrapure water (DI water) and adding a nonionic surfactant to enhance the cleaning performance is obtained.
  • DI water ultrapure water
  • the cleaning liquid was supplied by spraying. After scrub cleaning, in order to remove the cleaning liquid remaining on the surface of the glass substrate, a water rinse cleaning process is performed in an ultrasonic bath for 2 minutes, an IPA cleaning process is performed in an ultrasonic bath for 2 minutes, and finally the glass substrate is cleaned with IPA vapor. The surface of was dried.
  • Example 2 A glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 200 pieces / ⁇ m 2 .
  • Example 3 A glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 400 / ⁇ m 2 .
  • Example 4 A glass substrate was produced in the same manner as in Example 1 except that the average primary particle diameter of colloidal silica in the lubricating layer forming step was 80 nm and the surface density was 200 particles / ⁇ m 2 .
  • Example 5 A glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 12 / ⁇ m 2 .
  • Example 6 A glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 80 / ⁇ m 2 .
  • Example 1 A glass substrate was produced in the same manner as in Example 1 except that the lubricating layer forming step was not adopted.
  • a glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 8 pieces / ⁇ m 2 .
  • Example 3 A glass substrate was produced in the same manner as in Example 1 except that the surface density of the colloidal silica in the lubricating layer forming step was 800 pieces / ⁇ m 2 .
  • Example 4 A glass substrate was produced in the same manner as in Example 1 except that the average primary particle diameter of colloidal silica in the lubricating layer forming step was 10 nm.
  • Example 5 A glass substrate was produced in the same manner as in Example 1 except that the average primary particle diameter of colloidal silica in the lubricating layer forming step was 100 nm and the surface density was 200 particles / ⁇ m 2 .
  • the glass substrates obtained in Examples 1 to 6 and Comparative Examples 1 to 5 were subjected to flatness measurement, microwaviness measurement, and deposit inspection. The test method is shown below, and the results are shown in Table 1.
  • Comparative Example 4 since the average primary particle diameter of the colloidal silica held in the lubricating layer was small, sufficient lubrication performance was not exhibited, friction acted on the substrate at the initial stage of processing, and the flatness was 0.6 ⁇ m or more. It was. In Comparative Example 5, since the average primary particle diameter of the colloidal silica held in the lubricating layer was too large, the value of the microwaviness was high.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Surface Treatment Of Glass (AREA)
  • Manufacturing Of Magnetic Record Carriers (AREA)

Abstract

Le présent procédé de fabrication d'un substrat en verre pour un lecteur de disque dur est caractérisé en ce que : le procédé comporte une étape au cours de laquelle une machine de polissage double face est utilisée ; l'étape comporte une étape de nettoyage d'une boue d'agent de polissage laissée sur le substrat en verre ou similaire après le polissage, et une étape de formation d'une couche de lubrification en ajoutant, au tampon de polissage, la boue d'agent de polissage contenant une silice colloïdale ; le diamètre de particule principale moyen de la silice colloïdale est de 15 à 90 nm ; et la densité de surface de la silice colloïdale dans la couche de lubrification est de 10 à 500 particules/µm2. Dans ce procédé de fabrication, le substrat en verre ayant une excellente planéité et moins de voilement fin peut être obtenu.
PCT/JP2012/007072 2011-12-27 2012-11-05 Procédé de fabrication d'un substrat en verre pour un lecteur de disque dur WO2013099083A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011-286097 2011-12-27
JP2011286097 2011-12-27

Publications (1)

Publication Number Publication Date
WO2013099083A1 true WO2013099083A1 (fr) 2013-07-04

Family

ID=48696636

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/007072 WO2013099083A1 (fr) 2011-12-27 2012-11-05 Procédé de fabrication d'un substrat en verre pour un lecteur de disque dur

Country Status (1)

Country Link
WO (1) WO2013099083A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016016505A (ja) * 2014-07-11 2016-02-01 旭硝子株式会社 研磨パッドの洗浄方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001006162A (ja) * 1999-06-24 2001-01-12 Mitsubishi Chemicals Corp 磁気ディスク用基板の製造方法
JP2001155332A (ja) * 1999-09-27 2001-06-08 Fujimi America Inc 研磨用組成物およびそれを用いたメモリーハードディスクの製造方法
WO2004058450A1 (fr) * 2002-12-26 2004-07-15 Hoya Corporation Procede de production d'un substrat en verre pour support d'enregistrement d'informations, appareil de polissage et substrat en verre pour support d'enregistrement d'informations
JP2006095677A (ja) * 2004-08-30 2006-04-13 Showa Denko Kk 研磨方法
JP2006351081A (ja) * 2005-06-14 2006-12-28 Fuji Electric Holdings Co Ltd 磁気ディスク基板の研磨方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001006162A (ja) * 1999-06-24 2001-01-12 Mitsubishi Chemicals Corp 磁気ディスク用基板の製造方法
JP2001155332A (ja) * 1999-09-27 2001-06-08 Fujimi America Inc 研磨用組成物およびそれを用いたメモリーハードディスクの製造方法
WO2004058450A1 (fr) * 2002-12-26 2004-07-15 Hoya Corporation Procede de production d'un substrat en verre pour support d'enregistrement d'informations, appareil de polissage et substrat en verre pour support d'enregistrement d'informations
JP2006095677A (ja) * 2004-08-30 2006-04-13 Showa Denko Kk 研磨方法
JP2006351081A (ja) * 2005-06-14 2006-12-28 Fuji Electric Holdings Co Ltd 磁気ディスク基板の研磨方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016016505A (ja) * 2014-07-11 2016-02-01 旭硝子株式会社 研磨パッドの洗浄方法

Similar Documents

Publication Publication Date Title
US20100247977A1 (en) Subastrate for a magnetic disk and method of manufacturing the same
JP2009193608A (ja) 情報記録媒体用ガラス基板の製造方法、情報記録媒体用ガラス基板及び磁気記録媒体
WO2013046583A1 (fr) Substrat de verre hdd, procédé de production pour substrat de verre hdd, et procédé de production pour support d'enregistrement d'informations hdd
JP2012089221A (ja) 磁気記録媒体用ガラス基板の製造方法
US20100081013A1 (en) Magnetic disk substrate and magnetic disk
JP2010079948A (ja) 磁気ディスク用ガラス基板の製造方法
JP2014188668A (ja) ガラス基板の製造方法
JP2007102843A (ja) 磁気記録媒体用ガラス基板および磁気ディスク
JP6419578B2 (ja) ハードディスク用ガラス基板の製造方法
JP5977520B2 (ja) 磁気ディスク用ガラス基板の製造方法および磁気ディスク用ガラス基板
WO2014208270A1 (fr) Procédé de fabrication de substrat en verre pour support d'enregistrement d'informations
JP4723341B2 (ja) 磁気記録媒体用ガラス基板および磁気ディスクの製造方法
WO2013099083A1 (fr) Procédé de fabrication d'un substrat en verre pour un lecteur de disque dur
JP6059739B2 (ja) ハードディスク用ガラス基板の製造方法
JP2010238298A (ja) 磁気ディスク用ガラス基板の製造方法
JP6034580B2 (ja) Ｈｄｄ用ガラス基板の製造方法
JP2015069662A (ja) Ｈｄｄ用ガラス基板の製造方法
JP5719030B2 (ja) 研磨パッドおよび該研磨パッドを用いたガラス基板の製造方法
JP5859757B2 (ja) Ｈｄｄ用ガラス基板の製造方法
JP5897959B2 (ja) 情報記録媒体用ガラス基板の製造方法
JP2010238303A (ja) 磁気ディスク用ガラス基板の製造方法
WO2014156189A1 (fr) Substrat en verre pour disque dur et son procédé de fabrication
JP5886108B2 (ja) 情報記録媒体用ガラス基板の製造方法
JP2011067901A (ja) 磁気ディスク用ガラス基板の製造方法
WO2013099087A1 (fr) Procédé de fabrication d'un substrat de verre hdd

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12862827

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12862827

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP

122 Ep: pct application non-entry in european phase

Ref document number: 12862827

Country of ref document: EP

Kind code of ref document: A1